/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

var YAHOO = function() { return {util: {}} } ();
YAHOO.util.Color = new function() {
  
  // Adapted from http://www.easyrgb.com/math.html
  // hsv values = 0 - 1
  // rgb values 0 - 255
  this.hsv2rgb = function (h, s, v) {
    var r, g, b;
    if ( s == 0 ) {
      r = v * 255;
      g = v * 255;
      b = v * 255;
    } else {

      // h must be < 1
      var var_h = h * 6;
      if ( var_h == 6 ) {
        var_h = 0;
      }

      //Or ... var_i = floor( var_h )
      var var_i = Math.floor( var_h );
      var var_1 = v * ( 1 - s );
      var var_2 = v * ( 1 - s * ( var_h - var_i ) );
      var var_3 = v * ( 1 - s * ( 1 - ( var_h - var_i ) ) );

      if ( var_i == 0 ) { 
        var_r = v; 
        var_g = var_3; 
        var_b = var_1;
      } else if ( var_i == 1 ) { 
        var_r = var_2;
        var_g = v;
        var_b = var_1;
      } else if ( var_i == 2 ) {
        var_r = var_1;
        var_g = v;
        var_b = var_3
      } else if ( var_i == 3 ) {
        var_r = var_1;
        var_g = var_2;
        var_b = v;
      } else if ( var_i == 4 ) {
        var_r = var_3;
        var_g = var_1;
        var_b = v;
      } else { 
        var_r = v;
        var_g = var_1;
        var_b = var_2
      }

      r = var_r * 255          //rgb results = 0 ÷ 255
      g = var_g * 255
      b = var_b * 255

      }
    return [Math.round(r), Math.round(g), Math.round(b)];
  };

  // added by Matthias Platzer AT knallgrau.at 
  this.rgb2hsv = function (r, g, b) {
      var r = ( r / 255 );                   //RGB values = 0 ÷ 255
      var g = ( g / 255 );
      var b = ( b / 255 );

      var min = Math.min( r, g, b );    //Min. value of RGB
      var max = Math.max( r, g, b );    //Max. value of RGB
      deltaMax = max - min;             //Delta RGB value

      var v = max;
      var s, h;
      var deltaRed, deltaGreen, deltaBlue;

      if ( deltaMax == 0 )                     //This is a gray, no chroma...
      {
         h = 0;                               //HSV results = 0 ÷ 1
         s = 0;
      }
      else                                    //Chromatic data...
      {
         s = deltaMax / max;

         deltaRed = ( ( ( max - r ) / 6 ) + ( deltaMax / 2 ) ) / deltaMax;
         deltaGreen = ( ( ( max - g ) / 6 ) + ( deltaMax / 2 ) ) / deltaMax;
         deltaBlue = ( ( ( max - b ) / 6 ) + ( deltaMax / 2 ) ) / deltaMax;

         if      ( r == max ) h = deltaBlue - deltaGreen;
         else if ( g == max ) h = ( 1 / 3 ) + deltaRed - deltaBlue;
         else if ( b == max ) h = ( 2 / 3 ) + deltaGreen - deltaRed;

         if ( h < 0 ) h += 1;
         if ( h > 1 ) h -= 1;
      }

      return [h, s, v];
  }

  this.rgb2hex = function (r,g,b) {
    return this.toHex(r) + this.toHex(g) + this.toHex(b);
  };

  this.hexchars = "0123456789ABCDEF";

  this.toHex = function(n) {
    n = n || 0;
    n = parseInt(n, 10);
    if (isNaN(n)) n = 0;
    n = Math.round(Math.min(Math.max(0, n), 255));

    return this.hexchars.charAt((n - n % 16) / 16) + this.hexchars.charAt(n % 16);
  };

  this.toDec = function(hexchar) {
    return this.hexchars.indexOf(hexchar.toUpperCase());
  };

  this.hex2rgb = function(str) { 
    var rgb = [];
    rgb[0] = (this.toDec(str.substr(0, 1)) * 16) + 
            this.toDec(str.substr(1, 1));
    rgb[1] = (this.toDec(str.substr(2, 1)) * 16) + 
            this.toDec(str.substr(3, 1));
    rgb[2] = (this.toDec(str.substr(4, 1)) * 16) + 
            this.toDec(str.substr(5, 1));
    // gLogger.debug("hex2rgb: " + str + ", " + rgb.toString());
    return rgb;
  };

  this.isValidRGB = function(a) { 
    if ((!a[0] && a[0] !=0) || isNaN(a[0]) || a[0] < 0 || a[0] > 255) return false;
    if ((!a[1] && a[1] !=0) || isNaN(a[1]) || a[1] < 0 || a[1] > 255) return false;
    if ((!a[2] && a[2] !=0) || isNaN(a[2]) || a[2] < 0 || a[2] > 255) return false;

    return true;
  };
}