Image Upload Feature

Adding image upload to the markdown editor using
jQuery.AjaxFileUpload.js.

system/admin/editor/js/jquery.ajaxfileupload.js

@@ -0,0 +1,164 @@
+/*
+// jQuery Ajax File Uploader
+//
+// @author: Jordan Feldstein <jfeldstein.com>
+//
+//  - Ajaxifies an individual <input type="file">
+//  - Files are sandboxed. Doesn't matter how many, or where they are, on the page.
+//  - Allows for extra parameters to be included with the file
+//  - onStart callback can cancel the upload by returning false
+*/
+
+
+(function($) {
+    $.fn.ajaxfileupload = function(options) {
+        var settings = {
+          params: {},
+          action: '',
+          onStart: function() { },
+          onComplete: function(response) { },
+          onCancel: function() { },
+          validate_extensions : true,
+          valid_extensions : ['gif','png','jpg','jpeg'],
+          submit_button : null
+        };
+
+        var uploading_file = false;
+
+        if ( options ) { 
+          $.extend( settings, options );
+        }
+
+
+        // 'this' is a jQuery collection of one or more (hopefully) 
+        //  file elements, but doesn't check for this yet
+        return this.each(function() {
+          var $element = $(this);
+
+          // Skip elements that are already setup. May replace this 
+          //  with uninit() later, to allow updating that settings
+          if($element.data('ajaxUploader-setup') === true) return;
+
+          $element.change(function()
+          {
+            // since a new image was selected, reset the marker
+            uploading_file = false;
+
+            // only update the file from here if we haven't assigned a submit button
+            if (settings.submit_button == null)
+            {
+              upload_file();
+            }
+          });
+
+          if (settings.submit_button == null)
+          {
+            // do nothing
+          } else
+          {
+            settings.submit_button.click(function(e)
+            {
+              // Prevent non-AJAXy submit
+              e.preventDefault();
+              
+              // only attempt to upload file if we're not uploading
+              if (!uploading_file)
+              {
+                upload_file();
+              }
+            });
+          }
+
+          var upload_file = function()
+          {
+            if($element.val() == '') return settings.onCancel.apply($element, [settings.params]);
+
+            // make sure extension is valid
+            var ext = $element.val().split('.').pop().toLowerCase();
+            if(true === settings.validate_extensions && $.inArray(ext, settings.valid_extensions) == -1)
+            {
+              // Pass back to the user
+              settings.onComplete.apply($element, [{status: false, message: 'The select file type is invalid. File must be ' + settings.valid_extensions.join(', ') + '.'}, settings.params]);
+            } else
+            { 
+              uploading_file = true;
+
+              // Creates the form, extra inputs and iframe used to 
+              //  submit / upload the file
+              wrapElement($element);
+
+              // Call user-supplied (or default) onStart(), setting
+              //  it's this context to the file DOM element
+              var ret = settings.onStart.apply($element, [settings.params]);
+
+              // let onStart have the option to cancel the upload
+              if(ret !== false)
+              {
+                $element.parent('form').submit(function(e) { e.stopPropagation(); }).submit();
+              }
+            }
+          };
+
+          // Mark this element as setup
+          $element.data('ajaxUploader-setup', true);
+
+          /*
+          // Internal handler that tries to parse the response 
+          //  and clean up after ourselves. 
+          */
+          var handleResponse = function(loadedFrame, element) {
+            var response, responseStr = $(loadedFrame).contents().text();
+            try {
+              //response = $.parseJSON($.trim(responseStr));
+              response = JSON.parse(responseStr);
+            } catch(e) {
+              response = responseStr;
+            }
+
+            // Tear-down the wrapper form
+            element.siblings().remove();
+            element.unwrap();
+
+            uploading_file = false;
+
+            // Pass back to the user
+            settings.onComplete.apply(element, [response, settings.params]);
+          };
+
+          /*
+          // Wraps element in a <form> tag, and inserts hidden inputs for each
+          //  key:value pair in settings.params so they can be sent along with
+          //  the upload. Then, creates an iframe that the whole thing is 
+          //  uploaded through. 
+          */
+          var wrapElement = function(element) {
+            // Create an iframe to submit through, using a semi-unique ID
+            var frame_id = 'ajaxUploader-iframe-' + Math.round(new Date().getTime() / 1000)
+            $('body').after('<iframe width="0" height="0" style="display:none;" name="'+frame_id+'" id="'+frame_id+'"/>');
+            $('#'+frame_id).get(0).onload = function() {
+              handleResponse(this, element);
+            };
+
+            // Wrap it in a form
+            element.wrap(function() {
+              return '<form action="' + settings.action + '" method="POST" enctype="multipart/form-data" target="'+frame_id+'" />'
+            })
+            // Insert <input type='hidden'>'s for each param
+            .before(function() {
+              var key, html = '';
+              for(key in settings.params) {
+                var paramVal = settings.params[key];
+                if (typeof paramVal === 'function') {
+                  paramVal = paramVal();
+                }
+                html += '<input type="hidden" name="' + key + '" value="' + paramVal + '" />';
+              }
+              return html;
+            });
+          }
+
+
+
+        });
+      }
+})( jQuery )