'use strict';
//
// code here adapted from https://www.npmjs.com/package/electron-notify
// made following changes:
// - place notification in corner of screen
// - notification color
// - notification flash/blink
// - custom design for symphony notification style
// - if screen added/removed or size change then close all notifications
//
const path = require('path');
const fs = require('fs');
const electron = require('electron');
const asyncMap = require('async.map');
const asyncMapSeries = require('async.mapseries');
const app = electron.app;
const BrowserWindow = electron.BrowserWindow;
const ipc = electron.ipcMain;
const { isMac, isNodeEnv } = require('../utils/misc');
const log = require('../log.js');
const logLevels = require('../enums/logLevels.js');

// maximum number of notifications that can be queued, after limit is
// reached then error func callback will be invoked.
const MAX_QUEUE_SIZE = 30;

let AnimationQueue = require('./AnimationQueue.js');

// Array of windows with currently showing notifications
let activeNotifications = [];

// Recycle windows
let inactiveWindows = [];

// If we cannot show all notifications, queue them
let notificationQueue = [];

// To prevent executing mutliple animations at once
let animationQueue = new AnimationQueue();

// To prevent double-close notification window
let closedNotifications = {};

// Give each notification a unique id
let latestID = 0;

let nextInsertPos = {};
let externalDisplay;
// user selected display id for notification
let displayId;

let sandboxed = false;

let config = {
    // corner to put notifications
    // upper-right, upper-left, lower-right, lower-left
    startCorner: 'upper-right',
    width: 380,
    height: 70,
    borderRadius: 5,
    displayTime: 5000,
    animationSteps: 5,
    animationStepMs: 5,
    animateInParallel: true,
    pathToModule: '',
    logging: true,
    defaultStyleContainer: {
        display: 'flex',
        justifyContent: 'center',
        backgroundColor: '#f0f0f0',
        overflow: 'hidden',
        position: 'relative',
        lineHeight: '15px',
        boxSizing: 'border-box'
    },
    defaultStyleHeader: {
        width: 245,
        minWidth: 230,
        margin: "12px 10px"
    },
    defaultStyleImage: {
        height: 43,
        borderRadius: 4,
        marginTop: 12,
        width: 43
    },
    defaultStyleClose: {
        width: 16,
        height: 16,
        margin: "10px 8px 0 8px",
        opacity: 0.54,
        fontSize: 12,
        color: '#CCC'
    },
    defaultStyleTitle: {
        fontFamily: 'sans-serif',
        fontSize: 14,
        fontWeight: 700,
        color: '#4a4a4a',
        overflow: 'hidden',
        display: '-webkit-box',
        webkitLineClamp: 1,
        webkitBoxOrient: 'vertical',
    },
    defaultStylePod: {
        fontFamily: 'sans-serif',
        fontSize: 11,
        color: '#adadad',
        overflow: 'hidden',
        filter: 'brightness(70%)',
        display: '-webkit-box',
        webkitLineClamp: 1,
        webkitBoxOrient: 'vertical',
    },
    defaultStyleText: {
        fontFamily: 'sans-serif',
        fontSize: 12,
        color: '#4a4a4a',
        marginTop: 12,
        overflow: 'hidden',
        display: '-webkit-box',
        webkitLineClamp: 1,
        webkitBoxOrient: 'vertical',
        cursor: 'default'
    },
    defaultStyleLogo: {
        margin: "12px 0 0 -12px",
        opacity: 0.6,
    },
    defaultWindow: {
        alwaysOnTop: true,
        skipTaskbar: true,
        resizable: false,
        show: false,
        frame: false,
        transparent: true,
        acceptFirstMouse: true,
        webPreferences: {
            preload: path.join(__dirname, 'electron-notify-preload.js'),
            sandbox: sandboxed,
            nodeIntegration: isNodeEnv
        }
    }
};

if (app.isReady()) {
    setup();
} else {
    app.on('ready', setup);
}

/**
 * Method to update notification config
 * @param customConfig
 */
function updateConfig(customConfig) {
    // Fetching user preferred notification position from config
    if (customConfig.position) {
        config = Object.assign(config, {startCorner: customConfig.position});

        calcDimensions();
    }

    // Fetching user preferred notification screen from config
    if (customConfig.display) {
        displayId = customConfig.display;
    }
}

/**
 * Method to setup the notification configuration
 */
function setup() {
    setupConfig();

    // if display added/removed/changed then re-run setup and remove all existing
    // notifications.
    electron.screen.on('display-added', setupConfig);
    electron.screen.on('display-removed', setupConfig);
    electron.screen.on('display-metrics-changed', setupConfig);
}

/**
 * Method to get the notification template path
 * @returns {string|*}
 */
function getTemplatePath() {
    let templatePath = path.join(__dirname, 'electron-notify.html');
    try {
        fs.statSync(templatePath).isFile();
    } catch (err) {
        log.send(logLevels.ERROR, 'electron-notify: Could not find template ("' + templatePath + '").');
    }
    config.templatePath = 'file://' + templatePath;
    return config.templatePath;
}

/**
 * Calculates the dimensions of the screen
 */
function calcDimensions() {
    const vertSpaceBetweenNotf = 8;

    // Calc totalHeight & totalWidth
    config.totalHeight = config.height + vertSpaceBetweenNotf;
    config.totalWidth = config.width;

    let firstPosX, firstPosY;
    switch (config.startCorner) {
        case 'upper-right':
            firstPosX = config.corner.x - config.totalWidth;
            firstPosY = config.corner.y;
            break;
        case 'lower-right':
            firstPosX = config.corner.x - config.totalWidth;
            firstPosY = config.corner.y - config.totalHeight;
            break;
        case 'lower-left':
            firstPosX = config.corner.x;
            firstPosY = config.corner.y - config.totalHeight;
            break;
        case 'upper-left':
        default:
            firstPosX = config.corner.x;
            firstPosY = config.corner.y;
            break;
    }

    // Calc pos of first notification:
    config.firstPos = {
        x: firstPosX,
        y: firstPosY
    };

    // Set nextInsertPos
    nextInsertPos.x = config.firstPos.x;
    nextInsertPos.y = config.firstPos.y
}

/**
 * Setup the notification config
 */
function setupConfig() {

    // This feature only applies to windows
    if (!isMac) {
        let screens = electron.screen.getAllDisplays();
        if (screens && screens.length >= 0) {
            externalDisplay = screens.find((screen) => {
                let screenId = screen.id.toString();
                return screenId === displayId;
            });
        }
    }

    let display = externalDisplay ? externalDisplay : electron.screen.getPrimaryDisplay();
    config.corner = {};
    config.corner.x = display.workArea.x;
    config.corner.y = display.workArea.y;

    // update corner x/y based on corner of screen where notf should appear
    const workAreaWidth = display.workAreaSize.width;
    const workAreaHeight = display.workAreaSize.height;
    switch (config.startCorner) {
        case 'upper-right':
            config.corner.x += workAreaWidth;
            break;
        case 'lower-right':
            config.corner.x += workAreaWidth;
            config.corner.y += workAreaHeight;
            break;
        case 'lower-left':
            config.corner.y += workAreaHeight;
            break;
        case 'upper-left':
        default:
            // no change needed
            break;
    }

    calcDimensions();

    // Maximum amount of Notifications we can show:
    config.maxVisibleNotifications = Math.floor(display.workAreaSize.height / config.totalHeight);
    config.maxVisibleNotifications = config.maxVisibleNotifications > 5 ? 5 : config.maxVisibleNotifications;
}

/**
 * Notifies the user
 * @param notification
 * @returns {*}
 */
function notify(notification) {
    // Is it an object and only one argument?
    if (arguments.length === 1 && typeof notification === 'object') {
        let notf = Object.assign({}, notification);
        // Use object instead of supplied parameters
        notf.id = latestID;
        incrementId();
        animationQueue.push({
            func: showNotification,
            args: [ notf ]
        });
        return notf.id
    }
    log.send(logLevels.ERROR, 'electron-notify: ERROR notify() only accepts a single object with notification parameters.');
    return null;
}

/**
 * Increment the notification
 */
function incrementId() {
    latestID++;
}

/**
 * Shows the notification to the user
 * @param notificationObj
 * @returns {Promise}
 */
function showNotification(notificationObj) {
    return new Promise(function(resolve) {

        if (notificationQueue.length >= MAX_QUEUE_SIZE) {
            if (typeof notificationObj.onErrorFunc === 'function') {
                setTimeout(function() {
                    notificationObj.onErrorFunc({
                        id: notificationObj.id,
                        error: 'max notification queue size reached: ' + MAX_QUEUE_SIZE
                    });
                    log.send(logLevels.INFO, 'showNotification: max notification queue size reached: ' + MAX_QUEUE_SIZE);
                }, 0);
            }
            resolve();
            return;
        }

        // check if tag id provided.  should replace existing notification
        // if has same grouping id.
        let tag = notificationObj.tag;
        if (tag) {
            // first check queued notifications
            for(let i = 0; i < notificationQueue.length; i++) {
                if (tag === notificationQueue[ i ].tag) {
                    let existingNotfObj = notificationQueue[ i ];
                    // be sure to call close event for existing, so it gets
                    // cleaned up.
                    if (typeof existingNotfObj.onCloseFunc === 'function') {
                        existingNotfObj.onCloseFunc({
                            event: 'close',
                            id: notificationObj.id
                        });
                    }
                    // update with new notf
                    notificationQueue[ i ] = notificationObj;
                    resolve();
                    return;
                }
            }

            // next check notfs being shown
            for(let i = 0; i < activeNotifications.length; i++) {
                let existingNotfyObj = activeNotifications[ i ].notfyObj;
                if (existingNotfyObj && tag === existingNotfyObj.tag) {
                    let notificationWindow = activeNotifications[ i ];

                    // be sure to call close event for existing, so it gets
                    // cleaned up.
                    if (notificationWindow.electronNotifyOnCloseFunc) {
                        notificationWindow.electronNotifyOnCloseFunc({
                            event: 'close',
                            id: existingNotfyObj.id
                        });
                        delete notificationWindow.electronNotifyOnCloseFunc;
                    }
                    setNotificationContents(notificationWindow, notificationObj);
                    resolve();
                    return;
                }
            }
        }

        // Can we show it?
        if (activeNotifications.length < config.maxVisibleNotifications) {
            // Get inactiveWindow or create new:
            getWindow().then(function(notificationWindow) {
                // Move window to position
                calcInsertPos();
                setWindowPosition(notificationWindow, nextInsertPos.x, nextInsertPos.y);

                let updatedNotfWindow = setNotificationContents(notificationWindow, notificationObj);

                activeNotifications.push(updatedNotfWindow);

                resolve(updatedNotfWindow);
            })
        } else {
            // Add to notificationQueue
            notificationQueue.push(notificationObj);
            resolve();
        }
    })
}

/**
 * Sets the HTML notification contents along with other options
 * @param notfWindow
 * @param notfObj
 * @returns {*}
 */
function setNotificationContents(notfWindow, notfObj) {

    // Display time per notification basis.
    let displayTime = notfObj.displayTime ? notfObj.displayTime : config.displayTime;

    if (notfWindow.displayTimer) {
        clearTimeout(notfWindow.displayTimer);
    }

    const updatedNotificationWindow = notfWindow;

    updatedNotificationWindow.notfyObj = notfObj;

    let timeoutId;
    let closeFunc = buildCloseNotification(notfWindow, notfObj, function() {
        return timeoutId
    });
    let closeNotificationSafely = buildCloseNotificationSafely(closeFunc);

    // don't start timer to close if we aren't sticky
    if (!notfObj.sticky) {
        timeoutId = setTimeout(function() {
            closeNotificationSafely('timeout');
        }, displayTime);
        updatedNotificationWindow.displayTimer = timeoutId;
    }

    // Trigger onShowFunc if existent
    if (notfObj.onShowFunc) {
        notfObj.onShowFunc({
            event: 'show',
            id: notfObj.id,
            closeNotification: closeNotificationSafely
        })
    }

    // Save onClickFunc in notification window
    if (notfObj.onClickFunc) {
        updatedNotificationWindow.electronNotifyOnClickFunc = notfObj.onClickFunc
    } else {
        delete updatedNotificationWindow.electronNotifyOnClickFunc;
    }

    if (notfObj.onCloseFunc) {
        updatedNotificationWindow.electronNotifyOnCloseFunc = notfObj.onCloseFunc
    } else {
        delete updatedNotificationWindow.electronNotifyOnCloseFunc;
    }

    const windowId = notfWindow.id;
    // Set contents, ...
    updatedNotificationWindow.webContents.send('electron-notify-set-contents',
        Object.assign({ windowId: windowId}, notfObj));
    // Show window
    updatedNotificationWindow.showInactive();

    return updatedNotificationWindow;
}

/**
 * Closes the notification
 * @param notificationWindow
 * @param notificationObj
 * @param getTimeoutId
 * @returns {Function}
 */
function buildCloseNotification(notificationWindow, notificationObj, getTimeoutId) {
    return function(event) {
        if (closedNotifications[notificationObj.id]) {
            delete closedNotifications[notificationObj.id];
            return new Promise(function(exitEarly) { exitEarly() });
        }
        closedNotifications[notificationObj.id] = true;


        if (notificationWindow.electronNotifyOnCloseFunc) {
            notificationWindow.electronNotifyOnCloseFunc({
                event: event,
                id: notificationObj.id
            });
            // ToDo: fix this: shouldn't delete method on arg
            /* eslint-disable */
            delete notificationWindow.electronNotifyOnCloseFunc;
            /* eslint-enable */
        }

        // reset content
        notificationWindow.webContents.send('electron-notify-reset');
        if (getTimeoutId && typeof getTimeoutId === 'function') {
            let timeoutId = getTimeoutId();
            clearTimeout(timeoutId);
        }

        // Recycle window
        let pos = activeNotifications.indexOf(notificationWindow);
        activeNotifications.splice(pos, 1);
        inactiveWindows.push(notificationWindow);

        // Hide notification
        notificationWindow.hide();

        checkForQueuedNotifications();

        // Move notifications down
        return moveOneDown(pos);
    }
}

/**
 * Adds an active notification the close notification queue
 * Always add to animationQueue to prevent erros (e.g. notification
 * got closed while it was moving will produce an error)
 * @param closeFunc
 * @returns {Function}
 */
function buildCloseNotificationSafely(closeFunc) {
    return function(reason) {
        animationQueue.push({
            func: closeFunc,
            args: [ reason || 'closedByAPI' ]
        });
    }
}

ipc.on('electron-notify-close', function (event, winId, notificationObj) {
    let closeFunc = buildCloseNotification(BrowserWindow.fromId(winId), notificationObj);
    buildCloseNotificationSafely(closeFunc)('close');
});

ipc.on('electron-notify-click', function (event, winId, notificationObj) {
    let notificationWindow = BrowserWindow.fromId(winId);
    if (notificationWindow && notificationWindow.electronNotifyOnClickFunc) {
        let closeFunc = buildCloseNotification(notificationWindow, notificationObj);
        notificationWindow.electronNotifyOnClickFunc({
            event: 'click',
            id: notificationObj.id,
            closeNotification: buildCloseNotificationSafely(closeFunc)
        });
        delete notificationWindow.electronNotifyOnClickFunc;
    }
});

/**
 * Checks for queued notifications and add them
 * to AnimationQueue if possible
 */
function checkForQueuedNotifications() {
    if (notificationQueue.length > 0 &&
    activeNotifications.length < config.maxVisibleNotifications) {
    // Add new notification to animationQueue
        animationQueue.push({
            func: showNotification,
            args: [ notificationQueue.shift() ]
        })
    }
}

/**
 * Moves the notifications one position down,
 * starting with notification at startPos
 * @param startPos
 * @returns {Promise}
 */
function moveOneDown(startPos) {
    return new Promise(function(resolve) {
        if (startPos >= activeNotifications || startPos === -1) {
            resolve();
            return
        }
    // Build array with index of affected notifications
        let notificationPosArray = [];
        for (let i = startPos; i < activeNotifications.length; i++) {
            notificationPosArray.push(i)
        }
    // Start to animate all notifications at once or in parallel
        let asyncFunc = asyncMap; // Best performance
        if (config.animateInParallel === false) {
            asyncFunc = asyncMapSeries // Sluggish
        }
        asyncFunc(notificationPosArray, moveNotificationAnimation, function() {
            resolve()
        })
    })
}

/**
 * Moves the notification animation
 * @param i
 * @param done
 */
function moveNotificationAnimation(i, done) {
    // Get notification to move
    let notificationWindow = activeNotifications[i];

    // Calc new y position
    let newY;
    switch(config.startCorner) {
        case 'upper-right':
        case 'upper-left':
            newY = config.corner.y + (config.totalHeight * i);
            break;
        default:
        case 'lower-right':
        case 'lower-left':
            newY = config.corner.y - (config.totalHeight * (i + 1));
            break;
    }

    // Get startPos, calc step size and start animationInterval
    let startY = notificationWindow.getPosition()[1];
    let step = (newY - startY) / config.animationSteps;
    let curStep = 1;
    let animationInterval = setInterval(function() {
        // Abort condition
        if (curStep === config.animationSteps) {
            setWindowPosition(notificationWindow, config.firstPos.x, newY);
            clearInterval(animationInterval);
            done(null, 'done');
            return;
        }
        // Move one step down
        setWindowPosition(notificationWindow, config.firstPos.x, startY + curStep * step);
        curStep++
    }, config.animationStepMs)
}

/**
 * Sets the window's position
 * @param browserWin
 * @param posX
 * @param posY
 */
function setWindowPosition(browserWin, posX, posY) {
    if (!browserWin.isDestroyed()) {
        browserWin.setPosition(parseInt(posX, 10), parseInt(posY, 10))
    }
}

/**
 * Find next possible insert position (on top)
 */
function calcInsertPos() {
    if (activeNotifications.length < config.maxVisibleNotifications) {
        switch(config.startCorner) {
            case 'upper-right':
            case 'upper-left':
                nextInsertPos.y = config.corner.y + (config.totalHeight * activeNotifications.length);
                break;

            default:
            case 'lower-right':
            case 'lower-left':
                nextInsertPos.y = config.corner.y - (config.totalHeight * (activeNotifications.length + 1));
                break;
        }
    }
}

/**
 * Get a window to display a notification. Use inactiveWindows or
 * create a new window
 * @returns {Promise}
 */
function getWindow() {
    return new Promise(function(resolve) {
        let notificationWindow;
        // Are there still inactiveWindows?
        if (inactiveWindows.length > 0) {
            notificationWindow = inactiveWindows.pop();
            resolve(notificationWindow)
        } else {
            // Or create a new window
            let windowProperties = config.defaultWindow;
            windowProperties.width = config.width;
            windowProperties.height = config.height;
            notificationWindow = new BrowserWindow(windowProperties);
            notificationWindow.setVisibleOnAllWorkspaces(true);
            notificationWindow.loadURL(getTemplatePath());
            notificationWindow.webContents.on('did-finish-load', function() {
                // Done
                notificationWindow.webContents.send('electron-notify-load-config', config);
                resolve(notificationWindow)
            })
        }
    })
}

/**
 * Once a minute, remove inactive windows to free up memory used.
 */
setInterval(cleanUpInactiveWindow, 60000);

/**
 * Cleans up inactive windows
 */
function cleanUpInactiveWindow() {
    inactiveWindows.forEach(function(window) {
        window.close();
    });
    inactiveWindows = [];
}

module.exports.notify = notify;
module.exports.updateConfig = updateConfig;
module.exports.reset = setupConfig;