docs: simplify the readme.

'(a b c) = (quote (a b c))

Jellyfin.Plugin.SmartPlaylist/Lisp/Compiler/Parser.cs

@@ -1,269 +1,7 @@
 using System.Diagnostics;
+using Jellyfin.Plugin.SmartPlaylist.Lisp;
 
 namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
-    interface IAddable<T> where T : IAddable<T> {
-        static abstract T operator +(T left, T right);
-    }
-
-    interface ISubtractable<T> where T : ISubtractable<T> {
-        static abstract T operator -(T left, T right);
-    }
-
-    interface IMultiplicatable<T> where T : IMultiplicatable<T> {
-        static abstract T operator *(T left, T right);
-    }
-
-    interface IDivisible<T> where T : IDivisible<T> {
-        static abstract T operator /(T left, T right);
-        static abstract T operator %(T left, T right);
-    }
-
-    interface ISortable<T, E> where T : ISortable<T, E> {
-        static abstract E operator >(T left, T right);
-        static abstract E operator <(T left, T right);
-        static abstract E operator >=(T left, T right);
-        static abstract E operator <=(T left, T right);
-    }
-
-    interface IComparable<T, E> where T : IComparable<T, E> {
-        static abstract E operator ==(T left, T right);
-        static abstract E operator !=(T left, T right);
-        E Equals(T other);
-    }
-
-    public abstract class Expression: IComparable<Expression, bool> {
-        public override abstract string ToString();
-        public abstract override int GetHashCode();
-        public abstract bool Equals(Expression other);
-        public override bool Equals(object? other) {
-            if (other is Expression other_e) {
-                return Equals(other_e);
-            }
-            return false;
-        }
-        public static bool operator ==(Expression left, Expression right) {
-            return left.Equals(right);
-        }
-        public static bool operator !=(Expression left, Expression right) {
-            return !left.Equals(right);
-        }
-        public abstract object Inner();
-    }
-    public abstract class Atom : Expression {}
-    public class Symbol : Atom {
-        private readonly string _name;
-        public Symbol(string name) {
-            _name = name;
-        }
-        public string name { get => _name; }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _name.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression? other) {
-            if (other is Symbol other_s) {
-                return _name == other_s._name;
-            }
-            return false;
-        }
-        public override string ToString() {
-            return _name;
-        }
-        public override object Inner() {
-            return _name;
-        }
-    }
-
-    public class Boolean : Atom {
-        private readonly bool _value;
-        public Boolean(bool value) {
-            _value = value;
-        }
-        public bool value { get => _value; }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _value.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression other) {
-            if (other is Boolean other_b) {
-                return _value == other_b.value;
-            }
-            return false;
-        }
-        public override string ToString() {
-            return _value? "t" : "nil";
-        }
-        public override object Inner() {
-            return _value;
-        }
-    }
-
-    public class Integer : Atom, IAddable<Integer>, ISubtractable<Integer>, IMultiplicatable<Integer>, IDivisible<Integer>, ISortable<Integer, Boolean> {
-        private readonly int _value;
-        public Integer(int value) {
-            _value = value;
-        }
-        public int value { get => _value; }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _value.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression other) {
-            if (other is Integer other_i) {
-                return _value == other_i._value;
-            }
-            return false;
-        }
-        public override string ToString() {
-            return _value.ToString();
-        }
-        public static Integer operator +(Integer a, Integer b) {
-            return new Integer(a.value + b.value);
-        }
-        public static Integer operator -(Integer a, Integer b) {
-            return new Integer(a.value - b.value);
-        }
-        public static Integer operator *(Integer a, Integer b) {
-            return new Integer(a.value * b.value);
-        }
-        public static Integer operator /(Integer a, Integer b) {
-            return new Integer(a.value / b.value);
-        }
-        public static Integer operator %(Integer a, Integer b) {
-            return new Integer(a.value % b.value);
-        }
-        public static Boolean operator >(Integer a, Integer b) {
-            return new Boolean(a.value > b.value);
-        }
-        public static Boolean operator <(Integer a, Integer b) {
-            return new Boolean(a.value < b.value);
-        }
-        public static Boolean operator >=(Integer a, Integer b) {
-            return new Boolean(a.value >= b.value);
-        }
-        public static Boolean operator <=(Integer a, Integer b) {
-            return new Boolean(a.value <= b.value);
-        }
-        public static Boolean operator ==(Integer a, Integer b) {
-            return new Boolean(a.value == b.value);
-        }
-        public static Boolean operator !=(Integer a, Integer b) {
-            return new Boolean(a.value != b.value);
-        }
-        public override object Inner() {
-            return _value;
-        }
-    }
-
-    public class String : Atom, IAddable<String> {
-        private readonly string _value;
-        public String(string value) {
-            _value = value;
-        }
-        public string value { get => _value; }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _value.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression other) {
-            if (other is String other_s) {
-                return _value == other_s._value;
-            }
-            return false;
-        }
-        public override string ToString() {
-            return "\"" + _value + "\"";
-        }
-        public static String operator +(String a, String b) {
-            return new String (a.value + b.value);
-        }
-        public override object Inner() {
-            return _value;
-        }
-    }
-
-    public class Object : Atom {
-        private readonly object _value;
-        public Object(object value) {
-            _value = value;
-        }
-        public object value { get => _value; }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _value.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression other) {
-            if (other is Object other_o) {
-                return _value == other_o._value;
-            }
-            return false;
-        }
-        public override string ToString() {
-            return _value.ToString();
-        }
-        public static Expression FromBase(object o) {
-            switch (o) {
-                case bool b:
-                    return new Boolean(b);
-                case int i:
-                    return new Integer(i);
-                case string s:
-                    return new String(s);
-                case IEnumerable<object> e:
-                    return new List(e.Select(x => Object.FromBase(x)).ToList());
-                default:
-                    return new Object(o);
-            }
-        }
-        public override object Inner() {
-            return _value;
-        }
-    }
-
-    public class List : Expression {
-        private IList<Expression> _expressions;
-        public List(IList<Expression> expressions) {
-            _expressions = expressions;
-        }
-        public IList<Expression> expressions { get => _expressions; }
-        public override int GetHashCode() {
-            int hash = 17;
-            foreach (Expression i in _expressions) {
-                hash *= 23;
-                hash += i.GetHashCode();
-            }
-            return hash;
-        }
-        public override bool Equals(Expression other) {
-            if (other is List other_l) {
-                return _expressions.SequenceEqual(other_l._expressions);
-            }
-            return false;
-        }
-        public override string ToString() {
-            return "(" + string.Join(" ", _expressions.Select(x => x.ToString())) + ")";
-        }
-        public static List operator +(List a, List b) {
-            List<Expression> r = new List<Expression>();
-            r.AddRange(a.expressions);
-            r.AddRange(b.expressions);
-            return new List(r);
-        }
-        public override object Inner() {
-            return _expressions.Select(x => x.Inner()).ToArray();
-        }
-    }
-
     public class Parser {
         private StringTokenStream _sts;
         public Parser(StringTokenStream tokens) {
@@ -280,17 +18,16 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                     return parse_grouping(gt, gt.closing_value);
                 case AtomToken at:
                     return parse_atom(at);
-                case OperatorToken ot:
-                    return parse_operator(ot);
                 case SpaceToken sp:
                     return parse();
             }
             return parse();
         }
 
-        Expression parse_string(GroupingToken start, GroupingToken end) {
+        Expression parse_string(GroupingToken start, GroupingToken? end) {
+            Debug.Assert(end != null);
             Debug.Assert(start.value == end.value);
-            Debug.Assert("'\"".Contains(start.value));
+            Debug.Assert("\"".Contains(start.value));
             string r = "";
             while (_sts.Available() > 0) {
                 Token<string> t = _sts.Get();
@@ -303,10 +40,36 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
             return new String(r);
         }
 
-        Expression parse_grouping(GroupingToken start, GroupingToken end) {
+        Expression parse_comment(GroupingToken start, GroupingToken? end) {
-            if ("'\"".Contains(start.value)) {
+            Debug.Assert(end != null);
+            Debug.Assert(";".Contains(start.value));
+            while (_sts.Available() > 0) {
+                Token<string> t = _sts.Get();
+                if (t.value == end.value) {
+                    break;
+                }
+            }
+            _sts.Commit();
+            return parse();
+        }
+
+        Expression parse_quote(GroupingToken start, GroupingToken? end) {
+            Debug.Assert(end == null);
+            Debug.Assert("'".Contains(start.value));
+            return Cons.FromList(new Expression[]{ new Symbol("quote"), parse()});
+        }
+
+        Expression parse_grouping(GroupingToken start, GroupingToken? end) {
+            if ("\"".Contains(start.value)) {
                 return parse_string(start, end);
             }
+            if ("'".Contains(start.value)) {
+                return parse_quote(start, end);
+            }
+            if (";".Contains(start.value)) {
+                return parse_comment(start, end);
+            }
+            Debug.Assert(end != null);
             IList<Expression> expressions = new List<Expression>();
             while (_sts.Available() > 0) {
                 Token<string> t = _sts.Get();
@@ -314,10 +77,17 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                     _sts.Commit();
                     break;
                 }
+                if (t is SpaceToken) {
+                    // need this here because those tokens can never
+                    // return an expression and trying to parse the last
+                    // expression will not work if its only spaces and a
+                    // closing parentheses.
+                    continue;
+                }
                 _sts.Rewind(1);
                 expressions.Add(parse());
             }
-            return new List(expressions);
+            return Cons.FromList(expressions);
         }
 
         Expression parse_atom(AtomToken at) {
@@ -327,27 +97,13 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                 return new Integer(parsed_value);
             }
             if (at.value.Equals("t")) {
-                return new Boolean(true);
+                return Boolean.TRUE;
             }
             if (at.value.Equals("nil")) {
-                return new Boolean(false);
+                return Boolean.FALSE;
             }
             _sts.Commit();
             return new Symbol(at.value);
         }
-
-        Expression parse_operator(OperatorToken ot) {
-            string v = ot.value;
-            while (_sts.Available() > 0) {
-                Token<string> t = _sts.Get();
-                if (t is OperatorToken ot_) {
-                    v += ot_.value;
-                    continue;
-                }
-                _sts.Rewind(1);
-                break;
-            }
-            return new Symbol(v);
-        }
     }
 }

Jellyfin.Plugin.SmartPlaylist/Lisp/Compiler/TokenStream.cs

@@ -24,11 +24,13 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
     class SpaceToken : Token<string> {
         private SpaceToken(string value) : base(value) {}
         private static IToken<string>? take(CharStream program) {
+            string spaces = " \n";
             if (program.Available() == 0) {
                 return null;
             }
-            if (program.Get() == ' ') {
+            var t = program.Get();
-                return new SpaceToken(" ");
+            if (spaces.Contains(t)) {
+                return new SpaceToken(t.ToString());
             }
             return null;
         }
@@ -41,7 +43,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                 return null;
             }
             char t = program.Get();
-            if ("()\"'".Contains(t)) {
+            if ("()\"';".Contains(t)) {
                 return new GroupingToken(t.ToString());
             }
             return null;
@@ -51,6 +53,10 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                 return new GroupingToken(")");
             } else if (_value == ")") {
                 return null;
+            } else if (_value == "'") {
+                return null;
+            } else if (_value == ";") {
+                return new GroupingToken("\n");
             }
             return new GroupingToken(_value);
         }
@@ -63,7 +69,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
             string value = "";
             while (program.Available() > 0) {
                 char t = program.Get();
-                if (!"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".Contains(t)) {
+                if (" \n()\"".Contains(t)) {
                     if (value.Equals("")) {
                         return null;
                     }
@@ -72,22 +78,10 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                 }
                 value += t;
             }
+            if (value.Equals("")) {
                 return null;
             }
-    }
+            return new AtomToken(value);
-
-    class OperatorToken : Token<string> {
-        private OperatorToken(string value) : base(value) {}
-        private static IToken<string>? take(CharStream program) {
-            if (program.Available() == 0) {
-                return null;
-            }
-            return new OperatorToken(program.Get().ToString());
-            //char t = program.get();
-            //if ("+-*/%".Contains(t)) {
-            //    return new OperatorToken(t.ToString());
-            //}
-            //return null;
         }
     }
 
@@ -101,7 +95,6 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
             typeof(SpaceToken),
             typeof(GroupingToken),
             typeof(AtomToken),
-            typeof(OperatorToken),
         };
         protected StringTokenStream(IList<Token<string>> tokens) : base(tokens) {}
         private static StringTokenStream generate(CharStream program) {
@@ -111,7 +104,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler {
                 if (prev_avail == program.Available() && prev_avail == 0) {
                     break;
                 } else if (prev_avail == program.Available()) {
-                    throw new ApplicationException("Program is invalid");
+                    throw new ApplicationException($"Program is invalid, still available: {program.Available()}");
                 }
                 prev_avail = program.Available();
                 foreach (Type c in _classes) {

Jellyfin.Plugin.SmartPlaylist/Lisp/Expression.cs

@@ -0,0 +1,344 @@
+namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
+    interface IAddable<T> where T : IAddable<T> {
+        static abstract T operator +(T left, T right);
+    }
+
+    interface ISubtractable<T> where T : ISubtractable<T> {
+        static abstract T operator -(T left, T right);
+    }
+
+    interface IMultiplicatable<T> where T : IMultiplicatable<T> {
+        static abstract T operator *(T left, T right);
+    }
+
+    interface IDivisible<T> where T : IDivisible<T> {
+        static abstract T operator /(T left, T right);
+        static abstract T operator %(T left, T right);
+    }
+
+    interface ISortable<T, E> where T : ISortable<T, E> {
+        static abstract E operator >(T left, T right);
+        static abstract E operator <(T left, T right);
+        static abstract E operator >=(T left, T right);
+        static abstract E operator <=(T left, T right);
+    }
+
+    interface IComparable<T, E> where T : IComparable<T, E> {
+        static abstract E operator ==(T left, T right);
+        static abstract E operator !=(T left, T right);
+        E Equals(T other);
+    }
+
+    interface IInner {
+        public object Inner();
+    }
+
+    public abstract class Expression: IComparable<Expression, bool> {
+        public override abstract string? ToString();
+        public abstract override int GetHashCode();
+        public abstract bool Equals(Expression other);
+        public override bool Equals(object? other) {
+            if (other is Expression other_e) {
+                return Equals(other_e);
+            }
+            return false;
+        }
+        public static bool operator ==(Expression left, Expression right) {
+            return left.Equals(right);
+        }
+        public static bool operator !=(Expression left, Expression right) {
+            return !left.Equals(right);
+        }
+    }
+
+    public abstract class Atom : Expression {}
+    public class Scalar<V> : Atom, IInner where V : notnull {
+        protected V _value;
+        public Scalar(V value) {
+            _value = value;
+        }
+        public override int GetHashCode() {
+            return 17 * 23 + _value.GetHashCode();
+        }
+        public override bool Equals(Expression other) {
+            if (other is Scalar<V> other_scalar) {
+                return _value.Equals(other_scalar._value);
+            }
+            return false;
+        }
+        public override string? ToString() {
+            return _value.ToString();
+        }
+        public V Value() {
+            return _value;
+        }
+        public object Inner() {
+            return _value;
+        }
+    }
+    public class Symbol : Atom {
+        private string _name;
+        public Symbol(string name) {
+            _name = name;
+        }
+        public override int GetHashCode() {
+            return 17 * 23 + _name.GetHashCode();
+        }
+        public override bool Equals(Expression other) {
+            if (other is Symbol other_symbol) {
+                return _name.Equals(other_symbol._name);
+            }
+            return false;
+        }
+        public override string? ToString() {
+            return _name.ToString();
+        }
+        public string Name() {
+            return _name;
+        }
+    }
+    public class Integer : Scalar<int>, IAddable<Integer>, ISubtractable<Integer>, IMultiplicatable<Integer>, IDivisible<Integer>, ISortable<Integer, Boolean> {
+        public Integer(int value) : base(value) {}
+        public static Integer operator +(Integer a, Integer b) {
+            return new Integer(a._value + b._value);
+        }
+        public static Integer operator -(Integer a, Integer b) {
+            return new Integer(a._value - b._value);
+        }
+        public static Integer operator *(Integer a, Integer b) {
+            return new Integer(a._value * b._value);
+        }
+        public static Integer operator /(Integer a, Integer b) {
+            return new Integer(a._value / b._value);
+        }
+        public static Integer operator %(Integer a, Integer b) {
+            return new Integer(a._value % b._value);
+        }
+        public static Boolean operator >(Integer a, Integer b) {
+            return (a._value > b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator <(Integer a, Integer b) {
+            return (a._value < b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator >=(Integer a, Integer b) {
+            return (a._value >= b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator <=(Integer a, Integer b) {
+            return (a._value <= b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public override int GetHashCode() {
+            return base.GetHashCode();
+        }
+        public override bool Equals(object? other) {
+            return base.Equals(other);
+        }
+        public static Boolean operator ==(Integer a, Integer b) {
+            return (a._value == b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator !=(Integer a, Integer b) {
+            return (a._value != b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+    }
+
+    public class Boolean: Scalar<bool> {
+        public static Boolean TRUE = new Boolean(true);
+        public static Boolean FALSE = new Boolean(false);
+        private Boolean(bool value) : base(value) {}
+        public override string? ToString() {
+            if (_value) {
+                return "t";
+            }
+            return "nil";
+        }
+        public IList<Expression> ToList() {
+            if (_value) {
+                throw new ApplicationException("Cannot use t as list");
+            }
+            return new List<Expression>();
+        }
+    }
+    public class String: Scalar<string>, ISortable<String, Boolean> {
+        public String(string value) : base(value) {}
+        public override string? ToString() {
+            return $"\"{base.ToString()}\"";
+        }
+        public static Boolean operator <(String a, String b) {
+            return (a.Value().CompareTo(b.Value()) < 0) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator >(String a, String b) {
+            return b < a;
+        }
+        public static Boolean operator <=(String a, String b) {
+            return (a.Value().CompareTo(b.Value()) <= 0) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator >=(String a, String b) {
+            return b <= a;
+        }
+        public override int GetHashCode() {
+            return base.GetHashCode();
+        }
+        public override bool Equals(object? other) {
+            return base.Equals(other);
+        }
+        public static Boolean operator ==(String a, String b) {
+            return (a._value == b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator !=(String a, String b) {
+            return (a._value != b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+    }
+    public class Cons: Expression {
+        public Expression Item1;
+        public Expression Item2;
+        public Cons(Expression item1, Expression item2) {
+            Item1 = item1;
+            Item2 = item2;
+        }
+        public static Expression FromList(IEnumerable<Expression> expressions) {
+            var e = expressions.ToList();
+            if (e.Count == 0) {
+                return Boolean.FALSE;
+            }
+            var item1 = expressions.First();
+            if (e.Count == 1) {
+                return new Cons(item1, Boolean.FALSE);
+            }
+            var item2 = expressions.Skip(1).ToList();
+            return new Cons(item1, FromList(item2));
+        }
+        public IEnumerable<Expression> ToList() {
+            var l = new List<Expression>();
+            l.Add(Item1);
+            if (Item2 == Boolean.FALSE) {
+                return l;
+            }
+            if (Item2 is Cons item2_cons) {
+                l.AddRange(item2_cons.ToList());
+                return l;
+            }
+            l.Add(Item2);
+            return l;
+        }
+        public override int GetHashCode() {
+            var hash = 17;
+            hash *= 23;
+            hash += Item1.GetHashCode();
+            hash *= 23;
+            hash += Item2.GetHashCode();
+            return hash;
+        }
+        public override bool Equals(Expression other) {
+            if (other is Cons other_list) {
+                return Item1.Equals(other_list.Item1) && Item2.Equals(other_list.Item2);
+            }
+            return false;
+        }
+        private string? ToStringSimple() {
+            if (Item2.Equals(Boolean.FALSE)) {
+                return Item1.ToString();
+            }
+            if (Item2 is Cons item2_cons) {
+                return $"{Item1} {item2_cons.ToStringSimple()}";
+            }
+            return $"{Item1} . {Item2}";
+        }
+        public override string? ToString() {
+            if (Item1 is Symbol SymbolItem1
+                    && SymbolItem1.Name() == "quote"
+                    && Item2 is Cons ConsItem2
+                    && ConsItem2.Item2.Equals(Boolean.FALSE)
+                    ) {
+                return $"'{ConsItem2.Item1}";
+            }
+            return $"({ToStringSimple()})";
+        }
+    }
+
+    public class Object : Scalar<object> {
+        internal Object(object value) : base(value) {}
+        public static Expression FromBase(object? o) {
+            if (o == null) {
+                return Boolean.FALSE;
+            }
+            switch (o) {
+                case bool b:
+                    return b ? Boolean.TRUE : Boolean.FALSE;
+                case int i:
+                    return new Integer(i);
+                case string s:
+                    return new String(s);
+                case Expression e:
+                    return e;
+                case IEnumerable<object> e:
+                    return Cons.FromList(e.Select(x => FromBase(x)));
+                default:
+                    return new Object(o);
+            }
+        }
+    }
+
+    public class Procedure : Expression {
+        private IEnumerable<Symbol> _parameters;
+        private Expression _body;
+        private bool _eval_args;
+        public Procedure(IEnumerable<Symbol> parameters, Expression body, bool eval_args) {
+            _parameters = parameters;
+            _body = body;
+            _eval_args = eval_args;
+        }
+        public override int GetHashCode() {
+            int hash = 17;
+            hash *= 23;
+            hash += _parameters.GetHashCode();
+            hash *= 23;
+            hash += _body.GetHashCode();
+            return hash;
+        }
+        public override bool Equals(Expression? other) {
+            if (other is Procedure other_p) {
+                return _parameters == other_p._parameters && _body == other_p._body;
+            }
+            return false;
+        }
+        public override string ToString() {
+            var star = _eval_args ? "" : "*";
+            return $"(lambda{star} {Cons.FromList(_parameters)} {_body})";
+        }
+
+        private Expression __eval(Executor e, Expression exp) {
+            if (!_eval_args) return exp;
+            return e.eval(exp);
+        }
+
+        private Expression _eval(Executor e, Expression exp) {
+            var r = __eval(e, exp);
+            //Console.WriteLine($"{exp} = {r}");
+            return r;
+        }
+
+        public Expression Call(Executor e, IList<Expression> args) {
+            Executor new_e = new Executor(new SubEnvironment(e.environment), e.builtins, e.builtinsLater);
+            var _params = _parameters.Select(x => x.Name()).ToArray();
+            var idx_rest = -1;
+
+            IList<(string, Expression)> name_args = new List<(string, Expression)>();
+            for (var i = 0; i < _parameters.Count(); i++) {
+                var name = _params[i];
+                if (name.Equals(".")) {
+                    idx_rest = i + 1;
+                    break;
+                }
+                name_args.Add((name, _eval(e, args[i])));
+            }
+            if (idx_rest > 0) {
+                name_args.Add((_params[idx_rest], Cons.FromList(args.Skip(idx_rest - 1).Select(x => _eval(e, x)))));
+            }
+            foreach (var na in name_args) {
+                new_e.environment.Set(na.Item1, na.Item2);
+            }
+            var r = new_e.eval(_body);
+            return r;
+        }
+    }
+
+}

Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs

@@ -3,63 +3,19 @@ using System.Reflection;
 using Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler;
 
 namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
-    using Function = Func<IList<Expression>, Expression>;
+    using Function = Func<IEnumerable<Expression>, Expression>;
-    using FunctionLater = Func<Executor, IList<Expression>, Expression>;
+    using FunctionLater = Func<Executor, IEnumerable<Expression>, Expression>;
-
-    public class Procedure : Expression {
-        private Compiler.List _parameters;
-        private Expression _body;
-        public Procedure(Compiler.List parameters, Expression body) {
-            _parameters = parameters;
-            _body = body;
-        }
-        private static IEnumerable<(T1, T2)> Zip<T1, T2>(IEnumerable<T1> a, IEnumerable<T2> b) {
-            using (var e1 = a.GetEnumerator()) using (var e2 = b.GetEnumerator()) {
-                while (e1.MoveNext() && e2.MoveNext()) {
-                    yield return (e1.Current, e2.Current);
-                }
-            }
-        }
-        public override int GetHashCode() {
-            int hash = 17;
-            hash *= 23;
-            hash += _parameters.GetHashCode();
-            hash *= 23;
-            hash += _body.GetHashCode();
-            return hash;
-        }
-        public override bool Equals(Expression? other) {
-            if (other is Procedure other_p) {
-                return _parameters == other_p._parameters && _body == other_p._body;
-            }
-            return false;
-        }
-        public override object Inner() {
-            throw new ApplicationException("This is not sensible");
-        }
-        public override string ToString() {
-            return $"(lambda {_parameters} {_body})";
-        }
-
-        public Expression Call(Executor e, IList<Expression> args) {
-            var p = _parameters.expressions.Select(x => x.Inner().ToString()).ToList();
-            Executor new_e = new Executor(new SubEnvironment(e.environment), e.builtins, e.builtinsLater);
-            foreach (var tuple in Zip<string, Expression>(p, args)) {
-                new_e.environment.Set(tuple.Item1, tuple.Item2);
-            }
-            return new_e.eval(_body);
-        }
-    }
 
     public interface IEnvironment<K, V> {
-        public V Get(K k);
+        public V? Get(K k);
         public void Set(K k, V v);
         public IEnvironment<K, V>? Find(K k);
+        public IEnvironment<K, V> Parent(bool recursive);
     }
 
     public class Environment : Dictionary<string, Expression>, IEnvironment<string, Expression> {
         public Expression? Get(string k) {
-            if (TryGetValue(k, out Expression v)) {
+            if (TryGetValue(k, out Expression? v)) {
                 return v;
             }
             return null;
@@ -74,11 +30,71 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             }
             return null;
         }
+
+        public IEnvironment<string, Expression> Parent(bool recursive) {
+            return this;
+        }
     }
 
     public class DefaultEnvironment: Environment {
         public DefaultEnvironment() {
-            this["find"] = new Parser("(lambda (item list) (if (= list ()) nil (if (= item (car list)) (car list) (find item (cdr list)))))").parse();
+            var e = new Executor();
+            this["null"] = new Symbol("not");
+            this["list"] = e.eval("(lambda (. args) args)");
+            this["find"] = e.eval("(lambda (item list_) (if (null list_) nil (if (= item (car list_)) (car list_) (find item (cdr list_)))))");
+            this["map"] = e.eval("(lambda (fc l) (if (null l) nil (cons (fc (car l)) (map fc (cdr l)))))");
+            this["fold"] = e.eval("(lambda (fc i l) (if (null l) i (fold fc (fc i (car l)) (cdr l))))");
+            this["any"] = e.eval("(lambda (fc l) (apply or (map fc l)))");
+            this["all"] = e.eval("(lambda (fc l) (apply and (map fc l)))");
+            this["append"] = e.eval("(lambda (l i) (if (null l) i (cons (car l) (append (cdr l) i))))");
+            this["qsort"] = e.eval(
+                """
+                (lambda
+                  (fc list00)
+                  (let
+                    (getpivot
+                      (lambda
+                        (list0)
+                        (car list0)))
+                    (split
+                      (lambda
+                        (list0 pivot fc h0 h1)
+                        (cond
+                          ((null list0) (list list0 pivot fc h0 h1))
+                          ((fc (car list0) pivot) (split (cdr list0) pivot fc h0 (cons (car list0) h1)))
+                          (t (split (cdr list0) pivot fc (cons (car list0) h0) h1)))))
+                    (sort
+                      (lambda
+                        (fc list0)
+                        (cond
+                          ((null list0) nil)
+                          ((null (cdr list0)) list0)
+                          (t
+                            (let*
+                              (halves (split list0 (getpivot list0) fc nil nil))
+                              (h0 (car (cdr (cdr (cdr halves)))))
+                              (h1 (car (cdr (cdr (cdr (cdr halves))))))
+                              (append (sort fc h0) (sort fc h1)))))))
+                    (sort fc list00)))
+                """
+            );
+            this["rand"] = e.eval(
+                """
+                (lambda
+                  (. a)
+                  (cond
+                    ((null a) (random))
+                    ((null (cdr a)) (% (random) (car a)))
+                    (t (+
+                         (car a)
+                         (%
+                           (random)
+                           (-
+                             (car (cdr a))
+                             (car a)))))))
+                """
+            );
+            this["shuf"] = new Symbol("shuffle");
         }
     }
 
@@ -88,7 +104,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             _super = super;
         }
         public Expression? Get(string k) {
-            if (TryGetValue(k, out Expression v)) {
+            if (TryGetValue(k, out Expression? v)) {
                 return v;
             }
             return null;
@@ -103,272 +119,349 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             }
             return _super.Find(k);
         }
+
+        public IEnvironment<string, Expression> Parent(bool recursive) {
+            if (recursive) {
+                return this._super.Parent(recursive);
+            }
+            return this._super;
+        }
     }
 
     public class Builtins : Dictionary<string, Function> {
+
+        private static Dictionary<string, Type?> ResolvedTypes = new Dictionary<string, Type?>();
+        private Random Random;
+
         public Builtins() : base() {
-            this["+"] = _add;
+            Random = new Random();
-            this["-"] = _sub;
+            this["atom"] = _atom;
-            this["*"] = _mul;
+            this["eq"] = _eq;
-            this["/"] = _div;
-            this["%"] = _mod;
-            this[">"] = _gt;
-            this["<"] = _lt;
-            this[">="] = _ge;
-            this["<="] = _le;
-            this["eq?"] = _eq;
-            this["="] = _eq;
-            this["!="] = _ne;
-            this["abs"] = _abs;
-            this["append"] = _append;
-            this["begin"] = _begin;
             this["car"] = _car;
             this["cdr"] = _cdr;
             this["cons"] = _cons;
-            this["not"] = _not;
+
-            this["length"] = _length;
+            this["begin"] = _begin;
+
+            this["+"] = (x) => _agg((Integer a, Integer b) => a + b, x);
+            this["-"] = (x) => _agg((Integer a, Integer b) => a - b, x);
+            this["*"] = (x) => _agg((Integer a, Integer b) => a * b, x);
+            this["/"] = (x) => _agg((Integer a, Integer b) => a / b, x);
+            this["%"] = (x) => _agg((Integer a, Integer b) => a % b, x);
+
+            this["="] = (x) => _cmp((Atom a, Atom b) => (a == b)? Boolean.TRUE : Boolean.FALSE, x);
+            this["!="] = (x) => _cmp((Atom a, Atom b) => (a != b)? Boolean.TRUE : Boolean.FALSE, x);
+            this["<"] = (x) => _cmp((Integer a, Integer b) => a < b, x);
+            this["<="] = (x) => _cmp((Integer a, Integer b) => a <= b, x);
+            this[">"] = (x) => _cmp((Integer a, Integer b) => a > b, x);
+            this[">="] = (x) => _cmp((Integer a, Integer b) => a >= b, x);
+            this["not"] = (x) => {
+                return (x.First() == Boolean.FALSE) ? Boolean.TRUE : Boolean.FALSE;
+            };
+            this["string="] = (x) => _cmp((String a, String b) => a == b, x);
+            this["string!="] = (x) => _cmp((String a, String b) => a != b, x);
+            this["string>"] = (x) => _cmp((String a, String b) => a > b, x);
+            this["string>="] = (x) => _cmp((String a, String b) => a >= b, x);
+            this["string<"] = (x) => _cmp((String a, String b) => a < b, x);
+            this["string<="] = (x) => _cmp((String a, String b) => a <= b, x);
+
             this["haskeys"] = _haskeys;
             this["getitems"] = _getitems;
             this["invoke"] = _invoke;
-        }
+            this["invoke-generic"] = _invoke_generic;
 
-        private static T _agg<T>(Func<T, T, T> op, IList<T> args) {
+            this["random"] = (x) => new Lisp.Integer(Random.Next());
-            T agg = args[0];
+            this["shuffle"] = (x) => {
+                var newx = ((Lisp.Cons) x.First()).ToList().ToArray();
+                Random.Shuffle<Expression>(newx);
+                return Lisp.Cons.FromList(newx);
+            };
+        }
+        private static T _agg<T>(Func<T, T, T> op, IEnumerable<Expression> args) where T : Expression {
+            T agg = (T) args.First();
             foreach (var arg in args.Skip(1)) {
-                agg = op(agg, arg);
+                var arg_ = (T) arg;
+                agg = op(agg, arg_);
             }
             return agg;
         }
-        private static Expression _add(IList<Expression> args) {
+        private static E _cmp<T, E>(Func<T, T, E> op, IEnumerable<Expression> args) where T : Expression where E : Expression {
-            Expression first = args[0];
+            return op((T) args.First(), (T) args.Skip(1).First());
-            switch (first) {
-                case Integer i:
-                    return _agg((a, b) => a + b, args.Select(x => (Integer) x).ToList());
-                case Compiler.String s:
-                    return _agg((a, b) => a + b, args.Select(x => (Compiler.String) x).ToList());
         }
-            throw new ApplicationException();
+        private static Expression _atom(IEnumerable<Expression> args) {
+            return (args.First() is Atom) ? Boolean.TRUE : Boolean.FALSE;
         }
-        private static Expression _sub(IList<Expression> args) {
+        private static Expression _eq(IEnumerable<Expression> args) {
-            Expression first = args[0];
+            return args.First().Equals(args.Skip(1).First()) ? Boolean.TRUE : Boolean.FALSE;
-            switch (first) {
-                case Integer i:
-                    return _agg((a, b) => a - b, args.Select(x => (Integer) x).ToList());
         }
-            throw new ApplicationException();
+        private static Expression _car(IEnumerable<Expression> args) {
+            return ((Cons)args.First()).Item1;
         }
-        private static Expression _mul(IList<Expression> args) {
+        private static Expression _cdr(IEnumerable<Expression> args) {
-            Expression first = args[0];
+            return ((Cons)args.First()).Item2;
-            switch (first) {
-                case Integer i:
-                    return _agg((a, b) => a * b, args.Select(x => (Integer) x).ToList());
         }
-            throw new ApplicationException();
+        private static Expression _cons(IEnumerable<Expression> args) {
+            return new Cons(args.First(), args.Skip(1).First());
         }
-        private static Expression _div(IList<Expression> args) {
+        private static Expression _begin(IEnumerable<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _agg((a, b) => a / b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _mod(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _agg((a, b) => a % b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static E _cmp<T, E>(Func<T, T, E> op, IList<T> args) {
-            T first = args[0];
-            T second = args[1];
-            return op(first, second);
-        }
-        private static Expression _gt(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _cmp((a, b) => a > b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _lt(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _cmp((a, b) => a < b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _ge(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _cmp((a, b) => a >= b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _le(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return _cmp((a, b) => a <= b, args.Select(x => (Integer) x).ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _eq(IList<Expression> args) {
-            bool r = _cmp((a, b) => a == b, args);
-            return new Compiler.Boolean(r);
-        }
-        private static Expression _ne(IList<Expression> args) {
-            bool r = _cmp((a, b) => a != b, args);
-            return new Compiler.Boolean(r);
-        }
-        private static Expression _abs(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case Integer i:
-                    return i.value >= 0 ? i : new Integer(-i.value);
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _append(IList<Expression> args) {
-            Expression first = args[0];
-            switch (first) {
-                case List l:
-                    return l + new List(args);
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _begin(IList<Expression> args) {
             return args.Last();
         }
-        private static Expression _car(IList<Expression> args) {
+        private static Expression _haskeys(IEnumerable<Expression> args) {
-            return ((List) args.First()).expressions.First();
+            Object o = new Object(((IInner) args.First()).Inner());
-        }
-        private static Expression _cdr(IList<Expression> args) {
-            return new List(((List) args.First()).expressions.Skip(1).ToList());
-        }
-        private static Expression _cons(IList<Expression> args) {
-            switch (args[1]) {
-                case Compiler.List other_list:
-                    return (new Compiler.List(new []{args[0]}.ToList()) + new Compiler.List(other_list.expressions));
-                case Atom other_atom:
-                    return new Compiler.List(new[]{args[0], args[1]}.ToList());
-            }
-            throw new ApplicationException();
-        }
-        private static Expression _not(IList<Expression> args) {
-            if (args[0] == new Compiler.Boolean(false)) {
-                return new Compiler.Boolean(true);
-            }
-            return new Compiler.Boolean(false);
-        }
-        private static Expression _length(IList<Expression> args) {
-            return new Integer(((Compiler.List)args[0]).expressions.Count());
-        }
-        private static Expression _haskeys(IList<Expression> args) {
-            Compiler.Object o = (Compiler.Object) args[0];
             foreach (var e in args.Skip(1)) {
-                Compiler.String s = (Compiler.String) e;
+                String s = (String) e;
-                PropertyInfo? pi = o.value.GetType().GetProperty(s.value);
+                PropertyInfo? pi = o.Value().GetType().GetProperty(s.Value());
                 if (pi != null) {
                     continue;
                 }
-                MethodInfo? mi = o.value.GetType().GetMethod(s.value);
+                MethodInfo? mi = o.Value().GetType().GetMethod(s.Value());
                 if (mi != null) {
                     continue;
                 }
-                FieldInfo? fi = o.value.GetType().GetField(s.value);
+                FieldInfo? fi = o.Value().GetType().GetField(s.Value());
                 if (fi != null) {
                     continue;
                 }
-                return new Compiler.Boolean(false);
+                return Boolean.FALSE;
             }
-            return new Compiler.Boolean(true);
+            return Boolean.TRUE;
         }
-        private static Expression _getitems(IList<Expression> args) {
+        private static Expression _getitems(IEnumerable<Expression> args) {
-            Compiler.Object o = (Compiler.Object) args[0];
+            Object o = new Object(((IInner) args.First()).Inner());
             IList<Expression> r = new List<Expression>();
             foreach (var e in args.Skip(1)) {
-                Compiler.String s = (Compiler.String) e;
+                String s = (String) e;
-                PropertyInfo? pi = o.value.GetType().GetProperty(s.value);
+                PropertyInfo? pi = o.Value().GetType().GetProperty(s.Value());
                 if (pi != null) {
-                    r.Add(Compiler.Object.FromBase(pi.GetValue(o.value)));
+                    r.Add(Object.FromBase(pi.GetValue(o.Value())));
                     continue;
                 }
-                FieldInfo? fi = o.value.GetType().GetField(s.value);
+                FieldInfo? fi = o.Value().GetType().GetField(s.Value());
                 if (fi != null) {
-                    r.Add(Compiler.Object.FromBase(fi.GetValue(o.value)));
+                    r.Add(Object.FromBase(fi.GetValue(o.Value())));
                     continue;
                 }
-                throw new ApplicationException($"{o.value} has no property or field {s.value}");
+                throw new ApplicationException($"{o.Value()} has no property or field {s.Value()}");
             }
-            return new Compiler.List(r);
+            return Cons.FromList(r);
         }
 
-        private static Expression _invoke(IList<Expression> args) {
+        private static Expression _invoke(IEnumerable<Expression> args) {
-            Compiler.Object o = (Compiler.Object) args[0];
+            Object o = new Object(((IInner) args.First()).Inner());
-            Compiler.String s = (Compiler.String) args[1];
+            String s = (String) args.Skip(1).First();
-            Compiler.List l = (Compiler.List) args[2];
+            IEnumerable<Expression> l;
-            IList<Expression> r = new List<Expression>();
+            if (args.Skip(2).First() is Boolean lb && lb == Boolean.FALSE) {
-            MethodInfo? mi = o.value.GetType().GetMethod(s.value);
+                l = new List<Expression>();
-            if (mi == null) {
+            } else if (args.Skip(2).First() is Cons lc) {
-                throw new ApplicationException($"{o.value} has not method {s.value}");
+                l = lc.ToList();
+            } else {
+                throw new ApplicationException($"Expected a list of arguments, got {args.Skip(2).First()}");
             }
-            return Compiler.Object.FromBase(mi.Invoke(o.value, (object?[]?) l.Inner()));
+            object[]? l_ = l.Select<Expression, object>(x => {
+                switch (x) {
+                    case Integer s:
+                        return s.Value();
+                    case Boolean b:
+                        return b.Value();
+                    case String s:
+                        return s.Value();
+                    case Object o:
+                        return o.Value();
+                    case Cons c:
+                        return c.ToList().ToList();
+                }
+                throw new ApplicationException($"Unhandled value {x} (type {x.GetType()})");
+            }).ToArray();
+            Type[] l_types = l_.Select( x => {
+                    return x.GetType();
+            }).ToArray();
+
+            IList<Expression> r = new List<Expression>();
+            MethodInfo? mi = o.Value().GetType().GetMethod(s.Value(), l_types);
+            if (mi == null) {
+                throw new ApplicationException($"{o.Value()} has no method {s.Value()}");
+            }
+
+            return Object.FromBase(mi.Invoke(o.Value(), l_));
+        }
+
+        private static Type? GetType(string name) {
+            if (ResolvedTypes.ContainsKey(name)) {
+                return ResolvedTypes[name];
+            }
+            var t = Type.GetType(
+                name,
+                (name) => { return AppDomain.CurrentDomain.GetAssemblies().Where(z => (z.FullName != null) && z.FullName.StartsWith(name.FullName)).FirstOrDefault(); },
+                null,
+                true
+            );
+            ResolvedTypes[name] = t;
+            return t;
+        }
+
+        private static Expression _invoke_generic(IEnumerable<Expression> args) {
+            Object o = new Object(((IInner) args.First()).Inner());
+            String s = (String) args.Skip(1).First();
+            IEnumerable<Expression> l;
+            if (args.Skip(2).First() is Boolean lb && lb == Boolean.FALSE) {
+                l = new List<Expression>();
+            } else if (args.Skip(2).First() is Cons lc) {
+                l = lc.ToList();
+            } else {
+                throw new ApplicationException($"Expected a list of arguments, got {args.Skip(2).First()}");
+            }
+            IEnumerable<Type> types;
+            if (args.Skip(3).First() is Boolean lb_ && lb_ == Boolean.FALSE) {
+                types = new List<Type>();
+            } else if (args.Skip(3).First() is Cons lc) {
+                types = lc.ToList().Select(x => GetType(((String) x).Value())).ToList();
+            } else {
+                throw new ApplicationException($"Expected a list of arguments, got {args.Skip(3).First()}");
+            }
+            object[]? l_ = l.Select<Expression, object>(x => {
+                switch (x) {
+                    case Integer s:
+                        return s.Value();
+                    case Boolean b:
+                        return b.Value();
+                    case String s:
+                        return s.Value();
+                    case Object o:
+                        return o.Value();
+                    case Cons c:
+                        return c.ToList().ToList();
+                }
+                throw new ApplicationException($"Unhandled value {x} (type {x.GetType()})");
+            }).ToArray();
+            Type[] l_types = l_.Select( x => {
+                    return x.GetType();
+            }).ToArray();
+
+            IList<Expression> r = new List<Expression>();
+            MethodInfo? mi = o.Value().GetType().GetMethod(s.Value(), l_types);
+            if (mi == null) {
+                throw new ApplicationException($"{o.Value()} has no method {s.Value()}");
+            }
+            mi = mi.MakeGenericMethod(types.ToArray());
+
+            return Object.FromBase(mi.Invoke(o.Value(), l_));
         }
     }
 
     public class BuiltinsLater : Dictionary<string, FunctionLater> {
         public BuiltinsLater() : base() {
+            this["quote"] = _quote;
+            this["eval"] = _eval;
+            this["cond"] = _cond;
             this["if"] = _if;
             this["define"] = _define;
+            this["let"] = _let;
+            this["let*"] = _let_star;
             this["lambda"] = _lambda;
+            this["lambda*"] = _lambda_star;
             this["apply"] = _apply;
-            this["and"] = _and;
+
-            this["or"] = _or;
+            this["and"] = (e, x) => {
+                Expression? r = null;
+                foreach (var xi in x) {
+                    r = e.eval(xi);
+                    if (r == Boolean.FALSE) {
+                        return r;
                     }
-        private static Expression _if(Executor e, IList<Expression> args) {
-            bool test = e.eval(args[0]) != (new Compiler.Boolean(false));
-            return e.eval(args[1 + (test ? 0 : 1)]);
                 }
-        private static Expression _define(Executor e, IList<Expression> args) {
+                if (r is null) {
-            var refname = ((Symbol) args[0]).name;
+                    return Boolean.FALSE;
-            e.environment.Set(refname, e.eval(args[1]));
-            return new Compiler.Boolean(false); // NOOP
                 }
-        private static Expression _lambda(Executor e, IList<Expression> args) {
+                return r;
-            return new Procedure((Compiler.List) args[0], args[1]);
+            };
+            this["or"] = (e, x) => {
+                foreach (var xi in x) {
+                    var r = e.eval(xi);
+                    if (r != Boolean.FALSE) {
+                        return r;
                     }
-        private static Expression _apply(Executor e, IList<Expression> args) {
-            if (args[0].GetType() != typeof(Symbol)) {
-                throw new ApplicationException();
                 }
-            if (args[1].GetType() != typeof(List)) {
+                return Boolean.FALSE;
-                throw new ApplicationException();
+            };
         }
-            Symbol arg0 = (Compiler.Symbol) args[0];
+        private static Expression _quote(Executor e, IEnumerable<Expression> args) {
-            Compiler.List other_args = (Compiler.List) args[1];
+            return args.First();
-            return e.EvalFunction(arg0, other_args.expressions);
         }
-        private static Expression _and(Executor e, IList<Expression> args) {
+        private static Expression _eval(Executor e, IEnumerable<Expression> args) {
-            Expression result = new Compiler.Boolean(false);
+            return e.eval(e.eval(args.First()));
-            foreach (var exp in args) {
-                result = e.eval(exp);
-                if (result == new Compiler.Boolean(false)) { return result; }
         }
-            return result;
+        private static Expression _cond(Executor e, IEnumerable<Expression> args) {
+            foreach (var a in args) {
+                if (a is Cons a_cons) {
+                    var a_ = a_cons.ToList();
+                    if (!e.eval(a_.First()).Equals(Boolean.FALSE)) {
+                        return e.eval(a_.Skip(1).First());
                     }
-        private static Expression _or(Executor e, IList<Expression> args) {
+                } else {
-            Expression result = new Compiler.Boolean(false);
+                    throw new ApplicationException($"Incorrect arguments to cond, expected list: {args}");
-            foreach (var exp in args) {
-                result = e.eval(exp);
-                if (result != new Compiler.Boolean(false)) { return result; }
                 }
-            return result;
+            }
+            return Boolean.FALSE;
+        }
+        private static Expression _if(Executor e, IEnumerable<Expression> args) {
+            if (e.eval(args.First()).Equals(Boolean.FALSE)) {
+                return e.eval(args.Skip(2).First());
+            }
+            return e.eval(args.Skip(1).First());
+        }
+        private static Expression _define(Executor e, IEnumerable<Expression> args) {
+            Symbol refname = (Symbol) args.First();
+            e.environment.Parent(true).Set(refname.Name(), args.Skip(1).Select(x => e.eval(x)).First());
+            return Boolean.TRUE;
+        }
+        private static Expression _let_star(Executor e, IEnumerable<Expression> args) {
+            Executor new_e = new Executor(new SubEnvironment(e.environment), e.builtins, e.builtinsLater);
+            foreach (var pair in args.SkipLast(1)) {
+                if (pair is not Cons pair_cons) {
+                    throw new ApplicationException("No expression for let*");
+                }
+                Symbol refname = (Symbol) pair_cons.Item1;
+                Expression exp = ((Cons) pair_cons.Item2).Item1;
+                new_e.environment.Set(refname.Name(), new_e.eval(exp));
+            }
+            return new_e.eval(args.Last());
+        }
+        private static Expression _let(Executor e, IEnumerable<Expression> args) {
+            Executor new_e = new Executor(new SubEnvironment(e.environment), e.builtins, e.builtinsLater);
+            List<(Symbol, Expression)> vars = new List<(Symbol, Expression)>();
+            foreach (var pair in args.SkipLast(1)) {
+                if (pair is not Cons pair_cons) {
+                    throw new ApplicationException("");
+                }
+                Symbol refname = (Symbol) pair_cons.Item1;
+                Expression exp_ = ((Cons) pair_cons.Item2).Item1;
+                vars.Add((refname, e.eval(exp_)));
+            }
+            foreach (var pair in vars) {
+                new_e.environment.Set(pair.Item1.Name(), pair.Item2);
+            }
+            return new_e.eval(args.Last());
+        }
+        private static Expression _lambda(Executor e, IEnumerable<Expression> args) {
+            IEnumerable<Symbol> proc_args;
+            if (args.First() is Cons proc_args_) { proc_args = proc_args_.ToList().Select(x => (Symbol) x); }
+            else if (args.First() == Boolean.FALSE) { proc_args = new List<Symbol>(); }
+            else {
+                throw new ApplicationException("");
+            }
+            return new Procedure(proc_args, args.Skip(1).First(), true);
+        }
+        private static Expression _lambda_star(Executor e, IEnumerable<Expression> args) {
+            IEnumerable<Symbol> proc_args;
+            if (args.First() is Cons proc_args_) { proc_args = proc_args_.ToList().Select(x => (Symbol) x); }
+            else if (args.First() == Boolean.FALSE) { proc_args = new List<Symbol>(); }
+            else {
+                throw new ApplicationException("");
+            }
+            return new Procedure(proc_args, args.Skip(1).First(), false);
+        }
+        private static Expression _apply(Executor e, IEnumerable<Expression> args) {
+            return e.eval(new Cons(args.First(), e.eval(args.Skip(1).First())));
         }
     }
 
@@ -396,54 +489,55 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
         public Builtins builtins { get => _builtins; }
         public BuiltinsLater builtinsLater { get => _builtinsLater; }
 
-        public Expression EvalFunction(Symbol fcname, IList<Expression> args) {
+        public Expression? EvalFunction(Symbol fcname, IEnumerable<Expression> args) {
-            if (_environment.Find(fcname.name) is IEnvironment<string, Expression> _e) {
+            if (builtins.ContainsKey(fcname.Name())) {
-                Expression? first = _e.Get(fcname.name);
+                return builtins[fcname.Name()](args.Select(x => eval(x)).ToList()); // call ToList for sideeffect
-                return new List(new []{first}.ToList()) + new List(args.Select(x => eval(x)).ToList());
             }
-            if (_builtins.ContainsKey(fcname.name)) {
+            if (builtinsLater.ContainsKey(fcname.Name())) {
-                Function fc = _builtins[fcname.name];
+                return builtinsLater[fcname.Name()](this, args);
-                return fc(args.Select(x => eval(x)).ToList());
             }
-            if (_builtinsLater.ContainsKey(fcname.name)) {
+            return null;
-                FunctionLater fc = _builtinsLater[fcname.name];
-                return fc(this, args);
-            }
-            throw new ApplicationException($"Key '{fcname.name}' not found in environment or builtins");
-
         }
 
         public Expression eval(Expression expression) {
             switch (expression) {
                 case Symbol s:
-                    return _environment.Find(s.name).Get(s.name);
+                    if (_environment.Find(s.Name()) is not IEnvironment<string, Expression> env) {
-                case Compiler.Boolean b:
+                        if (builtins.ContainsKey(s.Name()) || builtinsLater.ContainsKey(s.Name())) {
+                            return s;
+                        }
+                        throw new ApplicationException($"Could not find '{s.Name()}'");
+                    }
+                    var r_ = env.Get(s.Name());
+                    if (r_ is null) {
+                        throw new ApplicationException($"Could not find '{s.Name()}'");
+                    }
+                    return r_;
+                case Boolean b:
                     return b;
                 case Integer i:
                     return i;
-                case Compiler.String s:
+                case String s:
                     return s;
-                case Compiler.Object o:
+                case Object o:
                     return o;
                 case Procedure p:
                     return p;
-                case List list:
+                case Cons cons:
-                    if (list.expressions.Count == 0) {
+                    var l = cons.ToList();
-                        return list;
+                    if (cons.Item1 is Symbol cons_item1_symbol) {
+                        Expression? r = EvalFunction(cons_item1_symbol, l.Skip(1));
+                        if (r is not null) { return r; }
                     }
-                    // do we really want to allow shadowing of builtins?
+                    var eval_Item1 = eval(cons.Item1);
-                    if (list.expressions[0].GetType() == typeof(Symbol)) {
+                    if (eval_Item1 is Symbol eval_item1_symbol1) {
-                        return eval(EvalFunction((Symbol) list.expressions[0], list.expressions.Skip(1).ToList()));
+                        Expression? r = EvalFunction(eval_item1_symbol1, l.Skip(1));
+                        if (r is not null) { return r; }
                     }
-                    if (list.expressions[0].GetType() == typeof(Procedure)) {
+                    if (eval_Item1 is Procedure eval_item1_procedure) {
-                        Procedure procedure = (Procedure) list.expressions[0];
+                        return eval_item1_procedure.Call(this, l.Skip(1).Select(x => x).ToList());
-                        return eval(procedure.Call(this, list.expressions.Skip(1).ToList()));
                     }
-                    var l = new List(list.expressions.Select(x => eval(x)).ToList());
+                    throw new ApplicationException($"Not handled case (type = {eval_Item1.GetType()}) '{cons}'");
-                    if (l.expressions[0].GetType() == typeof(Procedure)) {
-                        return eval(l);
-                    }
-                    return l;
             }
             throw new ApplicationException($"Not handled case '{expression}'");
         }

Jellyfin.Plugin.SmartPlaylist/Plugin.cs

@@ -1,18 +1,24 @@
-using System;
-using System.Collections.Generic;
 using System.Globalization;
 using MediaBrowser.Common.Configuration;
 using MediaBrowser.Common.Plugins;
 using MediaBrowser.Model.Plugins;
 using MediaBrowser.Model.Serialization;
+using MediaBrowser.Controller;
+using MediaBrowser.Controller.Library;
 
 namespace Jellyfin.Plugin.SmartPlaylist {
     public class Plugin : BasePlugin<PluginConfiguration>, IHasWebPages {
+        public IServerApplicationPaths ServerApplicationPaths;
+        public IUserManager UserManager;
         public Plugin(
             IApplicationPaths applicationPaths,
-            IXmlSerializer xmlSerializer
+            IXmlSerializer xmlSerializer,
+            IServerApplicationPaths serverApplicationPaths,
+            IUserManager userManager
         ) : base (applicationPaths, xmlSerializer) {
             Instance = this;
+            ServerApplicationPaths = serverApplicationPaths;
+            UserManager = userManager;
         }
         public static Plugin? Instance {get; private set; }
         public override string Name => "Smart Playlist";

Jellyfin.Plugin.SmartPlaylist/PluginConfiguration.cs

@@ -1,14 +1,72 @@
-using System;
-using System.Collections.Generic;
-using MediaBrowser.Common.Configuration;
-using MediaBrowser.Common.Plugins;
 using MediaBrowser.Model.Plugins;
-using MediaBrowser.Model.Serialization;
+using MediaBrowser.Controller;
 
 namespace Jellyfin.Plugin.SmartPlaylist {
     public class PluginConfiguration : BasePluginConfiguration {
-        public PluginConfiguration(
+        public PluginConfiguration() {
-        ) {
+            InitialProgram = """
+            (begin
+              (define lower
+                (lambda (s)
+                  (invoke s "ToLower" nil)))
+              (define is-genre
+                (lambda (g g-list)
+                  (any
+                    (lambda (x)
+                      (invoke (lower x) "Contains" (list (lower g))))
+                    g-list)))
+              (define is-genre-exact
+                (lambda (g g-list)
+                  (find g g-list)))
+              (define genre-list
+                (lambda nil
+                  (let
+                    (_g (getitems *item* "Genres"))
+                    (if (null _g)
+                      nil
+                      (car _g)))))
+              (define is-favorite
+                (lambda nil
+                  (invoke *item* "IsFavoriteOrLiked" (list *user*))))
+              (define is-type
+                (lambda (x)
+                  (and
+                    (haskeys *item* "GetClientTypeName")
+                    (invoke (invoke *item* "GetClientTypeName" nil) "Equals" (list x)))))
+              (define name-contains
+                (lambda (x)
+                  (invoke (lower (car (getitems *item* "Name"))) "Contains" (list (lower x)))))
+              (define is-favourite is-favorite)
+              (define all-genres (lambda (want have) (all (lambda (x) (is-genre x have)) want)))
+              (define any-genres (lambda (want have) (any (lambda (x) (is-genre x have)) want)))
+              (define get-name (lambda (x) (car (getitems x "Name"))))
+              (define find-parent (lambda (typename) (invoke-generic *item* "FindParent" nil (list typename))))
+              (define find-artist (lambda nil (find-parent "MediaBrowser.Controller.Entities.Audio.MusicArtist, MediaBrowser.Controller"))))
+            """;
+            store = new Store(new SmartPlaylistFileSystem(Plugin.Instance.ServerApplicationPaths));
+        }
+        private Store store { get; set; }
+        public string InitialProgram { get; set; }
+        public SmartPlaylistDto[] Playlists {
+            get {
+                return store.GetAllSmartPlaylistsAsync().GetAwaiter().GetResult();
+            }
+            set {
+                var existing = store.GetAllSmartPlaylistsAsync().GetAwaiter().GetResult().Select(x => x.Id).ToList();
+                foreach (var p in value) {
+                    existing.Remove(p.Id);
+                    store.SaveSmartPlaylistAsync(p).GetAwaiter().GetResult();
+                }
+                foreach (var p in existing) {
+                    store.DeleteSmartPlaylistById(p);
+                }
+            }
+        }
+        public object[][] Users {
+            get {
+                return Plugin.Instance.UserManager.Users.Select(x => new object[]{x.Id, x.Username}).ToArray();
+            }
+            set { }
         }
     }
 }

Jellyfin.Plugin.SmartPlaylist/ScheduledTasks/GeneratePlaylist.cs

@@ -1,3 +1,4 @@
+using System.Globalization;
 using MediaBrowser.Model.Tasks;
 using Microsoft.Extensions.Logging;
 using MediaBrowser.Controller;
@@ -5,28 +6,16 @@ using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.Playlists;
 using MediaBrowser.Controller.Providers;
 using MediaBrowser.Model.IO;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading;
-using System.Threading.Tasks;
 using Jellyfin.Data.Entities;
 using Jellyfin.Data.Enums;
 using MediaBrowser.Model.Entities;
-using MediaBrowser.Controller;
 using MediaBrowser.Controller.Entities;
-using MediaBrowser.Controller.Library;
-using MediaBrowser.Controller.Playlists;
-using MediaBrowser.Controller.Providers;
-using MediaBrowser.Model.IO;
 using MediaBrowser.Model.Playlists;
-using MediaBrowser.Model.Tasks;
-using Microsoft.Extensions.Logging;
 
 using Jellyfin.Plugin.SmartPlaylist.Lisp;
 using Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler;
-using Lisp_Object = Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler.Object;
+using Lisp_Object = Jellyfin.Plugin.SmartPlaylist.Lisp.Object;
-using Lisp_Boolean = Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler.Boolean;
+using Lisp_Boolean = Jellyfin.Plugin.SmartPlaylist.Lisp.Boolean;
 
 
 namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
@@ -93,7 +82,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
             }
         }
 
-        private SmartPlaylistId CreateNewPlaylist(string name, UserId userId) {
+        private PlaylistId CreateNewPlaylist(string name, UserId userId) {
             _logger.LogDebug("Creating playlist '{0}'", name);
             var req = new PlaylistCreationRequest {
                 Name = name,
@@ -105,21 +94,66 @@ namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
             return playlistGuid;
         }
 
+        private Executor SetupExecutor() {
+            var env = new DefaultEnvironment();
+            var executor = new Executor(env);
+            executor.builtins["logd"] = (x) => {
+                _logger.LogDebug(((Lisp.String)x.First()).Value(), x.Skip(1).ToArray());
+                return Lisp_Boolean.TRUE;
+            };
+            executor.builtins["logi"] = (x) => {
+                _logger.LogInformation(((Lisp.String)x.First()).Value(), x.Skip(1).ToArray());
+                return Lisp_Boolean.TRUE;
+            };
+            executor.builtins["logw"] = (x) => {
+                _logger.LogWarning(((Lisp.String)x.First()).Value(), x.Skip(1).ToArray());
+                return Lisp_Boolean.TRUE;
+            };
+            executor.builtins["loge"] = (x) => {
+                _logger.LogError(((Lisp.String)x.First()).Value(), x.Skip(1).ToArray());
+                return Lisp_Boolean.TRUE;
+            };
+            if (Plugin.Instance is not null) {
+                executor.eval(Plugin.Instance.Configuration.InitialProgram);
+            } else {
+                throw new ApplicationException("Plugin Instance is not yet initialized");
+            }
+            return executor;
+        }
+
         private IEnumerable<Guid> FilterPlaylistItems(IEnumerable<BaseItem> items, User user, SmartPlaylistDto smartPlaylist) {
-            List<Guid> results = new List<Guid>();
+            List<BaseItem> results = new List<BaseItem>();
-            Expression expression = new Parser(StringTokenStream.generate(smartPlaylist.Program)).parse();
+            Expression expression = new Parser(StringTokenStream.generate(smartPlaylist.Program)).parse(); // parse here, so that we don't repeat the work for each item
-            Executor executor = new Executor(new DefaultEnvironment());
+            Executor executor = SetupExecutor();
-            executor.environment.Set("user", new Lisp_Object(user));
+
+            executor.environment.Set("*user*", Lisp_Object.FromBase(user));
             foreach (var i in items) {
-                executor.environment.Set("item", new Lisp_Object(i));
+                executor.environment.Set("*item*", Lisp_Object.FromBase(i));
                 var r = executor.eval(expression);
                 _logger.LogTrace("Item {0} evaluated to {1}", i, r.ToString());
-                if ((r is not Lisp_Boolean r_bool) || (r_bool.value)) {
+                if ((r is not Lisp_Boolean r_bool) || (r_bool.Value())) {
                     _logger.LogDebug("Added '{0}' to Smart Playlist {1}", i, smartPlaylist.Name);
-                    results.Add(i.Id);
+                    results.Add(i);
                 }
             }
-            return results;
+            executor = SetupExecutor();
+            executor.environment.Set("*user*", Lisp_Object.FromBase(user));
+            executor.environment.Set("*items*", Lisp_Object.FromBase(results));
+            results = new List<BaseItem>();
+            var sort_result = executor.eval(smartPlaylist.SortProgram);
+            if (sort_result is Cons sorted_items) {
+                foreach (var i in sorted_items.ToList()) {
+                    if (i is Lisp_Object iObject && iObject.Value() is BaseItem iBaseItem) {
+                        results.Add(iBaseItem);
+                        continue;
+                    }
+                    throw new ApplicationException($"Returned sorted list does contain unexpected items, got {i}");
+                }
+            } else if (sort_result == Lisp_Boolean.FALSE) {
+            } else {
+                throw new ApplicationException($"Did not return a list of items, returned {sort_result}");
+            }
+            return results.Select(x => x.Id);
         }
 
         private IEnumerable<BaseItem> GetAllUserMedia(User user) {
@@ -132,7 +166,17 @@ namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
 
         public async Task ExecuteAsync(IProgress<double> progress, CancellationToken cancellationToken) {
             _logger.LogInformation("Started regenerate Smart Playlists");
-            foreach (SmartPlaylistDto dto in await _store.GetAllSmartPlaylistsAsync()) {
+            _logger.LogDebug("Loaded Assemblies:");
+            foreach (var asm in AppDomain.CurrentDomain.GetAssemblies()) {
+                _logger.LogDebug("- {0}", asm);
+            }
+            var i = 0;
+            var all_playlists = await _store.GetAllSmartPlaylistsAsync();
+            foreach (SmartPlaylistDto dto in all_playlists) {
+                if (!dto.Enabled) {
+                    i += 1;
+                    continue;
+                }
                 var changedDto = false;
                 if (dto.Playlists.Length == 0) {
                     dto.Playlists = _userManager.UsersIds.Select(x => new SmartPlaylistLinkDto {
@@ -167,6 +211,8 @@ namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
                     await ClearPlaylist(playlist);
                     await _playlistManager.AddItemToPlaylistAsync(playlist.Id, insertItems, playlistLink.UserId);
                 }
+                i += 1;
+                progress.Report(100 * ((double)i)/all_playlists.Count());
             }
         }
 
@@ -176,7 +222,7 @@ namespace Jellyfin.Plugin.SmartPlaylist.ScheduledTasks {
                 throw new ArgumentException("");
             }
             var existingItems = playlist_new.GetManageableItems().ToList();
-            await _playlistManager.RemoveItemFromPlaylistAsync(playlist.Id.ToString(), existingItems.Select(x => x.Item1.Id));
+            await _playlistManager.RemoveItemFromPlaylistAsync(playlist.Id.ToString(), existingItems.Select(x => x.Item1.ItemId?.ToString("N", CultureInfo.InvariantCulture)));
         }
     }
 }

Jellyfin.Plugin.SmartPlaylist/SmartPlaylistDto.cs

@@ -41,19 +41,22 @@ namespace Jellyfin.Plugin.SmartPlaylist {
 
     [Serializable]
     public class SmartPlaylistDto : ISerializable {
-        private static string DEFAULT_PROGRAM = "(begin (invoke item 'IsFavoriteOrLiked' (user)))";
+        private static string DEFAULT_PROGRAM = "(begin (invoke item \"IsFavoriteOrLiked\" (list *user*)))";
+        private static string DEFAULT_SORT_PROGRAM = "(begin *items*)";
         public SmartPlaylistId Id { get; set; }
         public SmartPlaylistLinkDto[] Playlists { get; set; }
         public string Name { get; set; }
         public string Program { get; set; }
+        public string SortProgram { get; set; }
         public string? Filename { get; set; }
         public bool Enabled { get; set; }
 
         public SmartPlaylistDto() {
-            Id = Guid.NewGuid();
+            Id = "";
             Playlists = [];
             Name = Id.ToString();
             Program = DEFAULT_PROGRAM;
+            SortProgram = DEFAULT_SORT_PROGRAM;
             Filename = null;
             Enabled = true;
         }
@@ -62,7 +65,7 @@ namespace Jellyfin.Plugin.SmartPlaylist {
             if (info.GetValue("Id", typeof(SmartPlaylistId)) is SmartPlaylistId _Id) {
                 Id = _Id;
             } else {
-                Id = Guid.NewGuid();
+                Id = "";
             }
             if (info.GetValue("Playlists", typeof(SmartPlaylistLinkDto[])) is SmartPlaylistLinkDto[] _Playlists) {
                 Playlists = _Playlists;
@@ -79,6 +82,11 @@ namespace Jellyfin.Plugin.SmartPlaylist {
             } else {
                 Program = DEFAULT_PROGRAM;
             }
+            if (info.GetValue("SortProgram", typeof(string)) is string _SortProgram) {
+                SortProgram = _SortProgram;
+            } else {
+                SortProgram = DEFAULT_SORT_PROGRAM;
+            }
             if (info.GetValue("Filename", typeof(string)) is string _Filename) {
                 Filename = _Filename;
             } else {

Jellyfin.Plugin.SmartPlaylist/SmartPlaylistFileSystem.cs

@@ -16,13 +16,21 @@ namespace Jellyfin.Plugin.SmartPlaylist {
         }
         public string StoragePath { get; }
         public string GetSmartPlaylistFilePath(SmartPlaylistId smartPlaylistId) {
-            return Path.Combine(StoragePath, $"{smartPlaylistId}.json");
+            return Path.Combine(StoragePath, $"{smartPlaylistId}.yaml");
         }
         public string FindSmartPlaylistFilePath(SmartPlaylistId smartPlaylistId) {
-            return Directory.GetFiles(StoragePath, $"{smartPlaylistId}.json", SearchOption.AllDirectories).First();
+            return Directory.GetFiles(StoragePath, $"{smartPlaylistId}.yaml", SearchOption.AllDirectories).Concat(
+                Directory.GetFiles(StoragePath, $"{smartPlaylistId}.yml", SearchOption.AllDirectories)
+            ).Concat(
+                Directory.GetFiles(StoragePath, $"{smartPlaylistId}.json", SearchOption.AllDirectories)
+            ).First();
         }
         public string[] FindAllSmartPlaylistFilePaths() {
-            return Directory.GetFiles(StoragePath, "*.json", SearchOption.AllDirectories);
+            return Directory.GetFiles(StoragePath, "*.yaml", SearchOption.AllDirectories).Concat(
+                Directory.GetFiles(StoragePath, "*.yml", SearchOption.AllDirectories)
+            ).Concat(
+                Directory.GetFiles(StoragePath, "*.json", SearchOption.AllDirectories)
+            ).ToArray();
         }
     }
 }

Jellyfin.Plugin.SmartPlaylist/Store.cs

@@ -1,10 +1,11 @@
-using System.Text.Json;
+using YamlDotNet.Serialization;
 
 namespace Jellyfin.Plugin.SmartPlaylist {
     public interface IStore {
         Task<SmartPlaylistDto> GetSmartPlaylistAsync(SmartPlaylistId smartPlaylistId);
         Task<SmartPlaylistDto[]> GetAllSmartPlaylistsAsync();
         Task SaveSmartPlaylistAsync(SmartPlaylistDto smartPlaylist);
+        void DeleteSmartPlaylistById(SmartPlaylistId smartPlaylistId);
         void DeleteSmartPlaylist(SmartPlaylistDto smartPlaylist);
     }
 
@@ -14,12 +15,24 @@ namespace Jellyfin.Plugin.SmartPlaylist {
             _fileSystem = fileSystem;
         }
         private async Task<SmartPlaylistDto> LoadPlaylistAsync(string filename) {
-            await using var r = File.OpenRead(filename);
+            var r = await File.ReadAllTextAsync(filename);
-            var dto = (await JsonSerializer.DeserializeAsync<SmartPlaylistDto>(r).ConfigureAwait(false));
+            if (r.Equals("")) {
-            if (dto == null) {
+                r = "{}";
+            }
+            var dto = new DeserializerBuilder().Build().Deserialize<SmartPlaylistDto>(r);
+            if (dto == null)
+            {
                 throw new ApplicationException("");
             }
+            if (dto.Id != Path.GetFileNameWithoutExtension(filename)) {
+                dto.Id = Path.GetFileNameWithoutExtension(filename);
+            }
+            if (dto.Name != Path.GetFileNameWithoutExtension(filename)) {
+                dto.Name = Path.GetFileNameWithoutExtension(filename);
+            }
+            if (dto.Filename != filename) {
                 dto.Filename = filename;
+            }
             return dto;
         }
         public async Task<SmartPlaylistDto> GetSmartPlaylistAsync(SmartPlaylistId smartPlaylistId) {
@@ -33,10 +46,10 @@ namespace Jellyfin.Plugin.SmartPlaylist {
         }
         public async Task SaveSmartPlaylistAsync(SmartPlaylistDto smartPlaylist) {
             string filename = _fileSystem.GetSmartPlaylistFilePath(smartPlaylist.Id);
-            await using var w = File.Create(filename);
+            var text = new SerializerBuilder().Build().Serialize(smartPlaylist);
-            await JsonSerializer.SerializeAsync(w, smartPlaylist).ConfigureAwait(false);
+            await File.WriteAllTextAsync(filename, text);
         }
-        private void DeleteSmartPlaylistById(SmartPlaylistId smartPlaylistId) {
+        public void DeleteSmartPlaylistById(SmartPlaylistId smartPlaylistId) {
             try {
                 string filename = _fileSystem.FindSmartPlaylistFilePath(smartPlaylistId);
                 if (File.Exists(filename)) { File.Delete(filename); }

Jellyfin.Plugin.SmartPlaylist/Types.cs

@@ -2,4 +2,4 @@ global using System;
 
 global using UserId = System.Guid;
 global using PlaylistId = System.Guid;
-global using SmartPlaylistId = System.Guid;
+global using SmartPlaylistId = string;

Jellyfin.Plugin.SmartPlaylist/build.yaml

@@ -1,7 +1,7 @@
 name: Smart Playlist
 guid: dd2326e3-4d3e-4bfc-80e6-28502c1131df
-version: 0.1.1.0
+version: 0.4.0.0
-targetAbi: 10.10.0.0
+targetAbi: 10.10.3.0
 framework: net8.0
 owner: redxef
 overview: Smart playlists with Lisp filter engine.
@@ -12,5 +12,68 @@ description: |
 category: "General"
 artifacts:
   - jellyfin-smart-playlist.dll
+  - YamlDotNet.dll
 changelog: |
+  ## v0.4.0.0
+  - Add a basic UI to configure the playlists.
+  - It's now possible to print log messages to the jellyfin log by calling `logd`, `logi`, `logw` or `loge`
+    for the respective levels `debug`, `info`, `warning` or `error`.
+  - Allow calling generic methods via `(invoke-generic object methodname args list-of-types)`.
+  - Add quoting via single quote: `'`.
+  - Add special case for `(quote <form>)` to be rendered as `'<form>`.
+  - It is now possible to include comments in the source via a semicolon (`;`).
+  - Respect the `Enabled` flag and only process the playlists that are enabled.
+  - New methods have been added: `rand`, `shuf`.
+  - Add `find-artist`, `get-name` and `find-parent` default definitions.
+  - Update YamlDotNet to v16.2.1.
+
+  **Breaking changes**:
+  - Rename global environment variables to be enclosed by `*`.
+
+  **Fixes**:
+  - The initialization of the executor now contains the same default definitions for the SortProgram and the normal Program.
+  - The progress report now considers the SmartPlaylists and not the individual playlists per user.
+  - It is now possible to pass builtins as arguments. Previously to get `(qsort > (list 1 2 3))` one had to write
+    something like this: `(qsort (lambda (a b) (> a b)) (list 1 2 3))`.
+  - A program no longer has to be a list, `t` is a valid program.
+  - Fix list parsing in cases where a space was before the closing parenthesis.
+
+
+  ## v0.3.0.0
+  - Add a second program (`SortProgram`) which is run after the filtering, this
+    program should return the list of items, but in the order in which they should appear in
+    the playlist. The default is `(begin items)` which returns the list as is.
+  - Extend builtin lisp definitions: add `qsort` and string comparison methods
+  - Extend default program definitions: add `all-genres` and `any-genres` to quickly specify a list of genres which to include (or excluding when negating)
+  - Update Jellyfin to v 10.10.3
+
+  **Fixes**:
+  - The progress report now correctly gives a percentage in the range [0, 100].
+
+  ## v0.2.2.0
+  - Update Jellyfin to v 10.10.2
+
+  ## v0.2.1.0
+  - Make default program configuration a textarea in the settings page
+  - Add convinience definitions: `is-type`, `name-contains`
+  - Update YamlDotNet to v 16.2.0
+
+  **Fixes**:
+  - The default program was malformed, a closing bracket was at the wrong position
+  - The `haskeys` function could only be called on Objects
+
+  ## v0.2.0.0
+  - Switch to yaml loading, old json files are still accepted
+  - Rework lisp interpreter to be more conventional
+  - Use arbitrary strings as ids for playlists
+  - Add configuration page with some default definitions for
+    the filter expressions.
+
+  **Breaking Changes**:
+  - The lisp interpreter will now only detect strings in double quotes (`"`).
+  - The interpreter will also not allow specifying lists without quoting them.
+    `(1 2 3)` ... used to work but will no longer, replace by either specifying
+    the list as `(list 1 2 3)` or `(quote (1 2 3))`.
+
+  ## v0.1.1.0
   - Initial Alpha release.

Jellyfin.Plugin.SmartPlaylist/configPage.html

@@ -2,35 +2,47 @@
 <html lang="en">
 <head>
     <meta charset="utf-8">
-    <title>Template</title>
+    <title>SmartPlaylist</title>
 </head>
 <body>
-    <div id="TemplateConfigPage" data-role="page" class="page type-interior pluginConfigurationPage" data-require="emby-input,emby-button,emby-select,emby-checkbox">
+    <div id="SmartPlaylistConfigPage" data-role="page" class="page type-interior pluginConfigurationPage" data-require="emby-input,emby-button,emby-select,emby-checkbox">
         <div data-role="content">
             <div class="content-primary">
-                <form id="TemplateConfigForm">
+                <form id="SmartPlaylistConfigForm">
-                    <div class="selectContainer">
+                    <div class="inputContainer">
-                        <label class="selectLabel" for="Options">Several Options</label>
+                        <label class="inputLabel inputLabelUnfocused" for="InitialProgram">Initial Program</label>
-                        <select is="emby-select" id="Options" name="Options" class="emby-select-withcolor emby-select">
+                        <div class="fieldDescription">A program which can set up the environment</div>
-                            <option id="optOneOption" value="OneOption">One Option</option>
+                        <textarea id="InitialProgram" class="emby-input smartplaylist-monospace" name="InitialProgram" rows="16" cols="120"></textarea>
-                            <option id="optAnotherOption" value="AnotherOption">Another Option</option>
+                    </div>
+                    <div>
+                        <label class="inputLabel inputLabelUnfocused" for="SmartplaylistSelection">Choose a playlist to edit</label>
+                        <select id="SmartplaylistSelection" class="emby-select">
+                        </select>
+                    </div>
+                    <div>
+                        <label class="inputLabel inputLabelUnfocused" for="SmartplaylistEditName">Name</label>
+                        <input id="SmartplaylistEditName" type="text" class="emby-input"/>
+                    </div>
+                    <div class="inputContainer">
+                        <label class="inputLabel inputLabelUnfocused" for="SmartplaylistEditProgram">Program</label>
+                        <div class="fieldDescription">A program which should return <code>t</code> or <code>nil</code> to include or exclude the provided <code>item</code>.</div>
+                        <textarea id="SmartplaylistEditProgram" class="emby-input smartplaylist-monospace" name="Program" rows="16" cols="120"></textarea>
+                    </div>
+                    <div class="inputContainer">
+                        <label class="inputLabel inputLabelUnfocused" for="SmartplaylistEditSortProgram">Sort Program</label>
+                        <div class="fieldDescription">A program which should return a list of items to include in the playlist, sorted however you like.</div>
+                        <textarea id="SmartplaylistEditSortProgram" class="emby-input smartplaylist-monospace" name="SortProgram" rows="16" cols="120"></textarea>
+                    </div>
+                    <div class="inputContainer">
+                        <label class="inputLabel inputLabelUnfocused" for="SmartplaylistEditUsers">Users</label>
+                        <div class="fieldDescription">Which users should get access to the playlist.</div>
+                        <select multiple id="SmartplaylistEditUsers" class="emby-select">
                         </select>
                     </div>
                     <div class="inputContainer">
-                        <label class="inputLabel inputLabelUnfocused" for="AnInteger">An Integer</label>
+                        <label class="inputLabel inputLabelUnfocused" for="SmartPlaylistEditEnabled">Enabled</label>
-                        <input id="AnInteger" name="AnInteger" type="number" is="emby-input" min="0" />
+                        <div class="fieldDescription">Is the playlist enabled.</div>
-                        <div class="fieldDescription">A Description</div>
+                        <input id="SmartplaylistEditEnabled" type="checkbox" class="emby-input"/>
-                    </div>
-                    <div class="checkboxContainer checkboxContainer-withDescription">
-                        <label class="emby-checkbox-label">
-                            <input id="TrueFalseSetting" name="TrueFalseCheckBox" type="checkbox" is="emby-checkbox" />
-                            <span>A Checkbox</span>
-                        </label>
-                    </div>
-                    <div class="inputContainer">
-                        <label class="inputLabel inputLabelUnfocused" for="AString">A String</label>
-                        <input id="AString" name="AString" type="text" is="emby-input" />
-                        <div class="fieldDescription">Another Description</div>
                     </div>
                     <div>
                         <button is="emby-button" type="submit" class="raised button-submit block emby-button">
@@ -40,36 +52,146 @@
                 </form>
             </div>
         </div>
+        <style>
+            .smartplaylist-monospace {
+                font-family: monospace;
+            }
+        </style>
         <script type="text/javascript">
-            var TemplateConfig = {
+            var SmartPlaylistConfig = {
                 pluginUniqueId: 'dd2326e3-4d3e-4bfc-80e6-28502c1131df'
             };
 
-            document.querySelector('#TemplateConfigPage')
+            function changeEditBox(config, id) {
+                const selection = document.querySelector('#SmartplaylistSelection');
+                const editName = document.querySelector('#SmartplaylistEditName');
+                const editProgram = document.querySelector('#SmartplaylistEditProgram');
+                const editSortProgram = document.querySelector('#SmartplaylistEditSortProgram');
+                const editUsers = document.querySelector('#SmartplaylistEditUsers');
+                const editEnabled = document.querySelector('#SmartplaylistEditEnabled');
+                if (id === null) {
+                    selection.selectedIndex = 0;
+                    editName.value = 'My New Smartplaylist';
+                    editProgram.value = '(is-favourite)';
+                    editSortProgram.value = '(begin *items*)';
+                    editUsers.innerHTML = '';
+                    for (const u of config.Users) {
+                        var o = document.createElement('option');
+                        o.value = u[0];
+                        o.innerHTML = u[1];
+                        o.setAttribute('selected', 'selected');
+                        editUsers.appendChild(o);
+                    }
+                    editEnabled.checked = true;
+                    return;
+                }
+                function matchId(p) {
+                    return p.Id == id;
+                }
+                const index = config.Playlists.map(function (x) { return x.Id }).indexOf(id);
+                selection.selectedIndex = index + 1;
+                const p = config.Playlists[index];
+                editName.value = p.Name;
+                editProgram.value = p.Program;
+                editSortProgram.value = p.SortProgram;
+                editUsers.innerHTML = '';
+                for (const u of config.Users) {
+                    var o = document.createElement('option');
+                    o.value = u[0];
+                    o.innerHTML = u[1];
+                    if (p.Playlists.map((x) => x.UserId).includes(u[0])) {
+                        o.setAttribute('selected', 'selected');
+                    }
+                    editUsers.appendChild(o);
+                }
+                editEnabled.checked = p.Enabled;
+            }
+
+            function fillPlaylistSelect(config) {
+                const selection = document.querySelector('#SmartplaylistSelection');
+                selection.innerHTML = '';
+                var o = document.createElement('option');
+                o.value = null;
+                o.innerHTML = 'Create new playlist ...';
+                selection.appendChild(o);
+                for (const i of config.Playlists) {
+                    var o = document.createElement('option');
+                    o.value = i.Id;
+                    o.innerHTML = i.Name;
+                    selection.appendChild(o);
+                }
+            }
+
+            document.querySelector('#SmartPlaylistConfigPage')
                 .addEventListener('pageshow', function() {
                     Dashboard.showLoadingMsg();
-                    ApiClient.getPluginConfiguration(TemplateConfig.pluginUniqueId).then(function (config) {
+                    ApiClient.getPluginConfiguration(SmartPlaylistConfig.pluginUniqueId).then(function (config) {
-                        document.querySelector('#Options').value = config.Options;
+                        document.querySelector('#InitialProgram').value = config.InitialProgram;
-                        document.querySelector('#AnInteger').value = config.AnInteger;
+                        fillPlaylistSelect(config);
-                        document.querySelector('#TrueFalseSetting').checked = config.TrueFalseSetting;
+                        changeEditBox(config, (config.Playlists.length > 0) ? config.Playlists[0].Id : null);
-                        document.querySelector('#AString').value = config.AString;
                         Dashboard.hideLoadingMsg();
                     });
                 });
 
-            document.querySelector('#TemplateConfigForm')
+            document.querySelector('#SmartplaylistSelection')
+                .addEventListener('change', function() {
+                    Dashboard.showLoadingMsg();
+                    ApiClient.getPluginConfiguration(SmartPlaylistConfig.pluginUniqueId).then(function (config) {
+                        const selection = document.querySelector('#SmartplaylistSelection');
+                        changeEditBox(config, (selection.selectedIndex > 0) ? config.Playlists[selection.selectedIndex - 1].Id : null);
+                        Dashboard.hideLoadingMsg();
+                    });
+                });
+
+            document.querySelector('#SmartPlaylistConfigForm')
                 .addEventListener('submit', function(e) {
                 Dashboard.showLoadingMsg();
-                ApiClient.getPluginConfiguration(TemplateConfig.pluginUniqueId).then(function (config) {
+                ApiClient.getPluginConfiguration(SmartPlaylistConfig.pluginUniqueId).then(function (config) {
-                    config.Options = document.querySelector('#Options').value;
+                    config.InitialProgram = document.querySelector('#InitialProgram').value;
-                    config.AnInteger = document.querySelector('#AnInteger').value;
+                    const selection = document.querySelector('#SmartplaylistSelection');
-                    config.TrueFalseSetting = document.querySelector('#TrueFalseSetting').checked;
+                    const editName = document.querySelector('#SmartplaylistEditName');
-                    config.AString = document.querySelector('#AString').value;
+                    const editProgram = document.querySelector('#SmartplaylistEditProgram');
-                    ApiClient.updatePluginConfiguration(TemplateConfig.pluginUniqueId, config).then(function (result) {
+                    const editSortProgram = document.querySelector('#SmartplaylistEditSortProgram');
+                    const editUsers = document.querySelector('#SmartplaylistEditUsers');
+                    const editEnabled = document.querySelector('#SmartplaylistEditEnabled');
+                    var index = selection.selectedIndex;
+                    if (index === 0) {
+                        const o = {
+                            Id: editName.value,
+                            Name: editName.value,
+                            Program: editProgram.value,
+                            SortProgram: editSortProgram.value,
+                            Playlists: Array.from(editUsers.options).filter((x) => x.selected).map((x) => {
+                                const m = {UserId: x.value, PlaylistId: "00000000-0000-0000-0000-000000000000"};
+                                return m;
+                            }),
+                            Enabled: editEnabled.checked,
+                        };
+                        config.Playlists.push(o);
+                    } else {
+                        config.Playlists[index-1].Id = editName.value;
+                        config.Playlists[index-1].Name = editName.value;
+                        config.Playlists[index-1].Program = editProgram.value;
+                        config.Playlists[index-1].SortProgram = editSortProgram.value;
+                        config.Playlists[index-1].Playlists = Array.from(editUsers.options).filter((x) => x.selected).map((x) => {
+                            const existing = config.Playlists[index-1].Playlists.filter((x_) => x_.UserId === x.value).map((x_) => x_.PlaylistId);
+                            const m = {UserId: x.value, PlaylistId: ((existing.length > 0) ? existing[0] : "00000000-0000-0000-0000-000000000000")};
+                            return m;
+                        }),
+                        config.Playlists[index-1].Enabled = editEnabled.checked;
+                    }
+                    ApiClient.updatePluginConfiguration(SmartPlaylistConfig.pluginUniqueId, config).then(function (result) {
                         Dashboard.processPluginConfigurationUpdateResult(result);
+                            ApiClient.getPluginConfiguration(SmartPlaylistConfig.pluginUniqueId).then(function (config) {
+                            document.querySelector('#InitialProgram').value = config.InitialProgram;
+                            fillPlaylistSelect(config);
+                            changeEditBox(config, (config.Playlists.length > 0) ? config.Playlists[0].Id : null);
+                            Dashboard.hideLoadingMsg();
                         });
                     });
 
+                });
+
                 e.preventDefault();
                 return false;
             });

Jellyfin.Plugin.SmartPlaylist/jellyfin-smart-playlist.csproj

@@ -2,15 +2,21 @@
 
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
-    <RootNamespace>jellyfin_smart_playlist</RootNamespace>
+    <RootNamespace>Jellyfin.Plugin.SmartPlaylist</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
-    <Version>0.1.1.0</Version>
+    <Version>0.4.0.0</Version>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Jellyfin.Controller" Version="10.10.0" />
+    <PackageReference Include="Jellyfin.Controller" Version="10.10.3" />
-    <PackageReference Include="Jellyfin.Model" Version="10.10.0" />
+    <PackageReference Include="Jellyfin.Model" Version="10.10.3" />
+    <PackageReference Include="YamlDotNet" Version="16.2.1" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Remove="configPage.html"/>
+    <EmbeddedResource Include="configPage.html"/>
   </ItemGroup>
 
 </Project>

README.md

@@ -2,78 +2,67 @@
 
 Smart playlists with Lisp filter engine.
 
+This readme contains instructions for the most recent changes in
+the development branch (`main`). To view the file appropriate
+for your version select the tag corresponding to your version.
+The latest version is [v0.4.0.0](https://gitea.redxef.at/redxef/jellyfin-smart-playlist/src/tag/v0.4.0.0).
+
 ## How to use
 
 After [installing](#installation) the plugin and restarting Jellyfin
-create a file in `config/data/smartplaylists` like this:
+go to the plugin settings and below the `Initial Program` configuration
+choose the smart playlist you want to edit, or `Create new playlist ...`
+to create a new one.
 
-```
+[Go here](examples.md) to see some example configurations.
-$ echo '{}' > config/data/smartplaylists/a.json
-```
 
-Afterwards run the Task `(re)generate Smart Playlists`, this will rename
+Below are all the configuration values for a smart playlist.
-the `json` file and populate it with some default values. You can now
-adjust the file to your liking. [Go here](examples/index.md) to see more
-examples.
-
-Example file
-```json
-{
-  "Id": "a1d02dee-f1da-4472-bee3-f568c15c8360",
-  "Playlists": [
-    {
-      "PlaylistId": "24f12e1e-3278-d6d6-0ca4-066e93296c95",
-      "UserId": "6eec632a-ff0d-4d09-aad0-bf9e90b14bc6"
-    }
-  ],
-  "Name": "a1d02dee-f1da-4472-bee3-f568c15c8360",
-  "Program": "(begin (invoke item 'IsFavoriteOrLiked' (user)))",
-  "Filename": "/config/data/smartplaylists/a1d02dee-f1da-4472-bee3-f568c15c8360.json",
-  "Enabled": true
-}
-```
-
-### Id
-
-Arbitrary Id assigned to this playlist, can usually be left alone.
-The filename is derived from this.
-
-### Playlists
-
-A list of Playlist/User mappings. By default all users get an entry.
-
-The ids must have the dashes in them as of now. To convert a id
-from without dashes to the canonical form run this command:
-
-`echo '<your id here>' | python3 -c 'import uuid; import sys; print(uuid.UUID(sys.stdin.read().strip()))'`
-
-To get your user id navigate to your user profile and copy the part
-after `userId` in the address bar.
-
-#### PlaylistId
-
-The id of the playlist that should be managed, must be owned by the
-corresponding user.
-
-#### UserId
-
-The user associated with this playlist.
 
 ### Name
 
 The name of the generated playlists, this is just a default value.
 If the user changes the name of their playlist the plugin will
-work as usual
+still work and remember the correct playlist.
 
 ### Program
 
 A lisp program to decide on a per item basis if it should be included in
-the playlist, return `nil` to not include items, return `t` to include
+the playlist, return `nil` to not include items, return any other value
-them.
+to include them. Global variables `*user*` and `*item*` are predefined
+and contain a [User](https://github.com/jellyfin/jellyfin/blob/master/Jellyfin.Data/Entities/User.cs) and
+[BaseItem](https://github.com/jellyfin/jellyfin/blob/master/MediaBrowser.Controller/Entities/BaseItem.cs)
+respectively.
 
-### Filename
+**!!! The filter expression will include all items matching, if you do
+not specify the kind of item to include/exclude all of them will be
+added. Should you allow a playlist to be included all of it's items
+will be added to the generated playlist !!!**
 
-The path to this file.
+It's best to be explicit and always specify the item kinds you want to
+include: `(and (or (is-type "MusicAlbum") (is-type "Audio")) . rest of filter)`.
+
+The configuration page defines some useful functions to make it easier
+to create filters. The above filter for liked items could be simplified
+to: `(is-favourite)`.
+
+*Go [here](lisp.md) to get an overview of the built-in functions.*
+
+### SortProgram
+
+This works exactly like [Program](#program), but the input is the
+user and a list of items (`*items*`) matched by [Program](#program).
+The default is `(begin *items*)`, which doesn't sort at all. To sort
+the items by name you could use the following program:
+
+```lisp
+(qsort
+  (lambda
+    (a b)
+    (string>
+      (car (getitems a "Name"))
+      (car (getitems b "Name"))))
+  *items*)
+```
 
 ### Enabled
 
@@ -89,3 +78,17 @@ to Jellyfin:
 Go to `Dashboard>Catalog>(Gear)>(Plus)` and paste the provided link into
 the field labeled `Repository URL`, give the plugin a descriptive name
 too.
+
+## Releasing a new version
+
+1. Write the changelog: `git log --oneline $prev_version..`
+2. Update the following files to include up-to-date version numbers
+   and changelogs, if applicable:
+   - `README.md`
+   - `Jellyfin.Plugin.SmartPlaylist/build.yaml`
+   - `Jellyfin.Plugin.SmartPlaylist/jellyfin-smart-playlist.csproj`
+   Don't forget to also bump the ABI version of Jellyfin.
+3. Push the changes
+4. Create a new release with the changelog, mark as pre-release if
+   applicable.
+5. Done! The build pipeline will do the rest.

Tests/Tests.cs

@@ -1,7 +1,6 @@
-using Xunit;
+using Lisp_Boolean = Jellyfin.Plugin.SmartPlaylist.Lisp.Boolean;
-using Lisp_Environment = Jellyfin.Plugin.SmartPlaylist.Lisp.Environment;
+using Lisp_Object = Jellyfin.Plugin.SmartPlaylist.Lisp.Object;
-using Lisp_Boolean = Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler.Boolean;
+using Lisp_Integer = Jellyfin.Plugin.SmartPlaylist.Lisp.Integer;
-using Lisp_Object = Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler.Object;
 using Jellyfin.Plugin.SmartPlaylist.Lisp;
 using Jellyfin.Plugin.SmartPlaylist.Lisp.Compiler;
 
@@ -16,45 +15,45 @@ namespace Tests
         }
         public int i { get => _i; }
         public bool b { get => _b; }
+        public int I() {
+            return _i;
+        }
+        public string G<E>() {
+            return typeof(E).FullName;
+        }
     }
 
     public class Test {
         [Fact]
         public static void TestTokenizer() {
             StringTokenStream sts = StringTokenStream.generate("(\"some literal string\" def ghj +100 -+300 1 >= ++ !=)");
-            Assert.Equal(sts.Get().value, "(");
+            Assert.Equal("(", sts.Get().value);
-            Assert.Equal(sts.Get().value, "\"");
+            Assert.Equal("\"", sts.Get().value);
-            Assert.Equal(sts.Get().value, "some");
+            Assert.Equal("some", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "literal");
+            Assert.Equal("literal", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "string");
+            Assert.Equal("string", sts.Get().value);
-            Assert.Equal(sts.Get().value, "\"");
+            Assert.Equal("\"", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "def");
+            Assert.Equal("def", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "ghj");
+            Assert.Equal("ghj", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "+");
+            Assert.Equal("+100", sts.Get().value);
-            Assert.Equal(sts.Get().value, "100");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal("-+300", sts.Get().value);
-            Assert.Equal(sts.Get().value, "-");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "+");
+            Assert.Equal("1", sts.Get().value);
-            Assert.Equal(sts.Get().value, "300");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(">=", sts.Get().value);
-            Assert.Equal(sts.Get().value, "1");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal("++", sts.Get().value);
-            Assert.Equal(sts.Get().value, ">");
+            Assert.Equal(" ", sts.Get().value);
-            Assert.Equal(sts.Get().value, "=");
+            Assert.Equal("!=", sts.Get().value);
-            Assert.Equal(sts.Get().value, " ");
+            Assert.Equal(")", sts.Get().value);
-            Assert.Equal(sts.Get().value, "+");
-            Assert.Equal(sts.Get().value, "+");
-            Assert.Equal(sts.Get().value, " ");
-            Assert.Equal(sts.Get().value, "!");
-            Assert.Equal(sts.Get().value, "=");
-            Assert.Equal(sts.Get().value, ")");
             sts.Commit();
-            Assert.Equal(sts.Available(), 0);
+            Assert.Equal(0, sts.Available());
         }
 
         [Fact]
@@ -69,115 +68,205 @@ namespace Tests
             p = new Parser(sts);
             Assert.Equal(program, string.Format("{0}", p.parse()));
 
-            //program = "(* 2.4 2)";
+            program = "(abc '(1 2 3))";
-            //sts = StringTokenStream.generate(program);
+            sts = StringTokenStream.generate(program);
-            //p = new Parser(sts);
+            p = new Parser(sts);
-            //Assert.Equal(program, p.parse().ToString());
+            Assert.Equal(program, string.Format("{0}", p.parse()));
+
+            program = "(abc \"'(1 2 3)\")";
+            sts = StringTokenStream.generate(program);
+            p = new Parser(sts);
+            Assert.Equal(program, string.Format("{0}", p.parse()));
+
+            program = """
+                (begin ;this too
+                  ;;; this is a comment
+                  t
+                  )
+            """;
+            sts = StringTokenStream.generate(program);
+            p = new Parser(sts);
+            Assert.Equal("(begin t)", string.Format("{0}", p.parse()));
         }
 
         [Fact]
         public static void TestFunctions() {
-            IList<Tuple<string, Expression>> cases = new List<Tuple<string, Expression>>();
+            Executor e = new Executor();
-            Expression e = new Executor().eval("(+ 10 20)");
+            Assert.Equal("(1 2 3)", e.eval("(quote (1 2 3))").ToString());
-            Assert.Equal(((Integer) e).value, 30);
+            Assert.Equal("abc", e.eval("(quote abc)").ToString());
 
-            e = new Executor().eval("(> 1 2)");
+            Assert.Equal("t", e.eval("(atom 1)").ToString());
-            Assert.Equal(((Lisp_Boolean) e).value, false);
+            Assert.Equal("nil", e.eval("(atom (quote (1 2 3)))").ToString());
 
-            e = new Executor().eval("(if (> 1 2) 3 4)");
+            Assert.Equal("t", e.eval("(eq 2 2)").ToString());
-            Assert.Equal(((Integer) e).value, 4);
+            Assert.Equal("nil", e.eval("(eq 2 3)").ToString());
 
-            e = new Executor().eval("(begin (define x 1) x)");
+            Assert.Equal("1", e.eval("(car (quote (1 2 3)))").ToString());
-            Assert.Equal(((Integer) e).value, 1);
+            Assert.Equal("(2 3)", e.eval("(cdr (quote (1 2 3)))").ToString());
 
-            e = new Executor().eval("(apply + (1 2))");
+            Assert.Equal("(1 . 2)", e.eval("(cons 1 2)").ToString());
-            Assert.Equal(((Integer) e).value, 3);
+            Assert.Equal("(1 2)", e.eval("(cons 1 (cons 2 nil))").ToString());
+            Assert.Equal("(1)", e.eval("(cons 1 nil)").ToString());
+            Assert.Equal("(1)", e.eval("(cons 1 ())").ToString());
 
-            e = new Executor().eval("(car (10 20 30))");
+            Assert.Equal("\"Case 2\"", e.eval("""
-            Assert.Equal(((Integer) e).value, 10);
+                (cond
+                    ((eq 1 2) "Case 1")
+                    ((eq 2 2) "Case 2"))
+            """).ToString());
+            Assert.Equal("\"Case 1\"", e.eval("""
+                (cond
+                    ((eq 2 2) "Case 1")
+                    ((eq 2 2) "Case 2"))
+            """).ToString());
+            Assert.Equal("nil", e.eval("""
+                (cond
+                    ((eq 1 2) "Case 1")
+                    ((eq 3 2) "Case 2"))
+            """).ToString());
 
-            e = new Executor().eval("(cdr (10 20 30))");
+            Assert.Equal("t", e.eval("((lambda (a) (eq a a)) 2)").ToString());
-            Assert.Equal(string.Format("{0}", e), "(20 30)");
 
-            e = new Executor().eval("(cons 1 3)");
+            Assert.Equal("t", e.eval("(begin (car (quote (nil 1))) t)").ToString());
-            Assert.Equal(string.Format("{0}", e), "(1 3)");
+            Assert.Equal("(1)", e.eval("(begin t (cdr (quote (nil 1))))").ToString());
 
-            e = new Executor().eval("(cons 1 (2 3))");
+            Assert.Equal("t", e.eval("""
-            Assert.Equal(string.Format("{0}", e), "(1 2 3)");
+                (begin
+                    (define abc 10)
+                    (eq abc abc))
+            """).ToString());
 
-            e = new Executor().eval("(length (cons 1 (2 3)))");
+            Assert.Equal("1", e.eval("""
-            Assert.Equal(string.Format("{0}", e), "3");
+                (begin
+                    (define if (lambda (condition a b) (
+                        cond (condition a) (t b))))
+                    (if (> 2 1) (car (quote (1 2 3))) (cdr (quote (2 3 4)))))
+            """).ToString());
+            Assert.Equal("(3 4)", e.eval("""
+                (begin
+                    (define if (lambda (condition a b) (
+                        cond (condition a) (t b))))
+                    (if (> 0 1) (car (quote (1 2 3))) (cdr (quote (2 3 4)))))
+            """).ToString());
 
-            e = new Executor().eval("(>= 2 2)");
+            Assert.Equal("a", e.eval("'a").ToString());
-            Assert.Equal(string.Format("{0}", e), "t");
+        }
 
-            e = new Executor().eval("(> 2 2))");
+        [Fact]
-            Assert.Equal(string.Format("{0}", e), "nil");
+        public static void TestFunctionsAdvanced() {
+            Executor e = new Executor();
+            Assert.Equal("2", e.eval("""
+                ((lambda (b) b) (car (quote (2 3))))
+            """).ToString());
 
-            e = new Executor().eval("(and 2 3 4)");
+            Assert.Equal("(3 4 5)", e.eval("""
-            Assert.Equal("4", e.ToString());
+                ((lambda (x y . z) z) 1 2 3 4 5)
+            """).ToString());
 
-            e = new Executor().eval("(and 2 nil 4)");
+            Assert.Equal("3", e.eval("""
-            Assert.Equal("nil", e.ToString());
+                (begin
+                    (define if (lambda (condition a b) (cond (condition a) (t b))))
+                    (if (< 1 2) 3 2))
+            """).ToString());
 
-            e = new Executor().eval("(or 2 nil 4)");
+            Assert.Equal("2", e.eval("""
-            Assert.Equal("2", e.ToString());
+                (begin
-
+                    (define if (lambda (condition a b) (cond (condition a) (t b))))
-            e = new Executor().eval("(or nil 4)");
+                    (if (> 1 2) 3 2))
-            Assert.Equal("4", e.ToString());
+            """).ToString());
-
+            Assert.Equal("1", e.eval("""
-            e = new Executor().eval("(= (1 2) (1 2))");
+                (begin
-            Assert.Equal(e.ToString(), "t");
+                    (define if (lambda* (condition a b) (
-
+                        cond ((eval condition) (eval a)) (t (eval b)))))
-            e = new Executor().eval("(= (1 2 3) (1 2))");
+                    (if (> 2 1) (car (quote (1 2 3))) (cdr (quote (2 3 4)))))
-            Assert.Equal(e.ToString(), "nil");
+            """).ToString());
+            Assert.Equal("(3 4)", e.eval("""
+                (begin
+                    (define if (lambda* (condition a b) (
+                        cond ((eval condition) (eval a)) (t (eval b)))))
+                    (if (> 0 1) (car (quote (1 2 3))) (cdr (quote (2 3 4)))))
+            """).ToString());
+            Assert.Equal("120", e.eval("""
+                (begin
+                    (define f (lambda (n) (cond ((<= n 1) 1) (t (* n (f (- n 1)))))))
+                    (f 5))
+            """).ToString());
+            Assert.Equal("120", e.eval("""
+                (begin
+                    (define if (lambda* (condition a b) (
+                        cond ((eval condition) (eval a)) (t (eval b)))))
+                    (define f (lambda (n) (if (<= n 1) 1 (* n (f (- n 1))))))
+                    (f 5))
+            """).ToString());
+            Assert.Equal("(1 2 3 4 5)", e.eval("""
+                (begin
+                    (define if (lambda* (condition a b) (
+                        cond ((eval condition) (eval a)) (t (eval b)))))
+                    ((lambda (. args) args) 1 2 3 4 5))
+            """).ToString());
+            Assert.Equal("t", e.eval("""
+                (begin
+                    (define null (lambda* (x) (
+                        cond ((eval x) nil) (t t))))
+                    (null nil))
+            """).ToString());
+            Assert.Equal("nil", e.eval("""
+                (begin
+                    (define null (lambda* (x) (cond ((eval x) nil) (t t))))
+                    (null (quote (1 2))))
+            """).ToString());
         }
         [Fact]
         public static void ObjectTest() {
             Executor e = new Executor();
             Expression r;
-            e.environment.Set("o", new Lisp_Object(new O(5, false)));
+            e.environment.Set("o", Lisp_Object.FromBase(new O(5, false)));
-            r = e.eval("(haskeys o 'i' 'b')");
+            r = e.eval("""(haskeys o "i" "b")""");
-            Assert.Equal(((Lisp_Boolean)r).value, true);
+            Assert.True(((Lisp_Boolean)r).Value());
-            r = e.eval("(getitems o 'i' 'b')");
+            r = e.eval("""(getitems o "i" "b")""");
-            Assert.Equal(string.Format("{0}", r), "(5 nil)");
+            Assert.Equal("(5 nil)", string.Format("{0}", r));
+            r = e.eval("""(invoke o "I" nil)""");
+            Assert.Equal("5", string.Format("{0}", r));
+            r = e.eval("""(invoke-generic o "G" nil ((lambda (. args) args) "System.String"))""");
+            Assert.Equal("\"System.String\"", string.Format("{0}", r));
         }
 
         [Fact]
-        public static void ScalarTest() {
+        public static void GlobalVariableTest() {
             Executor e = new Executor();
-            Expression r;
+            e.environment.Set("*o*", new Lisp_Integer(5));
-
+            Assert.Equal("10", e.eval("(* *o* 2)").ToString());
-            r = e.eval("(* 2  2)");
-            Assert.Equal("4", r.ToString());
-        }
-
-        [Fact]
-        public static void ProcedureTest() {
-            Executor e = new Executor();
-            Expression r;
-            r = e.eval("((lambda (a) (* a a)) 2)");
-            Assert.Equal(string.Format("{0}", r), "4");
-
-            r = e.eval("(begin (define mull (lambda (a) (* a a))) (mull 3))");
-            Assert.Equal(string.Format("{0}", r), "9");
-
-            r = e.eval("(begin (define fact (lambda (n) (if (<= n 1) 1 (* n (fact (- n 1)))))) (fact 10))");
-            Assert.Equal(string.Format("{0}", r), "3628800");
-
-            r = e.eval("(begin (define find (lambda (item list) (if (= list ()) nil (if (= item (car list)) (car list) (find item (cdr list)))))) (find 3 (1 2 3 4)))");
-            Assert.Equal(string.Format("{0}", r), "3");
-
-            e = new Executor();
-            r = e.eval("(begin (define find (lambda (item list) (if (= list ()) nil (if (= item (car list)) (car list) (find item (cdr list)))))) (find 0 (1 2 3 4)))");
-            Assert.Equal(string.Format("{0}", r), "nil");
         }
 
         [Fact]
         public static void DefaultEnvironmentTest() {
             Executor e = new Executor(new DefaultEnvironment());
-            Assert.Equal("nil", e.eval("(find 0 (1 2 3 4))").ToString());
+            Assert.Equal("1", e.eval("(if nil 0 1)").ToString());
-            Assert.Equal("3", e.eval("(find 3 (1 2 3 4))").ToString());
+            Assert.Equal("0", e.eval("(if t 0 1)").ToString());
+            Assert.Equal("5", e.eval("(if t (if t 5 nil) nil)").ToString());
+            Assert.Equal("nil", e.eval("(if t (if nil 5 nil) nil)").ToString());
+            Assert.Equal("(1 2 3)", e.eval("(list 1 2 3)").ToString());
+            Assert.Equal("3", e.eval("(find 3 (list 1 2 3 4))").ToString());
+            Assert.Equal("nil", e.eval("(find 0 (list 1 2 3 4))").ToString());
+            Assert.Equal("(2 4 6)", e.eval("(map (lambda (x) (* x 2)) (quote (1 2 3)))").ToString());
+            Assert.Equal("nil", e.eval("(and 1 2 3 nil)").ToString());
+            Assert.Equal("t", e.eval("(and t t t t)").ToString());
+            Assert.Equal("t", e.eval("(or nil nil t nil)").ToString());
+            Assert.Equal("nil", e.eval("(or nil nil nil nil)").ToString());
+            Assert.Equal("t", e.eval("(any (lambda (x) (= x 2)) (list 1 2 3 4 5 6))").ToString());
+            Assert.Equal("nil", e.eval("(any (lambda (x) (= x 2)) (list 1 3 4 5 6))").ToString());
+            Assert.Equal("nil", e.eval("(any (lambda (x) (= x 2)) nil)").ToString());
+            Assert.Equal("t", e.eval("(all (lambda (x) (= 1 (% x 2))) (list 1 3 5))").ToString());
+            Assert.Equal("nil", e.eval("(all (lambda (x) (= 1 (% x 2))) (list 1 3 4 5))").ToString());
+            Assert.Equal("nil", e.eval("(all (lambda (x) (= x 2)) nil)").ToString());
+            Assert.Equal("10", e.eval("(fold (lambda (a b) (+ a b)) 0 (list 1 2 3 4))").ToString());
+            Assert.Equal("(2 3 4 5 6 7)", e.eval("(append (list 2 3 4) (list 5 6 7))").ToString());
+            Assert.Equal("(1 2 3 4 5 6 7)", e.eval("(qsort (lambda (a b) (> a b)) (list 5 4 7 3 2 6 1))").ToString());
+
+            //Assert.Equal("", e.eval("(rand)").ToString());
+            //Assert.Equal("", e.eval("(shuf (list 0 1 2 3 4 5 6))").ToString());
+            Assert.Equal("(1 2 3 4 5 6 7)", e.eval("(qsort (lambda (a b) (> a b)) '(5 4 7 3 2 6 1))").ToString());
+            Assert.Equal("(1 2 3 4 5 6 7)", e.eval("(qsort > (list 5 4 7 3 2 6 1))").ToString());
         }
     }
 }

ci/pipeline.yml

@@ -10,20 +10,20 @@ resources:
 - name: source
   type: git
   source:
-    uri: https://gitea.redxef.at/redxef/jellyfin-smart-playlist
+    uri: https://git.redxef.at/redxef/jellyfin-smart-playlist
     branch: main
     fetch_tags: true
     tag_regex: 'v.*'
 - name: manifest
   type: git
   source:
-    uri: ssh://git@gitea.redxef.at:8022/redxef/jellyfin-smart-playlist.git
+    uri: ssh://git@git.redxef.at:8022/redxef/jellyfin-smart-playlist.git
     branch: manifest
     private_key: ((gitea.id_ed25519))
 - name: releases
   type: http-resource
   source:
-    url: https://gitea.redxef.at/api/v1/repos/redxef/jellyfin-smart-playlist/releases
+    url: https://git.redxef.at/api/v1/repos/redxef/jellyfin-smart-playlist/releases
     method: get
     auth:
       basic:
@@ -32,7 +32,7 @@ resources:
 - name: artifact
   type: http-resource
   source:
-    url: https://gitea.redxef.at/api/v1/repos/redxef/jellyfin-smart-playlist/releases/((.:release_id))/assets
+    url: https://git.redxef.at/api/v1/repos/redxef/jellyfin-smart-playlist/releases/((.:release_id))/assets
     method: get
     auth:
       basic:

examples.md

@@ -0,0 +1,99 @@
+# Examples
+
+- `Favourite Pop`: A playlist
+  containing all favourite items of the genre pop.
+  ```
+  Id: Favourite Pop
+  Name: Favourite Pop
+  Program: |
+    (and (is-type "Audio") (is-favorite) (is-genre "pop" (genre-list)))
+  ```
+- `Electro Swing`: A playlist containing all items
+  which have a genre that contains "electro" and a
+  genre that contains "swing". It will only include
+  albums and single tracks.
+  ```
+  Id: Electro Swing
+  Name: Electro Swing
+  Program: |
+    (let
+      (g (genre-list))
+      (and
+        (or
+          (is-type "Audio")
+          (is-type "MusicAlbum"))
+        (is-genre "electro" g)
+        (is-genre "swing" g)))
+  ```
+
+- `All of Seeed`: A playlist containing all items by artist `Seeed`,
+  useless, since you also can just navigate to the artist to play all
+  their songs, but a good example.
+  ```
+  Id: Seeed
+  Name: Seeed
+  Program: |
+    (let
+      (parent
+        (invoke-generic *item* "FindParent" nil (list "MediaBrowser.Controller.Entities.Audio.MusicArtist, MediaBrowser.Controller")))
+      (cond
+        ((null parent) nil)
+        (t (string= (car (getitems parent "Name")) "Haller"))))
+  ```
+  or simplified with definitions contained in the preamble:
+  ```
+  Id: Seeed
+  Name: Seeed
+  Program: |
+    (let
+      (parent
+        (find-parent "MediaBrowser.Controller.Entities.Audio.MusicArtist, MediaBrowser.Controller"))
+      (cond
+        ((null parent) nil)
+        (t (string= (car (getitems parent "Name")) "Seeed"))))
+
+  ```
+
+- `Artists`: A playlist including everything from a list of artists.
+  ```
+  Id: Artists
+  Name: Artists
+  Program: >-
+    (begin
+      (define *include-artists* '(
+        "seeed"
+        "juli"
+        "falco"
+        "peter fox"
+        "alligatoah"
+        "kraftklub"
+        "wanda"
+        "annennaykantereit"
+        "feine sahne fischfilet"
+        "madsen"
+        "wiener blond"
+        "die toten hosen"
+        "die ärzte"
+        "wir sind helden"
+      ))
+      (define my-prefilter-only-tracks
+        (lambda nil
+          (and
+            (is-type "Audio")
+            (not (name-contains "live"))
+            (not (name-contains "acoustic"))
+            (not (name-contains "instrumental"))
+            (not (name-contains "remix")))))
+      (and
+        (my-prefilter-only-tracks)
+        (is-favourite)
+        (any
+          (lambda
+            (i)
+            ;; the `(and (find-artist)` is here to prevent null violations.
+            (and (find-artist) (string= i (lower (get-name (find-artist))))))
+          *include-artists*)))
+  SortProgram: (begin (shuf *items*))
+  Filename: /config/data/smartplaylists/German.yaml
+  Enabled: true
+  ```

examples/a1d02dee-f1da-4472-bee3-f568c15c8360.json

@@ -1,5 +0,0 @@
-{
-  "Id": "a1d02dee-f1da-4472-bee3-f568c15c8360",
-  "Name": "Favourite Pop",
-  "Program": "(and (invoke item 'IsFavoriteOrLiked' (user)) (find 'Pop' (car (getitems item 'Genres'))))"
-}

examples/index.md

@@ -1,4 +0,0 @@
-# Examples
-
-* [Favourite Pop](a1d02dee-f1da-4472-bee3-f568c15c8360.json): A Playlist
-  containing all favourite items of the genre pop.

lisp.md

@@ -0,0 +1,129 @@
+# The lisp interpreter
+
+The interpreter is a lisp-like language used to build the filter
+expressions.
+
+## Builtins
+
+**atom**: check if a receive value is a atom. `(atom 1)`
+
+**eq**: check if two values are equal. `(eq (quote a) (quote a))`
+
+**car**: get the first item of the cons.
+
+**cdr**: get the remainder of the list.
+
+**cons**: create a new cons. `(cons 1 2)`
+
+**begin**: evaluate a series of statements, returning the result of the
+last one. `(begin t nil)`
+
+**+-\*/%**: arithmetic operations for integers. `(+ 1 2)`
+
+**=**, **!=**, **<**, **<=**, **>**, **>=**: compare two integers. `(> 1 2)`
+
+**not**: negate the given value. `nil -> t`, everything else will be `nil`. `(not (quote a))`
+
+**string=**, **string!=**, **string<**, **string<=**, **string>**, **string>=**: compare two strings. `(> "1" "2")`
+
+**haskeys**: takes any object and a variadic number of arguments (strings) and
+returns a list with either `t` or `nil` describing if a corresponding property/field/method
+with that name exists on the object. `(haskeys mystring "Length")`
+
+**getitems**: takes any object and a variadic number of arguments
+(strings) and returns the values of the fields/properties. `(getitems mystring "Length" "Chars")`
+
+**invoke**: takes 3 arguments and invokes the method defined on the
+object.
+
+The first argument is the object on which to invoke the method, the
+second one is the name of the method and the third one is a list of
+arguments to pass to the method. `(invoke mystring "Lower" nil)`
+
+**invoke-generic**: the same as **invoke**, but takes a fourth
+argument, a list of string describing the types for the generic method.
+`(invoke-generic mybaseitem "FindParent" nil (list "MediaBrowser.Controller.Entities.Audio.MusicArtist, MediaBrowser.Controller"))`
+
+**random**: gives a random integer. `(random)`
+
+**shuffle**: shuffles a list. `(shuffle (list 1 2 3 4))`
+
+**quote**: quotes a value. `(quote a)`
+
+**eval**: evaluates a expression. `(eval (quote a))`
+
+**cond**: checks conditions and evaluates the corresponding expression.
+```
+(cond
+  ((> 1 2) t)
+  (t f))
+```
+
+**if**: a conditional. `(if t 1 2)`
+
+**define**: defines a new symbol. `(define foo 1)`, `(define add (lambda (a b) (+ a b)))`
+
+**let**: define variables in the let context and evaluate the last
+expression. `(let (a 1) (b 2) (+ a b))`
+
+**let\***: the same as **let**, but allows to reference variables
+defined earlier in the let statement. `(let* (a 1) (b (+ 2 a)) (+ a b))`
+
+**apply**: call a function with the specified arguments. `(apply + (list 1 2))`
+
+**and**: evaluate the given expressions in order, if any one of them
+evaluates to `nil` return early with that value, otherwise return the
+last value. `(and 1 2 nil 3)`
+
+**or**: return `nil` if all arguments evaluate to `nil` otherwise the
+first non-nil value.
+
+## Derived builtins
+
+**null**: the same as **not**. Can be useful to indicate semantics of a
+program.
+
+**list**: create a list from the given arguments. `(list 1 2 3)`
+
+**find**: find if an item is in the given list and return it, otherwise
+return `nil`. `(find 4 (list 1 2 3 4 5 6 7))`
+
+**map**: apply a function to every item in the list. `(map (lambda (x) (* 2 x)) (list 1 2 3))`
+
+**fold**: also known as reduce. Apply the function to a sequence of
+values, reducing the sequence to a single item. It takes a initial value
+which is returned for empty lists. `(fold (lambda (a b) (+ a b)) 0 (list 1 2 3 4))`
+
+**any**: equivalent to `(apply or (map function list))`.
+`(any (lambda (a) (% a 2)) (list 2 4 6 7 8))`
+
+**all**: equivalent to `(apply and (map function list))`.
+`(all (lambda (a) (% a 2)) (list 2 4 6 7 8))`
+
+**append**: append an item to the given list. `(append (list 1 2 3) 4)`
+
+**qsort**: quicksort, takes a comparison function and the list.
+`(qsort (lambda (a b) (> a b)) (list 1 2 6 4 9 1 19 0))`
+
+**rand**: get a random integer. Takes either zero, one or two arguments.
+If zero arguments are given it gives a random integer from all possibly
+representable integers. If one argument is given it gives a integer
+between `0` (inclusive) and `n` (exclusive). If two arguments are given
+it gives a integer between `a` (inclusive) and `b` (exclusive).
+
+**shuf**: same as **shuffle**.
+
+## Pre-defined convenience functions
+
+- **lower**: lowercases a string (`(eq (lower "SomeString") "somestring")`)
+- **is-genre**: check if the item is of this genre, partial matches
+  allowed, the example filter would match the genre "Nu-Metal" (`(is-genre "metal" (genre-list))`)
+- **is-genre-exact**: the same as `is-genre`, but does not match paritally
+- **is-favorite**: matches a favorite item (`(is-favorite)`)
+- **is-type**: matches the type of item look at
+  [BaseItemKind.cs](https://github.com/jellyfin/jellyfin/blob/master/Jellyfin.Data/Enums/BaseItemKind.cs)
+  for a list of items. The plugin has enabled support for `Audio, MusicAlbum, Playlist` (`(is-type "Audio")`)
+- **logd**, **logi**, **logw**, **loge**: write to the logger with the respective levels (`debug`, `information`, `warning`, `error`).
+  Takes the same arguments as `Logger.LogInformation(...)`.
+
+And many more.