/*************************************************************
* NLB Background Color Fader v1.0
* Author: Justin Barlow - www.netlobo.com
*
* Description:
* The Background Color Fader allows you to gradually fade the
* background of any HTML element.
*
* Usage:
* Call the Background Color Fader as follows:
* NLBfadeBg( elementId, startBgColor, endBgColor, fadeTime );
*
* Description of Parameters
* elementId - The id of the element you wish to fade the
* background of.
* startBgColor - The background color you wish to start the
* fade from.
* endBgColor - The background color you want to fade to.
* fadeTime - The duration of the fade in milliseconds.
*************************************************************/

var nlbFade_hextable = [ '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' ]; // used for RGB to Hex and Hex to RGB conversions
var nlbFade_elemTable = new Array( ); // global array to keep track of faded elements
var nlbFade_t = new Array( ); // global array to keep track of fading timers
function NLBfadeBg( elementId, startBgColor, endBgColor, fadeTime )
{
 var timeBetweenSteps = Math.round( Math.max( fadeTime / 300, 30 ) );
 var nlbFade_elemTableId = nlbFade_elemTable.indexOf( elementId );
 if( nlbFade_elemTableId > -1 )
 {
 for( var i = 0; i < nlbFade_t[nlbFade_elemTableId].length; i++ )
 clearTimeout( nlbFade_t[nlbFade_elemTableId][i] );
 }
 else
 {
 nlbFade_elemTable.push( elementId );
 nlbFade_elemTableId = nlbFade_elemTable.indexOf( elementId );
 }
 var startBgColorRGB = hexToRGB( startBgColor );
 var endBgColorRGB = hexToRGB( endBgColor );
 var diffRGB = new Array( );
 for( var i = 0; i < 3; i++ )
 diffRGB[i] = endBgColorRGB[i] - startBgColorRGB[i];
 var steps = Math.ceil( fadeTime / timeBetweenSteps );
 var nlbFade_s = new Array( );
 for( var i = 1; i <= steps; i++ )
 {
 var changes = new Array( );
 for( var j = 0; j < diffRGB.length; j++ )
 changes[j] = startBgColorRGB[j] + Math.round( ( diffRGB[j] / steps ) * i );
 if( i == steps )
 nlbFade_s[i - 1] = setTimeout( 'document.getElementById("'+elementId+'").style.backgroundColor = "'+endBgColor+'";', timeBetweenSteps*(i-1) );
 else
 nlbFade_s[i - 1] = setTimeout( 'document.getElementById("'+elementId+'").style.backgroundColor = "'+RGBToHex( changes )+'";', timeBetweenSteps*(i-1) );
 }
 nlbFade_t[nlbFade_elemTableId] = nlbFade_s;
}
function hexToRGB( hexVal )
{
 hexVal = hexVal.toUpperCase( );
 if( hexVal.substring( 0, 1 ) == '#' )
 hexVal = hexVal.substring( 1 );
 var hexArray = new Array( );
 var rgbArray = new Array( );
 hexArray[0] = hexVal.substring( 0, 2 );
 hexArray[1] = hexVal.substring( 2, 4 );
 hexArray[2] = hexVal.substring( 4, 6 );
 for( var k = 0; k < hexArray.length; k++ )
 {
 var num = hexArray[k];
 var res = 0;
 var j = 0;
 for( var i = num.length - 1; i >= 0; i-- )
 res += parseInt( nlbFade_hextable.indexOf( num.charAt( i ) ) ) * Math.pow( 16, j++ );
 rgbArray[k] = res;
 }
 return rgbArray;
}
function RGBToHex( rgbArray )
{
 var retval = new Array( );
 for( var j = 0; j < rgbArray.length; j++ )
 {
 var result = new Array( );
 var val = rgbArray[j];
 var i = 0;
 while( val > 16 )
 {
 result[i++] = val%16;
 val = Math.floor( val/16 );
 }
 result[i++] = val%16;
 var out = '';
 for( var k = result.length - 1; k >= 0; k-- )
 out += nlbFade_hextable[result[k]];
 retval[j] = padLeft( out, '0', 2 );
 }
 out = '#';
 for( var i = 0; i < retval.length; i++ )
 out += retval[i];
 return out;
}
if (!Array.prototype.indexOf) {
 Array.prototype.indexOf = function( val, fromIndex ) {
 if( typeof( fromIndex ) != 'number' ) fromIndex = 0;
 for( var index = fromIndex, len = this.length; index < len; index++ )
 if( this[index] == val ) return index;
 return -1;
 }
}
function padLeft( string, character, paddedWidth )
{
 if( string.length >= paddedWidth )
 return string;
 else
 {
 while( string.length < paddedWidth )
 string = character + string;
 }
 return string;
}