/**
 * 统一任务执行器
 *
 * 功能：
 * - try/catch 包裹每个任务
 * - 自动记录开始/结束/失败日志
 * - 单任务失败不影响其他任务
 */

const logger = require('./logger');
const config = require('../config');
const { safeGoto } = require('./page');

function withTimeout(promise, timeoutMs, taskName) {
  let timer = null;
  const timeout = new Promise((_, reject) => {
    timer = setTimeout(() => {
      reject(new Error(`${taskName} 单任务超时 ${timeoutMs}ms`));
    }, timeoutMs);
  });

  return Promise.race([promise, timeout]).finally(() => {
    if (timer) clearTimeout(timer);
  });
}

async function prepareRetry(page, taskName, attempt) {
  logger.info(`  → ${taskName} 准备第${attempt}次重试，回到积分中心...`);
  await safeGoto(page, config.urls.points, {
    label: '积分中心',
    timeout: config.navigationTimeout,
    waitFor: ['.g-user-avatar', '.novice-task-item-box'],
  }).catch((err) => {
    logger.warn(`  → 重试前刷新积分中心失败: ${err.message}`);
  });
  await page.waitForTimeout(1000).catch(() => {});
}

/**
 * 执行任务（带防护）
 *
 * @param {string} taskName - 任务显示名称（如 "每日Star"）
 * @param {Function} handler - 异步任务函数 async (page) => { ... }
 * @param {import('playwright').Page} page - 当前页面
 * @returns {Promise<boolean>} 任务是否成功
 */
async function runTask(taskName, handler, page) {
  logger.divider();
  logger.info(`开始执行任务: ${taskName}`);

  const maxAttempts = Math.max(1, Number(config.retryCount) || 1);
  let lastError = null;

  for (let attempt = 1; attempt <= maxAttempts; attempt++) {
    if (attempt > 1) {
      await prepareRetry(page, taskName, attempt);
    }

    try {
      logger.info(`  → ${taskName} 第${attempt}/${maxAttempts}次尝试`);
      await withTimeout(handler(page), config.taskTimeout, taskName);
      logger.info(`✅ ${taskName} 执行成功`);
      return true;
    } catch (err) {
      lastError = err;
      if (attempt < maxAttempts) {
        logger.warn(`⚠️ ${taskName} 第${attempt}/${maxAttempts}次失败: ${err.message}`);
      } else {
        logger.error(`❌ ${taskName} 执行失败: ${err.message}`);
      }
    }
  }

  if (lastError && lastError.stack) {
    logger.warn(lastError.stack);
  }
  return false;
}

/**
 * 批量执行任务列表
 *
 * @param {import('playwright').Page} page - 主页面
 * @param {Array<{name: string, handler: Function}>} tasks - 任务列表
 * @returns {Promise<Object<string, boolean>>} 任务名 → 是否成功
 */
async function runTasks(page, tasks) {
  const results = {};

  for (const { name, handler } of tasks) {
    results[name] = await runTask(name, handler, page);
  }

  return results;
}

module.exports = {
  runTask,
  runTasks,
};