Implemented Text Editor widget that integrates all operations on

textareas including HTML editor and spellchecking

1 files changed, 550 insertions, 212 deletions

diff --git a/program/js/editor.js b/program/js/editor.js
index 280eb2ae1..6540bd56a 100644
--- a/program/js/editor.js
+++ b/program/js/editor.js
@@ -26,13 +26,18 @@
  * for the JavaScript code in this file.
  *
  * @author Eric Stadtherr <estadtherr@gmail.com>
+ * @author Aleksander Machniak <alec@alec.pl>
  */
 
-// Initialize HTML editor
-function rcmail_editor_init(config)
+/**
+ * Roundcube Text Editor Widget class
+ * @constructor
+ */
+function rcube_text_editor(config, id)
 {
-  var ret, conf = {
-      selector: '.mce_editor',
+  var ref = this,
+    conf = {
+      selector: '#' + ($('#' + id).is('.mce_editor') ? id : 'fake-editor-id'),
       theme: 'modern',
       language: config.lang,
       content_css: config.skin_path + '/editor_content.css?v2',
@@ -48,14 +53,26 @@ function rcmail_editor_init(config)
       paste_data_images: true
     };
 
-  if (config.mode == 'identity')
+  // register spellchecker for plain text editor
+  this.spellcheck_observer = function() {};
+  if (config.spellchecker) {
+    this.spellchecker = config.spellchecker;
+    if (config.spellcheck_observer) {
+      this.spellchecker.spelling_state_observer = this.spellcheck_observer = config.spellcheck_observer;
+    }
+  }
+
+  // minimal editor
+  if (config.mode == 'identity') {
     $.extend(conf, {
       plugins: ['autolink charmap code hr link paste tabfocus textcolor'],
       toolbar: 'bold italic underline alignleft aligncenter alignright alignjustify'
         + ' | outdent indent charmap hr link unlink code forecolor'
         + ' | fontselect fontsizeselect'
     });
-  else { // mail compose
+  }
+  // full-featured editor
+  else {
     $.extend(conf, {
       plugins: ['autolink charmap code directionality emoticons link image media nonbreaking'
         + ' paste table tabfocus textcolor searchreplace' + (config.spellcheck ? ' spellchecker' : '')],
@@ -65,251 +82,572 @@ function rcmail_editor_init(config)
       spellchecker_rpc_url: '../../../../../?_task=utils&_action=spell_html&_remote=1',
       spellchecker_language: rcmail.env.spell_lang,
       accessibility_focus: false,
-      file_browser_callback: rcmail_file_browser_callback,
+      file_browser_callback: function(name, url, type, win) { ref.file_browser_callback(name, url, type); },
       // @todo: support more than image (types: file, image, media)
       file_browser_callback_types: 'image'
     });
-
-    conf.setup = function(ed) {
-      ed.on('init', rcmail_editor_callback);
-      // add handler for spellcheck button state update
-      ed.on('SpellcheckStart SpellcheckEnd', function(args) {
-        rcmail.env.spellcheck_active = args.type == 'spellcheckstart';
-        rcmail.spellcheck_state();
-      });
-      ed.on('keypress', function() {
-        rcmail.compose_type_activity++;
-      });
-    }
   }
 
   // support external configuration settings e.g. from skin
   if (window.rcmail_editor_settings)
     $.extend(conf, window.rcmail_editor_settings);
 
+  conf.setup = function(ed) {
+    ed.on('init', function(ed) { ref.init_callback(ed); });
+    // add handler for spellcheck button state update
+    ed.on('SpellcheckStart SpellcheckEnd', function(args) {
+      ref.spellcheck_active = args.type == 'spellcheckstart';
+      ref.spellcheck_observer();
+    });
+    ed.on('keypress', function() {
+      rcmail.compose_type_activity++;
+    });
+  };
+
+  // textarea identifier
+  this.id = id;
+  // reference to active editor (if in HTML mode)
+  this.editor = null;
+
   tinymce.init(conf);
-}
 
-// react to real individual tinyMCE editor init
-function rcmail_editor_callback()
-{
-  var css = {},
-    elem = rcube_find_object('_from'),
-    fe = rcmail.env.compose_focus_elem;
+  // react to real individual tinyMCE editor init
+  this.init_callback = function(event)
+  {
+    this.editor = event.target;
+
+    if (rcmail.env.action != 'compose') {
+      return;
+    }
 
-  if (rcmail.env.default_font)
-    css['font-family'] = rcmail.env.default_font;
+    var css = {},
+      elem = rcube_find_object('_from'),
+      fe = rcmail.env.compose_focus_elem;
 
-  if (rcmail.env.default_font_size)
-    css['font-size'] = rcmail.env.default_font_size;
+    if (rcmail.env.default_font)
+      css['font-family'] = rcmail.env.default_font;
 
-  if (css['font-family'] || css['font-size'])
-    $(tinymce.get(rcmail.env.composebody).getBody()).css(css);
+    if (rcmail.env.default_font_size)
+      css['font-size'] = rcmail.env.default_font_size;
 
-  if (elem && elem.type == 'select-one') {
-    // insert signature (only for the first time)
-    if (!rcmail.env.identities_initialized)
-      rcmail.change_identity(elem);
+    if (css['font-family'] || css['font-size'])
+      $(this.editor.getBody()).css(css);
 
-    // Focus previously focused element
-    if (fe && fe.id != rcmail.env.composebody) {
-      // use setTimeout() for IE9 (#1488541)
-      window.setTimeout(function() {
-        window.focus(); // for WebKit (#1486674)
-        fe.focus();
-      }, 10);
+    if (elem && elem.type == 'select-one') {
+      // insert signature (only for the first time)
+      if (!rcmail.env.identities_initialized)
+        rcmail.change_identity(elem);
+
+      // Focus previously focused element
+      if (fe && fe.id != this.id) {
+        // use setTimeout() for IE9 (#1488541)
+        window.setTimeout(function() {
+          window.focus(); // for WebKit (#1486674)
+          fe.focus();
+        }, 10);
+      }
     }
-  }
 
-  // set tabIndex and set focus to element that was focused before
-  rcmail_editor_tabindex(fe && fe.id == rcmail.env.composebody);
-  // Trigger resize (needed for proper editor resizing in some browsers)
-  window.setTimeout(function() { $(window).resize(); }, 100);
-}
+    // set tabIndex and set focus to element that was focused before
+    this.tabindex(fe && fe.id == this.id);
+    // Trigger resize (needed for proper editor resizing in some browsers)
+    window.setTimeout(function() { $(window).resize(); }, 100);
+  };
 
-// set tabIndex on tinymce editor
-function rcmail_editor_tabindex(focus)
-{
-  if (rcmail.env.task == 'mail') {
-    var editor = tinymce.get(rcmail.env.composebody);
-    if (editor) {
-      var textarea = editor.getElement(),
-        node = editor.getContentAreaContainer().childNodes[0];
+  // set tabIndex on tinymce editor
+  this.tabindex = function(focus)
+  {
+    if (rcmail.env.task == 'mail' && this.editor) {
+      var textarea = this.editor.getElement(),
+        node = this.editor.getContentAreaContainer().childNodes[0];
 
       if (textarea && node)
         node.tabIndex = textarea.tabIndex;
       if (focus)
-        editor.getBody().focus();
+        this.editor.getBody().focus();
     }
-  }
-}
+  };
+
+  // switch html/plain mode
+  this.toggle = function(ishtml)
+  {
+    var curr, content, result,
+      // these non-printable chars are not removed on text2html and html2text
+      // we can use them as temp signature replacement
+      sig_mark = "\u0002\u0003",
+      input = $('#' + this.id),
+      signature = rcmail.env.identity ? rcmail.env.signatures[rcmail.env.identity] : null,
+      is_sig = signature && signature.text && signature.text.length > 1;
+
+    // apply spellcheck changes if spell checker is active
+    this.spellcheck_stop();
+
+    if (ishtml) {
+      content = input.val();
+
+      // replace current text signature with temp mark
+      if (is_sig)
+        content = content.replace(signature.text, sig_mark);
+
+      // convert to html
+      result = rcmail.plain2html(content, function(data) {
+        // replace signature mark with html version of the signature
+        if (is_sig)
+          data = data.replace(sig_mark, '<div id="_rc_sig">' + signature.html + '</div>');
+
+        input.val(data);
+        tinymce.execCommand('mceAddEditor', false, ref.id);
+
+        setTimeout(function() {
+          if (ref.editor) {
+            if (rcmail.env.default_font)
+              $(ref.editor.getBody()).css('font-family', rcmail.env.default_font);
+            // #1486593
+            ref.tabindex(true);
+          }
+        }, 500);
+      });
+    }
+    else if (this.editor) {
+      if (is_sig) {
+        // get current version of signature, we'll need it in
+        // case of html2text conversion abort
+        if (curr = this.editor.dom.get('_rc_sig'))
+          curr = curr.innerHTML;
+
+        // replace current signature with some non-printable characters
+        // we use non-printable characters, because this replacement
+        // is visible to the user
+        // doing this after getContent() would be hard
+        this.editor.dom.setHTML('_rc_sig', sig_mark);
+      }
 
-// switch html/plain mode
-function rcmail_toggle_editor(select, textAreaId)
-{
-  var ishtml = select.tagName != 'SELECT' ? select.checked : select.value == 'html',
-    res = rcmail.command('toggle-editor', {id: textAreaId, mode: ishtml ? 'html' : 'plain'});
-
-  if (!res) {
-    if (select.tagName == 'SELECT')
-      select.value = 'html';
-    else if (select.tagName == 'INPUT')
-      select.checked = true;
-  }
-  else if (ishtml) {
-    // #1486593
-    setTimeout("rcmail_editor_tabindex(true);", 500);
-  }
-  else if (rcmail.env.composebody) {
-    rcube_find_object(rcmail.env.composebody).focus();
-  }
-}
+      // get html content
+      content = this.editor.getContent();
 
-// image selector
-function rcmail_file_browser_callback(field_name, url, type, win)
-{
-  var i, elem, dialog, list = [], editor = tinyMCE.activeEditor;
-
-  // open image selector dialog
-  dialog = editor.windowManager.open({
-    title: rcmail.gettext('select' + type),
-    width: 500,
-    height: 300,
-    html: '<div id="image-selector-list"><ul></ul></div>'
-      + '<div id="image-selector-form"><div id="image-upload-button" class="mce-widget mce-btn" role="button"></div></div>',
-    buttons: [{text: 'Cancel', onclick: function() { rcmail_file_browser_close(); }}]
-  });
-
-  rcmail.env.file_browser_field = field_name;
-  rcmail.env.file_browser_type = type;
-
-  // fill images list with available images
-  for (i in rcmail.env.attachments) {
-    if (elem = rcmail_file_browser_entry(i, rcmail.env.attachments[i])) {
-      list.push(elem);
+      // convert html to text
+      result = rcmail.html2plain(content, function(data) {
+        tinymce.execCommand('mceRemoveEditor', false, ref.id);
+        ref.editor = null;
+
+        // replace signture mark with text version of the signature
+        if (is_sig)
+          data = data.replace(sig_mark, "\n" + signature.text);
+
+        input.val(data).focus();
+      });
+
+      // bring back current signature
+      if (!result && curr)
+        this.editor.dom.setHTML('_rc_sig', curr);
     }
-  }
 
-  if (list.length) {
-    $('#image-selector-list > ul').append(list);
-  }
+    return result;
+  };
 
-  // add hint about max file size (in dialog footer)
-  $('div.mce-abs-end', dialog.getEl()).append($('<div class="hint">').text($('div.hint', rcmail.gui_objects.uploadform).text()));
-
-  // enable (smart) upload button
-  elem = $('#image-upload-button').append($('<span>').text(rcmail.gettext('add' + type)));
-  hack_file_input(elem, rcmail.gui_objects.uploadform);
-
-  // enable drag-n-drop area
-  if (rcmail.gui_objects.filedrop && rcmail.env.filedrop && ((window.XMLHttpRequest && XMLHttpRequest.prototype && XMLHttpRequest.prototype.sendAsBinary) || window.FormData)) {
-    rcmail.env.old_file_drop = rcmail.gui_objects.filedrop;
-    rcmail.gui_objects.filedrop = $('#image-selector-form');
-    rcmail.gui_objects.filedrop.addClass('droptarget')
-      .bind('dragover dragleave', function(e) {
-        e.preventDefault();
-        e.stopPropagation();
-        $(this)[(e.type == 'dragover' ? 'addClass' : 'removeClass')]('hover');
-      })
-      .get(0).addEventListener('drop', function(e) { return rcmail.file_dropped(e); }, false);
-  }
+  // start spellchecker
+  this.spellcheck_start = function()
+  {
+    if (this.editor) {
+      tinymce.execCommand('mceSpellCheck', true);
+      this.spellcheck_observer();
+    }
+    else if (this.spellchecker && this.spellchecker.spellCheck) {
+      this.spellchecker.spellCheck();
+    }
+  };
 
-  // register handler for successful file upload
-  if (!rcmail.env.file_dialog_event) {
-    rcmail.env.file_dialog_event = true;
-    rcmail.addEventListener('fileuploaded', function(attr) {
-      var elem;
-      if (elem = rcmail_file_browser_entry(attr.name, attr.attachment)) {
-        $('#image-selector-list > ul').prepend(elem);
-      }
-    });
-  }
-}
+  // stop spellchecker
+  this.spellcheck_stop = function()
+  {
+    var ed = this.editor;
 
-// close file browser window
-function rcmail_file_browser_close(url)
-{
-  if (url)
-    $('#' + rcmail.env.file_browser_field).val(url);
+    if (ed) {
+      if (ed.plugins && ed.plugins.spellchecker && this.spellcheck_active)
+        ed.execCommand('mceSpellCheck');
+        this.spellcheck_observer();
+    }
+    else if (ed = this.spellchecker) {
+      if (ed.state && ed.state != 'ready' && ed.state != 'no_error_found')
+        $(ed.spell_span).trigger('click');
+    }
+  };
+
+  // spellchecker state
+  this.spellcheck_state = function()
+  {
+    var ed;
+
+    if (this.editor)
+      return this.spellcheck_active;
+    else if ((ed = this.spellchecker) && ed.state)
+      return ed.state != 'ready' && ed.state != 'no_error_found';
+  };
+
+  // resume spellchecking, highlight provided mispellings without new ajax request
+  this.spellcheck_resume = function(data)
+  {
+    var ed = this.editor;
+
+    if (ed) {
+      ed.settings.spellchecker_callback = function(name, text, done, error) { done(data); };
+      ed.execCommand('mceSpellCheck');
+      ed.settings.spellchecker_callback = null;
+
+      this.spellcheck_observer();
+    }
+    else if (ed = this.spellchecker) {
+      ed.prepare(false, true);
+      ed.processData(data);
+    }
+  };
 
-  tinyMCE.activeEditor.windowManager.close();
+  // get selected (spellcheker) language
+  this.get_language = function()
+  {
+    if (this.editor) {
+      return this.editor.settings.spellchecker_language || rcmail.env.spell_lang;
+    }
+    else if (this.spellchecker) {
+      return GOOGIE_CUR_LANG;
+    }
+  };
 
-  if (rcmail.env.old_file_drop)
-    rcmail.gui_objects.filedrop = rcmail.env.old_file_drop;
-}
+  // set language for spellchecking
+  this.set_language = function(lang)
+  {
+    var ed = this.editor;
 
-// creates file browser entry
-function rcmail_file_browser_entry(file_id, file)
-{
-  if (!file.complete || !file.mimetype) {
-    return;
-  }
+    if (ed) {
+      ed.settings.spellchecker_language = lang;
+    }
+    if (ed = this.spellchecker) {
+      ed.setCurrentLanguage(lang);
+    }
+  };
 
-  if (file.mimetype.startsWith('image/')) {
-    var href = rcmail.env.comm_path+'&_id='+rcmail.env.compose_id+'&_action=display-attachment&_file='+file_id,
-      img = $('<img>').attr({title: file.name, src: href + '&_thumbnail=1'});
+  // replace selection with text snippet
+  this.replace = function(text)
+  {
+    var ed = this.editor;
 
-    return $('<li>').data('url', href)
-      .append($('<span class="img">').append(img))
-      .append($('<span class="name">').text(file.name))
-      .click(function() { rcmail_file_browser_close($(this).data('url')); });
-  }
-}
+    // insert into tinymce editor
+    if (ed) {
+      ed.getWin().focus(); // correct focus in IE & Chrome
+      ed.selection.setContent(rcmail.quote_html(text).replace(/\r?\n/g, '<br/>'), { format:'text' });
+    }
+    // replace selection in compose textarea
+    else if (ed = rcube_find_object(this.id)) {
+      var selection = $(ed).is(':focus') ? rcmail.get_input_selection(ed) : { start:0, end:0 },
+        inp_value = ed.value;
+        pre = inp_value.substring(0, selection.start),
+        end = inp_value.substring(selection.end, inp_value.length);
+
+      // insert response text
+      ed.value = pre + text + end;
+
+      // set caret after inserted text
+      rcmail.set_caret_pos(ed, selection.start + text.length);
+      ed.focus();
+    }
+  };
+
+  // get selected text (if no selection returns all text) from the editor
+  this.get_content = function(selected, plain)
+  {
+    // apply spellcheck changes if spell checker is active
+    this.spellcheck_stop();
+
+    var sigstart, ed = this.editor,
+      format = plain ? 'text' : 'html',
+      text = '', strip = false;
+
+    // get selected text from tinymce editor
+    if (ed) {
+      ed.getWin().focus(); // correct focus in IE & Chrome
+      if (selected)
+        text = ed.selection.getContent({format: format});
+
+      if (!text) {
+        text = ed.getContent({format: format});
+        strip = true;
+      }
+    }
+    // get selected text from compose textarea
+    else if (ed = rcube_find_object(this.id)) {
+      if (selected && $(ed).is(':focus')) {
+        text = rcmail.get_input_selection(ed).text;
+      }
 
-// create smart files upload button
-function hack_file_input(elem, clone_form)
-{
-  var link = $(elem),
-    file = $('<input>'),
-    form = $('<form>').attr({method: 'post', enctype: 'multipart/form-data'}),
-    offset = link.offset();
-
-  // clone existing upload form
-  if (clone_form) {
-    file.attr('name', $('input[type="file"]', clone_form).attr('name'));
-    form.attr('action', $(clone_form).attr('action'))
-      .append($('<input>').attr({type: 'hidden', name: '_token', value: rcmail.env.request_token}));
-  }
+      if (!text) {
+        text = ed.value;
+        strip = true;
+      }
+    }
 
-  function move_file_input(e) {
-    file.css({top: (e.pageY - offset.top - 10) + 'px', left: (e.pageX - offset.left - 10) + 'px'});
-  }
+    // strip off signature
+    if (strip) {
+      sigstart = text.indexOf('-- \n');
+      if (sigstart > 0) {
+        text = text.substring(0, sigstart);
+      }
+    }
 
-  file.attr({type: 'file', multiple: 'multiple', size: 5, title: ''})
-    .change(function() { rcmail.upload_file(form, 'upload'); })
-    .click(function() { setTimeout(function() { link.mouseleave(); }, 20); })
-    // opacity:0 does the trick, display/visibility doesn't work
-    .css({opacity: 0, cursor: 'pointer', position: 'relative', outline: 'none'})
-    .appendTo(form);
-
-  // In FF and IE we need to move the browser file-input's button under the cursor
-  // Thanks to the size attribute above we know the length of the input field
-  if (navigator.userAgent.match(/Firefox|MSIE/))
-    file.css({marginLeft: '-80px'});
-
-  // Note: now, I observe problem with cursor style on FF < 4 only
-  link.css({overflow: 'hidden', cursor: 'pointer'})
-    .mouseenter(function() { this.__active = true; })
-    // place button under the cursor
-    .mousemove(function(e) {
-      if (this.__active)
-        move_file_input(e);
-      // move the input away if button is disabled
+    return text;
+  };
+
+  // change user signature text
+  this.change_signature = function(id, show_sig)
+  {
+    var cursor_pos, p = -1,
+      input_message = $('#' + this.id),
+      message = input_message.val(),
+      sig = rcmail.env.identity;
+
+    if (!this.editor) { // plain text mode
+      // remove the 'old' signature
+      if (show_sig && sig && rcmail.env.signatures && rcmail.env.signatures[sig]) {
+        sig = rcmail.env.signatures[sig].text;
+        sig = sig.replace(/\r\n/g, '\n');
+
+        p = rcmail.env.top_posting ? message.indexOf(sig) : message.lastIndexOf(sig);
+        if (p >= 0)
+          message = message.substring(0, p) + message.substring(p+sig.length, message.length);
+      }
+      // add the new signature string
+      if (show_sig && rcmail.env.signatures && rcmail.env.signatures[id]) {
+        sig = rcmail.env.signatures[id].text;
+        sig = sig.replace(/\r\n/g, '\n');
+
+        if (rcmail.env.top_posting) {
+          if (p >= 0) { // in place of removed signature
+            message = message.substring(0, p) + sig + message.substring(p, message.length);
+            cursor_pos = p - 1;
+          }
+          else if (!message) { // empty message
+            cursor_pos = 0;
+            message = '\n\n' + sig;
+          }
+          else if (pos = rcmail.get_caret_pos(input_message.get(0))) { // at cursor position
+            message = message.substring(0, pos) + '\n' + sig + '\n\n' + message.substring(pos, message.length);
+            cursor_pos = pos;
+          }
+          else { // on top
+            cursor_pos = 0;
+            message = '\n\n' + sig + '\n\n' + message.replace(/^[\r\n]+/, '');
+          }
+        }
+        else {
+          message = message.replace(/[\r\n]+$/, '');
+          cursor_pos = !rcmail.env.top_posting && message.length ? message.length+1 : 0;
+          message += '\n\n' + sig;
+        }
+      }
       else
-        $(this).mouseleave();
-    })
-    .mouseleave(function() {
-      file.css({top: '-10000px', left: '-10000px'});
-      this.__active = false;
-    })
-    .click(function(e) {
-      // forward click if mouse-enter event was missed
-      if (!this.__active) {
-        this.__active = true;
-        move_file_input(e);
-        file.trigger(e);
+        cursor_pos = rcmail.env.top_posting ? 0 : message.length;
+
+      input_message.val(message);
+
+      // move cursor before the signature
+      rcmail.set_caret_pos(input_message.get(0), cursor_pos);
+    }
+    else if (show_sig && rcmail.env.signatures) {  // html
+      var sigElem = this.editor.dom.get('_rc_sig');
+
+      // Append the signature as a div within the body
+      if (!sigElem) {
+        var body = this.editor.getBody(),
+          doc = this.editor.getDoc();
+
+        sigElem = doc.createElement('div');
+        sigElem.setAttribute('id', '_rc_sig');
+
+        if (rcmail.env.top_posting) {
+          // if no existing sig and top posting then insert at caret pos
+          this.editor.getWin().focus(); // correct focus in IE & Chrome
+
+          var node = this.editor.selection.getNode();
+          if (node.nodeName == 'BODY') {
+            // no real focus, insert at start
+            body.insertBefore(sigElem, body.firstChild);
+            body.insertBefore(doc.createElement('br'), body.firstChild);
+          }
+          else {
+            body.insertBefore(sigElem, node.nextSibling);
+            body.insertBefore(doc.createElement('br'), node.nextSibling);
+          }
+        }
+        else {
+          body.appendChild(sigElem);
+        }
+      }
+
+      if (rcmail.env.signatures[id]) {
+        sigElem.innerHTML = rcmail.env.signatures[id].html;
       }
-    })
-    .mouseleave()
-    .append(form);
+    }
+  };
+
+  // trigger content save
+  this.save = function()
+  {
+    if (this.editor) {
+      this.editor.save();
+    }
+  };
+
+  // focus the editing area
+  this.focus = function()
+  {
+    (this.editor || rcube_find_object(this.id)).focus();
+  };
+
+  // image selector
+  this.file_browser_callback = function(field_name, url, type)
+  {
+    var i, elem, dialog, list = [];
+
+    // open image selector dialog
+    dialog = this.editor.windowManager.open({
+      title: rcmail.gettext('select' + type),
+      width: 500,
+      height: 300,
+      html: '<div id="image-selector-list"><ul></ul></div>'
+        + '<div id="image-selector-form"><div id="image-upload-button" class="mce-widget mce-btn" role="button"></div></div>',
+      buttons: [{text: 'Cancel', onclick: function() { ref.file_browser_close(); }}]
+    });
+
+    rcmail.env.file_browser_field = field_name;
+    rcmail.env.file_browser_type = type;
+
+    // fill images list with available images
+    for (i in rcmail.env.attachments) {
+      if (elem = ref.file_browser_entry(i, rcmail.env.attachments[i])) {
+        list.push(elem);
+      }
+    }
+
+    if (list.length) {
+      $('#image-selector-list > ul').append(list);
+    }
+
+    // add hint about max file size (in dialog footer)
+    $('div.mce-abs-end', dialog.getEl()).append($('<div class="hint">').text($('div.hint', rcmail.gui_objects.uploadform).text()));
+
+    // enable (smart) upload button
+    elem = $('#image-upload-button').append($('<span>').text(rcmail.gettext('add' + type)));
+    this.hack_file_input(elem, rcmail.gui_objects.uploadform);
+
+    // enable drag-n-drop area
+    if (rcmail.gui_objects.filedrop && rcmail.env.filedrop && ((window.XMLHttpRequest && XMLHttpRequest.prototype && XMLHttpRequest.prototype.sendAsBinary) || window.FormData)) {
+      rcmail.env.old_file_drop = rcmail.gui_objects.filedrop;
+      rcmail.gui_objects.filedrop = $('#image-selector-form');
+      rcmail.gui_objects.filedrop.addClass('droptarget')
+        .bind('dragover dragleave', function(e) {
+          e.preventDefault();
+          e.stopPropagation();
+          $(this)[(e.type == 'dragover' ? 'addClass' : 'removeClass')]('hover');
+        })
+        .get(0).addEventListener('drop', function(e) { return rcmail.file_dropped(e); }, false);
+    }
+
+    // register handler for successful file upload
+    if (!rcmail.env.file_dialog_event) {
+      rcmail.env.file_dialog_event = true;
+      rcmail.addEventListener('fileuploaded', function(attr) {
+        var elem;
+        if (elem = ref.file_browser_entry(attr.name, attr.attachment)) {
+          $('#image-selector-list > ul').prepend(elem);
+        }
+      });
+    }
+  };
+
+  // close file browser window
+  this.file_browser_close = function(url)
+  {
+    if (url)
+      $('#' + rcmail.env.file_browser_field).val(url);
+
+    this.editor.windowManager.close();
+
+    if (rcmail.env.old_file_drop)
+      rcmail.gui_objects.filedrop = rcmail.env.old_file_drop;
+  };
+
+  // creates file browser entry
+  this.file_browser_entry = function(file_id, file)
+  {
+    if (!file.complete || !file.mimetype) {
+      return;
+    }
+
+    if (file.mimetype.startsWith('image/')) {
+      var href = rcmail.env.comm_path+'&_id='+rcmail.env.compose_id+'&_action=display-attachment&_file='+file_id,
+        img = $('<img>').attr({title: file.name, src: href + '&_thumbnail=1'});
+
+      return $('<li>').data('url', href)
+        .append($('<span class="img">').append(img))
+        .append($('<span class="name">').text(file.name))
+        .click(function() { ref.file_browser_close($(this).data('url')); });
+    }
+  };
+
+  // create smart files upload button
+  this.hack_file_input = function(elem, clone_form)
+  {
+    var link = $(elem),
+      file = $('<input>'),
+      form = $('<form>').attr({method: 'post', enctype: 'multipart/form-data'}),
+      offset = link.offset();
+
+    // clone existing upload form
+    if (clone_form) {
+      file.attr('name', $('input[type="file"]', clone_form).attr('name'));
+      form.attr('action', $(clone_form).attr('action'))
+        .append($('<input>').attr({type: 'hidden', name: '_token', value: rcmail.env.request_token}));
+    }
+
+    function move_file_input(e) {
+      file.css({top: (e.pageY - offset.top - 10) + 'px', left: (e.pageX - offset.left - 10) + 'px'});
+    }
+
+    file.attr({type: 'file', multiple: 'multiple', size: 5, title: ''})
+      .change(function() { rcmail.upload_file(form, 'upload'); })
+      .click(function() { setTimeout(function() { link.mouseleave(); }, 20); })
+      // opacity:0 does the trick, display/visibility doesn't work
+      .css({opacity: 0, cursor: 'pointer', position: 'relative', outline: 'none'})
+      .appendTo(form);
+
+    // In FF and IE we need to move the browser file-input's button under the cursor
+    // Thanks to the size attribute above we know the length of the input field
+    if (navigator.userAgent.match(/Firefox|MSIE/))
+      file.css({marginLeft: '-80px'});
+
+    // Note: now, I observe problem with cursor style on FF < 4 only
+    link.css({overflow: 'hidden', cursor: 'pointer'})
+      .mouseenter(function() { this.__active = true; })
+      // place button under the cursor
+      .mousemove(function(e) {
+        if (this.__active)
+          move_file_input(e);
+        // move the input away if button is disabled
+        else
+          $(this).mouseleave();
+      })
+      .mouseleave(function() {
+        file.css({top: '-10000px', left: '-10000px'});
+        this.__active = false;
+      })
+      .click(function(e) {
+        // forward click if mouse-enter event was missed
+        if (!this.__active) {
+          this.__active = true;
+          move_file_input(e);
+          file.trigger(e);
+        }
+      })
+      .mouseleave()
+      .append(form);
+  };
 }