Proyectos de Subversion Moodle

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle 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 General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Controls the conversation page in the message drawer.

 *

 * This function handles all of the user actions that the user can take

 * when interacting with the conversation page.

 *

 * It maintains a view state which is a data representation of the view

 * and only operates on that data.

 *

 * The view state is immutable and should never be modified directly. Instead

 * all changes to the view state should be done using the StateManager which

 * will generate a new version of the view state with the requested changes.

 *

 * After any changes to the view state the module will call the render function

 * to ask the renderer to update the UI.

 *

 * General rules for this module:

 * 1.) Never modify viewState directly. All changes should be via the StateManager.

 * 2.) Call render() with the new state when you want to update the UI

 * 3.) Never modify the UI directly in this module. This module is only concerned

 *     with the data in the view state.

 *

 * The general flow for a user interaction will be something like:

 * User interaction: User clicks "confirm block" button to block the other user

 *      1.) This module is hears the click

 *      2.) This module sends a request to the server to block the user

 *      3.) The server responds with the new user profile

 *      4.) This module generates a new state using the StateManager with the updated

 *          user profile.

 *      5.) This module asks the Patcher to generate a patch from the current state and

 *          the newly generated state. This patch tells the renderer what has changed

 *          between the states.

 *      6.) This module gives the Renderer the generated patch. The renderer updates

 *          the UI with changes according to the patch.

 *

 * @module     core_message/message_drawer_view_conversation

 * @copyright  2018 Ryan Wyllie <ryan@moodle.com>

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

define(

[

    'jquery',

    'core/auto_rows',

    'core/backoff_timer',

    'core/custom_interaction_events',

    'core/notification',

    'core/pending',

    'core/pubsub',

    'core/str',

    'core_message/message_repository',

    'core_message/message_drawer_events',

    'core_message/message_drawer_view_conversation_constants',

    'core_message/message_drawer_view_conversation_patcher',

    'core_message/message_drawer_view_conversation_renderer',

    'core_message/message_drawer_view_conversation_state_manager',

    'core_message/message_drawer_router',

    'core_message/message_drawer_routes',

    'core/emoji/auto_complete',

    'core/emoji/picker'

],

function(

    $,

    AutoRows,

    BackOffTimer,

    CustomEvents,

    Notification,

    Pending,

    PubSub,

    Str,

    Repository,

    MessageDrawerEvents,

    Constants,

    Patcher,

    Renderer,

    StateManager,

    MessageDrawerRouter,

    MessageDrawerRoutes,

    initialiseEmojiAutoComplete,

    initialiseEmojiPicker

) {

    // Contains a cache of all view states that have been loaded so far

    // which saves us having to reload stuff with network requests when

    // switching between conversations.

    var stateCache = {};

    // The current data representation of the view.

    var viewState = null;

    var loadedAllMessages = false;

    var messagesOffset = 0;

    var newMessagesPollTimer = null;

    var isRendering = false;

    var renderBuffer = [];

    // If the UI is currently resetting.

    var isResetting = true;

    // If the UI is currently sending a message.

    var isSendingMessage = false;

    // If the UI is currently deleting a conversation.

    var isDeletingConversationContent = false;

    // A buffer of messages to send.

    var sendMessageBuffer = [];

    // These functions which will be generated when this module is

    // first called. See generateRenderFunction for details.

    var render = null;

    // The list of renderers that have been registered to render

    // this conversation. See generateRenderFunction for details.

    var renderers = [];

    var NEWEST_FIRST = Constants.NEWEST_MESSAGES_FIRST;

    var LOAD_MESSAGE_LIMIT = Constants.LOAD_MESSAGE_LIMIT;

    var MILLISECONDS_IN_SEC = Constants.MILLISECONDS_IN_SEC;

    var SELECTORS = Constants.SELECTORS;

    var CONVERSATION_TYPES = Constants.CONVERSATION_TYPES;

    /**

     * Get the other user userid.

     *

     * @return {Number} Userid.

     */

    var getOtherUserId = function() {

        if (!viewState || viewState.type == CONVERSATION_TYPES.PUBLIC) {

            return null;

        }

        var loggedInUserId = viewState.loggedInUserId;

        if (viewState.type == CONVERSATION_TYPES.SELF) {

            // It's a self-conversation, so the other user is the one logged in.

            return loggedInUserId;

        }

        var otherUserIds = Object.keys(viewState.members).filter(function(userId) {

            return loggedInUserId != userId;

        });

        return otherUserIds.length ? otherUserIds[0] : null;

    };

    /**

     * Search the cache to see if we've already loaded a private conversation

     * with the given user id.

     *

     * @param {Number} userId The id of the other user.

     * @return {Number|null} Conversation id.

     */

    var getCachedPrivateConversationIdFromUserId = function(userId) {

        return Object.keys(stateCache).reduce(function(carry, id) {

            if (!carry) {

                var state = stateCache[id].state;

                if (state.type != CONVERSATION_TYPES.PUBLIC) {

                    if (userId in state.members) {

                        // We've found a cached conversation for this user!

                        carry = state.id;

                    }

                }

            }

            return carry;

        }, null);

    };

    /**

     * Get profile info for logged in user.

     *

     * @param {Object} body Conversation body container element.

     * @return {Object}

     */

    var getLoggedInUserProfile = function(body) {

        return {

            id: parseInt(body.attr('data-user-id'), 10),

            fullname: null,

            profileimageurl: null,

            profileimageurlsmall: null,

            isonline:  null,

            showonlinestatus: null,

            isblocked: null,

            iscontact: null,

            isdeleted: null,

            canmessage: null,

            canmessageevenifblocked: null,

            requirescontact: null,

            contactrequests: [],

            cancreatecontact: null,

        };

    };

    /**

     * Get the messages offset value to load more messages.

     *

     * @return {Number}

     */

    var getMessagesOffset = function() {

        return messagesOffset;

    };

    /**

     * Set the messages offset value for loading more messages.

     *

     * @param {Number} value The offset value

     */

    var setMessagesOffset = function(value) {

        messagesOffset = value;

        stateCache[viewState.id].messagesOffset = value;

    };

    /**

     * Check if all messages have been loaded.

     *

     * @return {Bool}

     */

    var hasLoadedAllMessages = function() {

        return loadedAllMessages;

    };

    /**

     * Set whether all messages have been loaded or not.

     *

     * @param {Bool} value If all messages have been loaded.

     */

    var setLoadedAllMessages = function(value) {

        loadedAllMessages = value;

        stateCache[viewState.id].loadedAllMessages = value;

    };

    /**

     * Get the messages container element.

     *

     * @param  {Object} body Conversation body container element.

     * @return {Object} The messages container element.

     */

    var getMessagesContainer = function(body) {

        return body.find(SELECTORS.MESSAGES_CONTAINER);

    };

    /**

     * Reformat the conversation for an event payload.

     *

     * @param  {Object} state The view state.

     * @return {Object} New formatted conversation.

     */

    var formatConversationForEvent = function(state) {

        return {

            id: state.id,

            name: state.name,

            subname: state.subname,

            imageUrl: state.imageUrl,

            isFavourite: state.isFavourite,

            isMuted: state.isMuted,

            type: state.type,

            totalMemberCount: state.totalMemberCount,

            loggedInUserId: state.loggedInUserId,

            messages: state.messages.map(function(message) {

                return $.extend({}, message);

            }),

            members: Object.keys(state.members).map(function(id) {

                var formattedMember = $.extend({}, state.members[id]);

                formattedMember.contactrequests = state.members[id].contactrequests.map(function(request) {

                    return $.extend({}, request);

                });

                return formattedMember;

            })

        };

    };

    /**

     * Load up an empty private conversation between the logged in user and the

     * other user. Sets all of the conversation details based on the other user.

     *

     * A conversation isn't created until the user sends the first message.

     *

     * @param  {Object} loggedInUserProfile The logged in user profile.

     * @param  {Number} otherUserId The other user id.

     * @return {Object} Profile returned from repository.

     */

    var loadEmptyPrivateConversation = function(loggedInUserProfile, otherUserId) {

        var loggedInUserId = loggedInUserProfile.id;

        // If the other user id is the same as the logged in user then this is a self

        // conversation.

        var conversationType = loggedInUserId == otherUserId ? CONVERSATION_TYPES.SELF : CONVERSATION_TYPES.PRIVATE;

        var newState = StateManager.setLoadingMembers(viewState, true);

        newState = StateManager.setLoadingMessages(newState, true);

        render(newState);

        return Repository.getMemberInfo(loggedInUserId, [otherUserId], true, true)

            .then(function(profiles) {

                if (profiles.length) {

                    return profiles[0];

                } else {

                    throw new Error('Unable to load other user profile');

                }

            })

            .then(function(profile) {

                // If the conversation is a self conversation then the profile loaded is the

                // logged in user so only add that to the members array.

                var members = conversationType == CONVERSATION_TYPES.SELF ? [profile] : [profile, loggedInUserProfile];

                var newState = StateManager.addMembers(viewState, members);

                newState = StateManager.setLoadingMembers(newState, false);

                newState = StateManager.setLoadingMessages(newState, false);

                newState = StateManager.setName(newState, profile.fullname);

                newState = StateManager.setType(newState, conversationType);

                newState = StateManager.setImageUrl(newState, profile.profileimageurl);

                newState = StateManager.setTotalMemberCount(newState, members.length);

                render(newState);

                return profile;

            })

            .catch(function(error) {

                var newState = StateManager.setLoadingMembers(viewState, false);

                render(newState);

                Notification.exception(error);

            });

    };

    /**

     * Create a new state from a conversation object.

     *

     * @param {Object} conversation The conversation object.

     * @param {Number} loggedInUserId The logged in user id.

     * @return {Object} new state.

     */

    var updateStateFromConversation = function(conversation, loggedInUserId) {

        var otherUser = null;

        if (conversation.type == CONVERSATION_TYPES.PRIVATE) {

            // For private conversations, remove current logged in user from the members list to get the other user.

            var otherUsers = conversation.members.filter(function(member) {

                return member.id != loggedInUserId;

            });

            otherUser = otherUsers.length ? otherUsers[0] : null;

        } else if (conversation.type == CONVERSATION_TYPES.SELF) {

            // Self-conversations have only one member.

            otherUser = conversation.members[0];

        }

        var name = conversation.name;

        var imageUrl = conversation.imageurl;

        if (conversation.type != CONVERSATION_TYPES.PUBLIC) {

            name = name || otherUser ? otherUser.fullname : '';

            imageUrl = imageUrl || otherUser ? otherUser.profileimageurl : '';

        }

        var newState = StateManager.addMembers(viewState, conversation.members);

        newState = StateManager.setName(newState, name);

        newState = StateManager.setSubname(newState, conversation.subname);

        newState = StateManager.setType(newState, conversation.type);

        newState = StateManager.setImageUrl(newState, imageUrl);

        newState = StateManager.setTotalMemberCount(newState, conversation.membercount);

        newState = StateManager.setIsFavourite(newState, conversation.isfavourite);

        newState = StateManager.setIsMuted(newState, conversation.ismuted);

        newState = StateManager.addMessages(newState, conversation.messages);

        newState = StateManager.setCanDeleteMessagesForAllUsers(newState, conversation.candeletemessagesforallusers);

        return newState;

    };

    /**

     * Get the details for a conversation from the conversation id.

     *

     * @param  {Number} conversationId The conversation id.

     * @param  {Object} loggedInUserProfile The logged in user profile.

     * @param  {Number} messageLimit The number of messages to include.

     * @param  {Number} messageOffset The number of messages to skip.

     * @param  {Bool} newestFirst Order messages newest first.

     * @return {Object} Promise resolved when loaded.

     */

    var loadNewConversation = function(

        conversationId,

        loggedInUserProfile,

        messageLimit,

        messageOffset,

        newestFirst

    ) {

        var loggedInUserId = loggedInUserProfile.id;

        var newState = StateManager.setLoadingMembers(viewState, true);

        newState = StateManager.setLoadingMessages(newState, true);

        render(newState);

        return Repository.getConversation(

            loggedInUserId,

            conversationId,

            true,

            true,

            0,

            0,

            messageLimit + 1,

            messageOffset,

            newestFirst

        )

            .then(function(conversation) {

                if (conversation.messages.length > messageLimit) {

                    conversation.messages = conversation.messages.slice(1);

                } else {

                    setLoadedAllMessages(true);

                }

                setMessagesOffset(messageOffset + messageLimit);

                return conversation;

            })

            .then(function(conversation) {

                var hasLoggedInUser = conversation.members.filter(function(member) {

                    return member.id == loggedInUserProfile.id;

                });

                if (hasLoggedInUser.length < 1) {

                    conversation.members = conversation.members.concat([loggedInUserProfile]);

                }

                var newState = updateStateFromConversation(conversation, loggedInUserProfile.id);

                newState = StateManager.setLoadingMembers(newState, false);

                newState = StateManager.setLoadingMessages(newState, false);

                return render(newState)

                    .then(function() {

                        return conversation;

                    });

            })

            .then(function() {

                return markConversationAsRead(conversationId);

            })

            .catch(function(error) {

                var newState = StateManager.setLoadingMembers(viewState, false);

                newState = StateManager.setLoadingMessages(newState, false);

                render(newState);

                Notification.exception(error);

            });

    };

    /**

     * Get the details for a conversation from and existing conversation object.

     *

     * @param  {Object} conversation The conversation object.

     * @param  {Object} loggedInUserProfile The logged in user profile.

     * @param  {Number} messageLimit The number of messages to include.

     * @param  {Bool} newestFirst Order messages newest first.

     * @return {Object} Promise resolved when loaded.

     */

    var loadExistingConversation = function(

        conversation,

        loggedInUserProfile,

        messageLimit,

        newestFirst

    ) {

        var hasLoggedInUser = conversation.members.filter(function(member) {

            return member.id == loggedInUserProfile.id;

        });

        if (hasLoggedInUser.length < 1) {

            conversation.members = conversation.members.concat([loggedInUserProfile]);

        }

        var messageCount = conversation.messages.length;

        var hasLoadedEnoughMessages = messageCount >= messageLimit;

        var newState = updateStateFromConversation(conversation, loggedInUserProfile.id);

        newState = StateManager.setLoadingMembers(newState, false);

        newState = StateManager.setLoadingMessages(newState, !hasLoadedEnoughMessages);

        var renderPromise = render(newState);

        return renderPromise.then(function() {

                if (!hasLoadedEnoughMessages) {

                    // We haven't got enough messages so let's load some more.

                    return loadMessages(conversation.id, messageLimit, messageCount, newestFirst, []);

                } else {

                    // We've got enough messages. No need to load any more for now.

                    return {messages: conversation.messages};

                }

            })

            .then(function() {

                var messages = viewState.messages;

                // Update the offset to reflect the number of messages we've loaded.

                setMessagesOffset(messages.length);

                markConversationAsRead(viewState.id);

                return messages;

            })

            .catch(Notification.exception);

    };

    /**

     * Load messages for this conversation and pass them to the renderer.

     *

     * @param  {Number} conversationId Conversation id.

     * @param  {Number} limit Number of messages to load.

     * @param  {Number} offset Get messages from offset.

     * @param  {Bool} newestFirst Get newest messages first.

     * @param  {Array} ignoreList Ignore any messages with ids in this list.

     * @param  {Number|null} timeFrom Only get messages from this time onwards.

     * @return {Promise} renderer promise.

     */

    var loadMessages = function(conversationId, limit, offset, newestFirst, ignoreList, timeFrom) {

        return Repository.getMessages(

                viewState.loggedInUserId,

                conversationId,

                limit ? limit + 1 : limit,

                offset,

                newestFirst,

                timeFrom

            )

            .then(function(result) {

                // Prevent older requests from contaminating the current view.

                if (result.id != viewState.id) {

                    result.messages = [];

                    // Purge old conversation cache to prevent messages lose.

                    if (result.id in stateCache) {

                        delete stateCache[result.id];

                    }

                }

                return result;

            })

            .then(function(result) {

                if (result.messages.length && ignoreList.length) {

                    result.messages = result.messages.filter(function(message) {

                        // Skip any messages in our ignore list.

                        return ignoreList.indexOf(parseInt(message.id, 10)) < 0;

                    });

                }

                return result;

            })

            .then(function(result) {

                if (!limit) {

                    return result;

                } else if (result.messages.length > limit) {

                    // Ignore the last result which was just to test if there are more

                    // to load.

                    result.messages = result.messages.slice(0, -1);

                } else {

                    setLoadedAllMessages(true);

                }

                return result;

            })

            .then(function(result) {

                var membersToAdd = result.members.filter(function(member) {

                    return !(member.id in viewState.members);

                });

                var newState = StateManager.addMembers(viewState, membersToAdd);

                newState = StateManager.addMessages(newState, result.messages);

                newState = StateManager.setLoadingMessages(newState, false);

                return render(newState)

                    .then(function() {

                        return result;

                    });

            })

            .catch(function(error) {

                var newState = StateManager.setLoadingMessages(viewState, false);

                render(newState);

                // Re-throw the error for other error handlers.

                throw error;

            });

    };

    /**

     * Create a callback function for getting new messages for this conversation.

     *

     * @param  {Number} conversationId Conversation id.

     * @param  {Bool} newestFirst Show newest messages first

     * @return {Function} Callback function that returns a renderer promise.

     */

    var getLoadNewMessagesCallback = function(conversationId, newestFirst) {

        return function() {

            var messages = viewState.messages;

            var mostRecentMessage = messages.length ? messages[messages.length - 1] : null;

            var lastTimeCreated = mostRecentMessage ? mostRecentMessage.timeCreated : null;

            if (lastTimeCreated && !isResetting && !isSendingMessage && !isDeletingConversationContent) {

                // There may be multiple messages with the same time created value since

                // the accuracy is only down to the second. The server will include these

                // messages in the result (since it does a >= comparison on time from) so

                // we need to filter them back out of the result so that we're left only

                // with the new messages.

                var ignoreMessageIds = [];

                for (var i = messages.length - 1; i >= 0; i--) {

                    var message = messages[i];

                    if (message.timeCreated === lastTimeCreated) {

                        ignoreMessageIds.push(message.id);

                    } else {

                        // Since the messages are ordered in ascending order of time created

                        // we can break as soon as we hit a message with a different time created

                        // because we know all other messages will have lower values.

                        break;

                    }

                }

                return loadMessages(

                        conversationId,

                        0,

                        0,

                        newestFirst,

                        ignoreMessageIds,

                        lastTimeCreated

                    )

                    .then(function(result) {

                        if (result.messages.length) {

                            // If we found some results then restart the polling timer

                            // because the other user might be sending messages.

                            newMessagesPollTimer.restart();

                            // We've also got a new last message so publish that for other

                            // components to update.

                            var conversation = formatConversationForEvent(viewState);

                            PubSub.publish(MessageDrawerEvents.CONVERSATION_NEW_LAST_MESSAGE, conversation);

                            return markConversationAsRead(conversationId);

                        } else {

                            return result;

                        }

                    });

            }

            return $.Deferred().resolve().promise();

        };

    };

    /**

     * Mark a conversation as read.

     *

     * @param  {Number} conversationId The conversation id.

     * @return {Promise} The renderer promise.

     */

    var markConversationAsRead = function(conversationId) {

        var loggedInUserId = viewState.loggedInUserId;

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:markConversationAsRead');

        return Repository.markAllConversationMessagesAsRead(loggedInUserId, conversationId)

            .then(function() {

                var newState = StateManager.markMessagesAsRead(viewState, viewState.messages);

                PubSub.publish(MessageDrawerEvents.CONVERSATION_READ, conversationId);

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Tell the statemanager there is request to block a user and run the renderer

     * to show the block user dialogue.

     *

     * @param {Number} userId User id.

     */

    var requestBlockUser = function(userId) {

        cancelRequest(userId);

        var newState = StateManager.addPendingBlockUsersById(viewState, [userId]);

        render(newState);

    };

    /**

     * Send the repository a request to block a user, update the statemanager and publish

     * a contact has been blocked.

     *

     * @param  {Number} userId User id of user to block.

     * @return {Promise} Renderer promise.

     */

    var blockUser = function(userId) {

        var newState = StateManager.setLoadingConfirmAction(viewState, true);

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:blockUser');

        render(newState);

        return Repository.blockUser(viewState.loggedInUserId, userId)

            .then(function(profile) {

                var newState = StateManager.addMembers(viewState, [profile]);

                newState = StateManager.removePendingBlockUsersById(newState, [userId]);

                newState = StateManager.setLoadingConfirmAction(newState, false);

                PubSub.publish(MessageDrawerEvents.CONTACT_BLOCKED, userId);

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Tell the statemanager there is a request to unblock a user and run the renderer

     * to show the unblock user dialogue.

     *

     * @param {Number} userId User id of user to unblock.

     */

    var requestUnblockUser = function(userId) {

        cancelRequest(userId);

        var newState = StateManager.addPendingUnblockUsersById(viewState, [userId]);

        render(newState);

    };

    /**

     * Send the repository a request to unblock a user, update the statemanager and publish

     * a contact has been unblocked.

     *

     * @param  {Number} userId User id of user to unblock.

     * @return {Promise} Renderer promise.

     */

    var unblockUser = function(userId) {

        var newState = StateManager.setLoadingConfirmAction(viewState, true);

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:unblockUser');

        render(newState);

        return Repository.unblockUser(viewState.loggedInUserId, userId)

            .then(function(profile) {

                var newState = StateManager.addMembers(viewState, [profile]);

                newState = StateManager.removePendingUnblockUsersById(newState, [userId]);

                newState = StateManager.setLoadingConfirmAction(newState, false);

                PubSub.publish(MessageDrawerEvents.CONTACT_UNBLOCKED, userId);

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Tell the statemanager there is a request to remove a user from the contact list

     * and run the renderer to show the remove user from contacts dialogue.

     *

     * @param {Number} userId User id of user to remove from contacts.

     */

    var requestRemoveContact = function(userId) {

        cancelRequest(userId);

        var newState = StateManager.addPendingRemoveContactsById(viewState, [userId]);

        render(newState);

    };

    /**

     * Send the repository a request to remove a user from the contacts list. update the statemanager

     * and publish a contact has been removed.

     *

     * @param  {Number} userId User id of user to remove from contacts.

     * @return {Promise} Renderer promise.

     */

    var removeContact = function(userId) {

        var newState = StateManager.setLoadingConfirmAction(viewState, true);

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:removeContact');

        render(newState);

        return Repository.deleteContacts(viewState.loggedInUserId, [userId])

            .then(function(profiles) {

                var newState = StateManager.addMembers(viewState, profiles);

                newState = StateManager.removePendingRemoveContactsById(newState, [userId]);

                newState = StateManager.setLoadingConfirmAction(newState, false);

                PubSub.publish(MessageDrawerEvents.CONTACT_REMOVED, userId);

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Tell the statemanager there is a request to add a user to the contact list

     * and run the renderer to show the add user to contacts dialogue.

     *

     * @param {Number} userId User id of user to add to contacts.

     */

    var requestAddContact = function(userId) {

        cancelRequest(userId);

        var newState = StateManager.addPendingAddContactsById(viewState, [userId]);

        render(newState);

    };

    /**

     * Send the repository a request to add a user to the contacts list. update the statemanager

     * and publish a contact has been added.

     *

     * @param  {Number} userId User id of user to add to contacts.

     * @return {Promise} Renderer promise.

     */

    var addContact = function(userId) {

        var newState = StateManager.setLoadingConfirmAction(viewState, true);

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:addContactRequests');

        render(newState);

        return Repository.createContactRequest(viewState.loggedInUserId, userId)

            .then(function(response) {

                if (!response.request) {

                    throw new Error(response.warnings[0].message);

                }

                return response.request;

            })

            .then(function(request) {

                var newState = StateManager.removePendingAddContactsById(viewState, [userId]);

                newState = StateManager.addContactRequests(newState, [request]);

                newState = StateManager.setLoadingConfirmAction(newState, false);

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Set the current conversation as a favourite conversation.

     *

     * @return {Promise} Renderer promise.

     */

    var setFavourite = function() {

        var userId = viewState.loggedInUserId;

        var conversationId = viewState.id;

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:setFavourite');

        return Repository.setFavouriteConversations(userId, [conversationId])

            .then(function() {

                var newState = StateManager.setIsFavourite(viewState, true);

                return render(newState);

            })

            .then(function() {

                return PubSub.publish(

                    MessageDrawerEvents.CONVERSATION_SET_FAVOURITE,

                    formatConversationForEvent(viewState)

                );

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Unset the current conversation as a favourite conversation.

     *

     * @return {Promise} Renderer promise.

     */

    var unsetFavourite = function() {

        var userId = viewState.loggedInUserId;

        var conversationId = viewState.id;

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:unsetFavourite');

        return Repository.unsetFavouriteConversations(userId, [conversationId])

            .then(function() {

                var newState = StateManager.setIsFavourite(viewState, false);

                return render(newState);

            })

            .then(function() {

                return PubSub.publish(

                    MessageDrawerEvents.CONVERSATION_UNSET_FAVOURITE,

                    formatConversationForEvent(viewState)

                );

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Set the current conversation as a muted conversation.

     *

     * @return {Promise} Renderer promise.

     */

    var setMuted = function() {

        var userId = viewState.loggedInUserId;

        var conversationId = viewState.id;

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:markConversationAsRead');

        return Repository.setMutedConversations(userId, [conversationId])

            .then(function() {

                var newState = StateManager.setIsMuted(viewState, true);

                return render(newState);

            })

            .then(function() {

                return PubSub.publish(

                    MessageDrawerEvents.CONVERSATION_SET_MUTED,

                    formatConversationForEvent(viewState)

                );

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            });

    };

    /**

     * Unset the current conversation as a muted conversation.

     *

     * @return {Promise} Renderer promise.

     */

    var unsetMuted = function() {

        var userId = viewState.loggedInUserId;

        var conversationId = viewState.id;

        return Repository.unsetMutedConversations(userId, [conversationId])

            .then(function() {

                var newState = StateManager.setIsMuted(viewState, false);

                return render(newState);

            })

            .then(function() {

                return PubSub.publish(

                    MessageDrawerEvents.CONVERSATION_UNSET_MUTED,

                    formatConversationForEvent(viewState)

                );

            });

    };

    /**

     * Tell the statemanager there is a request to delete the selected messages

     * and run the renderer to show confirm delete messages dialogue.

     *

     * @param {Number} userId User id.

     */

    var requestDeleteSelectedMessages = function(userId) {

        var selectedMessageIds = viewState.selectedMessageIds;

        cancelRequest(userId);

        var newState = StateManager.addPendingDeleteMessagesById(viewState, selectedMessageIds);

        render(newState);

    };

    /**

     * Send the repository a request to delete the messages pending deletion. Update the statemanager

     * and publish a message deletion event.

     *

     * @return {Promise} Renderer promise.

     */

    var deleteSelectedMessages = function() {

        var pendingPromise = new Pending('core_message/message_drawer_view_conversation:deleteSelectedMessages');

        var messageIds = viewState.pendingDeleteMessageIds;

        var sentMessages = viewState.messages.filter(function(message) {

            // If a message sendState is null then it means it was loaded from the server or if it's

            // set to sent then it means the user has successfully sent it in this page load.

            return messageIds.indexOf(message.id) >= 0 && (message.sendState == 'sent' || message.sendState === null);

        });

        var newState = StateManager.setLoadingConfirmAction(viewState, true);

        render(newState);

        var deleteMessagesPromise = $.Deferred().resolve().promise();

        if (sentMessages.length) {

            // We only need to send a request to the server if we're trying to delete messages that

            // have successfully been sent.

            var sentMessageIds = sentMessages.map(function(message) {

                return message.id;

            });

            if (newState.deleteMessagesForAllUsers) {

                deleteMessagesPromise = Repository.deleteMessagesForAllUsers(viewState.loggedInUserId, sentMessageIds);

            } else {

                deleteMessagesPromise = Repository.deleteMessages(viewState.loggedInUserId, sentMessageIds);

            }

        }

        // Mark that we are deleting content from the  conversation to prevent updates of it.

        isDeletingConversationContent = true;

        // Stop polling for new messages to the open conversation.

        if (newMessagesPollTimer) {

            newMessagesPollTimer.stop();

        }

        return deleteMessagesPromise.then(function() {

                var newState = StateManager.removeMessagesById(viewState, messageIds);

                newState = StateManager.removePendingDeleteMessagesById(newState, messageIds);

                newState = StateManager.removeSelectedMessagesById(newState, messageIds);

                newState = StateManager.setLoadingConfirmAction(newState, false);

                newState = StateManager.setDeleteMessagesForAllUsers(newState, false);

                var prevLastMessage = viewState.messages[viewState.messages.length - 1];

                var newLastMessage = newState.messages.length ? newState.messages[newState.messages.length - 1] : null;

                if (newLastMessage && newLastMessage.id != prevLastMessage.id) {

                    var conversation = formatConversationForEvent(newState);

                    PubSub.publish(MessageDrawerEvents.CONVERSATION_NEW_LAST_MESSAGE, conversation);

                } else if (!newState.messages.length) {

                    PubSub.publish(MessageDrawerEvents.CONVERSATION_DELETED, newState.id);

                }

                isDeletingConversationContent = false;

                return render(newState);

            })

            .then(function(result) {

                pendingPromise.resolve();

                return result;

            })

            .catch(Notification.exception);

    };