// JavaScript Document

function URLEncode( plaintext ) {
	var SAFECHARS = "0123456789" +									// Numeric
									"ABCDEFGHIJKLMNOPQRSTUVWXYZ" +	// Alphabetic
									"abcdefghijklmnopqrstuvwxyz" +
									"-_.!~*\'()";										// RFC2396 Mark characters
	var HEX = "0123456789ABCDEF";
	var encoded = "";
	
	for( var i = 0; i < plaintext.length; i++ ) {
		var ch = plaintext.charAt(i);
	  if( ch == " " ) {
			encoded += "+";															// x-www-urlencoded, rather than %20
		} else if( SAFECHARS.indexOf( ch ) != -1 ) {
		  encoded += ch;
		} else {
		  var charCode = ch.charCodeAt( 0 );
			if( charCode > 255 ) {
				alert( "Unicode Character '" 
          			+ ch 
      	        + "' cannot be encoded using standard URL encoding.\n" 
								+ "(URL encoding only supports 8-bit characters.)\n" 
								+ "A space (+) will be substituted." );
				encoded += "+";
			} else {
				encoded += "%";
				encoded += HEX.charAt( ( charCode >> 4 ) & 0xF );
				encoded += HEX.charAt( charCode & 0xF );
			}
		}
	}

	return encoded;
};
		
function openPopup( imageType, imageFile, imageWidth, imageHeight ) {
		var ID = "imagePopup";
		var URL = "popup_image.php";
		URL += "?article_type="+imageType+"&image="+URLEncode( imageFile );
			
		eval( "page"+ID+" = window.open( '"+URL+"', '"+ID+"', 'toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=0,width="+( 40+imageWidth )+",height="+( 40+imageHeight )+"' );" );
};