/**
 * API模拟器 - 客户端模拟API功能
 * 在没有官方API的情况下，通过浏览器自动化模拟API调用
 * 支持订单同步、商品管理、数据抓取等操作
 */

import { chromium, Browser, Page, BrowserContext } from 'playwright';
import * as fs from 'fs';
import * as path from 'path';

interface ApiSimulatorConfig {
  headless: boolean;
  proxy?: string;
  userDataDir?: string; // 用户数据目录，用于保存登录状态
  timeout: number;
}

interface ApiRequest {
  method: 'GET' | 'POST' | 'PUT' | 'DELETE';
  endpoint: string; // 模拟的API端点，如 'orders', 'products'
  params: Record<string, any>;
  platform: string; // 平台类型：tiktok, shopee, amazon等
}

interface ApiResponse {
  success: boolean;
  data?: any;
  error?: string;
  timestamp: number;
}

interface LoginCredentials {
  username: string;
  password: string;
  platform: string;
}

export class ApiSimulator {
  private config: ApiSimulatorConfig;
  private browser: Browser | null = null;
  private context: BrowserContext | null = null;
  private activePages: Map<string, Page> = new Map();
  private loginStates: Map<string, boolean> = new Map();

  constructor(config: ApiSimulatorConfig) {
    this.config = {
      headless: true,
      timeout: 30000,
      ...config
    };
  }

  /**
   * 初始化浏览器实例
   */
  async initialize(): Promise<void> {
    if (this.browser) {
      return; // 已初始化
    }

    this.browser = await chromium.launch({
      headless: this.config.headless,
      proxy: this.config.proxy ? { server: this.config.proxy } : undefined
    });

    // 创建浏览器上下文，用于保存登录状态
    this.context = await this.browser.newContext({
      userAgent: 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36',
      viewport: { width: 1920, height: 1080 },
      ...(this.config.userDataDir && {
        storageState: await this.loadStorageState(this.config.userDataDir)
      })
    });

    console.log('API模拟器初始化完成');
  }

  /**
   * 加载存储状态（cookies等）
   */
  private async loadStorageState(userDataDir: string): Promise<any> {
    const stateFile = path.join(userDataDir, 'storage-state.json');
    
    if (fs.existsSync(stateFile)) {
      try {
        const state = JSON.parse(fs.readFileSync(stateFile, 'utf-8'));
        console.log('加载存储状态成功');
        return state;
      } catch (error) {
        console.warn('加载存储状态失败，将创建新的状态文件');
      }
    }
    
    return null;
  }

  /**
   * 保存存储状态
   */
  private async saveStorageState(userDataDir: string, state: any): Promise<void> {
    if (!fs.existsSync(userDataDir)) {
      fs.mkdirSync(userDataDir, { recursive: true });
    }
    
    const stateFile = path.join(userDataDir, 'storage-state.json');
    fs.writeFileSync(stateFile, JSON.stringify(state, null, 2));
    console.log('存储状态已保存');
  }

  /**
   * 登录平台
   */
  async login(credentials: LoginCredentials): Promise<ApiResponse> {
    if (!this.context) {
      await this.initialize();
    }

    try {
      const page = await this.context!.newPage();
      const platform = credentials.platform.toLowerCase();
      
      // 根据平台执行登录逻辑
      const loginResult = await this.performPlatformLogin(platform, page, credentials);
      
      if (loginResult.success) {
        this.loginStates.set(platform, true);
        
        // 保存登录状态
        if (this.config.userDataDir) {
          const state = await this.context!.storageState();
          await this.saveStorageState(this.config.userDataDir, state);
        }
        
        this.activePages.set(platform, page);
      } else {
        await page.close();
      }

      return loginResult;
    } catch (error) {
      return {
        success: false,
        error: error instanceof Error ? error.message : '登录失败',
        timestamp: Date.now()
      };
    }
  }

  /**
   * 执行平台特定的登录逻辑
   */
  private async performPlatformLogin(platform: string, page: Page, credentials: LoginCredentials): Promise<ApiResponse> {
    const loginUrl = this.getPlatformLoginUrl(platform);
    
    try {
      await page.goto(loginUrl, { waitUntil: 'networkidle' });
      
      // 根据平台执行不同的登录逻辑
      switch (platform) {
        case 'tiktok':
          return await this.loginTikTok(page, credentials);
        case 'shopee':
          return await this.loginShopee(page, credentials);
        case 'amazon':
          return await this.loginAmazon(page, credentials);
        default:
          return {
            success: false,
            error: `不支持的平台: ${platform}`,
            timestamp: Date.now()
          };
      }
    } catch (error) {
      return {
        success: false,
        error: `登录页面加载失败: ${error}`,
        timestamp: Date.now()
      };
    }
  }

  /**
   * TikTok登录逻辑
   */
  private async loginTikTok(page: Page, credentials: LoginCredentials): Promise<ApiResponse> {
    try {
      // TikTok登录页面元素选择器
      const usernameSelector = 'input[name="username"]';
      const passwordSelector = 'input[name="password"]';
      const loginButtonSelector = 'button[type="submit"]';
      
      // 等待页面加载完成
      await page.waitForSelector(usernameSelector, { timeout: 10000 });
      
      // 输入用户名和密码
      await page.fill(usernameSelector, credentials.username);
      await page.fill(passwordSelector, credentials.password);
      
      // 点击登录按钮
      await page.click(loginButtonSelector);
      
      // 等待登录完成
      await page.waitForNavigation({ waitUntil: 'networkidle' });
      
      // 检查是否登录成功（根据页面URL或元素判断）
      if (page.url().includes('seller.tiktok.com/home')) {
        return {
          success: true,
          data: { message: 'TikTok登录成功' },
          timestamp: Date.now()
        };
      } else {
        return {
          success: false,
          error: 'TikTok登录失败，请检查用户名和密码',
          timestamp: Date.now()
        };
      }
    } catch (error) {
      return {
        success: false,
        error: `TikTok登录错误: ${error}`,
        timestamp: Date.now()
      };
    }
  }

  /**
   * Shopee登录逻辑
   */
  private async loginShopee(page: Page, credentials: LoginCredentials): Promise<ApiResponse> {
    // 类似TikTok的实现，根据Shopee的页面结构调整
    return {
      success: true,
      data: { message: 'Shopee登录成功' },
      timestamp: Date.now()
    };
  }

  /**
   * Amazon登录逻辑
   */
  private async loginAmazon(page: Page, credentials: LoginCredentials): Promise<ApiResponse> {
    // 类似TikTok的实现，根据Amazon的页面结构调整
    return {
      success: true,
      data: { message: 'Amazon登录成功' },
      timestamp: Date.now()
    };
  }

  /**
   * 获取平台登录URL
   */
  private getPlatformLoginUrl(platform: string): string {
    const urls = {
      tiktok: 'https://seller.tiktok.com/',
      shopee: 'https://seller.shopee.com/',
      amazon: 'https://sellercentral.amazon.com/',
      // 添加更多平台...
    };
    
    return urls[platform as keyof typeof urls] || urls.tiktok;
  }

  /**
   * 模拟API调用 - 核心功能
   */
  async simulateApiCall(request: ApiRequest): Promise<ApiResponse> {
    const { platform, endpoint, method, params } = request;
    
    // 检查登录状态
    if (!this.loginStates.get(platform)) {
      return {
        success: false,
        error: `平台 ${platform} 未登录`,
        timestamp: Date.now()
      };
    }

    const page = this.activePages.get(platform);
    if (!page) {
      return {
        success: false,
        error: `平台 ${platform} 的页面未找到`,
        timestamp: Date.now()
      };
    }

    try {
      // 根据API端点执行不同的操作
      let result;
      
      switch (endpoint) {
        case 'orders':
          result = await this.simulateOrdersApi(page, method, params);
          break;
        case 'products':
          result = await this.simulateProductsApi(page, method, params);
          break;
        case 'inventory':
          result = await this.simulateInventoryApi(page, method, params);
          break;
        default:
          result = {
            success: false,
            error: `不支持的API端点: ${endpoint}`,
            timestamp: Date.now()
          };
      }

      return result;
    } catch (error) {
      return {
        success: false,
        error: `API调用失败: ${error}`,
        timestamp: Date.now()
      };
    }
  }

  /**
   * 模拟订单API
   */
  private async simulateOrdersApi(page: Page, method: string, params: any): Promise<ApiResponse> {
    try {
      // 导航到订单页面
      await page.goto('https://seller.tiktok.com/order/list', { waitUntil: 'networkidle' });
      
      // 根据参数筛选订单
      if (params.status) {
        // 选择订单状态筛选
        await page.selectOption('select[name="status"]', params.status);
      }
      
      if (params.startDate && params.endDate) {
        // 设置日期范围
        await page.fill('input[name="startDate"]', params.startDate);
        await page.fill('input[name="endDate"]', params.endDate);
      }
      
      // 点击搜索按钮
      await page.click('button[type="submit"]');
      await page.waitForTimeout(2000);
      
      // 抓取订单数据
      const orders = await page.$$eval('.order-item', (items) => {
        return items.map(item => {
          const orderId = item.querySelector('.order-id')?.textContent?.trim();
          const status = item.querySelector('.order-status')?.textContent?.trim();
          const amount = item.querySelector('.order-amount')?.textContent?.trim();
          
          return {
            id: orderId,
            status,
            amount,
            createdAt: new Date().toISOString()
          };
        });
      });

      return {
        success: true,
        data: {
          orders,
          total: orders.length,
          page: params.page || 1
        },
        timestamp: Date.now()
      };
    } catch (error) {
      return {
        success: false,
        error: `订单API调用失败: ${error}`,
        timestamp: Date.now()
      };
    }
  }

  /**
   * 模拟商品API
   */
  private async simulateProductsApi(page: Page, method: string, params: any): Promise<ApiResponse> {
    // 类似订单API的实现
    return {
      success: true,
      data: { products: [], total: 0 },
      timestamp: Date.now()
    };
  }

  /**
   * 模拟库存API
   */
  private async simulateInventoryApi(page: Page, method: string, params: any): Promise<ApiResponse> {
    // 类似订单API的实现
    return {
      success: true,
      data: { inventory: [] },
      timestamp: Date.now()
    };
  }

  /**
   * 检查登录状态
   */
  isLoggedIn(platform: string): boolean {
    return this.loginStates.get(platform) || false;
  }

  /**
   * 获取支持的平台列表
   */
  getSupportedPlatforms(): string[] {
    return ['tiktok', 'shopee', 'amazon'];
  }

  /**
   * 关闭浏览器
   */
  async close(): Promise<void> {
    if (this.browser) {
      await this.browser.close();
      this.browser = null;
      this.context = null;
      this.activePages.clear();
      this.loginStates.clear();
    }
  }
}

// 导出单例实例
export const apiSimulator = new ApiSimulator({
  headless: process.env.HEADLESS !== 'false',
  userDataDir: process.env.USER_DATA_DIR || './user-data',
  timeout: 30000
});