/*
AJFORM 1.1 - World's Easiest JavaScript AJAX ToolKit 
ajform.js
http://redredmusic.com/brendon/ajform/
Brendon Crawford <brendy@gmail.com>

	** BSD LICENSE *********************************************************
	
	Copyright (c) 2005 Brendon Crawford
	All rights reserved.
	
	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions
	are met:
	1. Redistributions of source code must retain the above copyright
	   notice, this list of conditions and the following disclaimer.
	2. Redistributions in binary form must reproduce the above copyright
	   notice, this list of conditions and the following disclaimer in the
	   documentation and/or other materials provided with the distribution.
	3. The name of the author may not be used to endorse or promote products
	   derived from this software without specific prior written permission.
	
	THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	************************************************************************

*/

		DOM = new Object;
			DOM.setEventListener = function( eventName , functionName ) {
				if( document.addEventListener ) {
				 this.addEventListener( eventName , functionName , false );
				}
				else if( document.attachEvent ) {
				 this.attachEvent( "on" + eventName , functionName );								
				}
			}
			DOM.getSourceElement = function() {
				if( window.event != undefined ) {
				 return window.event.srcElement;
				}
				else {
				 return this;
				}
			}
		window.setEventListener = DOM.setEventListener;


		AJForm = new Object;
			AJForm.STATUS = {
				'SUCCESS' : 0 ,
				'HTTP_OBJECT_FAILED' : 1 ,
				'FILE_UPLOAD_FAILED' : 2 ,
				'SERVER_ERROR' : 3
			};
			AJForm.getHTTPRequest = function() {
				if( typeof window.ActiveXObject != 'undefined' ) {
					try {
					 doc = new ActiveXObject("Microsoft.XMLHTTP");
					}
					catch(e) {
					 return false;
					}
				}
				else if( typeof XMLHttpRequest != 'undefined' ) {
					try {
					 doc = new XMLHttpRequest();
					}
					catch(e) {
					 return false;
					}
				}
			 return doc;
			}

			AJForm.activateForm = function() {
			 this.getSourceElement = DOM.getSourceElement;
			 thisForm = this.getSourceElement();
			 activeRetVal = AJForm.submitForm( thisForm );
			 return activeRetVal;
			}
			
			/*
				FORM SUBMISSION:
					submitForm()
				SCRIPTED SUBMISSION:
					submitForm( [formObject [, callbackFunction]] )
			*/
			AJForm.submitForm = function( thisElm ){
				//if a second argument was specified
				if( AJForm.submitForm.arguments.length > 1 ) {
				 userFuncName =  AJForm.submitForm.arguments[1];
				}
				else {
				 userFuncName = thisElm.getAttribute( 'ajform-callback' );
				}
				if( userFuncName == null ) {
				 return true;
				}
			 //userFunc is the callback reference
			 userFunc = eval(userFuncName);
			 debugIt = thisElm.getAttribute('ajform-debug');
			 	if( debugIt != null ) {
					if( debugIt == "1" ||
						debugIt.toLowerCase() == "true" ||
						debugIt.toLowerCase() == "yes" ) {
					 debugIt = true;
					}
			 	}
				else {
				 debugIt = false;
				}
				//no action specified
			 	if( (file = thisElm.getAttribute('action')) == null ) {
			 	 file = new String( window.location );
			 	}
			 	//intiialize httpRequest object and see if it failed
				if( !(doc = AJForm.getHTTPRequest()) ||
					!(docLoader = AJForm.getHTTPRequest()) ) {
					if( debugIt ) {
					 alert( "Error: Could not initiate HTTPRequest." );
					}
				 userFuncVal = userFunc( null , AJForm.STATUS['HTTP_OBJECT_FAILED'] );
				 return userFuncVal;
				}
			 dataStr = "";
				//construct values
				for( var e = 0; e < thisElm.elements.length; e++ ) {
					//we canot yet handle
					if( thisElm.elements[e].name == '' || thisElm.elements[e].name == 'undefined' ) {
					 continue;
					}
					//file upload
					if( (thisElmType = thisElm.elements[e].getAttribute('type')) != null ) {
						if( thisElmType.toLowerCase() == "file" ) {
						 //if we encounter a file upload, then bail out
							if( debugIt ) {
							 alert( "Error: Cannot handle file uploads." );
							}
						 userFuncVal = userFunc( null , AJForm.STATUS['FILE_UPLOAD_FAILED'] );
						 return userFuncVal;
						}
					}
					if( e ) {
					 dataStr += "&";
					}
				 dataStr += thisElm.elements[e].name + "=" + escape(thisElm.elements[e].value);
				}
				//identify this as being an ajform set
				dataStr += "&ajform:submit=1";
				doc.onreadystatechange = function() {
					// only if req shows "loaded"
					if (doc.readyState == 4) {
						// only if "OK"
						if (doc.status == 200) {
						 userFunc( doc.responseText , AJForm.STATUS['SUCCESS'] );
						}
						else {
							if( debugIt ) {
							 alert("Error: " + doc.statusText);
							}
						 userFunc( doc.responseText , AJForm.STATUS['SERVER_ERROR'] );						 
						}
					}
				}
			  requestType = thisElm.getAttribute('method');
			  requestType = ( requestType == null || requestType == 'undefined' ) ? 'get' : requestType;
			  	//METHOD
			 	if( requestType.toLowerCase() == "get" ) {
			 	 file += (file.match(/\?/)) ? ("&" + dataStr) : ("?" + dataStr);
				 doc.open( "GET", file, true );
				 doc.setRequestHeader( "Content-Type" , "application/x-www-form-urlencoded; charset=UTF-8" );
				 doc.send('');
			 	}
			 	else if( requestType.toLowerCase() == "post" ) {
				 doc.open( "POST", file, true );
				 doc.setRequestHeader( "Content-Type" , "application/x-www-form-urlencoded; charset=UTF-8" );
				 doc.send(dataStr);
			 	}
			  return false;
			}
			
			AJForm.init = function() {
				for( var i = 0; i < document.forms.length; i++ ) {
				 document.forms[i].onsubmit = AJForm.activateForm;
				}
			}

			//SET THE LISTENER TO INITIALIZE THE ACTIONS
			window.setEventListener( 'load' , AJForm.init );