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

import {AppState} from 'react-native';
import AsyncStorage from '@react-native-community/async-storage';
import NotificationsIOS, {NotificationAction, NotificationCategory} from 'react-native-notifications';

import ephemeralStore from 'app/store/ephemeral_store';

const CATEGORY = 'CAN_REPLY';
const REPLY_ACTION = 'REPLY_ACTION';
export const FOREGROUND_NOTIFICATIONS_KEY = '@FOREGROUND_NOTIFICATIONS';

let replyCategory;
const replies = new Set();

class PushNotification {
    constructor() {
        this.deviceNotification = null;
        this.onRegister = null;
        this.onNotification = null;
        this.onReply = null;

        NotificationsIOS.addEventListener('remoteNotificationsRegistered', this.onRemoteNotificationsRegistered);
        NotificationsIOS.addEventListener('notificationReceivedForeground', this.onNotificationReceivedForeground);
        NotificationsIOS.addEventListener('notificationReceivedBackground', this.onNotificationReceivedBackground);
        NotificationsIOS.addEventListener('notificationOpened', this.onNotificationOpened);

        const replyAction = new NotificationAction({
            activationMode: 'background',
            title: 'Reply',
            behavior: 'textInput',
            authenticationRequired: true,
            identifier: REPLY_ACTION,
        }, this.handleReply);

        replyCategory = new NotificationCategory({
            identifier: CATEGORY,
            actions: [replyAction],
            context: 'default',
        });
    }

    handleNotification = (data, foreground, userInteraction) => {
        this.deviceNotification = {
            data,
            foreground,
            message: data.message,
            userInfo: data.userInfo,
            userInteraction,
        };

        if (this.onNotification) {
            this.onNotification(this.deviceNotification);
        }

        if (foreground) {
            this.trackForegroundNotification(data.channel_id);
        }
    };

    handleReply = (action, completed) => {
        if (action.identifier === REPLY_ACTION) {
            const data = action.notification.getData();
            const text = action.text;
            const badge = parseInt(action.notification._badge, 10) - 1; //eslint-disable-line no-underscore-dangle

            if (this.onReply && !replies.has(action.completionKey)) {
                replies.add(action.completionKey);
                this.onReply(data, text, badge, completed);
            }
        } else {
            completed();
        }
    };

    configure(options) {
        this.onRegister = options.onRegister;
        this.onNotification = options.onNotification;
        this.onReply = options.onReply;

        this.requestPermissions([replyCategory]);

        NotificationsIOS.consumeBackgroundQueue();
    }

    requestPermissions = (permissions) => {
        NotificationsIOS.requestPermissions(permissions);
    };

    localNotificationSchedule(notification) {
        if (notification.date) {
            const deviceNotification = {
                fireDate: notification.date.toISOString(),
                alertBody: notification.message,
                alertAction: '',
                userInfo: notification.userInfo,
            };

            NotificationsIOS.localNotification(deviceNotification);
        }
    }

    localNotification(notification) {
        this.deviceNotification = {
            alertBody: notification.message,
            alertAction: '',
            userInfo: notification.userInfo,
        };

        NotificationsIOS.localNotification(this.deviceNotification);
    }

    cancelAllLocalNotifications() {
        NotificationsIOS.cancelAllLocalNotifications();
    }

    onNotificationReceivedBackground = (notification) => {
        const userInteraction = AppState.currentState === 'active';

        // mark the app as started as soon as possible
        if (userInteraction) {
            ephemeralStore.appStartedFromPushNotification = true;
        }

        const info = {
            ...notification.getData(),
            message: notification.getMessage(),
        };

        if (!userInteraction) {
            this.handleNotification(info, false, userInteraction);
        }
    };

    onNotificationReceivedForeground = (notification) => {
        const info = {
            ...notification.getData(),
            message: notification.getMessage(),
        };
        this.handleNotification(info, true, false);

        NotificationsIOS.getBadgesCount((count) => {
            this.setApplicationIconBadgeNumber(count + 1);
        });
    };

    onNotificationOpened = (notification) => {
        const info = {
            ...notification.getData(),
            message: notification.getMessage(),
        };
        this.handleNotification(info, false, true);
    };

    onRemoteNotificationsRegistered = (deviceToken) => {
        if (this.onRegister) {
            this.onRegister({token: deviceToken});
        }
    };

    setApplicationIconBadgeNumber(number) {
        const count = number < 0 ? 0 : number;
        NotificationsIOS.setBadgesCount(count);
    }

    getNotification() {
        return this.deviceNotification;
    }

    resetNotification() {
        this.deviceNotification = null;
    }

    clearChannelNotifications(channelId) {
        NotificationsIOS.getDeliveredNotifications(async (notifications) => {
            let foregroundNotifications;
            try {
                const value = await AsyncStorage.getItem(FOREGROUND_NOTIFICATIONS_KEY);
                foregroundNotifications = JSON.parse(value) || {};
            } catch (e) {
                foregroundNotifications = {};
            }

            Reflect.deleteProperty(foregroundNotifications, channelId);
            AsyncStorage.setItem(FOREGROUND_NOTIFICATIONS_KEY, JSON.stringify(foregroundNotifications));

            const foregroundCount = Object.values(foregroundNotifications).reduce((a, b) => a + b, 0);
            let badgeCount = notifications.length + foregroundCount;

            const ids = [];
            for (let i = 0; i < notifications.length; i++) {
                const notification = notifications[i];

                if (notification.userInfo.channel_id === channelId) {
                    ids.push(notification.identifier);
                }
            }

            if (ids.length) {
                badgeCount -= ids.length;
                NotificationsIOS.removeDeliveredNotifications(ids);
            }

            this.setApplicationIconBadgeNumber(badgeCount);
        });
    }

    trackForegroundNotification = async (channelId) => {
        const value = await AsyncStorage.getItem(FOREGROUND_NOTIFICATIONS_KEY);
        const foregroundNotifications = value ? JSON.parse(value) : {};
        if (!foregroundNotifications.hasOwnProperty(channelId)) {
            foregroundNotifications[channelId] = 0;
        }
        foregroundNotifications[channelId] += 1;
        await AsyncStorage.setItem(FOREGROUND_NOTIFICATIONS_KEY, JSON.stringify(foregroundNotifications));
    }

    clearForegroundNotifications = () => {
        AsyncStorage.removeItem(FOREGROUND_NOTIFICATIONS_KEY);
    };

    clearNotifications = () => {
        this.setApplicationIconBadgeNumber(0);
        this.cancelAllLocalNotifications(); // TODO: Only cancel the local notifications that belong to this server
        this.clearForegroundNotifications(); // TODO: Only clear the foreground notifications that belong to this server
    }
}

export default new PushNotification();