// src/store/middleware/posthogMiddleware.js
import { trackPageView } from '../../lib/posthog';
import { trackEvent } from '../slices/posthogSlice';
import { logger } from '../../utils/logger';
import {
  ACTIVATION_EVENTS,
  RETENTION_EVENTS,
  SPECIAL_EVENTS,
  REVENUE_EVENTS,
} from '../../lib/constants';

// ==================== 自动追踪规则配置 ====================

/**
 * Action 到 PostHog 事件的映射
 * 当这些 Redux actions 被 dispatch 时，自动追踪对应的 PostHog 事件
 */
const ACTION_TO_EVENT_MAP = {
  // ==================== 登录/登出 ====================
  'auth/login/fulfilled': {
    event: ACTIVATION_EVENTS.USER_LOGGED_IN,
    getProperties: (action) => ({
      login_method: action.payload?.login_method || 'unknown',
      user_id: action.payload?.user?.id,
    }),
  },
  'auth/logout': {
    event: SPECIAL_EVENTS.USER_LOGGED_OUT,
    getProperties: () => ({}),
  },
  'auth/wechatLogin/fulfilled': {
    event: ACTIVATION_EVENTS.USER_LOGGED_IN,
    getProperties: (action) => ({
      login_method: 'wechat',
      user_id: action.payload?.user?.id,
    }),
  },

  // ==================== Community/新闻模块 ====================
  'communityData/fetchHotEvents/fulfilled': {
    event: RETENTION_EVENTS.NEWS_LIST_VIEWED,
    getProperties: (action) => ({
      event_count: action.payload?.length || 0,
      source: 'community_page',
    }),
  },
  'communityData/fetchPopularKeywords/fulfilled': {
    event: RETENTION_EVENTS.COMMUNITY_PAGE_VIEWED,
    getProperties: () => ({
      feature: 'popular_keywords',
    }),
  },

  // ==================== 搜索 ====================
  'search/submit': {
    event: RETENTION_EVENTS.SEARCH_QUERY_SUBMITTED,
    getProperties: (action) => ({
      query: action.payload?.query,
      category: action.payload?.category,
    }),
  },
  'search/filterApplied': {
    event: RETENTION_EVENTS.SEARCH_FILTER_APPLIED,
    getProperties: (action) => ({
      filter_type: action.payload?.filterType,
      filter_value: action.payload?.filterValue,
    }),
  },

  // ==================== 支付/订阅 ====================
  'payment/initiated': {
    event: REVENUE_EVENTS.PAYMENT_INITIATED,
    getProperties: (action) => ({
      amount: action.payload?.amount,
      payment_method: action.payload?.method,
      subscription_tier: action.payload?.tier,
    }),
  },
  'payment/success': {
    event: REVENUE_EVENTS.PAYMENT_SUCCESSFUL,
    getProperties: (action) => ({
      amount: action.payload?.amount,
      transaction_id: action.payload?.transactionId,
      subscription_tier: action.payload?.tier,
    }),
  },
  'subscription/upgraded': {
    event: REVENUE_EVENTS.SUBSCRIPTION_UPGRADED,
    getProperties: (action) => ({
      from_tier: action.payload?.fromTier,
      to_tier: action.payload?.toTier,
    }),
  },

  // ==================== 错误追踪 ====================
  'error/occurred': {
    event: SPECIAL_EVENTS.ERROR_OCCURRED,
    getProperties: (action) => ({
      error_type: action.payload?.errorType,
      error_message: action.payload?.message,
      stack_trace: action.payload?.stack,
    }),
  },
  'api/error': {
    event: SPECIAL_EVENTS.API_ERROR,
    getProperties: (action) => ({
      endpoint: action.payload?.endpoint,
      status_code: action.payload?.statusCode,
      error_message: action.payload?.message,
    }),
  },
};

// ==================== 页面路由追踪配置 ====================

/**
 * 路由变化的 action type（根据不同路由库调整）
 */
const LOCATION_CHANGE_ACTIONS = [
  '@@router/LOCATION_CHANGE', // Redux-first router
  'router/navigate', // 自定义路由 action
];

/**
 * 根据路径识别页面类型
 */
const getPageTypeFromPath = (pathname) => {
  if (pathname === '/home' || pathname === '/') {
    return { page_type: 'landing' };
  } else if (pathname.startsWith('/auth/')) {
    return { page_type: 'auth' };
  } else if (pathname.startsWith('/community')) {
    return { page_type: 'feature', feature_name: 'community' };
  } else if (pathname.startsWith('/concepts')) {
    return { page_type: 'feature', feature_name: 'concepts' };
  } else if (pathname.startsWith('/stocks')) {
    return { page_type: 'feature', feature_name: 'stocks' };
  } else if (pathname.startsWith('/limit-analyse')) {
    return { page_type: 'feature', feature_name: 'limit_analyse' };
  } else if (pathname.startsWith('/trading-simulation')) {
    return { page_type: 'feature', feature_name: 'trading_simulation' };
  } else if (pathname.startsWith('/company')) {
    return { page_type: 'detail', content_type: 'company' };
  } else if (pathname.startsWith('/event-detail')) {
    return { page_type: 'detail', content_type: 'event' };
  }
  return { page_type: 'other' };
};

// ==================== 中间件实现 ====================

/**
 * PostHog Middleware
 * 自动拦截 Redux actions 并追踪对应的 PostHog 事件
 */
const posthogMiddleware = (store) => (next) => (action) => {
  // 先执行 action
  const result = next(action);

  // 获取当前 PostHog 状态
  const state = store.getState();
  const posthogState = state.posthog;

  // 如果 PostHog 未初始化，不追踪（事件会被缓存到 eventQueue）
  if (!posthogState?.isInitialized) {
    return result;
  }

  try {
    // ==================== 1. 自动追踪特定 actions ====================
    if (ACTION_TO_EVENT_MAP[action.type]) {
      const { event, getProperties } = ACTION_TO_EVENT_MAP[action.type];
      const properties = getProperties(action);

      // 通过 dispatch 追踪事件（会走 Redux 状态管理）
      store.dispatch(trackEvent({ eventName: event, properties }));

      logger.debug('PostHog Middleware', `自动追踪事件: ${event}`, properties);
    }

    // ==================== 2. 路由变化追踪 ====================
    if (LOCATION_CHANGE_ACTIONS.includes(action.type)) {
      const location = action.payload?.location || action.payload;
      const pathname = location?.pathname || window.location.pathname;
      const search = location?.search || window.location.search;

      // 识别页面类型
      const pageProperties = getPageTypeFromPath(pathname);

      // 追踪页面浏览
      trackPageView(pathname, {
        ...pageProperties,
        page_path: pathname,
        page_search: search,
        page_title: document.title,
        referrer: document.referrer,
      });

      logger.debug('PostHog Middleware', `页面浏览追踪: ${pathname}`, pageProperties);
    }

    // ==================== 3. 离线事件处理 ====================
    // 检测网络状态变化
    if (action.type === 'network/online') {
      // 恢复在线时，刷新缓存的事件
      const { eventQueue } = posthogState;
      if (eventQueue && eventQueue.length > 0) {
        logger.info('PostHog Middleware', `网络恢复，刷新 ${eventQueue.length} 个缓存事件`);
        // 这里可以 dispatch flushCachedEvents，但为了避免循环依赖，直接在 slice 中处理
      }
    }

    // ==================== 4. 性能追踪（可选） ====================
    // 追踪耗时较长的 actions
    const startTime = action.meta?.startTime;
    if (startTime) {
      const duration = Date.now() - startTime;
      if (duration > 1000) {
        // 超过 1 秒的操作
        store.dispatch(trackEvent({
          eventName: SPECIAL_EVENTS.PAGE_LOAD_TIME,
          properties: {
            action_type: action.type,
            duration_ms: duration,
            is_slow: true,
          },
        }));
      }
    }
  } catch (error) {
    logger.error('PostHog Middleware', '追踪失败', error, { actionType: action.type });
  }

  return result;
};

// ==================== 工具函数 ====================

/**
 * 创建带性能追踪的 action creator
 * 用法: dispatch(withTiming(someAction(payload)))
 */
export const withTiming = (action) => ({
  ...action,
  meta: {
    ...action.meta,
    startTime: Date.now(),
  },
});

/**
 * 手动触发页面浏览追踪
 * 用于非路由跳转的场景（如 Modal、Tab 切换）
 */
export const trackModalView = (modalName, properties = {}) => (dispatch) => {
  dispatch(trackEvent({
    eventName: '$pageview',
    properties: {
      modal_name: modalName,
      page_type: 'modal',
      ...properties,
    },
  }));
};

/**
 * 追踪 Tab 切换
 */
export const trackTabChange = (tabName, properties = {}) => (dispatch) => {
  dispatch(trackEvent({
    eventName: RETENTION_EVENTS.NEWS_TAB_CLICKED,
    properties: {
      tab_name: tabName,
      ...properties,
    },
  }));
};

// ==================== Export ====================

export default posthogMiddleware;