// Copyright (c) 2015 Mattermost, Inc. All Rights Reserved.
// See License.txt for license information.

import UserStore from './user_store.jsx';
import PostStore from './post_store.jsx';
import ChannelStore from './channel_store.jsx';
import BrowserStore from './browser_store.jsx';
import ErrorStore from './error_store.jsx';
import EventEmitter from 'events';

import * as Utils from '../utils/utils.jsx';
import * as AsyncClient from '../utils/async_client.jsx';
import * as EventHelpers from '../dispatcher/event_helpers.jsx';

import Constants from '../utils/constants.jsx';
const SocketEvents = Constants.SocketEvents;

const CHANGE_EVENT = 'change';

var conn;

class SocketStoreClass extends EventEmitter {
    constructor() {
        super();

        this.initialize = this.initialize.bind(this);
        this.emitChange = this.emitChange.bind(this);
        this.addChangeListener = this.addChangeListener.bind(this);
        this.removeChangeListener = this.removeChangeListener.bind(this);
        this.sendMessage = this.sendMessage.bind(this);
        this.close = this.close.bind(this);

        this.failCount = 0;

        this.translations = this.getDefaultTranslations();

        this.initialize();
    }

    initialize() {
        if (!UserStore.getCurrentId()) {
            return;
        }

        if (!global.window.hasOwnProperty('mm_session_token_index')) {
            return;
        }

        this.setMaxListeners(0);

        if (window.WebSocket && !conn) {
            var protocol = 'ws://';
            if (window.location.protocol === 'https:') {
                protocol = 'wss://';
            }

            var connUrl = protocol + location.host + ((/:\d+/).test(location.host) ? '' : Utils.getWebsocketPort(protocol)) + '/api/v1/websocket?' + Utils.getSessionIndex();

            if (this.failCount === 0) {
                console.log('websocket connecting to ' + connUrl); //eslint-disable-line no-console
                if (ErrorStore.getConnectionErrorCount() > 0) {
                    ErrorStore.setConnectionErrorCount(0);
                    ErrorStore.emitChange();
                }
            }
            conn = new WebSocket(connUrl);

            conn.onopen = () => {
                if (this.failCount > 0) {
                    console.log('websocket re-established connection'); //eslint-disable-line no-console

                    ErrorStore.clearLastError();
                    ErrorStore.emitChange();

                    AsyncClient.getChannels();
                    AsyncClient.getPosts(ChannelStore.getCurrentId());
                }

                this.failCount = 0;
            };

            conn.onclose = () => {
                conn = null;

                if (this.failCount === 0) {
                    console.log('websocket closed'); //eslint-disable-line no-console
                }

                this.failCount = this.failCount + 1;

                if (this.failCount > 7) {
                    ErrorStore.storeLastError({message: this.translations.socketError});
                }

                ErrorStore.setConnectionErrorCount(this.failCount);
                ErrorStore.emitChange();

                setTimeout(
                    () => {
                        this.initialize();
                    },
                    3000
                );
            };

            conn.onerror = (evt) => {
                if (this.failCount <= 1) {
                    console.log('websocket error'); //eslint-disable-line no-console
                    console.log(evt); //eslint-disable-line no-console
                }
            };

            conn.onmessage = (evt) => {
                const msg = JSON.parse(evt.data);
                this.handleMessage(msg);
                this.emitChange(msg);
            };
        }
    }

    emitChange(msg) {
        this.emit(CHANGE_EVENT, msg);
    }

    addChangeListener(callback) {
        this.on(CHANGE_EVENT, callback);
    }

    removeChangeListener(callback) {
        this.removeListener(CHANGE_EVENT, callback);
    }

    handleMessage(msg) {
        switch (msg.action) {
        case SocketEvents.POSTED:
        case SocketEvents.EPHEMERAL_MESSAGE:
            handleNewPostEvent(msg, this.translations);
            break;

        case SocketEvents.POST_EDITED:
            handlePostEditEvent(msg);
            break;

        case SocketEvents.POST_DELETED:
            handlePostDeleteEvent(msg);
            break;

        case SocketEvents.NEW_USER:
            handleNewUserEvent();
            break;

        case SocketEvents.USER_ADDED:
            handleUserAddedEvent(msg);
            break;

        case SocketEvents.USER_REMOVED:
            handleUserRemovedEvent(msg);
            break;

        case SocketEvents.CHANNEL_VIEWED:
            handleChannelViewedEvent(msg);
            break;

        case SocketEvents.PREFERENCE_CHANGED:
            handlePreferenceChangedEvent(msg);
            break;

        default:
        }
    }

    sendMessage(msg) {
        if (conn && conn.readyState === WebSocket.OPEN) {
            conn.send(JSON.stringify(msg));
        } else if (!conn || conn.readyState === WebSocket.Closed) {
            conn = null;
            this.initialize();
        }
    }

    setTranslations(messages) {
        this.translations = messages;
    }

    getDefaultTranslations() {
        return ({
            socketError: 'Please check connection, Mattermost unreachable. If issue persists, ask administrator to check WebSocket port.',
            someone: 'Someone',
            posted: 'Posted',
            uploadedImage: ' uploaded an image',
            uploadedFile: ' uploaded a file',
            something: ' did something new',
            wrote: ' wrote: '
        });
    }

    close() {
        if (conn && conn.readyState === WebSocket.OPEN) {
            conn.close();
        }
    }
}

function handleNewPostEvent(msg, translations) {
    // Store post
    const post = JSON.parse(msg.props.post);
    EventHelpers.emitPostRecievedEvent(post);

    // Update channel state
    if (ChannelStore.getCurrentId() === msg.channel_id) {
        if (window.isActive) {
            AsyncClient.updateLastViewedAt();
        } else {
            AsyncClient.getChannel(msg.channel_id);
        }
    } else if (UserStore.getCurrentId() !== msg.user_id || post.type !== Constants.POST_TYPE_JOIN_LEAVE) {
        AsyncClient.getChannel(msg.channel_id);
    }

    // Send desktop notification
    if ((UserStore.getCurrentId() !== msg.user_id || post.props.from_webhook === 'true') && !Utils.isSystemMessage(post)) {
        const msgProps = msg.props;

        let mentions = [];
        if (msgProps.mentions) {
            mentions = JSON.parse(msg.props.mentions);
        }

        const channel = ChannelStore.get(msg.channel_id);
        const user = UserStore.getCurrentUser();
        const member = ChannelStore.getMember(msg.channel_id);

        let notifyLevel = member && member.notify_props ? member.notify_props.desktop : 'default';
        if (notifyLevel === 'default') {
            notifyLevel = user.notify_props.desktop;
        }

        if (notifyLevel === 'none') {
            return;
        } else if (notifyLevel === 'mention' && mentions.indexOf(user.id) === -1 && channel.type !== Constants.DM_CHANNEL) {
            return;
        }

        let username = translations.someone;
        if (post.props.override_username && global.window.mm_config.EnablePostUsernameOverride === 'true') {
            username = post.props.override_username;
        } else if (UserStore.hasProfile(msg.user_id)) {
            username = UserStore.getProfile(msg.user_id).username;
        }

        let title = translations.posted;
        if (channel) {
            title = channel.display_name;
        }

        let notifyText = post.message.replace(/\n+/g, ' ');
        if (notifyText.length > 50) {
            notifyText = notifyText.substring(0, 49) + '...';
        }

        if (notifyText.length === 0) {
            if (msgProps.image) {
                Utils.notifyMe(title, username + translations.uploadedImage, channel);
            } else if (msgProps.otherFile) {
                Utils.notifyMe(title, username + translations.uploadedFile, channel);
            } else {
                Utils.notifyMe(title, username + translations.something, channel);
            }
        } else {
            Utils.notifyMe(title, username + translations.wrote + notifyText, channel);
        }
        if (!user.notify_props || user.notify_props.desktop_sound === 'true') {
            Utils.ding();
        }
    }
}

function handlePostEditEvent(msg) {
    // Store post
    const post = JSON.parse(msg.props.post);
    PostStore.storePost(post);
    PostStore.emitChange();

    // Update channel state
    if (ChannelStore.getCurrentId() === msg.channel_id) {
        if (window.isActive) {
            AsyncClient.updateLastViewedAt();
        }
    }
}

function handlePostDeleteEvent(msg) {
    const post = JSON.parse(msg.props.post);
    EventHelpers.emitPostDeletedEvent(post);
}

function handleNewUserEvent() {
    AsyncClient.getProfiles();
    AsyncClient.getChannelExtraInfo();
}

function handleUserAddedEvent(msg) {
    if (ChannelStore.getCurrentId() === msg.channel_id) {
        AsyncClient.getChannelExtraInfo();
    }

    if (UserStore.getCurrentId() === msg.user_id) {
        AsyncClient.getChannel(msg.channel_id);
    }
}

function handleUserRemovedEvent(msg) {
    if (UserStore.getCurrentId() === msg.user_id) {
        AsyncClient.getChannels();

        if (msg.props.remover_id !== msg.user_id &&
                msg.channel_id === ChannelStore.getCurrentId() &&
                $('#removed_from_channel').length > 0) {
            var sentState = {};
            sentState.channelName = ChannelStore.getCurrent().display_name;
            sentState.remover = UserStore.getProfile(msg.props.remover_id).username;

            BrowserStore.setItem('channel-removed-state', sentState);
            $('#removed_from_channel').modal('show');
        }
    } else if (ChannelStore.getCurrentId() === msg.channel_id) {
        AsyncClient.getChannelExtraInfo();
    }
}

function handleChannelViewedEvent(msg) {
    // Useful for when multiple devices have the app open to different channels
    if (ChannelStore.getCurrentId() !== msg.channel_id && UserStore.getCurrentId() === msg.user_id) {
        AsyncClient.getChannel(msg.channel_id);
    }
}

function handlePreferenceChangedEvent(msg) {
    const preference = JSON.parse(msg.props.preference);
    EventHelpers.emitPreferenceChangedEvent(preference);
}

var SocketStore = new SocketStoreClass();

export default SocketStore;
window.SocketStore = SocketStore;