using System;
using System.Globalization;

using HeuristicLab.Common;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Problems.ProgramSynthesis {
  /// <summary>
  /// Pushes the sum of the top two items.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.+",
    "Pushes the sum of the top two items.")]
  [StorableClass]
  public class FloatAddExpression : StatelessExpression {
    public FloatAddExpression() { }
    [StorableConstructor]
    protected FloatAddExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = second + first;

      if (double.IsPositiveInfinity(result)) result = double.MaxValue;
      if (double.IsNegativeInfinity(result)) result = double.MinValue;

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the difference of the top two items; that is, the second item minus the top item.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.-",
    "Pushes the difference of the top two items; that is, the second item minus the top item.")]
  [StorableClass]
  public class FloatSubtractExpression : StatelessExpression {
    public FloatSubtractExpression() { }
    [StorableConstructor]
    protected FloatSubtractExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = second - first;

      if (double.IsPositiveInfinity(result)) result = double.MaxValue;
      if (double.IsNegativeInfinity(result)) result = double.MinValue;

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the product of the top two items.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.*",
    "Pushes the product of the top two items.")]
  [StorableClass]
  public class FloatMultiplyExpression : StatelessExpression {
    public FloatMultiplyExpression() { }
    [StorableConstructor]
    protected FloatMultiplyExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = second * first;

      if (double.IsPositiveInfinity(result)) result = double.MaxValue;
      if (double.IsNegativeInfinity(result)) result = double.MinValue;

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the quotient of the top two items; that is, the second item divided by the top item.
  /// If the top item is zero this acts as a NOOP.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT./",
    "Pushes the quotient of the top two items; that is, the second item divided by the top item. If the top item is zero this acts as a NOOP.")]
  [StorableClass]
  public class FloatDivideExpression : StatelessExpression {
    public FloatDivideExpression() { }
    [StorableConstructor]
    protected FloatDivideExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2 || interpreter.FloatStack.Top.IsAlmost(0);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = second / first;

      if (double.IsPositiveInfinity(result)) result = double.MaxValue;
      if (double.IsNegativeInfinity(result)) result = double.MinValue;

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the second stack item modulo the top stack item. If the top item is zero this acts as a NOOP.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.%",
    "Pushes the second stack item modulo the top stack item. If the top item is zero this acts as a NOOP.")]
  [StorableClass]
  public class FloatModuloExpression : StatelessExpression {
    public FloatModuloExpression() { }
    [StorableConstructor]
    protected FloatModuloExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2 || interpreter.FloatStack.Top.IsAlmost(0);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = second % first;

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the minimum of the top two items.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.MIN",
    "Pushes the minimum of the top two items.")]
  [StorableClass]
  public class FloatMinExpression : StatelessExpression {
    public FloatMinExpression() { }
    [StorableConstructor]
    protected FloatMinExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = Math.Min(second, first);

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the maximum of the top two items.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.MAX",
    "Pushes the maximum of the top two items.")]
  [StorableClass]
  public class FloatMaxExpression : StatelessExpression {
    public FloatMaxExpression() { }
    [StorableConstructor]
    protected FloatMaxExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Pop();
      var second = interpreter.FloatStack.Top;
      var result = Math.Max(second, first);

      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes TRUE onto the BOOLEAN stack if the second item is less than the top item, or FALSE otherwise.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.<",
    "Pushes TRUE onto the BOOLEAN stack if the second item is less than the top item, or FALSE otherwise.",
    StackTypes.Boolean)]
  [StorableClass]
  public class FloatSmallerThanExpression : StatelessExpression {
    public FloatSmallerThanExpression() { }
    [StorableConstructor]
    protected FloatSmallerThanExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Top;
      var second = interpreter.FloatStack[1];
      interpreter.FloatStack.Remove(2);

      var result = second < first;
      interpreter.BooleanStack.Push(result);
    }
  }

  /// <summary>
  /// Pushes TRUE onto the BOOLEAN stack if the second item is less than the top item, or FALSE otherwise.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.<=",
    "Pushes TRUE onto the BOOLEAN stack if the second item is less than the top item, or FALSE otherwise.",
    StackTypes.Boolean)]
  [StorableClass]
  public class FloatSmallerThanOrEqualExpression : StatelessExpression {
    public FloatSmallerThanOrEqualExpression() { }
    [StorableConstructor]
    protected FloatSmallerThanOrEqualExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Top;
      var second = interpreter.FloatStack[1];
      interpreter.FloatStack.Remove(2);

      var result = second < first || second.IsAlmost(first);
      interpreter.BooleanStack.Push(result);
    }
  }

  /// <summary>
  /// Pushes TRUE onto the BOOLEAN stack if the second item is greater than the top item, or FALSE otherwise.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.>",
    "Pushes TRUE onto the BOOLEAN stack if the second item is greater than the top item, or FALSE otherwise.",
    StackTypes.Boolean)]
  [StorableClass]
  public class FloatGreaterThanExpression : StatelessExpression {
    public FloatGreaterThanExpression() { }
    [StorableConstructor]
    protected FloatGreaterThanExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Top;
      var second = interpreter.FloatStack[1];
      interpreter.FloatStack.Remove(2);

      var result = second > first;
      interpreter.BooleanStack.Push(result);
    }
  }

  /// <summary>
  /// Pushes TRUE onto the BOOLEAN stack if the second item is greater than or equal to the top item, or FALSE otherwise.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.>=",
    "Pushes TRUE onto the BOOLEAN stack if the second item is greater than or equal to the top item, or FALSE otherwise.",
    StackTypes.Boolean)]
  [StorableClass]
  public class FloatGreaterThanOrEqualExpression : StatelessExpression {
    public FloatGreaterThanOrEqualExpression() { }
    [StorableConstructor]
    protected FloatGreaterThanOrEqualExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.FloatStack.Count < 2;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var first = interpreter.FloatStack.Top;
      var second = interpreter.FloatStack[1];
      interpreter.FloatStack.Remove(2);

      var result = second > first || second.IsAlmost(first);
      interpreter.BooleanStack.Push(result);
    }
  }

  /// <summary>
  /// Pushes the sine of the top item.
  /// </summary>
  [PushExpression(StackTypes.Float, "FLOAT.SIN", "Pushes the sine of the top item.")]
  [StorableClass]
  public class FloatSineExpression : StatelessExpression {
    public FloatSineExpression() { }
    [StorableConstructor]
    protected FloatSineExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      var result = Math.Sin(interpreter.FloatStack.Top);
      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes the cosine of the top item.
  /// </summary>
  [PushExpression(StackTypes.Float, "FLOAT.COS", "Pushes the cosine of the top item.")]
  [StorableClass]
  public class FloatCosineExpression : StatelessExpression {
    public FloatCosineExpression() { }
    [StorableConstructor]
    protected FloatCosineExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      var result = Math.Cos(interpreter.FloatStack.Top);
      interpreter.FloatStack.Top = result;
    }
  }

  /// <summary>
  /// Pushes 1 if the top BOOLEAN is TRUE, or 0 if the top BOOLEAN is FALSE.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.FROMBOOLEAN",
    "Pushes 1 if the top BOOLEAN is TRUE, or 0 if the top BOOLEAN is FALSE.",
    StackTypes.Boolean)]
  [StorableClass]
  public class FloatFromBooleanExpression : StatelessExpression {
    public FloatFromBooleanExpression() { }
    [StorableConstructor]
    protected FloatFromBooleanExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      var condition = interpreter.BooleanStack.Pop();
      var value = condition ? 1 : 0;

      interpreter.FloatStack.Push(value);
    }
  }

  /// <summary>
  /// Pushes a floating point version of the top INTEGER.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.FROMINTEGER",
    "Pushes a floating point version of the top INTEGER.",
    StackTypes.Integer)]
  [StorableClass]
  public class FloatFromIntegerExpression : StatelessExpression {
    public FloatFromIntegerExpression() { }
    [StorableConstructor]
    protected FloatFromIntegerExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      var value = (double)interpreter.IntegerStack.Pop();
      interpreter.FloatStack.Push(value);
    }
  }

  /// <summary>
  /// Pushes the result of truncating the top CHAR.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.FROMCHAR",
    "Pushes the result of truncating the top CHAR.",
    StackTypes.Char)]
  [StorableClass]
  public class FloatFromCharExpression : StatelessExpression {
    public FloatFromCharExpression() { }
    [StorableConstructor]
    protected FloatFromCharExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      return interpreter.CharStack.IsEmpty;
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var value = interpreter.CharStack.Pop();
      interpreter.FloatStack.Push(value);
    }
  }

  /// <summary>
  /// Pushes the result of parsing the top STRING.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.FROMSTRING",
    "Pushes the result of parsing the top STRING.",
    StackTypes.String)]
  [StorableClass]
  public class FloatFromStringExpression : StatelessExpression {
    public FloatFromStringExpression() { }
    [StorableConstructor]
    protected FloatFromStringExpression(bool deserializing) : base(deserializing) { }

    public override bool IsNoop(IInternalPushInterpreter interpreter) {
      double tmp;
      return interpreter.StringStack.IsEmpty ||
             interpreter.StringStack.Top.Length == 0 ||
             !double.TryParse(
               interpreter.StringStack.Top,
               NumberStyles.AllowDecimalPoint | NumberStyles.Float,
               CultureInfo.InvariantCulture,
               out tmp);
    }

    public override void Eval(IInternalPushInterpreter interpreter) {
      var str = interpreter.StringStack.Pop();
      var value = double.Parse(str, NumberStyles.AllowDecimalPoint | NumberStyles.Float, CultureInfo.InvariantCulture);

      interpreter.FloatStack.Push(value);
    }
  }

  /// <summary>
  /// Pushes the result of increasing the top INTEGER by 1.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.INC",
    "Pushes the result of increasing the top INTEGER by 1.")]
  [StorableClass]
  public class FloatIncExpression : StatelessExpression {
    public FloatIncExpression() { }
    [StorableConstructor]
    protected FloatIncExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      interpreter.FloatStack.Top += 1;
    }
  }

  /// <summary>
  /// Pushes the result of decreasing the top INTEGER by 1.
  /// </summary>
  [PushExpression(
    StackTypes.Float,
    "FLOAT.DEC",
    "Pushes the result of decreasing the top INTEGER by 1.")]
  [StorableClass]
  public class FloatDecExpression : StatelessExpression {
    public FloatDecExpression() { }
    [StorableConstructor]
    protected FloatDecExpression(bool deserializing) : base(deserializing) { }

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

    public override void Eval(IInternalPushInterpreter interpreter) {
      interpreter.FloatStack.Top -= 1;
    }
  }
}