DateTimeLocal.cs

using System;
using System.Collections.Generic;
using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Model;
using Waher.Script.Objects;
 
namespace Waher.Script.Functions.DateAndTime
{
    public class DateTimeLocal : FunctionMultiVariate
    {
        public DateTimeLocal(ScriptNode String, int Start, int Length, Expression Expression)
            : base(new ScriptNode[] { String }, argumentTypes1Scalar, Start, Length, Expression)
        {
        }
 
        public DateTimeLocal(ScriptNode Year, ScriptNode Month, ScriptNode Day, int Start, int Length, Expression Expression)
            : base(new ScriptNode[] { Year, Month, Day }, argumentTypes3Scalar, Start, Length, Expression)
        {
        }
 
        public DateTimeLocal(ScriptNode Year, ScriptNode Month, ScriptNode Day, ScriptNode Hour, ScriptNode Minute, ScriptNode Second, 
            int Start, int Length, Expression Expression)
            : base(new ScriptNode[] { Year, Month, Day, Hour, Minute, Second }, argumentTypes6Scalar, Start, Length, Expression)
        {
        }
 
        public DateTimeLocal(ScriptNode Year, ScriptNode Month, ScriptNode Day, ScriptNode Hour, ScriptNode Minute, ScriptNode Second,
            ScriptNode MSecond, int Start, int Length, Expression Expression)
            : base(new ScriptNode[] { Year, Month, Day, Hour, Minute, Second, MSecond }, argumentTypes7Scalar, Start, Length, Expression)
        {
        }
 
        public override string FunctionName => nameof(DateTimeLocal);
 
        public override string[] DefaultArgumentNames
        {
            get { return new string[] { "Year", "Month", "Day", "Hour", "Minute", "Second", "MSecond" }; }
        }
 
        public override IElement Evaluate(IElement[] Arguments, Variables Variables)
        {
            int i, c = this.Arguments.Length;
 
            if (c == 1)
            {
                object Obj = Arguments[0].AssociatedObjectValue;
 
                if (Obj is System.DateTime TP)
                    return new DateTimeValue(TP.ToLocalTime());
                else if (Obj is System.DateTimeOffset TPO)
                    return new DateTimeValue(TPO.ToLocalTime().DateTime);
                else if (Obj is long L)
                    return new DateTimeValue(DateTime.FromInteger(L, DateTimeKind.Local));
                else if (Obj is double Dbl)
                    return new DateTimeValue(DateTime.FromInteger((long)Dbl, DateTimeKind.Local));
                else
                {
                    string s = Obj?.ToString() ?? string.Empty;
 
                    if (DateTime.TryParse(s, out TP))
                    {
                        if (TP.Kind != DateTimeKind.Local)
                            TP = new System.DateTime(TP.Year, TP.Month, TP.Day, TP.Hour, TP.Minute, TP.Second, TP.Millisecond, DateTimeKind.Local);
 
                        return new DateTimeValue(TP);
                    }
                    else
                        throw new ScriptRuntimeException("Unable to parse DateTime value: " + s, this);
                }
            }
 
            double[] d = new double[c];
            DoubleNumber n;
 
            for (i = 0; i < c; i++)
            {
                n = Arguments[i] as DoubleNumber;
                if (n is null)
                    throw new ScriptRuntimeException("Expected number arguments.", this);
 
                d[i] = n.Value;
            }
 
            switch (c)
            {
                case 3:
                    return new DateTimeValue(new System.DateTime((int)d[0], (int)d[1], (int)d[2], 0, 0, 0, DateTimeKind.Local));
 
                case 6:
                    return new DateTimeValue(new System.DateTime((int)d[0], (int)d[1], (int)d[2], (int)d[3], (int)d[4], (int)d[5], DateTimeKind.Local));
 
                case 7:
                    return new DateTimeValue(new System.DateTime((int)d[0], (int)d[1], (int)d[2], (int)d[3], (int)d[4], (int)d[5], (int)d[6], DateTimeKind.Local));
 
                default:
                    throw new ScriptRuntimeException("Invalid number of parameters.", this);
            }
        }
 
        public override PatternMatchResult PatternMatch(IElement CheckAgainst, Dictionary<string, IElement> AlreadyFound)
        {
            object Obj = CheckAgainst.AssociatedObjectValue;
 
            if (!(Obj is System.DateTime TP))
            {
                if (Obj is double d)
                    TP = DateTime.FromInteger((long)d, DateTimeKind.Local);
                else
                {
                    string s = CheckAgainst.AssociatedObjectValue?.ToString() ?? string.Empty;
 
                    if (!DateTime.TryParse(s, out TP))
                    {
                        if (long.TryParse(s, out long Ticks))
                            TP = DateTime.FromInteger(Ticks, DateTimeKind.Local);
                        else
                            return PatternMatchResult.NoMatch;
                    }
                }
            }
 
            TP = TP.ToLocalTime();
 
            int c = this.Arguments.Length;
            if (c == 1)
                return this.Arguments[0].PatternMatch(new DateTimeValue(TP), AlreadyFound);
 
            if (c < 3)
                return PatternMatchResult.NoMatch;
 
            PatternMatchResult Result = this.Arguments[0].PatternMatch(new DoubleNumber(TP.Year), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            Result = this.Arguments[1].PatternMatch(new DoubleNumber(TP.Month), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            Result = this.Arguments[2].PatternMatch(new DoubleNumber(TP.Day), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            if (c == 3)
                return TP.TimeOfDay == System.TimeSpan.Zero ? PatternMatchResult.Match : PatternMatchResult.NoMatch;
 
            if (c < 6)
                return PatternMatchResult.NoMatch;
 
            Result = this.Arguments[3].PatternMatch(new DoubleNumber(TP.Hour), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            Result = this.Arguments[4].PatternMatch(new DoubleNumber(TP.Minute), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            Result = this.Arguments[5].PatternMatch(new DoubleNumber(TP.Second), AlreadyFound);
            if (Result != PatternMatchResult.Match)
                return Result;
 
            if (c == 6)
                return TP.Millisecond == 0 ? PatternMatchResult.Match : PatternMatchResult.NoMatch;
 
            if (c != 7)
                return PatternMatchResult.NoMatch;
 
            return this.Arguments[6].PatternMatch(new DoubleNumber(TP.Millisecond), AlreadyFound);
        }
    }
}