using System.Collections.Generic;

namespace HeuristicLab.Problems.ProgramSynthesis.Push.Expressions {
  using System.Linq;

  using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Attributes;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Interpreter;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Stack;

  /// <summary>
  /// Tells whether the top lit-type item is in the top type vector.
  /// </summary>
  /// <typeparam name="T"></typeparam>
  [StorableClass]
  public abstract class VectorContainsExpression<T> : StatelessExpression {
    protected VectorContainsExpression() { }
    [StorableConstructor]
    protected VectorContainsExpression(bool deserializing) : base(deserializing) { }

    protected bool IsNoop(IPushStack<IReadOnlyList<T>> vectorStack, IPushStack<T> literalStack) {
      return vectorStack.IsEmpty || literalStack.IsEmpty;
    }

    protected void Eval(IInternalPushInterpreter interpreter, IPushStack<IReadOnlyList<T>> vectorStack, IPushStack<T> literalStack, bool canOverride = false) {
      var vector = vectorStack.Pop();
      var literal = canOverride ? literalStack.Top : literalStack.Pop();
      var contains = vector.Contains(literal);

      if (canOverride) interpreter.BooleanStack.Top = contains;
      else interpreter.BooleanStack.Push(contains);
    }
  }

  [StorableClass]
  [PushExpression(
    StackTypes.IntegerVector,
    "INTEGER[].CONTAINS",
    "Tells whether the top INTEGER is in the top INTEGER[].",
    StackTypes.Integer | StackTypes.Boolean)]
  public class IntegerVectorContainsExpression : VectorContainsExpression<long> {
    public IntegerVectorContainsExpression() { }
    [StorableConstructor]
    protected IntegerVectorContainsExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return IsNoop(interpreter.IntegerVectorStack, interpreter.IntegerStack);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      Eval(interpreter, interpreter.IntegerVectorStack, interpreter.IntegerStack);
    }
  }

  [StorableClass]
  [PushExpression(
    StackTypes.FloatVector,
    "FLOAT[].CONTAINS",
    "Tells whether the top FLOAT is in the top FLOAT[].",
    StackTypes.Float | StackTypes.Boolean)]
  public class FloatVectorContainsExpression : VectorContainsExpression<double> {
    public FloatVectorContainsExpression() { }
    [StorableConstructor]
    protected FloatVectorContainsExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return IsNoop(interpreter.FloatVectorStack, interpreter.FloatStack);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      Eval(interpreter, interpreter.FloatVectorStack, interpreter.FloatStack);
    }
  }

  [StorableClass]
  [PushExpression(
    StackTypes.BooleanVector,
    "BOOLEAN[].CONTAINS",
    "Tells whether the top BOOLEAN is in the top BOOLEAN[].",
    StackTypes.Boolean)]
  public class BooleanVectorContainsExpression : VectorContainsExpression<bool> {
    public BooleanVectorContainsExpression() { }
    [StorableConstructor]
    protected BooleanVectorContainsExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return IsNoop(interpreter.BooleanVectorStack, interpreter.BooleanStack);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      Eval(interpreter, interpreter.BooleanVectorStack, interpreter.BooleanStack, true);
    }
  }

  [StorableClass]
  [PushExpression(
    StackTypes.StringVector,
    "STRING[].CONTAINS",
    "Tells whether the top STRING is in the top STRING[].",
    StackTypes.String | StackTypes.Boolean)]
  public class StringVectorContainsExpression : VectorContainsExpression<string> {
    public StringVectorContainsExpression() { }
    [StorableConstructor]
    protected StringVectorContainsExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return IsNoop(interpreter.StringVectorStack, interpreter.StringStack);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      Eval(interpreter, interpreter.StringVectorStack, interpreter.StringStack);
    }
  }

}