// src/services/browserNotificationService.js
/**
 * 浏览器原生通知服务
 * 提供系统级通知功能（Web Notifications API）
 */

import { logger } from '../utils/logger';

class BrowserNotificationService {
    constructor() {
        this.permission = this.isSupported() ? Notification.permission : 'denied';
        this.activeNotifications = new Map(); // 存储活跃的通知
    }

    /**
     * 检查浏览器是否支持通知 API
     */
    isSupported() {
        return 'Notification' in window;
    }

    /**
     * 获取当前权限状态
     * @returns {string} 'granted' | 'denied' | 'default'
     */
    getPermissionStatus() {
        if (!this.isSupported()) {
            return 'denied';
        }
        return Notification.permission;
    }

    /**
     * 请求通知权限
     * @returns {Promise<string>} 权限状态
     */
    async requestPermission() {
        if (!this.isSupported()) {
            logger.warn('browserNotificationService', 'Notifications not supported');
            return 'denied';
        }

        if (this.permission === 'granted') {
            logger.info('browserNotificationService', 'Permission already granted');
            return 'granted';
        }

        try {
            const permission = await Notification.requestPermission();
            this.permission = permission;
            logger.info('browserNotificationService', `Permission ${permission}`);
            return permission;
        } catch (error) {
            logger.error('browserNotificationService', 'requestPermission', error);
            return 'denied';
        }
    }

    /**
     * 发送浏览器通知
     * @param {Object} options 通知选项
     * @param {string} options.title 标题
     * @param {string} options.body 内容
     * @param {string} options.icon 图标路径
     * @param {string} options.tag 标签（防止重复）
     * @param {boolean} options.requireInteraction 是否需要用户交互才关闭
     * @param {Object} options.data 自定义数据（如跳转链接）
     * @param {number} options.autoClose 自动关闭时间（毫秒）
     * @returns {Notification|null} 通知对象
     */
    sendNotification({
        title,
        body,
        icon = '/logo192.png',
        tag,
        requireInteraction = false,
        data = {},
        autoClose = 0,
    }) {
        if (!this.isSupported()) {
            logger.warn('browserNotificationService', 'Notifications not supported');
            return null;
        }

        if (this.permission !== 'granted') {
            logger.warn('browserNotificationService', 'Permission not granted');
            return null;
        }

        try {
            // 关闭相同 tag 的旧通知
            if (tag && this.activeNotifications.has(tag)) {
                const oldNotification = this.activeNotifications.get(tag);
                oldNotification.close();
            }

            // 创建通知
            const notification = new Notification(title, {
                body,
                icon,
                badge: '/badge.png',
                tag: tag || `notification_${Date.now()}`,
                requireInteraction,
                data,
                silent: false, // 允许声音
            });

            // 存储通知引用
            if (tag) {
                this.activeNotifications.set(tag, notification);
            }

            // 自动关闭
            if (autoClose > 0 && !requireInteraction) {
                setTimeout(() => {
                    notification.close();
                }, autoClose);
            }

            // 通知关闭时清理引用
            notification.onclose = () => {
                if (tag) {
                    this.activeNotifications.delete(tag);
                }
            };

            logger.info('browserNotificationService', 'Notification sent', { title, tag });
            return notification;
        } catch (error) {
            logger.error('browserNotificationService', 'sendNotification', error);
            return null;
        }
    }

    /**
     * 设置通知点击处理
     * @param {Notification} notification 通知对象
     * @param {Function} navigate React Router navigate 函数
     */
    setupClickHandler(notification, navigate) {
        if (!notification) return;

        notification.onclick = (event) => {
            event.preventDefault();

            // 聚焦窗口
            window.focus();

            // 跳转链接
            if (notification.data?.link) {
                navigate(notification.data.link);
            }

            // 关闭通知
            notification.close();

            logger.info('browserNotificationService', 'Notification clicked', notification.data);
        };
    }

    /**
     * 关闭所有活跃通知
     */
    closeAll() {
        this.activeNotifications.forEach(notification => {
            notification.close();
        });
        this.activeNotifications.clear();
        logger.info('browserNotificationService', 'All notifications closed');
    }

    /**
     * 根据通知数据发送浏览器通知
     * @param {Object} notificationData 通知数据
     * @param {Function} navigate React Router navigate 函数
     */
    sendFromNotificationData(notificationData, navigate) {
        const { type, priority, title, content, link, extra } = notificationData;

        // 生成唯一 tag
        const tag = `${type}_${Date.now()}`;

        // 判断是否需要用户交互（紧急通知不自动关闭）
        const requireInteraction = priority === 'urgent';

        // 发送通知
        const notification = this.sendNotification({
            title: title || '新通知',
            body: content || '',
            tag,
            requireInteraction,
            data: { link, ...extra },
            autoClose: requireInteraction ? 0 : 8000, // 紧急通知不自动关闭
        });

        // 设置点击处理
        if (notification && navigate) {
            this.setupClickHandler(notification, navigate);
        }

        return notification;
    }
}

// 导出单例
export const browserNotificationService = new BrowserNotificationService();

export default browserNotificationService;