'use strict';

// Third Party Dependencies
const electron = require('electron');
const app = electron.app;
const crashReporter = electron.crashReporter;
const nodeURL = require('url');
const shellPath = require('shell-path');
const urlParser = require('url');
const nodePath = require('path');
require('electron-dl')();

const { version, clientVersion, buildNumber } = require('../package.json');
const log = require('./log.js');
const logLevels = require('./enums/logLevels.js');

log.send(logLevels.INFO, `-----------------Starting the app with version ${version}-----------------`);

// Local Dependencies
require('./stats');
const { getConfigField, readConfigFileSync, updateUserConfigOnLaunch, getUserConfigField } = require('./config.js');
const protocolHandler = require('./protocolHandler');
const { setCheckboxValues } = require('./menus/menuTemplate.js');
const autoLaunch = require('./autoLaunch');
const { handleCacheFailureCheckOnStartup, handleCacheFailureCheckOnExit} = require('./cacheHandler');

const compareSemVersions = require('./utils/compareSemVersions.js');
const { isMac, isDevEnv } = require('./utils/misc.js');
const getCmdLineArg = require('./utils/getCmdLineArg.js');

//setting the env path child_process issue https://github.com/electron/electron/issues/7688
shellPath()
    .then((path) => {
        process.env.PATH = path
    })
    .catch(() => {
        process.env.PATH = [
            './node_modules/.bin',
            '/usr/local/bin',
            process.env.PATH
        ].join(':');
    });

// used to check if a url was opened when the app was already open
let isAppAlreadyOpen = false;

require('./mainApiMgr.js');

// monitor memory of main process
require('./memoryMonitor.js');

const windowMgr = require('./windowMgr.js');
const { ContextMenuBuilder } = require('electron-spellchecker');
const i18n = require('./translation/i18n');

getConfigField('url')
    .then(initializeCrashReporter)
    .catch(app.quit);

function initializeCrashReporter(podUrl) {

    getConfigField('crashReporter')
        .then((crashReporterConfig) => {
            crashReporter.start({ companyName: crashReporterConfig.companyName, submitURL: crashReporterConfig.submitURL, uploadToServer: crashReporterConfig.uploadToServer, extra: { 'process': 'main', podUrl: podUrl } });
            log.send(logLevels.INFO, 'initialized crash reporter on the main process!');
        })
        .catch((err) => {
            log.send(logLevels.ERROR, 'Unable to initialize crash reporter in the main process. Error is -> ' + err);
        });

}

const allowMultiInstance = getCmdLineArg(process.argv, '--multiInstance', true) || isDevEnv;

if (!allowMultiInstance) {
    const gotTheLock = app.requestSingleInstanceLock();

    // quit if another instance is already running, ignore for dev env or if app was started with multiInstance flag
    if (!gotTheLock) {
        app.quit()
    } else {
        app.on('second-instance', (event, argv) => {
            // Someone tried to run a second instance, we should focus our window.
            log.send(logLevels.INFO, `Second instance created with args ${argv}`);
            let mainWin = windowMgr.getMainWindow();
            if (mainWin) {
                isAppAlreadyOpen = true;
                if (mainWin.isMinimized()) {
                    mainWin.restore();
                }
                mainWin.focus();
            }
            processProtocolAction(argv);
        });
    }
} else {
    app.releaseSingleInstanceLock();
}

/**
 * Sets chrome authentication flags in electron
 */
function setChromeFlags() {    

    // Read the config parameters synchronously
    let config = readConfigFileSync();

    // If we cannot find any config, just skip setting any flags
    if (config && config.customFlags) {

        if (config.customFlags.authServerWhitelist && config.customFlags.authServerWhitelist !== "") {            
            app.commandLine.appendSwitch('auth-server-whitelist', config.customFlags.authServerWhitelist);
        }

        if (config.customFlags.authNegotiateDelegateWhitelist && config.customFlags.authNegotiateDelegateWhitelist !== "") {            
            app.commandLine.appendSwitch('auth-negotiate-delegate-whitelist', config.customFlags.authNegotiateDelegateWhitelist);
        }

        if (config.customFlags.disableGpu) {            
            app.commandLine.appendSwitch("disable-gpu", true);
            app.commandLine.appendSwitch("disable-gpu-compositing", true);
            app.commandLine.appendSwitch("disable-d3d11", true);
        }

    }

    app.commandLine.appendSwitch("disable-background-timer-throttling", true);

    setChromeFlagsFromCommandLine();

}

/**
 * Parse arguments from command line 
 * and set as chrome flags if applicable
 */
function setChromeFlagsFromCommandLine() {
    log.send(logLevels.INFO, 'Setting chrome flags from command line args!');

    // Special args that need to be excluded as part of the chrome command line switch
    let specialArgs = ['--url', '--multiInstance', '--userDataPath=', 'symphony://', '--inspect-brk', '--inspect'];
    
    const cmdArgs = process.argv;
    cmdArgs.forEach((arg) => {
        // We need to check if the argument key matches the one
        // in the special args array and return if it does match
        const argSplit = arg.split('=');
        const argKey = argSplit[0];
        const argValue = argSplit[1] && arg.substring(arg.indexOf('=')+1);
        if (arg.startsWith('--') && specialArgs.includes(argKey)) {
            return;
        }

        // All the chrome flags starts with --
        // So, any other arg (like 'electron' or '.')
        // need to be skipped
        if (arg.startsWith('--')) {
            // Since chrome takes values after an equals
            // We split the arg and set it either as 
            // just a key, or as a key-value pair            
            if (argKey && argValue) {
                app.commandLine.appendSwitch(argKey.substr(2), argValue);
            } else {
                app.commandLine.appendSwitch(argKey);
            }
            log.send(logLevels.INFO, `Appended chrome command line switch ${argKey} with value ${argValue}`);
        }

    });
}

// Set the chrome flags
setChromeFlags();

/**
 * This method will be called when Electron has finished
 * initialization and is ready to create browser windows.
 * Some APIs can only be used after this event occurs.
 */
app.on('ready', () => {
    log.send(logLevels.INFO, `App is ready, proceeding to load the POD`);
    handlePowerEvents();
    handleCacheFailureCheckOnStartup()
        .then(() => {
            initiateApp();
        })
        .catch((err) => {
            log.send(logLevels.INFO, `Couldn't clear cache and refresh -> ${err}`);
            initiateApp();
        });

    function initiateApp() {
        checkFirstTimeLaunch()
            .then(readConfigThenOpenMainWindow)
            .catch(readConfigThenOpenMainWindow);

    }
});

/**
 * Is triggered when all the windows are closed
 * In which case we quit the app
 */
app.on('window-all-closed', function () {
    log.send(logLevels.INFO, `All windows closed, quitting the app`);
    app.quit();
});

app.on('quit', function () {
    log.send(logLevels.INFO, `-----------------Quitting the app-----------------`);
    handleCacheFailureCheckOnExit();    
});

/**
 * Is triggered when the app is up & running
 */
app.on('activate', function () {
    log.send(logLevels.INFO, `SDA is activated again`);
    if (windowMgr.isMainWindow(null)) {
        log.send(logLevels.INFO, `Main window instance is null, creating new instance`);
        setupThenOpenMainWindow();
    } else {
        log.send(logLevels.INFO, `Main window instance is available, showing it`);
        windowMgr.showMainWindow();
    }
});

// adds 'symphony' as a protocol in the system. plist file in macOS

// on windows, we create the protocol handler via the installer
// because electron leaves registry traces upon uninstallation
if (isMac) {
    app.setAsDefaultProtocolClient('symphony');
    // Sets application version info that will be displayed in about app panel
    app.setAboutPanelOptions({ applicationVersion: `${clientVersion}-${version}`, version: buildNumber });
}

/**
 * This event is emitted only on macOS
 * at this moment, support for windows
 * is in pipeline (https://github.com/electron/electron/pull/8052)
 */
app.on('open-url', function (event, url) {
    log.send(logLevels.INFO, `Open URL event triggered with url ${JSON.stringify(url)}`);
    handleProtocolAction(url);
});

app.on('web-contents-created', function (event, webContents) {
    onWebContent(webContents);
});

function onWebContent(webContents) {
    const spellchecker = windowMgr.getSpellchecker();
    spellchecker.initializeSpellChecker();
    spellchecker.updateContextMenuLocale(i18n.getMessageFor('ContextMenu'));
    const contextMenuBuilder = new ContextMenuBuilder(spellchecker.spellCheckHandler, webContents, false, spellchecker.processMenu.bind(spellchecker));
    let currentLocale = i18n.getLanguage();

    const contextMenuListener = (event, info) => {
        log.send(logLevels.INFO, `Context menu event triggered for web contents with info ${JSON.stringify(info)}`);
        if (currentLocale !== i18n.getLanguage()) {
            contextMenuBuilder.setAlternateStringFormatter(spellchecker.getStringTable(i18n.getMessageFor('ContextMenu')));
            spellchecker.updateContextMenuLocale(i18n.getMessageFor('ContextMenu'));
            currentLocale = i18n.getLanguage();
        }
        contextMenuBuilder.showPopupMenu(info);
    };

    webContents.on('context-menu', contextMenuListener);

    webContents.once('destroyed', () => {
        webContents.removeListener('context-menu', contextMenuListener);
    });
}

/**
 * Reads the config fields that are required for the menu items
 * then opens the main window
 *
 * This is a workaround for the issue where the menu template was returned
 * even before the config data was populated
 * https://perzoinc.atlassian.net/browse/ELECTRON-154
 */
function readConfigThenOpenMainWindow() {
    setCheckboxValues()
        .then(setupThenOpenMainWindow)
        .catch(setupThenOpenMainWindow)
}

/**
 * Sets up the app (to handle various things like config changes, protocol handling etc.)
 * and opens the main window
 */
function setupThenOpenMainWindow() {

    processProtocolAction(process.argv);

    isAppAlreadyOpen = true;
    getUrlAndCreateMainWindow();

    // Allows a developer to set custom user data path from command line when
    // launching the app. Mostly used for running automation tests with
    // multiple instances
    let customDataArg = getCmdLineArg(process.argv, '--userDataPath=', false);
    let customDataFolder = customDataArg && customDataArg.substring(customDataArg.indexOf('=') + 1);

    if (customDataArg && customDataFolder) {
        app.setPath('userData', customDataFolder);
    }

    // Event that fixes the remote desktop issue in Windows
    // by repositioning the browser window
    electron.screen.on('display-removed', windowMgr.verifyDisplays);

}

function checkFirstTimeLaunch() {
    return getUserConfigField('configVersion')
        .then((configVersion) => {
            const appVersionString = app.getVersion().toString();
            const execPath = nodePath.dirname(app.getPath('exe'));
            const shouldUpdateUserConfig = execPath.indexOf('AppData\\Local\\Programs') !== -1 || isMac;

            if (!(configVersion
                && typeof configVersion === 'string'
                && (compareSemVersions.check(appVersionString, configVersion) !== 1)) && shouldUpdateUserConfig) {
                return setupFirstTimeLaunch();
            }
            log.send(logLevels.INFO, `not a first-time launch as 
            configVersion: ${configVersion} appVersion: ${appVersionString} shouldUpdateUserConfig: ${shouldUpdateUserConfig}`);
            return Promise.resolve();
        })
        .catch(() => {
            return setupFirstTimeLaunch();
        });
}

/**
 * Setup and update user config
 * on first time launch or if the latest app version
 *
 * @return {Promise<any>}
 */
function setupFirstTimeLaunch() {
    log.send(logLevels.INFO, 'setting first time launch config');
    return getConfigField('launchOnStartup')
        .then(setStartup)
        .then(updateUserConfigOnLaunch);
}

/**
 * Sets Symphony on startup
 * @param lStartup
 * @returns {Promise}
 */
function setStartup(lStartup) {
    log.send(logLevels.INFO, `launch on startup parameter value is ${lStartup}`);
    return new Promise((resolve) => {
        let launchOnStartup = (String(lStartup) === 'true');
        log.send(logLevels.INFO, `launchOnStartup value is ${launchOnStartup}`);
        if (launchOnStartup) {
            log.send(logLevels.INFO, `enabling launch on startup`);
            autoLaunch.enable();
            return resolve();
        }
        autoLaunch.disable();
        return resolve();
    });
}

/**
 * Checks for the url argument, processes it
 * and creates the main window
 */
function getUrlAndCreateMainWindow() {
    // allow passing url argument
    let url = getCmdLineArg(process.argv, '--url=', false);
    if (url) {
        windowMgr.createMainWindow(url.substr(6));
        return;
    }

    getConfigField('url')
        .then(createWin).catch(function (err) {
            log.send(logLevels.ERROR, `unable to create main window -> ${err}`);
            app.quit();
        });
}

/**
 * Creates a window
 * @param urlFromConfig
 */
function createWin(urlFromConfig) {
    // add https protocol if none found.
    let parsedUrl = nodeURL.parse(urlFromConfig);

    if (!parsedUrl.protocol || parsedUrl.protocol !== 'https') {
        parsedUrl.protocol = 'https:';
        parsedUrl.slashes = true
    }
    let url = nodeURL.format(parsedUrl);

    windowMgr.createMainWindow(url);
}

/**
 * processes protocol action for windows clients
 * @param argv {Array} an array of command line arguments
 */
function processProtocolAction(argv) {

    // In case of windows, we need to handle protocol handler
    // manually because electron doesn't emit
    // 'open-url' event on windows
    if (!(process.platform === 'win32')) {
        return;
    }

    let protocolUri = getCmdLineArg(argv, 'symphony://', false);
    log.send(logLevels.INFO, `Trying to process a protocol action for uri ${protocolUri}`);

    if (protocolUri) {
        const parsedURL = urlParser.parse(protocolUri);
        if (!parsedURL.protocol || !parsedURL.slashes) {
            return;
        }
        log.send(logLevels.INFO, `Parsing protocol url successful for ${parsedURL}`);
        handleProtocolAction(protocolUri);
    }
}

/**
 * Handles a protocol action based on the current state of the app
 * @param uri
 */
function handleProtocolAction(uri) {
    if (!isAppAlreadyOpen) {
        log.send(logLevels.INFO, `App started by protocol url ${uri}. We are caching this to be processed later!`);
        // app is opened by the protocol url, cache the protocol url to be used later
        protocolHandler.setProtocolUrl(uri);
    } else {
        // This is needed for mac OS as it brings pop-outs to foreground
        // (if it has been previously focused) instead of main window
        if (isMac) {
            const mainWindow = windowMgr.getMainWindow();
            if (mainWindow && !mainWindow.isDestroyed()) {
                windowMgr.activate(mainWindow.winName);
            }
        }
        // app is already open, so, just trigger the protocol action method
        log.send(logLevels.INFO, `App opened by protocol url ${uri}`);
        protocolHandler.processProtocolAction(uri);
    }
}

const handlePowerEvents = () => {
    
    const events = [
        'suspend', 'resume', 'on-ac', 'on-battery', 'shutdown', 'lock-screen', 'unlock-screen'
    ];

    events.forEach((appEvent) => {
        electron.powerMonitor.on(appEvent, () => {
            log.send(logLevels.INFO, `Power Monitor Event Occurred: ${appEvent}`)
        });
    });
};