FunctionMultiVariate.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading.Tasks;
using Waher.Runtime.Collections;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Abstraction.Sets;
using Waher.Script.Exceptions;
using Waher.Script.Objects;
 
namespace Waher.Script.Model
{
    public abstract class FunctionMultiVariate : Function
    {
        protected static readonly ArgumentType[] argumentTypes0 = Array.Empty<ArgumentType>();
 
        protected static readonly ArgumentType[] argumentTypes1Normal = new ArgumentType[] { ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes1Vector = new ArgumentType[] { ArgumentType.Vector };
 
        protected static readonly ArgumentType[] argumentTypes1Matrix = new ArgumentType[] { ArgumentType.Matrix };
 
        protected static readonly ArgumentType[] argumentTypes1Set = new ArgumentType[] { ArgumentType.Set };
 
        protected static readonly ArgumentType[] argumentTypes2Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes3Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes4Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes5Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes6Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes7Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes8Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes9Normal = new ArgumentType[] { ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal, ArgumentType.Normal };
 
        protected static readonly ArgumentType[] argumentTypes1Scalar = new ArgumentType[] { ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes2Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes3Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes4Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes5Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes6Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes7Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes8Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
        protected static readonly ArgumentType[] argumentTypes9Scalar = new ArgumentType[] { ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar, ArgumentType.Scalar };
 
 
        private readonly ScriptNode[] arguments;
        private readonly ArgumentType[] argumentTypes;
        private readonly bool allNormal;
        private readonly int nrArguments;
        private bool isAsync;
 
        public FunctionMultiVariate(ScriptNode[] Arguments, ArgumentType[] ArgumentTypes, int Start, int Length, Expression Expression)
            : base(Start, Length, Expression)
        {
            if (Arguments.Length != ArgumentTypes.Length)
                throw new ArgumentException("Size of ArgumentTypes must match the size of Arguments.", nameof(ArgumentTypes));
 
            this.arguments = Arguments;
            this.arguments?.SetParent(this);
 
            this.argumentTypes = ArgumentTypes;
            this.nrArguments = this.arguments.Length;
 
            this.allNormal = true;
            foreach (ArgumentType Type in this.argumentTypes)
            {
                if (Type != ArgumentType.Normal)
                {
                    this.allNormal = false;
                    break;
                }
            }
 
            this.CalcIsAsync();
        }
 
        private void CalcIsAsync()
        {
            this.isAsync = false;
 
            for (int i = 0; i < this.nrArguments; i++)
            {
                if (this.arguments[i]?.IsAsynchronous ?? false)
                {
                    this.isAsync = true;
                    break;
                }
            }
        }
 
        public ScriptNode[] Arguments => this.arguments;
 
        public ArgumentType[] ArgumentTypes => this.argumentTypes;
 
        public override bool IsAsynchronous => this.isAsync;
 
        public override IElement Evaluate(Variables Variables)
        {
            IElement[] Arg = new IElement[this.nrArguments];
            ScriptNode Node;
            int i;
 
            for (i = 0; i < this.nrArguments; i++)
            {
                Node = this.arguments[i];
                if (Node is null)
                    Arg[i] = ObjectValue.Null;
                else
                    Arg[i] = Node.Evaluate(Variables);
            }
 
            if (this.allNormal)
                return this.Evaluate(Arg, Variables);
            else
                return this.EvaluateCanonicalExtension(Arg, Variables);
        }
 
        public override async Task<IElement> EvaluateAsync(Variables Variables)
        {
            if (!this.IsAsynchronous)
                return this.Evaluate(Variables);
 
            IElement[] Arg = new IElement[this.nrArguments];
            ScriptNode Node;
            int i;
 
            for (i = 0; i < this.nrArguments; i++)
            {
                Node = this.arguments[i];
                if (Node is null)
                    Arg[i] = ObjectValue.Null;
                else
                    Arg[i] = await Node.EvaluateAsync(Variables);
            }
 
            if (this.allNormal)
                return await this.EvaluateAsync(Arg, Variables);
            else
                return await this.EvaluateCanonicalExtensionAsync(Arg, Variables);
        }
 
        private IElement EvaluateCanonicalExtension(IElement[] Arguments, Variables Variables)
        {
            int i, j;
 
            this.Prepare(Arguments, out Encapsulation Encapsulation, out int Dimension, out IEnumerator<IElement>[] e);
 
            try
            {
                if (!(Encapsulation is null))
                {
                    ChunkedList<IElement> Result = new ChunkedList<IElement>();
                    IElement[] Arguments2 = new IElement[this.nrArguments];
 
                    for (j = 0; j < Dimension; j++)
                    {
                        for (i = 0; i < this.nrArguments; i++)
                        {
                            if (e[i] is null || !e[i].MoveNext())
                                Arguments2[i] = Arguments[i];
                            else
                                Arguments2[i] = e[i].Current;
                        }
 
                        Result.Add(this.EvaluateCanonicalExtension(Arguments2, Variables));
                    }
 
                    return Encapsulation(Result, this);
                }
                else
                    return this.Evaluate(Arguments, Variables);
            }
            finally
            {
                for (i = 0, j = e?.Length ?? 0; i < j; i++)
                    e[i]?.Dispose();
            }
        }
 
        private void Prepare(IElement[] Arguments, out Encapsulation Encapsulation, out int Dimension, out IEnumerator<IElement>[] e)
        {
            ICollection<IElement> ChildElements;
            IElement Argument;
            IMatrix M;
            ISet S;
            IVectorSpaceElement V;
            int i, j;
 
            e = new IEnumerator<IElement>[this.nrArguments];
            Encapsulation = null;
            Dimension = -1;
 
            for (i = 0; i < this.nrArguments; i++)
            {
                Argument = Arguments[i];
 
                switch (this.argumentTypes[i])
                {
                    case ArgumentType.Normal:
                        e[i] = null;
                        break;
 
                    case ArgumentType.Scalar:
                        if (Argument.IsScalar)
                            e[i] = null;
                        else
                        {
                            ChildElements = Argument.ChildElements;
 
                            if (Dimension < 0)
                                Dimension = ChildElements.Count;
                            else if (ChildElements.Count != Dimension)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            e[i] = ChildElements.GetEnumerator();
                            if (Encapsulation is null)
                                Encapsulation = Argument.Encapsulate;
                        }
                        break;
 
                    case ArgumentType.Vector:
                        if (Argument is IVector)
                            e[i] = null;
                        else if (!((M = Argument as IMatrix) is null))
                        {
                            if (Dimension < 0)
                                Dimension = M.Rows;
                            else if (M.Rows != Dimension)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            ChunkedList<IElement> Vectors = new ChunkedList<IElement>();
 
                            for (j = 0; j < Dimension; j++)
                                Vectors.Add(M.GetRow(j));
 
                            e[i] = Vectors.GetEnumerator();
                            if (Encapsulation is null)
                                Encapsulation = Operators.LambdaDefinition.EncapsulateToVector;
                        }
                        else if (!((S = Argument as ISet) is null))
                        {
                            int? Size = S.Size;
                            if (!Size.HasValue)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            if (Dimension < 0)
                                Dimension = Size.Value;
                            else if (Size.Value != Dimension)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            e[i] = S.ChildElements.GetEnumerator();
                            if (Encapsulation is null)
                                Encapsulation = Argument.Encapsulate;
                        }
                        else if (Argument.AssociatedObjectValue is IEnumerable Enumerable &&
                            !(Argument.AssociatedObjectValue is string) &&
                            !(Argument.AssociatedObjectValue is IDictionary<string, IElement>) &&
                            !(Argument.AssociatedObjectValue is IDictionary<string, object>))
                        {
                            Arguments[i] = Operators.Vectors.VectorDefinition.Encapsulate(Enumerable, false, this);
                            e[i] = null;
                        }
                        else
                        {
                            Arguments[i] = Operators.Vectors.VectorDefinition.Encapsulate(new IElement[] { Argument }, false, this);
                            e[i] = null;
                        }
                        break;
 
                    case ArgumentType.Set:
                        if (Argument is ISet)
                            e[i] = null;
                        else if (!((V = Argument as IVectorSpaceElement) is null))
                        {
                            Arguments[i] = Operators.Sets.SetDefinition.Encapsulate(V.ChildElements);
                            e[i] = null;
                        }
                        else if (!((M = Argument as IMatrix) is null))
                        {
                            if (Dimension < 0)
                                Dimension = M.Rows;
                            else if (M.Rows != Dimension)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            ChunkedList<IElement> Vectors = new ChunkedList<IElement>();
 
                            for (j = 0; j < Dimension; j++)
                                Vectors.Add(M.GetRow(j));
 
                            Arguments[i] = Argument = Operators.Sets.SetDefinition.Encapsulate(Vectors);
                            ChildElements = Argument.ChildElements;
 
                            e[i] = ChildElements.GetEnumerator();
                            if (Encapsulation is null)
                                Encapsulation = Operators.LambdaDefinition.EncapsulateToVector;
                        }
                        else if (Argument.AssociatedObjectValue is IEnumerable Enumerable &&
                            !(Argument.AssociatedObjectValue is string) &&
                            !(Argument.AssociatedObjectValue is IDictionary<string, IElement>) &&
                            !(Argument.AssociatedObjectValue is IDictionary<string, object>))
                        {
                            Arguments[i] = Operators.Sets.SetDefinition.Encapsulate(Enumerable);
                            e[i] = null;
                        }
                        else
                        {
                            Arguments[i] = Operators.Sets.SetDefinition.Encapsulate(new IElement[] { Argument });
                            e[i] = null;
                        }
                        break;
 
                    case ArgumentType.Matrix:
                        if (Argument is IMatrix)
                            e[i] = null;
                        else if (!((V = Argument as IVectorSpaceElement) is null))
                        {
                            Arguments[i] = Operators.Matrices.MatrixDefinition.Encapsulate(V.ChildElements, 1, V.Dimension, this);
                            e[i] = null;
                        }
                        else if (!((S = Argument as ISet) is null))
                        {
                            int? Size = S.Size;
                            if (!Size.HasValue)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            if (Dimension < 0)
                                Dimension = Size.Value;
                            else if (Size.Value != Dimension)
                                throw new ArgumentDimensionsInconsistentScriptException(this);
 
                            e[i] = S.ChildElements.GetEnumerator();
                            if (Encapsulation is null)
                                Encapsulation = Argument.Encapsulate;
                        }
                        else
                        {
                            Arguments[i] = Operators.Matrices.MatrixDefinition.Encapsulate(new IElement[] { Argument }, 1, 1, this);
                            e[i] = null;
                        }
                        break;
 
                    default:
                        throw new ScriptRuntimeException("Unhandled argument type.", this);
                }
            }
        }
 
        private async Task<IElement> EvaluateCanonicalExtensionAsync(IElement[] Arguments, Variables Variables)
        {
            int i, j;
 
            this.Prepare(Arguments, out Encapsulation Encapsulation, out int Dimension, out IEnumerator<IElement>[] e);
 
            try
            {
                if (!(Encapsulation is null))
                {
                    ChunkedList<IElement> Result = new ChunkedList<IElement>();
                    IElement[] Arguments2 = new IElement[this.nrArguments];
 
                    for (j = 0; j < Dimension; j++)
                    {
                        for (i = 0; i < this.nrArguments; i++)
                        {
                            if (e[i] is null || !e[i].MoveNext())
                                Arguments2[i] = Arguments[i];
                            else
                                Arguments2[i] = e[i].Current;
                        }
 
                        Result.Add(await this.EvaluateCanonicalExtensionAsync(Arguments2, Variables));
                    }
 
                    return Encapsulation(Result, this);
                }
                else
                    return await this.EvaluateAsync(Arguments, Variables);
            }
            finally
            {
                for (i = 0, j = e?.Length ?? 0; i < j; i++)
                    e[i]?.Dispose();
            }
        }
 
        public abstract IElement Evaluate(IElement[] Arguments, Variables Variables);
 
        public virtual Task<IElement> EvaluateAsync(IElement[] Arguments, Variables Variables)
        {
            return Task.FromResult(this.Evaluate(Arguments, Variables));
        }
 
        public override bool ForAllChildNodes(ScriptNodeEventHandler Callback, object State, SearchMethod Order)
        {
            int i;
 
            if (Order == SearchMethod.DepthFirst)
            {
                if (!this.arguments.ForAllChildNodes(Callback, State, Order))
                    return false;
            }
 
            ScriptNode Node;
            bool RecalcIsAsync = false;
 
            for (i = 0; i < this.nrArguments; i++)
            {
                Node = this.arguments[i];
                if (!(Node is null))
                {
                    bool b = !Callback(Node, out ScriptNode NewNode, State);
                    if (!(NewNode is null))
                    {
                        this.arguments[i] = NewNode;
                        NewNode.SetParent(this);
                        Node = NewNode;
 
                        RecalcIsAsync = true;
                    }
 
                    if (b || (Order == SearchMethod.TreeOrder && !Node.ForAllChildNodes(Callback, State, Order)))
                    {
                        if (RecalcIsAsync)
                            this.CalcIsAsync();
 
                        return false;
                    }
                }
            }
 
            if (RecalcIsAsync)
                this.CalcIsAsync();
 
            if (Order == SearchMethod.BreadthFirst)
            {
                if (!this.arguments.ForAllChildNodes(Callback, State, Order))
                    return false;
            }
 
            return true;
        }
 
        public override bool Equals(object obj)
        {
            return obj is FunctionMultiVariate O &&
                AreEqual(this.arguments, O.arguments) &&
                AreEqual(this.argumentTypes, O.argumentTypes) &&
                base.Equals(obj);
        }
 
        public override int GetHashCode()
        {
            int Result = base.GetHashCode();
            Result ^= Result << 5 ^ GetHashCode(this.arguments);
            Result ^= Result << 5 ^ GetHashCode(this.argumentTypes);
            return Result;
        }
 
    }
}