/**
 * WebSnap jQuery plugin
 * 
 * A not-very-generic class for loading preview snapshots of urls
 * 
 * Usage: $('a.websnap').websnap(params); // initializes all links with class websnap
 * Params: url - the base url (where to find the websnap-controller)
 * 
 * @author Mikko Hämäläinen <mkoh@mkoh.net>
 */

(function($){
	var opts;

	$.fn.websnap = function(options){
		// build main options
		$.fn.websnap.opts = $.extend({}, $.fn.websnap.defaults, options);

		// initalize websnap
		$.fn.websnap.initialize();
		return this.each(function(){
			$(this).mouseover(function(event){

				var tPosX = event.pageX - 100;
				var tPosY = event.pageY + 20;
				
				$(this).websnap.start(this,[tPosX,tPosY]);
				return false;
			});
			$(this).mouseout(function(event){
				$(this).websnap.end(this);
				return false;
			});
		});
	};

	// websnap functions
	$.fn.websnap.initialize = function(){
		$('#websnap').remove();
		var websnapContainer = '<div id="websnap"><img id="websnap-shot" /><p style="text-align:center;">WebSnapshot</p></div>';
		var string = websnapContainer;
		$("body").append(string);
		$('#websnap').css({position: 'absolute', width: '0px', border: '1px solid #333', backgroundColor: '#fff'}).hide();
	
	};

	

	$.fn.websnap.start = function(imageLink, position){
		
		$.fn.websnap.doChangeImage(imageLink.href);
		$('#websnap').css({top: position[1]+'px', left:position[0]+'px'})

	};

	
	$.fn.websnap.end = function() {	
		$('#websnap').hide();
	};
	
	$.fn.websnap.doChangeImage = function(href) {
		imgPreloader = new Image();
		
		snapUrl = $.fn.websnap.opts.url+'?url='+Base64.encode(href);
		// once image is preloaded, resize image container
		imgPreloader.onload=function() {
		    var newWidth = imgPreloader.width;
		    var newHeight = imgPreloader.height;

			$('#websnap-shot').attr('src', snapUrl)
							   .width(newWidth).height(newHeight);
			$('#websnap').css({width: newWidth+'px'}).show();
		}

		imgPreloader.src = snapUrl;
	}
	$.fn.websnap.defaults = {
		fileLoadingImage : 'images/loading.gif'
	};
})(jQuery);

/**
*
*  Base64 encode / decode
*  http://www.webtoolkit.info/
*
**/
 
var Base64 = {
 
	// private property
	_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
 
	// public method for encoding
	encode : function (input) {
		var output = "";
		var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
		var i = 0;
 
		input = Base64._utf8_encode(input);
 
		while (i < input.length) {
 
			chr1 = input.charCodeAt(i++);
			chr2 = input.charCodeAt(i++);
			chr3 = input.charCodeAt(i++);
 
			enc1 = chr1 >> 2;
			enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
			enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
			enc4 = chr3 & 63;
 
			if (isNaN(chr2)) {
				enc3 = enc4 = 64;
			} else if (isNaN(chr3)) {
				enc4 = 64;
			}
 
			output = output +
			this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
			this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
 
		}
 
		return output;
	},
 
	// public method for decoding
	decode : function (input) {
		var output = "";
		var chr1, chr2, chr3;
		var enc1, enc2, enc3, enc4;
		var i = 0;
 
		input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
 
		while (i < input.length) {
 
			enc1 = this._keyStr.indexOf(input.charAt(i++));
			enc2 = this._keyStr.indexOf(input.charAt(i++));
			enc3 = this._keyStr.indexOf(input.charAt(i++));
			enc4 = this._keyStr.indexOf(input.charAt(i++));
 
			chr1 = (enc1 << 2) | (enc2 >> 4);
			chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
			chr3 = ((enc3 & 3) << 6) | enc4;
 
			output = output + String.fromCharCode(chr1);
 
			if (enc3 != 64) {
				output = output + String.fromCharCode(chr2);
			}
			if (enc4 != 64) {
				output = output + String.fromCharCode(chr3);
			}
 
		}
 
		output = Base64._utf8_decode(output);
 
		return output;
 
	},
 
	// private method for UTF-8 encoding
	_utf8_encode : function (string) {
		string = string.replace(/\r\n/g,"\n");
		var utftext = "";
 
		for (var n = 0; n < string.length; n++) {
 
			var c = string.charCodeAt(n);
 
			if (c < 128) {
				utftext += String.fromCharCode(c);
			}
			else if((c > 127) && (c < 2048)) {
				utftext += String.fromCharCode((c >> 6) | 192);
				utftext += String.fromCharCode((c & 63) | 128);
			}
			else {
				utftext += String.fromCharCode((c >> 12) | 224);
				utftext += String.fromCharCode(((c >> 6) & 63) | 128);
				utftext += String.fromCharCode((c & 63) | 128);
			}
 
		}
 
		return utftext;
	},
 
	// private method for UTF-8 decoding
	_utf8_decode : function (utftext) {
		var string = "";
		var i = 0;
		var c = c1 = c2 = 0;
 
		while ( i < utftext.length ) {
 
			c = utftext.charCodeAt(i);
 
			if (c < 128) {
				string += String.fromCharCode(c);
				i++;
			}
			else if((c > 191) && (c < 224)) {
				c2 = utftext.charCodeAt(i+1);
				string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
				i += 2;
			}
			else {
				c2 = utftext.charCodeAt(i+1);
				c3 = utftext.charCodeAt(i+2);
				string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
				i += 3;
			}
 
		}
 
		return string;
	}
 
}