const BaseAction = require('../core/base-action');
const SmartSelector = require('../core/smart-selector');

/**
 * 点击动作
 */
class ClickAction extends BaseAction {
  async execute() {
    const selector = this.config.selector || this.config.find;
    
    if (!selector) {
      throw new Error('缺少选择器配置');
    }
    
    this.log('info', '执行点击');
    
    // 查找元素
    const smartSelector = SmartSelector.fromConfig(selector, this.page);
    const element = await smartSelector.find(this.config.timeout || 10000);
    
    if (!element) {
      throw new Error(`无法找到元素: ${JSON.stringify(selector)}`);
    }
    
    // 滚动到可视区域
    await element.evaluate((el) => {
      el.scrollIntoView({ behavior: 'smooth', block: 'center' });
    });
    
    await new Promise(resolve => setTimeout(resolve, 300));
    
    // 点击
    await element.click();
    
    this.log('debug', '✓ 点击完成');
    
    // 验证点击后的变化（新元素出现 / 旧元素消失）
    if (this.config.verifyAfter) {
      await this.verifyAfterClick(this.config.verifyAfter);
    }
    
    // 等待页面变化（如果配置了）
    if (this.config.waitForPageChange) {
      await this.waitForPageChange(this.config.checkSelector);
    }
    
    // 可选的等待时间
    if (this.config.waitAfter) {
      await new Promise(resolve => setTimeout(resolve, this.config.waitAfter));
    }
    
    return { success: true };
  }
  
  /**
   * 验证点击后的变化
   */
  async verifyAfterClick(config) {
    const { appears, disappears, timeout = 10000 } = config;
    
    // 验证新元素出现
    if (appears) {
      this.log('debug', '验证新元素出现...');
      for (const selector of (Array.isArray(appears) ? appears : [appears])) {
        try {
          await this.page.waitForSelector(selector, { timeout, visible: true });
          this.log('debug', `✓ 新元素已出现: ${selector}`);
        } catch (error) {
          throw new Error(`点击后验证失败: 元素 "${selector}" 未出现`);
        }
      }
    }
    
    // 验证旧元素消失
    if (disappears) {
      this.log('debug', '验证旧元素消失...');
      for (const selector of (Array.isArray(disappears) ? disappears : [disappears])) {
        try {
          await this.page.waitForSelector(selector, { timeout, hidden: true });
          this.log('debug', `✓ 旧元素已消失: ${selector}`);
        } catch (error) {
          throw new Error(`点击后验证失败: 元素 "${selector}" 未消失`);
        }
      }
    }
  }
  
  /**
   * 等待页面内容变化
   */
  async waitForPageChange(checkSelector, timeout = 15000) {
    this.log('debug', '等待页面变化...');
    
    const startTime = Date.now();
    const initialUrl = this.page.url();
    
    while (Date.now() - startTime < timeout) {
      // 检查 URL 是否变化
      if (this.page.url() !== initialUrl) {
        this.log('debug', '✓ URL 已变化');
        return true;
      }
      
      // 检查特定元素是否出现
      if (checkSelector) {
        const smartSelector = SmartSelector.fromConfig(checkSelector, this.page);
        const newElement = await smartSelector.find(1000);
        if (newElement) {
          this.log('debug', '✓ 页面内容已变化');
          return true;
        }
      }
      
      await new Promise(resolve => setTimeout(resolve, 500));
    }
    
    this.log('warn', '等待页面变化超时');
    return false;
  }
}

module.exports = ClickAction;