// =====================================================
// 連線測試 API - 驗證連線釋放
// =====================================================

import { NextRequest, NextResponse } from 'next/server';
import { connectionMonitor } from '@/lib/connection-monitor';

export async function GET(request: NextRequest) {
  try {
    // 獲取測試前的連線狀態
    const beforeStats = await connectionMonitor.getConnectionStats();
    
    // 執行一些測試查詢
    const testQueries = [
      'SELECT 1 as test1',
      'SELECT 2 as test2', 
      'SELECT 3 as test3',
      'SELECT COUNT(*) as user_count FROM users',
      'SELECT COUNT(*) as app_count FROM apps'
    ];
    
    console.log('🧪 開始連線測試...');
    console.log(`測試前連線數: ${beforeStats.activeConnections}`);
    
    // 執行測試查詢
    for (let i = 0; i < testQueries.length; i++) {
      const { db } = await import('@/lib/database');
      await db.query(testQueries[i]);
      console.log(`✅ 完成測試查詢 ${i + 1}`);
    }
    
    // 等待一小段時間讓連線釋放
    await new Promise(resolve => setTimeout(resolve, 1000));
    
    // 獲取測試後的連線狀態
    const afterStats = await connectionMonitor.getConnectionStats();
    
    console.log(`測試後連線數: ${afterStats.activeConnections}`);
    
    return NextResponse.json({
      success: true,
      message: '連線測試完成',
      data: {
        before: {
          activeConnections: beforeStats.activeConnections,
          usagePercentage: beforeStats.usagePercentage
        },
        after: {
          activeConnections: afterStats.activeConnections,
          usagePercentage: afterStats.usagePercentage
        },
        difference: {
          connectionChange: afterStats.activeConnections - beforeStats.activeConnections,
          isReleased: afterStats.activeConnections <= beforeStats.activeConnections
        }
      }
    });

  } catch (error) {
    console.error('連線測試失敗:', error);
    return NextResponse.json({
      success: false,
      message: '連線測試失敗',
      error: error instanceof Error ? error.message : '未知錯誤'
    }, { status: 500 });
  }
}