var jsc = now(),
	rscript = /<script(.|\s)*?\/script>/g,
	rselectTextarea = /select|textarea/i,
	rinput = /text|hidden|password|search/i,
	jsre = /=\?(&|$)/,
	rquery = /\?/,
	rts = /(\?|&)_=.*?(&|$)/,
	rurl = /^(\w+:)?\/\/([^\/?#]+)/,
	r20 = /%20/g;

jQuery.fn.extend({
	// Keep a copy of the old load
	_load: jQuery.fn.load,

	load: function( url, params, callback ) {
		if ( typeof url !== "string" ) {
			return this._load( url );

		// Don't do a request if no elements are being requested
		} else if ( !this.length ) {
			return this;
		}

		var off = url.indexOf(" ");
		if ( off >= 0 ) {
			var selector = url.slice(off, url.length);
			url = url.slice(0, off);
		}

		// Default to a GET request
		var type = "GET";

		// If the second parameter was provided
		if ( params ) {
			// If it's a function
			if ( jQuery.isFunction( params ) ) {
				// We assume that it's the callback
				callback = params;
				params = null;

			// Otherwise, build a param string
			} else if ( typeof params === "object" ) {
				params = jQuery.param( params );
				type = "POST";
			}
		}

		// Request the remote document
		jQuery.ajax({
			url: url,
			type: type,
			dataType: "html",
			data: params,
			context:this,
			complete: function(res, status){
				// If successful, inject the HTML into all the matched elements
				if ( status === "success" || status === "notmodified" ) {
					// See if a selector was specified
					this.html( selector ?
						// Create a dummy div to hold the results
						jQuery("<div />")
							// inject the contents of the document in, removing the scripts
							// to avoid any 'Permission Denied' errors in IE
							.append(res.responseText.replace(rscript, ""))

							// Locate the specified elements
							.find(selector) :

						// If not, just inject the full result
						res.responseText );
				}

				if ( callback ) {
					this.each( callback, [res.responseText, status, res] );
				}
			}
		});

		return this;
	},

	serialize: function() {
		return jQuery.param(this.serializeArray());
	},
	serializeArray: function() {
		return this.map(function(){
			return this.elements ? jQuery.makeArray(this.elements) : this;
		})
		.filter(function(){
			return this.name && !this.disabled &&
				(this.checked || rselectTextarea.test(this.nodeName) ||
					rinput.test(this.type));
		})
		.map(function(i, elem){
			var val = jQuery(this).val();

			return val == null ?
				null :
				jQuery.isArray(val) ?
					jQuery.map( val, function(val, i){
						return {name: elem.name, value: val};
					}) :
					{name: elem.name, value: val};
		}).get();
	}
});

// Attach a bunch of functions for handling common AJAX events
jQuery.each( "ajaxStart ajaxStop ajaxComplete ajaxError ajaxSuccess ajaxSend".split(" "), function(i,o){
	jQuery.fn[o] = function(f){
		return this.bind(o, f);
	};
});

jQuery.extend({

	get: function( url, data, callback, type ) {
		// shift arguments if data argument was omited
		if ( jQuery.isFunction( data ) ) {
			type = type || callback;
			callback = data;
			data = null;
		}

		return jQuery.ajax({
			type: "GET",
			url: url,
			data: data,
			success: callback,
			dataType: type
		});
	},

	getScript: function( url, callback ) {
		return jQuery.get(url, null, callback, "script");
	},

	getJSON: function( url, data, callback ) {
		return jQuery.get(url, data, callback, "json");
	},

	post: function( url, data, callback, type ) {
		// shift arguments if data argument was omited
		if ( jQuery.isFunction( data ) ) {
			type = type || callback;
			callback = data;
			data = {};
		}

		return jQuery.ajax({
			type: "POST",
			url: url,
			data: data,
			success: callback,
			dataType: type
		});
	},

	ajaxSetup: function( settings ) {
		jQuery.extend( jQuery.ajaxSettings, settings );
	},

	ajaxSettings: {
		url: location.href,
		global: true,
		type: "GET",
		contentType: "application/x-www-form-urlencoded",
		processData: true,
		async: true,
		/*
		timeout: 0,
		data: null,
		username: null,
		password: null,
		*/
		// Create the request object; Microsoft failed to properly
		// implement the XMLHttpRequest in IE7, so we use the ActiveXObject when it is available
		// This function can be overriden by calling jQuery.ajaxSetup
		xhr: function(){
			return window.ActiveXObject ?
				new ActiveXObject("Microsoft.XMLHTTP") :
				new XMLHttpRequest();
		},
		accepts: {
			xml: "application/xml, text/xml",
			html: "text/html",
			script: "text/javascript, application/javascript",
			json: "application/json, text/javascript",
			text: "text/plain",
			_default: "*/*"
		}
	},

	// Last-Modified header cache for next request
	lastModified: {},
	etag: {},

	ajax: function( origSettings ) {
		var s = jQuery.extend(true, {}, jQuery.ajaxSettings, origSettings);
		
		var jsonp, status, data,
			callbackContext = s.context || window,
			type = s.type.toUpperCase();

		// convert data if not already a string
		if ( s.data && s.processData && typeof s.data !== "string" ) {
			s.data = jQuery.param(s.data);
		}

		// Handle JSONP Parameter Callbacks
		if ( s.dataType === "jsonp" ) {
			if ( type === "GET" ) {
				if ( !jsre.test( s.url ) ) {
					s.url += (rquery.test( s.url ) ? "&" : "?") + (s.jsonp || "callback") + "=?";
				}
			} else if ( !s.data || !jsre.test(s.data) ) {
				s.data = (s.data ? s.data + "&" : "") + (s.jsonp || "callback") + "=?";
			}
			s.dataType = "json";
		}

		// Build temporary JSONP function
		if ( s.dataType === "json" && (s.data && jsre.test(s.data) || jsre.test(s.url)) ) {
			jsonp = s.jsonpCallback || ("jsonp" + jsc++);

			// Replace the =? sequence both in the query string and the data
			if ( s.data ) {
				s.data = (s.data + "").replace(jsre, "=" + jsonp + "$1");
			}

			s.url = s.url.replace(jsre, "=" + jsonp + "$1");

			// We need to make sure
			// that a JSONP style response is executed properly
			s.dataType = "script";

			// Handle JSONP-style loading
			window[ jsonp ] = window[ jsonp ] || function(tmp){
				data = tmp;
				success();
				complete();
				// Garbage collect
				window[ jsonp ] = undefined;
				try{ delete window[ jsonp ]; } catch(e){}
				if ( head ) {
					head.removeChild( script );
				}
			};
		}

		if ( s.dataType === "script" && s.cache === null ) {
			s.cache = false;
		}

		if ( s.cache === false && type === "GET" ) {
			var ts = now();

			// try replacing _= if it is there
			var ret = s.url.replace(rts, "$1_=" + ts + "$2");

			// if nothing was replaced, add timestamp to the end
			s.url = ret + ((ret === s.url) ? (rquery.test(s.url) ? "&" : "?") + "_=" + ts : "");
		}

		// If data is available, append data to url for get requests
		if ( s.data && type === "GET" ) {
			s.url += (rquery.test(s.url) ? "&" : "?") + s.data;
		}

		// Watch for a new set of requests
		if ( s.global && ! jQuery.active++ ) {
			jQuery.event.trigger( "ajaxStart" );
		}

		// Matches an absolute URL, and saves the domain
		var parts = rurl.exec( s.url ),
			remote = parts && (parts[1] && parts[1] !== location.protocol || parts[2] !== location.host);

		// If we're requesting a remote document
		// and trying to load JSON or Script with a GET
		if ( s.dataType === "script" && type === "GET" && remote ) {
			var head = document.getElementsByTagName("head")[0] || document.documentElement;
			var script = document.createElement("script");
			script.src = s.url;
			if ( s.scriptCharset ) {
				script.charset = s.scriptCharset;
			}

			// Handle Script loading
			if ( !jsonp ) {
				var done = false;

				// Attach handlers for all browsers
				script.onload = script.onreadystatechange = function(){
					if ( !done && (!this.readyState ||
							this.readyState === "loaded" || this.readyState === "complete") ) {
						done = true;
						success();
						complete();

						// Handle memory leak in IE
						script.onload = script.onreadystatechange = null;
						if ( head && script.parentNode ) {
							head.removeChild( script );
						}
					}
				};
			}

			// Use insertBefore instead of appendChild  to circumvent an IE6 bug.
			// This arises when a base node is used (#2709 and #4378).
			head.insertBefore( script, head.firstChild );

			// We handle everything using the script element injection
			return undefined;
		}

		var requestDone = false;

		// Create the request object
		var xhr = s.xhr();

		// Open the socket
		// Passing null username, generates a login popup on Opera (#2865)
		if ( s.username ) {
			xhr.open(type, s.url, s.async, s.username, s.password);
		} else {
			xhr.open(type, s.url, s.async);
		}

		// Need an extra try/catch for cross domain requests in Firefox 3
		try {
			// Set the correct header, if data is being sent
			if ( s.data || origSettings && origSettings.contentType ) {
				xhr.setRequestHeader("Content-Type", s.contentType);
			}

			// Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
			if ( s.ifModified ) {
				if ( jQuery.lastModified[s.url] ) {
					xhr.setRequestHeader("If-Modified-Since", jQuery.lastModified[s.url]);
				}

				if ( jQuery.etag[s.url] ) {
					xhr.setRequestHeader("If-None-Match", jQuery.etag[s.url]);
				}
			}

			// Set header so the called script knows that it's an XMLHttpRequest
			// Only send the header if it's not a remote XHR
			if ( !remote ) {
				xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
			}

			// Set the Accepts header for the server, depending on the dataType
			xhr.setRequestHeader("Accept", s.dataType && s.accepts[ s.dataType ] ?
				s.accepts[ s.dataType ] + ", */*" :
				s.accepts._default );
		} catch(e){}

		// Allow custom headers/mimetypes and early abort
		if ( s.beforeSend && s.beforeSend.call(callbackContext, xhr, s) === false ) {
			// Handle the global AJAX counter
			if ( s.global && ! --jQuery.active ) {
				jQuery.event.trigger( "ajaxStop" );
			}

			// close opended socket
			xhr.abort();
			return false;
		}

		if ( s.global ) {
			trigger("ajaxSend", [xhr, s]);
		}

		// Wait for a response to come back
		var onreadystatechange = function(isTimeout){
			// The request was aborted, clear the interval and decrement jQuery.active
			if ( !xhr || xhr.readyState === 0 ) {
				if ( ival ) {
					// clear poll interval
					clearInterval( ival );
					ival = null;

					// Handle the global AJAX counter
					if ( s.global && ! --jQuery.active ) {
						jQuery.event.trigger( "ajaxStop" );
					}
				}

			// The transfer is complete and the data is available, or the request timed out
			} else if ( !requestDone && xhr && (xhr.readyState === 4 || isTimeout === "timeout") ) {
				requestDone = true;

				// clear poll interval
				if (ival) {
					clearInterval(ival);
					ival = null;
				}

				status = isTimeout === "timeout" ?
					"timeout" :
					!jQuery.httpSuccess( xhr ) ?
						"error" :
						s.ifModified && jQuery.httpNotModified( xhr, s.url ) ?
							"notmodified" :
							"success";

				if ( status === "success" ) {
					// Watch for, and catch, XML document parse errors
					try {
						// process the data (runs the xml through httpData regardless of callback)
						data = jQuery.httpData( xhr, s.dataType, s );
					} catch(e) {
						status = "parsererror";
					}
				}

				// Make sure that the request was successful or notmodified
				if ( status === "success" || status === "notmodified" ) {
					// JSONP handles its own success callback
					if ( !jsonp ) {
						success();
					}
				} else {
					jQuery.handleError(s, xhr, status);
				}

				// Fire the complete handlers
				complete();

				if ( isTimeout === "timeout" ) {
					xhr.abort();
				}

				// Stop memory leaks
				if ( s.async ) {
					xhr = null;
				}
			}
		};

		if ( s.async ) {
			// don't attach the handler to the request, just poll it instead
			var ival = setInterval(onreadystatechange, 13);

			// Timeout checker
			if ( s.timeout > 0 ) {
				setTimeout(function(){
					// Check to see if the request is still happening
					if ( xhr && !requestDone ) {
						onreadystatechange( "timeout" );
					}
				}, s.timeout);
			}
		}

		// Send the data
		try {
			xhr.send( type === "POST" || type === "PUT" ? s.data : null );
		} catch(e) {
			jQuery.handleError(s, xhr, null, e);
			// Fire the complete handlers
			complete();
		}

		// firefox 1.5 doesn't fire statechange for sync requests
		if ( !s.async ) {
			onreadystatechange();
		}

		function success(){
			// If a local callback was specified, fire it and pass it the data
			if ( s.success ) {
				s.success.call( callbackContext, data, status, xhr );
			}

			// Fire the global callback
			if ( s.global ) {
				trigger( "ajaxSuccess", [xhr, s] );
			}
		}

		function complete(){
			// Process result
			if ( s.complete ) {
				s.complete.call( callbackContext, xhr, status);
			}

			// The request was completed
			if ( s.global ) {
				trigger( "ajaxComplete", [xhr, s] );
			}

			// Handle the global AJAX counter
			if ( s.global && ! --jQuery.active ) {
				jQuery.event.trigger( "ajaxStop" );
			}
		}
		
		function trigger(type, args){
			(s.context ? jQuery(s.context) : jQuery.event).trigger(type, args);
		}

		// return XMLHttpRequest to allow aborting the request etc.
		return xhr;
	},

	handleError: function( s, xhr, status, e ) {
		// If a local callback was specified, fire it
		if ( s.error ) {
			s.error.call( s.context || window, xhr, status, e );
		}

		// Fire the global callback
		if ( s.global ) {
			(s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );
		}
	},

	// Counter for holding the number of active queries
	active: 0,

	// Determines if an XMLHttpRequest was successful or not
	httpSuccess: function( xhr ) {
		try {
			// IE error sometimes returns 1223 when it should be 204 so treat it as success, see #1450
			return !xhr.status && location.protocol === "file:" ||
				// Opera returns 0 when status is 304
				( xhr.status >= 200 && xhr.status < 300 ) ||
				xhr.status === 304 || xhr.status === 1223 || xhr.status === 0;
		} catch(e){}

		return false;
	},

	// Determines if an XMLHttpRequest returns NotModified
	httpNotModified: function( xhr, url ) {
		var lastModified = xhr.getResponseHeader("Last-Modified"),
			etag = xhr.getResponseHeader("Etag");

		if ( lastModified ) {
			jQuery.lastModified[url] = lastModified;
		}

		if ( etag ) {
			jQuery.etag[url] = etag;
		}

		// Opera returns 0 when status is 304
		return xhr.status === 304 || xhr.status === 0;
	},

	httpData: function( xhr, type, s ) {
		var ct = xhr.getResponseHeader("content-type"),
			xml = type === "xml" || !type && ct && ct.indexOf("xml") >= 0,
			data = xml ? xhr.responseXML : xhr.responseText;

		if ( xml && data.documentElement.nodeName === "parsererror" ) {
			throw "parsererror";
		}

		// Allow a pre-filtering function to sanitize the response
		// s is checked to keep backwards compatibility
		if ( s && s.dataFilter ) {
			data = s.dataFilter( data, type );
		}

		// The filter can actually parse the response
		if ( typeof data === "string" ) {

			// If the type is "script", eval it in global context
			if ( type === "script" ) {
				jQuery.globalEval( data );
			}

			// Get the JavaScript object, if JSON is used.
			if ( type === "json" ) {
				if ( typeof JSON === "object" && JSON.parse ) {
					data = JSON.parse( data );
				} else {
					data = (new Function("return " + data))();
				}
			}
		}

		return data;
	},

	// Serialize an array of form elements or a set of
	// key/values into a query string
	param: function( a ) {
		var s = [],
			param_traditional = jQuery.param.traditional;
		
		function add( key, value ){
			// If value is a function, invoke it and return its value
			value = jQuery.isFunction(value) ? value() : value;
			s[ s.length ] = encodeURIComponent(key) + '=' + encodeURIComponent(value);
		}
		
		// If an array was passed in, assume that it is an array
		// of form elements
		if ( jQuery.isArray(a) || a.jquery ) {
			// Serialize the form elements
			jQuery.each( a, function() {
				add( this.name, this.value );
			});
			
		} else {
			// Encode parameters from object, recursively. If
			// jQuery.param.traditional is set, encode the "old" way
			// (the way 1.3.2 or older did it)
			jQuery.each( a, function buildParams( prefix, obj ) {
				
				if ( jQuery.isArray(obj) ) {
					jQuery.each( obj, function(i,v){
						// Due to rails' limited request param syntax, numeric array
						// indices are not supported. To avoid serialization ambiguity
						// issues, serialized arrays can only contain scalar values. php
						// does not have this issue, but we should go with the lowest
						// common denominator
						add( prefix + ( param_traditional ? "" : "[]" ), v );
					});
					
				} else if ( typeof obj == "object" ) {
					if ( param_traditional ) {
						add( prefix, obj );
						
					} else {
						jQuery.each( obj, function(k,v){
							buildParams( prefix ? prefix + "[" + k + "]" : k, v );
						});
					}
				} else {
					add( prefix, obj );
				}
			});
		}
		// Return the resulting serialization
		return s.join("&").replace(r20, "+");
	}

});