import * as puppeteer from 'puppeteer';
import { Logger } from '@nestjs/common';

// 模拟人类鼠标移动
async function simulateHumanMouseMovement(page: puppeteer.Page) {
  const viewport = page.viewport();
  if (!viewport) return;

  const movements = 5 + Math.floor(Math.random() * 5); // 5-10次随机移动

  for (let i = 0; i < movements; i++) {
    const x = Math.floor(Math.random() * viewport.width);
    const y = Math.floor(Math.random() * viewport.height);

    await page.mouse.move(x, y, {
      steps: 10 + Math.floor(Math.random() * 20) // 10-30步，使移动更平滑
    });

    // 随机停顿 100-500ms
    await new Promise(r => setTimeout(r, 100 + Math.random() * 400));
  }
}

// 模拟人类滚动
async function simulateHumanScrolling(page: puppeteer.Page) {
  const scrollCount = 3 + Math.floor(Math.random() * 5); // 3-7次滚动

  for (let i = 0; i < scrollCount; i++) {
    const scrollDistance = 100 + Math.floor(Math.random() * 400); // 100-500px

    await page.evaluate((distance) => {
      window.scrollBy({
        top: distance,
        behavior: 'smooth'
      });
    }, scrollDistance);

    // 随机停顿 500-1500ms
    await new Promise(r => setTimeout(r, 500 + Math.random() * 1000));
  }

  // 滚动回顶部
  await page.evaluate(() => {
    window.scrollTo({ top: 0, behavior: 'smooth' });
  });
  await new Promise(r => setTimeout(r, 1000));
}

export interface CdtResult {
  title: string;
  publishDate: Date;
  url: string;
}

export const CdtCrawler = {
  name: '中国大唐集团电子商务平台',
  url: 'https://tang.cdt-ec.com/home/index.html',
  baseUrl: 'https://tang.cdt-ec.com',

  async crawl(browser: puppeteer.Browser): Promise<CdtResult[]> {
    const logger = new Logger('CdtCrawler');
    const page = await browser.newPage();

    const username = process.env.PROXY_USERNAME;
    const password = process.env.PROXY_PASSWORD;
    if (username && password) {
      await page.authenticate({ username, password });
    }

    await page.setUserAgent('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36');

    const allResults: CdtResult[] = [];
    let currentPage = 1;
    const maxPages = 5;

    try {
      logger.log(`Navigating to ${this.url}...`);
      await page.goto(this.url, { waitUntil: 'networkidle2', timeout: 60000 });

      // 模拟人类行为
      logger.log('Simulating human mouse movements...');
      await simulateHumanMouseMovement(page);

      logger.log('Simulating human scrolling...');
      await simulateHumanScrolling(page);

      // 点击"招标公告"标签
      logger.log('Looking for "招标公告" tab...');
      await page.waitForFunction(() => {
        const tabs = Array.from(document.querySelectorAll('span.notice-tab'));
        return tabs.some(tab => tab.textContent && tab.textContent.includes('招标公告'));
      }, { timeout: 60000 });

      await page.evaluate(() => {
        const tabs = Array.from(document.querySelectorAll('span.notice-tab'));
        const target = tabs.find(tab => tab.textContent && tab.textContent.includes('招标公告')) as HTMLElement;
        if (target) target.click();
      });

      logger.log('Clicked "招标公告" tab.');
      await new Promise(r => setTimeout(r, 2000));

      // 模拟人类行为
      logger.log('Simulating human mouse movements...');
      await simulateHumanMouseMovement(page);

      logger.log('Simulating human scrolling...');
      await simulateHumanScrolling(page);

      // 点击"招标公告"下的"更多+"链接
      logger.log('Looking for "更多+" link under "招标公告"...');
      await page.waitForFunction(() => {
        const titles = Array.from(document.querySelectorAll('span.h-notice-title'));
        return titles.some(title => title.textContent && title.textContent.includes('招标公告'));
      }, { timeout: 30000 });

      await page.evaluate(() => {
        const titles = Array.from(document.querySelectorAll('span.h-notice-title'));
        const targetTitle = titles.find(title => title.textContent && title.textContent.includes('招标公告'));
        if (targetTitle) {
          const parent = targetTitle.parentElement;
          if (parent) {
            const moreLink = parent.querySelector('a.h-notice-more') as HTMLElement;
            if (moreLink) moreLink.click();
          }
        }
      });

      logger.log('Clicked "更多+" link under "招标公告".');
      await page.waitForNavigation({ waitUntil: 'networkidle2', timeout: 60000 }).catch(() => {});
      await new Promise(r => setTimeout(r, 3000));

      // 模拟人类行为
      logger.log('Simulating human mouse movements...');
      await simulateHumanMouseMovement(page);

      logger.log('Simulating human scrolling...');
      await simulateHumanScrolling(page);

      // 等待表格加载完成
      logger.log('Waiting for table to load...');
      await page.waitForSelector('table.layui-table', { timeout: 30000 });

      while (currentPage <= maxPages) {
        // 等待表格数据加载
        await page.waitForSelector('tbody tr', { timeout: 10000 });

        // 获取当前页面的 HTML 内容
        const content = await page.content();
        const pageResults = this.extract(content);

        if (pageResults.length === 0) {
          logger.warn(`No results found on page ${currentPage}, stopping.`);
          break;
        }

        allResults.push(...pageResults);
        logger.log(`Extracted ${pageResults.length} items from page ${currentPage}`);

        // 模拟人类行为 - 翻页前
        logger.log('Simulating human mouse movements before pagination...');
        await simulateHumanMouseMovement(page);

        logger.log('Simulating human scrolling before pagination...');
        await simulateHumanScrolling(page);

        // 查找下一页按钮
        const nextButtonSelector = 'a.layui-laypage-next:not(.layui-disabled)';
        const nextButtonExists = await page.evaluate((selector) => {
          const btn = document.querySelector(selector);
          return btn !== null && !btn.classList.contains('layui-disabled');
        }, nextButtonSelector);

        if (!nextButtonExists) {
          logger.log('Next page button not found or disabled. Reached end of list.');
          break;
        }

        logger.log(`Navigating to page ${currentPage + 1}...`);

        try {
          // 点击下一页按钮
          await page.evaluate((selector) => {
            const btn = document.querySelector(selector) as HTMLElement;
            if (btn) btn.click();
          }, nextButtonSelector);

          // 等待 AJAX 请求完成（通过监听网络请求）
          await page.waitForFunction(() => {
            // 检查表格是否正在加载
            const loading = document.querySelector('.layui-table-loading');
            return !loading;
          }, { timeout: 30000 }).catch(() => {});

          // 额外等待确保数据加载完成
          await new Promise(r => setTimeout(r, 2000));

          // 检查是否真的翻页了（通过检查当前页码）
          const currentActivePage = await page.evaluate(() => {
            const activeSpan = document.querySelector('.layui-laypage-curr em:last-child');
            return activeSpan ? parseInt(activeSpan.textContent || '1') : 1;
          });

          if (currentActivePage <= currentPage) {
            logger.log('Page did not change, stopping.');
            break;
          }

          currentPage++;

          // 模拟人类行为 - 翻页后
          logger.log('Simulating human mouse movements after pagination...');
          await simulateHumanMouseMovement(page);

          logger.log('Simulating human scrolling after pagination...');
          await simulateHumanScrolling(page);

          // Random delay between pages
          const delay = Math.floor(Math.random() * (3000 - 1000 + 1)) + 1000;
          await new Promise(resolve => setTimeout(resolve, delay));

        } catch (navError) {
          logger.error(`Navigation to page ${currentPage + 1} failed: ${navError.message}`);
          break;
        }
      }

      return allResults;

    } catch (error) {
      logger.error(`Failed to crawl ${this.name}: ${error.message}`);
      return allResults;
    } finally {
      await page.close();
    }
  },

  extract(html: string): CdtResult[] {
    const results: CdtResult[] = [];
    /**
     * Regex groups for tang.cdt-ec.com:
     * 1: URL
     * 2: Title (项目名称)
     * 3: Date (发布时间)
     */
    const regex = /<tr[^>]*data-index="[^"]*"[^>]*>[\s\S]*?<a[^>]*class="layui-table-link"[^>]*href="([^"]*)"[^>]*>([^<]*)<\/a>[\s\S]*?<td[^>]*data-field="publish_time"[^>]*>[\s\S]*?<div[^>]*class="layui-table-cell[^"]*"[^>]*>([^<]*)<\/div>[\s\S]*?<\/td>[\s\S]*?<\/tr>/gs;

    let match;
    while ((match = regex.exec(html)) !== null) {
      const url = match[1]?.trim();
      const title = match[2]?.trim();
      const dateStr = match[3]?.trim();

      if (title && url) {
        const fullUrl = url.startsWith('http') ? url : this.baseUrl + url;
        results.push({
          title,
          publishDate: dateStr ? new Date(dateStr) : new Date(),
          url: fullUrl.replace(/\/\//g, '/')
        });
      }
    }
    return results;
  }
};