using System;
using System.Collections.Generic;
using System.Globalization;
using Microsoft.Xna.Framework;

namespace TwoMGFX.TPGParser
{
	public static class ParseTreeTools
	{
        public static float ParseFloat(string value)
        {
            // Remove all whitespace and trailing F or f.
            value = value.Replace(" ", "");
            value = value.TrimEnd('f', 'F');
            return float.Parse(value, NumberStyles.Float, CultureInfo.InvariantCulture);
        }

        public static int ParseInt(string value)
        {
            // We read it as a float and cast it down to
            // an integer to match Microsoft FX behavior.
            return (int)Math.Floor(ParseFloat(value));
        }
       
		public static bool ParseBool(string value)
		{
		    if (value.ToLowerInvariant() == "true" || value == "1")
				return true;
		    if (value.ToLowerInvariant() == "false" || value == "0")
		        return false;

		    throw new Exception("Invalid boolean value '" + value + "'");
		}

	    public static Color ParseColor(string value)
	    {
	        var hexValue = Convert.ToUInt32(value, 16);

	        byte r, g, b, a;
	        if (value.Length == 8)
	        {
	            r = (byte) ((hexValue >> 16) & 0xFF);
                g = (byte) ((hexValue >> 8) & 0xFF);
                b = (byte) ((hexValue >> 0) & 0xFF);
	            a = 255;
	        }
	        else if (value.Length == 10)
	        {
                r = (byte) ((hexValue >> 24) & 0xFF);
                g = (byte) ((hexValue >> 16) & 0xFF);
                b = (byte) ((hexValue >> 8) & 0xFF);
                a = (byte) ((hexValue >> 0) & 0xFF);
	        }
	        else
	        {
	            throw new NotSupportedException();
	        }

            return new Color(r, g, b, a);
	    }        
    }
}