/**
 * 修复标签覆盖率统计
 * 更新所有标签的coverage和coverage_rate字段
 */

const { getDb } = require('../db/init');

function updateTagStats(dbSuffix = 'onion') {
  const db = getDb(dbSuffix);
  
  try {
    // 获取总用户数
    const totalUsersRow = db.prepare('SELECT COUNT(*) as n FROM users').get();
    const totalUsers = totalUsersRow.n;
    
    if (totalUsers === 0) {
      console.error('❌ 没有用户数据');
      return;
    }
    
    console.log(`\n🔄 更新标签覆盖率统计（总用户数: ${totalUsers}）`);
    
    // 获取所有标签
    const tags = db.prepare('SELECT id FROM tags').all();
    
    let updated = 0;
    const stmt = db.prepare(`
      UPDATE tags SET coverage = ?, coverage_rate = ? WHERE id = ?
    `);
    
    for (const tag of tags) {
      // 计算该标签的覆盖用户数
      const coverageRow = db.prepare(`
        SELECT COUNT(DISTINCT user_id) as cnt FROM user_tags WHERE tag_id = ?
      `).get(tag.id);
      
      const coverage = coverageRow.cnt || 0;
      const coverage_rate = totalUsers > 0 ? +(coverage / totalUsers * 100).toFixed(2) : 0;
      
      stmt.run(coverage, coverage_rate, tag.id);
      updated++;
      
      if (updated % 50 === 0) {
        console.log(`  ✓ 已更新 ${updated} 个标签...`);
      }
    }
    
    console.log(`\n✅ 更新完成: ${updated} 个标签\n`);
    
    // 显示样本
    console.log('📊 样本数据（前5个标签）:');
    const samples = db.prepare(`
      SELECT id, name, coverage, coverage_rate FROM tags LIMIT 5
    `).all();
    
    for (const sample of samples) {
      console.log(`  • ${sample.name}: ${sample.coverage} users (${sample.coverage_rate}%)`);
    }
    
    // 显示统计
    console.log('\n📊 整体统计:');
    const stats = db.prepare(`
      SELECT 
        MIN(coverage) as min_coverage,
        MAX(coverage) as max_coverage,
        ROUND(AVG(coverage), 2) as avg_coverage,
        COUNT(*) as total_tags
      FROM tags
    `).get();
    
    console.log(`  • 总标签数: ${stats.total_tags}`);
    console.log(`  • 覆盖范围: ${stats.min_coverage} - ${stats.max_coverage} 用户`);
    console.log(`  • 平均覆盖: ${stats.avg_coverage} 用户`);
    
    db.close();
  } catch (e) {
    console.error('❌ 错误:', e.message);
    db.close();
    process.exit(1);
  }
}

// 执行更新
updateTagStats();