/*==============================================================================
Wikiwyg - Turn any HTML div into a wikitext /and/ wysiwyg edit area.

DESCRIPTION:

Wikiwyg is a Javascript library that can be easily integrated into any
wiki or blog software. It offers the user multiple ways to edit/view a
piece of content: Wysiwyg, Wikitext, Raw-HTML and Preview.

The library is easy to use, completely object oriented, configurable and
extendable.

See the Wikiwyg documentation for details.

AUTHORS:

    Brian Ingerson <ingy@cpan.org>
    Chris Dent <cdent@burningchrome.com>
    Dave Rolsky <autarch@urth.org>
    Matt Liggett <mml@pobox.com>

COPYRIGHT:

    Copyright (c) 2005 Socialtext Corporation 
    655 High Street
    Palo Alto, CA 94301 U.S.A.
    All rights reserved.

Wikiwyg is free software. 

This library is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at
your option) any later version.

This library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
General Public License for more details.

    http://www.gnu.org/copyleft/lesser.txt

==============================================================================*/

/*==============================================================================
Developer's Notes:

TODO:
    * Release code to JSAN
    * Integrate back into a working Kwiki
    ** With a Wikiwyg.Kwiki subclass
    * Support IE
    * Merge config (default, class attributes, custom)
    * Finish toolbar
    ** Insert Link
    ** Insert Table
    ** Insert Image
    * add Rawhtml mode
    * Make toolbar button width configurable (for small text areas)
    * change escape_plus() to encodeURIComponent() (per rking)

REFACTOR:
    * Find a good way to call super methods

BUGS:
    * Control-key shortcuts don't work after preview (sometimes)

IDEAS:
    * Spike an integration with TiddlyWiki
    * Make a greasemonkey overlay for Flickr comments 
    * Spike integration with these wikis:
    ** Media Wiki
    ** TWiki
    ** MoinMoin
==============================================================================*/

/*==============================================================================
Wikiwyg - Primary Wikiwyg base class
==============================================================================*/

// Constructor and class methods
Wikiwyg = function() {};
Wikiwyg.VERSION = '0.10';

Wikiwyg.is_gecko = (navigator.userAgent.toLowerCase().indexOf("gecko") != -1);
Wikiwyg.browserIsSupported = Wikiwyg.is_gecko;

// Config attributes
// Override these values in a subclass to control which modes
Wikiwyg.prototype.toolbarClass = 'Wikiwyg.Toolbar';
Wikiwyg.prototype.modeList = [ 
    'Wikiwyg.Wysiwyg',
    'Wikiwyg.Wikitext',
    'Wikiwyg.Preview'
];

// Wikiwyg environment setup public methods
Wikiwyg.prototype.createWikiwygArea = function(div, config) {
    this.set_config(config);
    this.initializeObject(div);
};

Wikiwyg.prototype.defaultConfig = function() {
    return {
        baseUri: '',
        doubleClickToEdit: false,
    };
}

Wikiwyg.prototype.initializeObject = function(div) {
    if (! Wikiwyg.browserIsSupported) return;
    if (div.wikiwyg_enabled) return;
    div.wikiwyg_enabled = true;
    this.div = div;
    this.divHeight = this.div.clientHeight;

    this.mode_objects = {};
    for (var i in this.modeList) {
        var class_name = this.modeList[i];
        if(class_name.match) {
            var mode_object = eval('new ' + class_name + '()');
            mode_object.initializeObject(this);
            this.mode_objects[class_name] = mode_object;
            if (! this.first_mode) {
                this.first_mode = mode_object;
            }
        }
    }

    if (this.toolbarClass) {
        this.toolbarObject = eval('new ' + this.toolbarClass + '()');
        this.toolbarObject.initializeObject(this);
        this.insert_div_before(this.toolbarObject.div);
    }

    // These objects must be _created_ before the toolbar is created
    // but _inserted_ after.
    for (var key in this.mode_objects) {
        var mode_object = this.mode_objects[key];
        if(mode_object.div)
          this.insert_div_before(mode_object.div);
    }

    if (this.config.doubleClickToEdit) {
        var self = this;
        this.div.ondblclick = function() { self.editMode() }; 
    }
}

// Wikiwyg environment setup private methods
Wikiwyg.prototype.set_config = function(user_config) {
    this.config = this.defaultConfig();
    if (user_config == null) return;
    for (var key in this.config) {
        if (user_config[key] != null)
            this.config[key] = user_config[key];
    }
}

Wikiwyg.prototype.insert_div_before = function(div) {
    div.style.display = 'none';
    if(this.div.parentNode)
      this.div.parentNode.insertBefore(div, this.div);
}

// Wikiwyg actions - public interface methods
Wikiwyg.prototype.saveChanges = function() {
    alert('Wikiwyg.prototype.saveChanges not subclassed');
}

// Wikiwyg actions - public methods
Wikiwyg.prototype.editMode = function() {
    this.current_mode = this.first_mode;
    this.current_mode.enableThis();
    this.current_mode.fromHtml(this.div.innerHTML);
    this.toolbarObject.resetModeSelector();
}

Wikiwyg.prototype.displayMode = function() {
    for (var key in this.mode_objects) {
        if (this.mode_objects[key].className)
        this.mode_objects[key].disableThis();
    }
    this.toolbarObject.disableThis();
    this.div.style.display = 'block';
    this.divHeight = this.div.clientHeight;
}

Wikiwyg.prototype.switchMode = function(new_mode_key) {
    var new_mode = this.mode_objects[new_mode_key];
    var old_mode = this.current_mode;
    var self = this;
    old_mode.toHtml(
        function(html) {
            new_mode.fromHtml(html);
            old_mode.disableThis();
            new_mode.enableThis();
            self.current_mode = new_mode;
        }
    );
}

Wikiwyg.prototype.cancelEdit = function() {
    this.displayMode();
}

Wikiwyg.prototype.fromHtml = function(html) {
    this.div.innerHTML = html;
}

// Class level helper methods
Wikiwyg.unique_id_base = 0;
Wikiwyg.createUniqueId = function() {
    return 'wikiwyg_' + Wikiwyg.unique_id_base++;
}

Wikiwyg.get_live_update = function(url, query_string, callback) {
    var req = new XMLHttpRequest()
    req.open('GET', url + '?' + query_string)
    req.onreadystatechange = function() {
        if (req.readyState == 4 && req.status == 200) {
            callback(req.responseText)
        }
    }
    req.send(null)
}

Wikiwyg.live_update = function(url, postdata, callback) {
    var req = new XMLHttpRequest()
    req.open('POST', url)
    req.onreadystatechange = function() {
        if (req.readyState == 4 && req.status == 200) {
            callback(req.responseText)
        }
    }
    req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded")
    req.send(postdata)
}

Wikiwyg.escape_plus = function(string) {
    string = string.toString()
    string = escape(string)
    string = string.replace(/\+/g, '%2B');
    return string
}

/*==============================================================================
This class provides toolbar support
==============================================================================*/
Wikiwyg.Toolbar = function() {}
Wikiwyg.Toolbar.prototype.initializeObject = function(wikiwyg) {
    this.wikiwyg = wikiwyg;
    this.div = document.createElement('div');
    this.div.innerHTML = '\
<table class="wikiwyg_background" \
       cellpadding="0" cellspacing="0" width="100%"> \
<tr><td colspan="100"></td></tr><tr></tr></table>';

    var trs = this.div.getElementsByTagName('tr');
    this.control_row = trs[0];
    this.button_row = trs[1];

    this.control_cell =
        this.control_row.getElementsByTagName('td')[0];

    this.setControls();
    this.setButtons();

    // XXX - Hack to get buttons flush left - use css
    var td = document.createElement('td');
    td.setAttribute('width', '100%');
    this.button_row.insertBefore(td, null);
}

Wikiwyg.Toolbar.prototype.enableThis = function() {
    this.div.style.display = 'block';
}

Wikiwyg.Toolbar.prototype.disableThis = function() {
    this.div.style.display = 'none';
}

Wikiwyg.Toolbar.prototype.setControls = function() {
    this.addControlItem('Save', 'saveChanges');
    this.addControlItem('Cancel', 'cancelEdit');
    this.addModeSelector();
}

Wikiwyg.Toolbar.prototype.setButtons = function() {
    this.add_styles();
    this.add_button('bold');
    this.add_button('italic');
    this.add_button('underline');
    this.add_button('strike', 'strikethrough', 'Strike Through');
    this.add_separator();
    this.add_button('hr', 'inserthorizontalrule', 'Horizontal Rule');
    this.add_separator();
    this.add_button('ordered', 'insertorderedlist',
                            'Ordered list');
    this.add_button('unordered', 'insertunorderedlist',
                            'Unordered list');
    this.add_separator();
    this.add_button('outdent');
    this.add_button('indent');
    this.add_separator();
    this.add_help_button();
}

Wikiwyg.Toolbar.prototype.add_button = function(type, command, label) {
    if (!command)
        command = type;
    if (!label)
        label = type;
    var td = document.createElement('td');
    var base = this.wikiwyg.config.baseUri;
    td.innerHTML =
      '<img class="wikiwyg_img" src="' + base + 'images/' + type + '.gif" \
      width="25" height="24" \
      alt="' + label + '" title="' + label + '">';

    var self = this;
    td.onclick = function() {
        self.wikiwyg.current_mode.process_command(command, null);
    };
    this.button_row.insertBefore(td, null);
}

Wikiwyg.Toolbar.prototype.add_help_button = function() {
    var td = document.createElement('td');
    var base = this.wikiwyg.config.baseUri;
    td.innerHTML = 
      '<a target="wikiwyg-about" href="http://www.wikiwyg.net/about/"> \
      <img class="wikiwyg_img" src="' + base + 'images/help.gif" \
      width="20" height="20" alt="Help" title="Help"></a>';

    var self = this;
    td.onclick = function() {
        var wikiwyg = self.wikiwyg;
        wikiwyg.current_mode.process_command(command, null);
    };
    this.button_row.insertBefore(td, null);
}

Wikiwyg.Toolbar.prototype.add_separator = function() {
    var td = document.createElement('td');
    var base = this.wikiwyg.config.baseUri;
    td.innerHTML = '\
<img class="wikiwyg_separator" src="' + base + 'images/blackdot.gif"\
     width="1" height="20" border="0" alt="">';
    this.button_row.insertBefore(td, null);
}

Wikiwyg.Toolbar.prototype.addControlItem = function(text, method) {
    var span = document.createElement('span');
    span.setAttribute('class', 'wikiwyg_control_link');

    var link = document.createElement('a');
    span.appendChild(link);

    link.setAttribute('href', '#');
    link.innerHTML = text;
    
    var self = this;
    link.onclick = function() { eval('self.wikiwyg.' + method + '()'); return false };

    this.control_cell.insertBefore(span, null);
}

Wikiwyg.Toolbar.prototype.resetModeSelector = function() {
    this.firstModeRadio.click();
}

Wikiwyg.Toolbar.prototype.addModeSelector = function() {
    var div = document.createElement('span');

    var radio_name = Wikiwyg.createUniqueId();
    for (var i in this.wikiwyg.modeList) {
        var class_name = this.wikiwyg.modeList[i];
        if(class_name.match) {
          var mode_object = this.wikiwyg.mode_objects[class_name];
          var radio = document.createElement('input');
          if (!this.firstModeRadio)
              this.firstModeRadio = radio;

          radio.setAttribute('type', 'radio');
          radio.setAttribute('name', radio_name);
          var radio_id = Wikiwyg.createUniqueId();
          radio.setAttribute('id', radio_id);
          radio.setAttribute('value', mode_object.className);

          if (i == 0) {
              radio.setAttribute('checked', 'checked');
          }

          var self = this;
          radio.onclick = function() { 
              self.wikiwyg.switchMode(this.value);
          };

          var label = document.createElement('label');
          label.setAttribute('for', radio_id);
          label.innerHTML = mode_object.modeDescription;

          div.appendChild(radio);
          div.appendChild(label);
        }
    }
    this.control_cell.insertBefore(div, null);
}

Wikiwyg.Toolbar.prototype.add_styles = function() {
    var td = document.createElement('td');
    td.innerHTML = '\
<select> \
<option value="">[Style]</option> \
<option value="p">Paragraph &lt;p&gt;</option> \
<option value="h1">Heading 1 &lt;h1&gt;</option> \
<option value="h2">Heading 2 &lt;h2&gt;</option> \
<option value="h3">Heading 3 &lt;h3&gt;</option> \
<option value="h4">Heading 4 &lt;h4&gt;</option> \
<option value="h5">Heading 5 &lt;h5&gt;</option> \
<option value="h6">Heading 6 &lt;h6&gt;</option> \
<option value="pre">Formatted &lt;pre&gt;</option> \
</select> \
';
    this.styleSelect = td.getElementsByTagName('select')[0];
    var self = this;
    this.styleSelect.onchange = function() { 
        self.wikiwyg.current_mode.set_style(this.value) 
    };
    this.button_row.insertBefore(td, null);
}

/*==============================================================================
Base class for Wikiwyg Mode classes
==============================================================================*/
Wikiwyg.Mode = function() {}

Wikiwyg.Mode.prototype.enableThis = function() {
    this.div.style.display = 'block';
    this.wikiwyg.toolbarObject.enableThis();
    this.setupThis();
    this.wikiwyg.div.style.display = 'none';
}

Wikiwyg.Mode.prototype.disableThis = function() {
    this.div.style.display = 'none';
}

Wikiwyg.Mode.prototype.setupThis = function() {}

/*==============================================================================
This mode supports a DesignMode wysiwyg editor with toolbar buttons
==============================================================================*/
Wikiwyg.Wysiwyg = function() {}

Wikiwyg.Wysiwyg.prototype = new Wikiwyg.Mode();

Wikiwyg.Wysiwyg.prototype.className = 'Wikiwyg.Wysiwyg';
Wikiwyg.Wysiwyg.prototype.modeDescription = 'Wysiwyg';

Wikiwyg.Wysiwyg.prototype.initializeObject = function(wikiwyg) {
    this.wikiwyg = wikiwyg;
    this.div = document.createElement('div');
    this.div.innerHTML =
        '<iframe width="100%"><html><head><link rel="stylesheet" type="text/css" href="/obikicss/obiki.css" /></head><body></body></html></iframe>';
    this.edit_iframe = this.div.getElementsByTagName('iframe')[0];
}

Wikiwyg.Wysiwyg.prototype.rawHtml = function() {
    return this.edit_iframe.contentWindow.document.body.innerHTML;
}

Wikiwyg.Wysiwyg.prototype.fromHtml = function(html) {
    this.edit_iframe.contentWindow.document.body.innerHTML = html;
}

Wikiwyg.Wysiwyg.prototype.toHtml = function(func) {
    var html = this.edit_iframe.contentWindow.document.body.innerHTML;
    func(html);
}

Wikiwyg.Wysiwyg.prototype.setupThis = function() {
    this.edit_iframe.style.height =
      this.wikiwyg.divHeight +
      this.wikiwyg.toolbarObject.div.clientHeight;

    var doc = this.edit_iframe.contentWindow.document;         
    this.edit_iframe.contentDocument.designMode = "on";
    doc.addEventListener("keypress", this.get_key_press_function(), true);
}

Wikiwyg.Wysiwyg.prototype.process_command = function(command, option) {
    var win = this.edit_iframe.contentWindow;         
    try {
        win.focus();
        win.document.execCommand(command, false, option);
        win.focus();
    } 
    catch (e) {
    }
}

Wikiwyg.Wysiwyg.prototype.get_key_press_function = function() {
    var self = this;
    return function(evt) {
        last_key = evt;
        if (! evt.ctrlKey) return;
        var key = String.fromCharCode(evt.charCode).toLowerCase();
        var cmd = '';
        switch (key) {
            case 'b': cmd = "bold"; break;
            case 'i': cmd = "italic"; break;
            case 'u': cmd = "underline"; break;
            case 'd': cmd = "strikethrough"; break;
        };

        if (cmd) {
            self.process_command(cmd, null);
            evt.preventDefault();
            evt.stopPropagation();
        }
    };
}

Wikiwyg.Wysiwyg.prototype.set_style = function(style_name) {
    var idx = this.wikiwyg.toolbarObject.styleSelect.selectedIndex;
    // First one is always a label
    if (idx != 0)
        this.process_command('formatblock', style_name);
    this.wikiwyg.toolbarObject.styleSelect.selectedIndex = 0;
}

/*==============================================================================
This mode supports a textarea editor with toolbar buttons.
==============================================================================*/
Wikiwyg.Wikitext = function() {}

Wikiwyg.Wikitext.prototype = new Wikiwyg.Mode();

// XXX - we hate this but cannot find a way to get this dynamically
Wikiwyg.Wikitext.prototype.className = 'Wikiwyg.Wikitext';
Wikiwyg.Wikitext.prototype.modeDescription = 'Wikitext';

Wikiwyg.Wikitext.prototype.setupThis = function() {
    this.textarea.style.width = '100%';
    this.textarea.style.height = '200px';
}

Wikiwyg.Wikitext.prototype.initializeObject = function(wikiwyg) {
    this.wikiwyg = wikiwyg;
    this.div = document.createElement('div');
    this.div.innerHTML = '<textarea></textarea>';
    this.textarea = this.div.getElementsByTagName('textarea')[0];
    this.area = this.textarea;
}

Wikiwyg.Wikitext.prototype.toHtml = function(func) {
    var wikitext = this.textarea.value;
    this.convertWikitextToHtml(wikitext, func);
}

Wikiwyg.Wikitext.prototype.fromHtml = function(html) {
    this.textarea.value = 'Loading...';
    var textarea = this.textarea;
    this.convertHtmlToWikitext(
        html, 
        function(value) { textarea.value = value }
    );
}

// These two conversion routines are for demo purposes only. They need to
// be implemented in a subclass of Wikiwyg.Wikitext.
Wikiwyg.Wikitext.prototype.convertWikitextToHtml = function(wikitext, func) {
    func('<p>The Wikitext editor was invoked...</p>\n' + this.copyhtml);
}

Wikiwyg.Wikitext.prototype.convertHtmlToWikitext = function(html, func) {
    this.copyhtml = html;
    value = '\
This default implementation cannot convert HTML to Wikitext.\n\
\n\
But here is some sample demo text anyway:\n\
\n\
* *Bold*\n\
* /Italic/\n\
* _Underline_\n\
';
    func(value);
}

Wikiwyg.Wikitext.prototype.process_command = function(command, option) {
    eval("this.do_" + command + "()");
}

Wikiwyg.Wikitext.prototype.set_style = function(style_name) {
    var idx = this.wikiwyg.toolbarObject.styleSelect.selectedIndex;
    // First one is always a label
    if (idx != 0)
        this.process_command(style_name);
    this.wikiwyg.toolbarObject.styleSelect.selectedIndex = 0;
}

Wikiwyg.Wikitext.phrase_end_re = /[\s\.\:\;\,\!\?\(\)]/;

// XXX this is getting absurd
Wikiwyg.Wikitext.prototype.find_left = function(t, selection_start, matcher) {
    var substring = t.substr(selection_start - 1, 1);
    var nextstring = t.substr(selection_start - 2, 1);
    if (selection_start == 0) 
        return selection_start;
    if (substring.match(matcher)) {
        // special case for word.word
        if ((substring != '.') || (nextstring.match(/\s/))) 
            return selection_start;
    }
    return this.find_left(t, selection_start - 1, matcher);
}  

Wikiwyg.Wikitext.prototype.find_right = function(t, selection_end, matcher) {
    var substring = t.substr(selection_end, 1);
    var nextstring = t.substr(selection_end + 1, 1);
    if (selection_end >= t.length)
        return selection_end;
    if (substring.match(matcher)) {
        // special case for word.word
        if ((substring != '.') || (nextstring.match(/\s/)))
            return selection_end;
    }
    return this.find_right(t, selection_end + 1, matcher);
}

Wikiwyg.Wikitext.prototype.getLines = function() {
    t = this.area;
    var selection_start = t.selectionStart;
    var selection_end = t.selectionEnd;

    if (selection_start == null || selection_end == null)
        return false

    var our_text = t.value.replace(/\r/g, '');
    selection = our_text.substr(selection_start,
        selection_end - selection_start);

    selection_start = this.find_right(our_text, selection_start, /[^\r\n]/);
    selection_end = this.find_left(our_text, selection_end, /[^\r\n]/);

    this.selection_start = this.find_left(our_text, selection_start, /[\r\n]/);
    this.selection_end = this.find_right(our_text, selection_end, /[\r\n]/);
    t.setSelectionRange(selection_start, selection_end);
    t.focus();

    this.start = our_text.substr(0,this.selection_start);
    this.sel = our_text.substr(this.selection_start, this.selection_end -
        this.selection_start);
    this.finish = our_text.substr(this.selection_end, our_text.length);

    return true;
}

Wikiwyg.Wikitext.prototype.alarm_on = function() {
    var area = this.area;
    var background = area.style.background;
    area.style.background = '#f88';

    function alarm_off() {
        area.style.background = background;
    }

    window.setTimeout(alarm_off, 250);
    area.focus()
}

Wikiwyg.Wikitext.prototype.getWords = function() {
    function is_insane(selection) {
        return selection.match(/\r?\n(\r?\n|\*+ |\#+ |\=+ )/);
    }   

    t = this.area;
    var selection_start = t.selectionStart;
    var selection_end = t.selectionEnd;
    if (selection_start == null || selection_end == null)
        return false;
        
    var our_text = t.value.replace(/\r/g, '');
    selection = our_text.substr(selection_start,
        selection_end - selection_start);

    selection_start = this.find_right(our_text, selection_start, /(\S|\r?\n)/);
    if (selection_start > selection_end)
        selection_start = selection_end;
    selection_end = this.find_left(our_text, selection_end, /(\S|\r?\n)/);
    if (selection_end < selection_start)
        selection_end = selection_start;

    if (is_insane(selection)) {
        this.alarm_on();
        return false;
    }

    this.selection_start =
        this.find_left(our_text, selection_start, Wikiwyg.Wikitext.phrase_end_re);
    this.selection_end =
        this.find_right(our_text, selection_end, Wikiwyg.Wikitext.phrase_end_re);

    t.setSelectionRange(this.selection_start, this.selection_end);
    t.focus();

    this.start = our_text.substr(0,this.selection_start);
    this.sel = our_text.substr(this.selection_start, this.selection_end -
        this.selection_start);
    this.finish = our_text.substr(this.selection_end, our_text.length);

    return true;
}

Wikiwyg.Wikitext.prototype.markup_is_on = function(start, finish) {
    return (this.sel.match(start) && this.sel.match(finish));
}

Wikiwyg.Wikitext.prototype.clean_selection = function(start, finish) {
    this.sel = this.sel.replace(start, '');
    this.sel = this.sel.replace(finish, '');
}

Wikiwyg.Wikitext.prototype.toggle_same_format = function(start, finish) {
    start = this.cleanRE(start);
    finish = this.cleanRE(finish);
    var start_re = new RegExp('^' + start);
    var finish_re = new RegExp(finish + '$');
    if (this.markup_is_on(start_re, finish_re)) {
        this.clean_selection(start_re, finish_re);
        return true;
    }
    return false;
}

Wikiwyg.Wikitext.prototype.cleanRE = function(string) {
    string = string.replace(/([\^\*\[\]\{\}])/g, '\\' + "$1");
    return string;
}

Wikiwyg.Wikitext.prototype.setTextandSelection = function(text, start, end) {
    this.area.value = text;
    this.area.setSelectionRange(start, end);
}

Wikiwyg.Wikitext.prototype.addMarkupWords =
function(markup_start, markup_finish, example) {
    if (this.toggle_same_format(markup_start, markup_finish)) {
        this.selection_end = this.selection_end -
            (markup_start.length + markup_finish.length);
        markup_start = '';
        markup_finish = '';
    }
    if (this.sel.length == 0) {
        if (example)
            this.sel = example;
        var text = this.start + markup_start +
            this.sel + markup_finish + this.finish;
        var start = this.selection_start + markup_start.length;
        var end = this.selection_end + markup_start.length + this.sel.length;
        this.setTextandSelection(text, start, end);
    } else {
        var text = this.start + markup_start + this.sel +
            markup_finish + this.finish;
        var start = this.selection_start;
        var end = this.selection_end + markup_start.length +
            markup_finish.length;
        this.setTextandSelection(text, start, end);
    }
    this.area.focus();
}

Wikiwyg.Wikitext.prototype.addMarkupLines = function(markup_start) {
    var start_pattern = markup_start;
    start_pattern = start_pattern.replace(/(\=+) /, '$1');
    var already_set_re = new RegExp("^" + this.cleanRE(start_pattern) + " *",
        'gm');
    var other_markup_re = /^(\=+ *|\* |# )/gm;
    if (this.sel.match(already_set_re))
        this.sel = this.sel.replace(already_set_re, '');
    else if (this.sel.match(other_markup_re))
        this.sel = this.sel.replace(other_markup_re, markup_start);
    else if (this.sel.length > 0)
        this.sel = this.sel.replace(/^(.*\S+)/gm, markup_start + '$1');
    else
        this.sel = markup_start;
    var text = this.start + this.sel + this.finish;
    var start = this.selection_start;
    var end = this.selection_start + this.sel.length;
    this.setTextandSelection(text, start, end);
    this.area.focus();
}

Wikiwyg.Wikitext.prototype.startline = function(markup_start) {
    var scroll_top = this.area.scrollTop;
    if (this.getLines())
        this.addMarkupLines(markup_start + ' ');
    this.area.scrollTop = scroll_top;
}

Wikiwyg.Wikitext.prototype.boundword = function(markup_start, markup_finish, example) {
    var scroll_top = this.area.scrollTop;
    if (markup_finish == undefined)
        markup_finish = markup_start;
    if (this.getWords())
        this.addMarkupWords(markup_start, markup_finish, example);
    this.area.scrollTop = scroll_top;
}

Wikiwyg.Wikitext.prototype.do_bold = function() {
    this.boundword('*');
}

Wikiwyg.Wikitext.prototype.do_italic = function() {
    this.boundword('/');
}

Wikiwyg.Wikitext.prototype.do_underline = function() {
    this.boundword('_');
}

Wikiwyg.Wikitext.prototype.do_strikethrough = function() {
    this.boundword('-');
}

Wikiwyg.Wikitext.prototype.do_p = function() {
}

Wikiwyg.Wikitext.prototype.do_pre = function() {
}

Wikiwyg.Wikitext.prototype.do_h1 = function() {
    this.startline('=');
}

Wikiwyg.Wikitext.prototype.do_h2 = function() {
    this.startline('==');
}

Wikiwyg.Wikitext.prototype.do_h3 = function() {
    this.startline('===');
}

Wikiwyg.Wikitext.prototype.do_h4 = function() {
    this.startline('====');
}

Wikiwyg.Wikitext.prototype.do_h5 = function() {
    this.startline('=====');
}

Wikiwyg.Wikitext.prototype.do_h6 = function() {
    this.startline('======');
}

Wikiwyg.Wikitext.prototype.do_insertorderedlist = function() {
    this.startline('#');
}

Wikiwyg.Wikitext.prototype.do_insertunorderedlist = function() {
    this.startline('*');
}

Wikiwyg.Wikitext.prototype.do_dent = function(method) {
    var scroll_top = this.area.scrollTop;
    if (! this.getLines()) {
        this.area.scrollTop = scroll_top;
        return;
    }

    if (method(this)) {
        var text = this.start + this.sel + this.finish;
        var start = this.selection_start;
        var end = this.selection_start + this.sel.length;
        this.setTextandSelection(text, start, end);
    }
    this.area.focus();
}

Wikiwyg.Wikitext.prototype.do_indent = function() {
    this.do_dent(
        function(that) {
            if (that.sel == '') return false;
            that.sel = that.sel.replace(/^(([\*\-\#])+(?=\s))/gm, '$2$1');
            that.sel = that.sel.replace(/^([\>\=])/gm, '$1$1');
            that.sel = that.sel.replace(/^([^\>\*\-\#\=\r\n])/gm, '> $1');
            that.sel = that.sel.replace(/^\={7,}/gm, '======');
            return true;
        }
    )
}

Wikiwyg.Wikitext.prototype.do_outdent = function() {
    this.do_dent(
        function(that) {
            if (that.sel == '') return false;
            that.sel = that.sel.replace(/^([\>\*\-\#\=] ?)/gm, '');
            return true;
        }
    )
}

Wikiwyg.Wikitext.prototype.do_inserthorizontalrule = function() {
    var t = this.area;
    var scroll_top = t.scrollTop;
    var selection_start = t.selectionStart;
    var text = t.value;
    this.selection_start = this.find_right(text, selection_start, /\r?\n/);
    this.selection_end = this.selection_start;
    t.setSelectionRange(this.selection_start, this.selection_start);
    t.focus();

    this.start = t.value.substr(0, this.selection_start);
    this.finish = t.value.substr(this.selection_end, t.value.length);
    var text = this.start + '\n----' + this.finish;
    var start = this.selection_start + 5;
    var end = this.selection_end + 5;
    this.setTextandSelection(text, start, end);
    t.scrollTop = scroll_top;
}

/*==============================================================================
This mode supports a preview of current changes
==============================================================================*/
Wikiwyg.Preview = function() {}

Wikiwyg.Preview.prototype = new Wikiwyg.Mode();

Wikiwyg.Preview.prototype.className = 'Wikiwyg.Preview';
Wikiwyg.Preview.prototype.modeDescription = 'Preview';

Wikiwyg.Preview.prototype.initializeObject = function(wikiwyg) {
    this.wikiwyg = wikiwyg;
    this.div = document.createElement('div');
    this.div.style.backgroundColor = 'lightyellow';
}

Wikiwyg.Preview.prototype.fromHtml = function(html) {
    this.div.innerHTML = html;
}

Wikiwyg.Preview.prototype.toHtml = function(func) {
    func(this.div.innerHTML);
}