define([
  //'jquery',
  //'RTWiki_WebHome_sharejs_textarea',
  //'RTWiki_ErrorBox',
  //'RTWiki_WebHome_chainpad'
  '/common/crypto.js',
  '/code/errorbox.js',
  '/common/messages.js',
  '/common/toolbar.js',
  '/common/chainpad.js',
  '/common/otaml.js',
  '/bower_components/jquery/dist/jquery.min.js'
], function(Crypto, ErrorBox, Messages, Toolbar) {
    var $ = window.jQuery;
    var ChainPad = window.ChainPad;
    var Otaml = window.Otaml;
    var module = { exports: {} };

    var LOCALSTORAGE_DISALLOW = 'rtwiki-disallow';

    // Number for a message type which will not interfere with chainpad.
    var MESSAGE_TYPE_ISAVED = 5000;

    // how often to check if the document has been saved recently
    var SAVE_DOC_CHECK_CYCLE = 20000;

    // how often to save the document
    var SAVE_DOC_TIME = 60000;

    // How long to wait before determining that the connection is lost.
    var MAX_LAG_BEFORE_DISCONNECT = 30000;

    var MAX_RECOVERABLE_ERRORS = 15;

    var warn = function (x) { };
    var debug = function (x) { };
    //debug = function (x) { console.log(x) };
    warn = function (x) { console.log(x); };
    var setStyle = function () {
        $('head').append([
            '<style>',
            '.rtwiki-toolbar {',
            '    width: 100%;',
            '    color: #666;',
            '    font-weight: bold;',
            '    background-color: #f0f0ee;',
            '    border: 0, none;',
            '    height: 24px;',
            '    float: left;',
            '}',
            '.rtwiki-toolbar div {',
            '    padding: 0 10px;',
            '    height: 1.5em;',
            '    background: #f0f0ee;',
            '    line-height: 25px;',
            '    height: 24px;',
            '}',
            '.rtwiki-toolbar-leftside {',
            '    float: left;',
            '}',
            '.rtwiki-toolbar-rightside {',
            '    float: right;',
            '}',
            '.rtwiki-lag {',
            '    float: right;',
            '}',
            '</style>'
         ].join(''));
    };

    var uid = function () {
        return 'rtwiki-uid-' + String(Math.random()).substring(2);
    };

    // only used within updateUserList so far
    var decodeUser = function (all, one) {
        return decodeURIComponent(one);
    };

    var updateUserList = function (myUserName, listElement, userList, messages) {
        var meIdx = userList.indexOf(myUserName);
        if (meIdx === -1) {
            listElement.text(messages.disconnected);
            return;
        }
        var userMap = {};
        userMap[messages.myself] = 1;
        userList.splice(meIdx, 1);

        for (var i = 0; i < userList.length; i++) {
            var user;
            if (userList[i].indexOf('xwiki:XWiki.XWikiGuest') === 0) {
                if (userMap.Guests) {
                    user = messages.guests;
                } else {
                    user = messages.guest;
                }
            } else {
                user = userList[i].replace(/^.*-([^-]*)%2d[0-9]*$/, decodeUser);
            }
            userMap[user] = userMap[user] || 0;
            if (user === messages.guest && userMap[user] > 0) {
                userMap.Guests = userMap[user];
                delete userMap[user];
                user = messages.guests;
            }
            userMap[user]++;
        }
        var userListOut = [];
        for (var name in userMap) {
            if (userMap[name] > 1) {
                userListOut.push(userMap[name] + " " + name);
            } else {
                userListOut.push(name);
            }
        }
        if (userListOut.length > 1) {
            userListOut[userListOut.length-1] =
                messages.and + ' ' + userListOut[userListOut.length-1];
        }
        listElement.text(messages.editingWith + ' ' + userListOut.join(', '));
    };

    var createUserList = function (realtime, myUserName, container, messages) {
        var id = uid();
        $(container).prepend('<div class="rtwiki-userlist" id="'+id+'"></div>');
        var listElement = $('#'+id);
        return listElement;
    };

    var checkLag = function (realtime, lagElement, messages) {
        var lag = realtime.getLag();
        var lagSec = lag.lag/1000;
        var lagMsg = messages.lag + ' ';
        if (lag.waiting && lagSec > 1) {
            lagMsg += "?? " + Math.floor(lagSec);
        } else {
            lagMsg += lagSec;
        }
        lagElement.text(lagMsg);
    };

    var createLagElement = function (socket, realtime, container, messages) {
        var id = uid();
        $(container).append('<div class="rtwiki-lag" id="'+id+'"></div>');
        var lagElement = $('#'+id);
        var intr = setInterval(function () {
            checkLag(realtime, lagElement, messages);
        }, 3000);
        socket.onClose.push(function () { clearTimeout(intr); });
        return lagElement;
    };

    var createRealtimeToolbar = function (container) {
        var id = uid();
        $(container).prepend(
            '<div class="rtwiki-toolbar" id="' + id + '">' +
                '<div class="rtwiki-toolbar-leftside"></div>' +
                '<div class="rtwiki-toolbar-rightside"></div>' +
            '</div>'
        );
        return $('#'+id);
    };

    var now = function () { return (new Date()).getTime(); };

    var getFormToken = function () {
        return $('meta[name="form_token"]').attr('content');
    };

    var getDocumentSection = function (sectionNum, andThen) {
        debug("getting document section...");
        $.ajax({
            url: window.docediturl,
            type: "POST",
            async: true,
            dataType: 'text',
            data: {
                xpage: 'editwiki',
                section: ''+sectionNum
            },
            success: function (jqxhr) {
                var content = $(jqxhr).find('#content');
                if (!content || !content.length) {
                    andThen(new Error("could not find content"));
                } else {
                    andThen(undefined, content.text());
                }
            },
            error: function (jqxhr, err, cause) {
                andThen(new Error(err));
            }
        });
    };

    var getIndexOfDocumentSection = function (documentContent, sectionNum, andThen) {
        getDocumentSection(sectionNum, function (err, content) {
            if (err) {
                andThen(err);
                return;
            }
            // This is screwed up, XWiki generates the section by rendering the XDOM back to
            // XWiki2.0 syntax so it's not possible to find the actual location of a section.
            // See: http://jira.xwiki.org/browse/XWIKI-10430
            var idx = documentContent.indexOf(content);
            if (idx === -1) {
                content = content.split('\n')[0];
                idx = documentContent.indexOf(content);
            }
            if (idx === -1) {
                warn("Could not find section content..");
            } else if (idx !== documentContent.lastIndexOf(content)) {
                warn("Duplicate section content..");
            } else {
                andThen(undefined, idx);
                return;
            }
            andThen(undefined, 0);
        });
    };

    var seekToSection = function (textArea, andThen) {
        var sect = window.location.hash.match(/^#!([\W\w]*&)?section=([0-9]+)/);
        if (!sect || !sect[2]) {
            andThen();
            return;
        }
        var text = $(textArea).text();
        getIndexOfDocumentSection(text, Number(sect[2]), function (err, idx) {
            if (err) { andThen(err); return; }
            if (idx === 0) {
                warn("Attempted to seek to a section which could not be found");
            } else {
                var heightOne = $(textArea)[0].scrollHeight;
                $(textArea).text(text.substring(idx));
                var heightTwo = $(textArea)[0].scrollHeight;
                $(textArea).text(text);
                $(textArea).scrollTop(heightOne - heightTwo);
            }
            andThen();
        });
    };

    var saveDocument = function (textArea, language, andThen) {
        debug("saving document...");
        $.ajax({
            url: window.docsaveurl,
            type: "POST",
            async: true,
            dataType: 'text',
            data: {
                xredirect: '',
                content: $(textArea).val(),
                xeditaction: 'edit',
                comment: 'Auto-Saved by Realtime Session',
                action_saveandcontinue: 'Save & Continue',
                minorEdit: 1,
                ajax: true,
                form_token: getFormToken(),
                language: language
            },
            success: function () {
                andThen();
            },
            error: function (jqxhr, err, cause) {
                warn(err);
                // Don't callback, this way in case of error we will keep trying.
                //andThen();
            }
        });
    };

    /**
     * If we are editing a page which does not exist and creating it from a template
     * then we should not auto-save the document otherwise it will cause RTWIKI-16
     */
    var createPageMode = function () {
        return (window.location.href.indexOf('template=') !== -1);
    };

    var createSaver = function (socket, channel, myUserName, textArea, demoMode, language) {
        var timeOfLastSave = now();
        socket.onMessage.unshift(function (evt) {
            // get the content...
            var chanIdx = evt.data.indexOf(channel);
            var content = evt.data.substring(evt.data.indexOf(':[', chanIdx + channel.length)+1);

            // parse
            var json = JSON.parse(content);

            // not an isaved message
            if (json[0] !== MESSAGE_TYPE_ISAVED) { return; }

            timeOfLastSave = now();
            return false;
        });

        var lastSavedState = '';
        var to;
        var check = function () {
            if (to) { clearTimeout(to); }
            debug("createSaver.check");
            to = setTimeout(check, Math.random() * SAVE_DOC_CHECK_CYCLE);
            if (now() - timeOfLastSave < SAVE_DOC_TIME) { return; }
            var toSave = $(textArea).val();
            if (lastSavedState === toSave) { return; }
            if (demoMode) { return; }
            saveDocument(textArea, language, function () {
                debug("saved document");
                timeOfLastSave = now();
                lastSavedState = toSave;
                var saved = JSON.stringify([MESSAGE_TYPE_ISAVED, 0]);
                socket.send('1:x' +
                    myUserName.length + ':' + myUserName +
                    channel.length + ':' + channel +
                    saved.length + ':' + saved
                );
            });
        };
        check();
        socket.onClose.push(function () {
            clearTimeout(to);
        });
    };

    var isSocketDisconnected = function (socket, realtime) {
        return socket.readyState === socket.CLOSING ||
            socket.readyState === socket.CLOSED ||
            (realtime.getLag().waiting && realtime.getLag().lag > MAX_LAG_BEFORE_DISCONNECT);
    };

    var setAutosaveHiddenState = function (hidden) {
        var elem = $('#autosaveControl');
        if (hidden) {
            elem.hide();
        } else {
            elem.show();
        }
    };

    var startWebSocket = function (textArea,
                                   toolbarContainer,
                                   websocketUrl,
                                   userName,
                                   channel,
                                   messages,
                                   demoMode,
                                   language)
    {
        debug("Opening websocket");
        localStorage.removeItem(LOCALSTORAGE_DISALLOW);

        var toolbar = createRealtimeToolbar(toolbarContainer);
        var socket = new WebSocket(websocketUrl);
        socket.onClose = [];
        socket.onMessage = [];
        var initState = $(textArea).val();
        var realtime = socket.realtime = ChainPad.create(userName, 'x', channel, initState);
        // for debugging
        window.rtwiki_chainpad = realtime;

        // http://jira.xwiki.org/browse/RTWIKI-21
        var onbeforeunload = window.onbeforeunload || function () { };
        window.onbeforeunload = function (ev) {
            socket.intentionallyClosing = true;
            return onbeforeunload(ev);
        };

        var isErrorState = false;
        var checkSocket = function () {
            if (socket.intentionallyClosing || isErrorState) { return false; }
            if (isSocketDisconnected(socket, realtime)) {
                realtime.abort();
                socket.close();
                ErrorBox.show('disconnected');
                isErrorState = true;
                return true;
            }
            return false;
        };

        socket.onopen = function (evt) {

            var initializing = true;

            var userListElement = createUserList(realtime,
                                                 userName,
                                                 toolbar.find('.rtwiki-toolbar-leftside'),
                                                 messages);

            userListElement.text(messages.initializing);

            createLagElement(socket,
                             realtime,
                             toolbar.find('.rtwiki-toolbar-rightside'),
                             messages);

            setAutosaveHiddenState(true);

            createSaver(socket, channel, userName, textArea, demoMode, language);

            socket.onMessage.push(function (evt) {
                debug(evt.data);
                realtime.message(evt.data);
            });
            realtime.onMessage(function (message) { socket.send(message); });

            $(textArea).attr("disabled", "disabled");

            realtime.onUserListChange(function (userList) {
                if (initializing && userList.indexOf(userName) > -1) {
                    initializing = false;
                    $(textArea).val(realtime.getUserDoc());
                    textArea.attach($(textArea)[0], realtime);
                    $(textArea).removeAttr("disabled");
                }
                if (!initializing) {
                    updateUserList(userName, userListElement, userList, messages);
                }
            });


            debug("Bound websocket");
            realtime.start();
        };
        socket.onclose = function (evt) {
            for (var i = 0; i < socket.onClose.length; i++) {
                if (socket.onClose[i](evt) === false) { return; }
            }
        };
        socket.onmessage = function (evt) {
            for (var i = 0; i < socket.onMessage.length; i++) {
                if (socket.onMessage[i](evt) === false) { return; }
            }
        };
        socket.onerror = function (err) {
            warn(err);
            checkSocket(realtime);
        };

        var to = setInterval(function () {
            checkSocket(realtime);
        }, 500);
        socket.onClose.push(function () {
            clearTimeout(to);
            if (toolbar && typeof toolbar.remove === 'function') {
                toolbar.remove();
            } else {
                warn("toolbar.remove is not a function"); //why not?
            }
            setAutosaveHiddenState(false);
        });

        return socket;
    };

    var stopWebSocket = function (socket) {
        debug("Stopping websocket");
        socket.intentionallyClosing = true;
        if (!socket) { return; }
        if (socket.realtime) { socket.realtime.abort(); }
        socket.close();
    };

    var checkSectionEdit = function () {
        var href = window.location.href;
        if (href.indexOf('#') === -1) { href += '#!'; }
        var si = href.indexOf('section=');
        if (si === -1 || si > href.indexOf('#')) { return false; }
        var m = href.match(/([&]*section=[0-9]+)/)[1];
        href = href.replace(m, '');
        if (m[0] === '&') { m = m.substring(1); }
        href = href + '&' + m;
        window.location.href = href;
        return true;
    };

    var editor = function (websocketUrl, userName, messages, channel, demoMode, language) {
        var contentInner = $('#xwikieditcontentinner');
        var textArea = contentInner.find('#content');
        if (!textArea.length) {
            warn("WARNING: Could not find textarea to bind to");
            return;
        }

        if (createPageMode()) { return; }

        if (checkSectionEdit()) { return; }

        setStyle();

        var checked = (localStorage.getItem(LOCALSTORAGE_DISALLOW)) ? "" : 'checked="checked"';
        var allowRealtimeCbId = uid();
        $('#mainEditArea .buttons').append(
            '<div class="rtwiki-allow-outerdiv">' +
                '<label class="rtwiki-allow-label" for="' + allowRealtimeCbId + '">' +
                    '<input type="checkbox" class="rtwiki-allow" id="' + allowRealtimeCbId + '" ' +
                        checked + '" />' +
                    ' ' + messages.allowRealtime +
                '</label>' +
            '</div>'
        );

        var socket;
        var checkboxClick = function (checked) {
            if (checked || demoMode) {
                socket = startWebSocket(textArea,
                                        contentInner,
                                        websocketUrl,
                                        userName,
                                        channel,
                                        messages,
                                        demoMode,
                                        language);
            } else if (socket) {
                localStorage.setItem(LOCALSTORAGE_DISALLOW, 1);
                stopWebSocket(socket);
                socket = undefined;
            }
        };

        seekToSection(textArea, function (err) {
            if (err) { throw err; }
            $('#'+allowRealtimeCbId).click(function () { checkboxClick(this.checked); });
            checkboxClick(checked);
        });
    };

    var main = module.exports.main = function (websocketUrl,
                                               userName,
                                               messages,
                                               channel,
                                               demoMode,
                                               language)
    {

        if (!websocketUrl) {
            throw new Error("No WebSocket URL, please ensure Realtime Backend is installed.");
        }

        // Either we are in edit mode or the document is locked.
        // There is no cross-language way that the UI tells us the document is locked
        // but we can hunt for the force button.
        var forceLink = $('a[href$="&force=1"][href*="/edit/"]');

        var hasActiveRealtimeSession = function () {
            forceLink.text(messages.joinSession);
            forceLink.attr('href', forceLink.attr('href') + '&editor=wiki');
        };

        if (forceLink.length && !localStorage.getItem(LOCALSTORAGE_DISALLOW)) {
            // ok it's locked.
            var socket = new WebSocket(websocketUrl);
            socket.onopen = function (evt) {
                socket.onmessage = function (evt) {
                    debug("Message! " + evt.data);
                    var regMsgEnd = '3:[0]';
                    if (evt.data.indexOf(regMsgEnd) !== evt.data.length - regMsgEnd.length) {
                        // Not a register message
                    } else if (evt.data.indexOf(userName.length + ':' + userName) === 0) {
                        // It's us registering
                    } else {
                        // Someone has registered
                        debug("hasActiveRealtimeSession");
                        socket.close();
                        hasActiveRealtimeSession();
                    }
                };
                socket.send('1:x' + userName.length + ':' + userName +
                    channel.length + ':' + channel + '3:[0]');
                debug("Bound websocket");
            };
        } else if (window.XWiki.editor === 'wiki' || demoMode) {
            editor(websocketUrl, userName, messages, channel, demoMode, language);
        }
    };
  
    // CodeMirror/RTWiki
    // Trapping Keyboard Events
    var bindEvents = function (element, events, callback, unbind) {
        for (var i = 0; i < events.length; i++) {
            var e = events[i];
            if (element.addEventListener) {
                if (unbind) {
                    element.removeEventListener(e, callback, false);
                } else {
                    element.addEventListener(e, callback, false);
                }
            } else {
                if (unbind) {
                    element.detachEvent('on' + e, callback);
                } else {
                    element.attachEvent('on' + e, callback);
                }
            }
        }
    };

    var bindAllEvents = function (cmDiv, onEvent, unbind)
    {
        bindEvents(cmDiv,
                   ['textInput', 'keydown', 'keyup', 'select', 'cut', 'paste', 'mousedown','mouseup','click'],
                   onEvent,
                   unbind);
    };
  
    var transformCursorCMRemove = function(text, cursor, pos, length) {
      var newCursor = cursor;
      var textLines = text.substr(0, pos).split("\n");
      var removedTextLineNumber = textLines.length-1;
      var removedTextColumnIndex = textLines[textLines.length-1].length;
      var removedLines = text.substr(pos, length).split("\n").length - 1;
      if(cursor.line > (removedTextLineNumber + removedLines)) {
        newCursor.line -= removedLines;
      }
      else if(removedLines > 0 && cursor.line === (removedTextLineNumber+removedLines)) {
        var lastLineCharsRemoved = text.substr(pos, length).split("\n")[removedLines].length;
        if(cursor.ch >= lastLineCharsRemoved) {
          newCursor.line = removedTextLineNumber;
          newCursor.ch = removedTextColumnIndex + cursor.ch - lastLineCharsRemoved;
        }
        else {
          newCursor.line -= removedLines;
          newCursor.ch = removedTextColumnIndex;
        }
      }
      else if(cursor.line === removedTextLineNumber && cursor.ch > removedTextLineNumber) {
        newCursor.ch -= Math.min(length, cursor.ch-removedTextLineNumber);
      }
      return newCursor;
    };
    var transformCursorCMInsert = function(oldtext, cursor, pos, text) {
      var newCursor = cursor;
      var textLines = oldtext.substr(0, pos).split("\n");
      var addedTextLineNumber = textLines.length-1;
      var addedTextColumnIndex = textLines[textLines.length-1].length;
      var addedLines = text.split("\n").length - 1;
      if(cursor.line > addedTextLineNumber) {
        newCursor.line += addedLines;
      }
      else if(cursor.line === addedTextLineNumber && cursor.ch > addedTextColumnIndex) {
        newCursor.line += addedLines;
        if(addedLines > 0) {
          newCursor.ch = newCursor.ch - addedTextColumnIndex + text.split("\n")[addedLines].length;
        }
        else {
          newCursor.ch += text.split("\n")[addedLines].length;
        }
      }
      return newCursor;
    };
  
    var startWebSocketCM = function (windowCM,
                                   websocketUrl,
                                   userName,
                                   channel,
                                   messages,
                                   cryptKey)
    {
        debug("Opening websocket");
        var textArea = windowCM.document.getElementById('editor1');
        var cmDiv = windowCM.document.getElementsByClassName('CodeMirror')[0];
        var cmEditor = cmDiv.CodeMirror;
        var onEvent = function () { };
        var socket = new WebSocket(websocketUrl);
        socket.onClose = [];
        socket.onMessage = [];
        var initState = $(textArea).val();
        var realtime = socket.realtime = ChainPad.create(userName, 'x', channel, initState);
        var toolbar = realtime.toolbar = Toolbar.create(windowCM.$('#cme_toolbox'), userName, realtime);
        // for debugging
        window.rtwiki_chainpad = realtime;

        // http://jira.xwiki.org/browse/RTWIKI-21
        var onbeforeunload = window.onbeforeunload || function () { };
        window.onbeforeunload = function (ev) {
            socket.intentionallyClosing = true;
            return onbeforeunload(ev);
        };
        var isErrorState = false;
        var recoverableErrorCount = 0;
        var error = function (recoverable, err) {
            console.log(new Error().stack);
            console.log('error: ' + err.stack);
            if (recoverable && recoverableErrorCount++ < MAX_RECOVERABLE_ERRORS) { return; }
            var realtime = socket.realtime;
            var docHtml = $(textArea).val();
            isErrorState = true;

            // FIXME pull this in from more mainline version
            //handleError(socket, realtime, err, docHtml, allMessages);
        };
        var attempt = function (func) {
            return function () {
                var e;
                try { return func.apply(func, arguments); } catch (ee) { e = ee; }
                if (e) {
                    console.log(e.stack);
                    error(true, e);
                }
            };
        };
      
        var checkSocket = function () {
            if (socket.intentionallyClosing || isErrorState) { return false; }
            if (isSocketDisconnected(socket, realtime)) {
                realtime.abort();
                realtime.toolbar.failed();
                socket.close();
                ErrorBox.show('disconnected');
                isErrorState = true;
                return true;
            }
            return false;
        };
        
        socket.onopen = function (evt) {

            var initializing = true;

            var userListElement = createUserList(realtime,
                                                 userName,
                                                 [],
                                                 messages);
            userListElement.text(messages.initializing);
            createLagElement(socket,
                             realtime,
                             [],
                             messages);

            setAutosaveHiddenState(true);
            onEvent = function () {
                if (isErrorState) { return; }
                if (initializing) { return; }
                var oldDocText = realtime.getUserDoc();
                var docText = $(textArea).val();
                var op = attempt(Otaml.makeTextOperation)(oldDocText, docText);

                if (!op) { return; }
                if (op.toRemove > 0) {
                    attempt(realtime.remove)(op.offset, op.toRemove);
                }
                if (op.toInsert.length > 0) {
                    attempt(realtime.insert)(op.offset, op.toInsert);
                }

                if (realtime.getUserDoc() !== docText) {
                    error(false, 'realtime.getUserDoc() !== docText');
                }
            };
            
            socket.onMessage.push(function (evt) {
                debug(evt.data);
                var message = Crypto.decrypt(evt.data, cryptKey);
                realtime.message(message);
            });
            realtime.onMessage(function (message) { message = Crypto.encrypt(message, cryptKey);socket.send(message); });
            
            var userDocBeforePatch;
            var incomingPatch = function () {
                if (isErrorState || initializing) { return; }
                var textAreaVal = $(textArea).val();
                userDocBeforePatch = userDocBeforePatch || textAreaVal;
                if (userDocBeforePatch !== textAreaVal) {
                  //error(false, "userDocBeforePatch !== textAreaVal");
                }
                var op = attempt(Otaml.makeTextOperation)(userDocBeforePatch, realtime.getUserDoc());

                if (typeof op === 'undefined') {
                    warn("TypeError: op is undefined");
                    return;
                } 

                var oldValue = textAreaVal;
                var newValue = realtime.getUserDoc();
                // Fix cursor and/or selection
                var oldCursor = cmEditor.getCursor();
                var oldCursorCMStart = cmEditor.getCursor('from');
                var oldCursorCMEnd = cmEditor.getCursor('to');
                var newCursor;
                var newSelection;
                if(oldCursorCMStart !== oldCursorCMEnd) { // Selection
                    if (op.toRemove > 0) {
                        newSelection = [transformCursorCMRemove(oldValue, oldCursorCMStart, op.offset, op.toRemove), transformCursorCMRemove(oldValue, oldCursorCMEnd, op.offset, op.toRemove)];
                    }
                    if (op.toInsert.length > 0) {
                        newSelection = [transformCursorCMInsert(oldValue, oldCursorCMStart, op.offset, op.toInsert), transformCursorCMInsert(oldValue, oldCursorCMEnd, op.offset, op.toInsert)];
                    }
                }
                else { // Cursor
                    if (op.toRemove > 0) {
                        newCursor = transformCursorCMRemove(oldValue, oldCursor, op.offset, op.toRemove);
                    }
                    if (op.toInsert.length > 0) {
                        newCursor = transformCursorCMInsert(oldValue, oldCursor, op.offset, op.toInsert);
                    }
                }
                $(textArea).val(newValue);
                cmEditor.setValue(newValue);
                if(newCursor) {
                  cmEditor.setCursor(newCursor);
                }
                else {
                  cmEditor.setSelection(newSelection[0], newSelection[1]);
                }
            };
            realtime.onPatch(incomingPatch);
            realtime.onUserListChange(function (userList) {
                if (initializing && userList.indexOf(userName) > -1) {
                    initializing = false;
                    incomingPatch();
                }
                if (!initializing) {
                    updateUserList(userName, userListElement, userList, messages);
                }
            });
            debug("Bound websocket");
            bindAllEvents(cmDiv, onEvent, false);
            setInterval(function () {
                if (isErrorState || checkSocket()) {
                    toolbar.reconnecting();
                }
            }, 200);
            realtime.start();
            toolbar.connected();
        };
        socket.onclose = function (evt) {
            for (var i = 0; i < socket.onClose.length; i++) {
                if (socket.onClose[i](evt) === false) { return; }
            }
        };
        socket.onmessage = function (evt) {
            for (var i = 0; i < socket.onMessage.length; i++) {
                if (socket.onMessage[i](evt) === false) { return; }
            }
        };
        socket.onerror = function (err) {
            warn(err);
            checkSocket(realtime);
        };

        var to = setInterval(function () {
            checkSocket(realtime);
        }, 500);
        socket.onClose.push(function () {
            clearTimeout(to);
            if (toolbar && typeof toolbar.remove === 'function') {
                toolbar.remove();
            } else {
                warn("toolbar.remove is not a function"); //why not?
            }
            setAutosaveHiddenState(false);
        });
        socket.onEvent = function(){
          onEvent();
        };
        return socket;
    };
    
    var cmEditor = function (cmWindow, websocketUrl, userName, messages, channel, cryptkey) {
        var cmTextarea = $(cmWindow.document.getElementById('editor1'));
        if (!cmTextarea.length) {
            warn("WARNING: Could not find textarea to bind to");
            return;
        }
        var socket = startWebSocketCM(cmWindow,
                                websocketUrl,
                                userName,
                                channel,
                                messages,
                                cryptkey);
        return {
            onEvent: function() {
              socket.onEvent();
            }
        };
    };
  
    var start = module.exports.start = function (window, websocketUrl,
                                               userName,
                                               channel,
                                               cryptkey)
    {
        if (!websocketUrl) {
            throw new Error("No WebSocket URL, please ensure Realtime Backend is installed.");
        }
        var cme = cmEditor(window, websocketUrl, userName, Messages, channel, cryptkey);
        return {
            onEvent: function () { 
              cme.onEvent();
            }
        };
    };

    return module.exports;
});