// =====================================================
// 資料庫狀態監控 API
// =====================================================

import { NextRequest, NextResponse } from 'next/server';
import { db } from '@/lib/database';

export async function GET(request: NextRequest) {
  try {
    // 獲取備援狀態
    const failoverStatus = db.getFailoverStatus();
    
    if (!failoverStatus) {
      return NextResponse.json({
        success: false,
        message: '備援功能未啟用',
        data: null
      });
    }

    // 獲取詳細狀態信息
    const status = {
      isEnabled: failoverStatus.isEnabled,
      currentDatabase: failoverStatus.currentDatabase,
      masterHealthy: failoverStatus.masterHealthy,
      slaveHealthy: failoverStatus.slaveHealthy,
      lastHealthCheck: failoverStatus.lastHealthCheck && failoverStatus.lastHealthCheck > 0 
        ? new Date(failoverStatus.lastHealthCheck).toISOString()
        : new Date().toISOString(), // 如果沒有健康檢查記錄，使用當前時間
      consecutiveFailures: failoverStatus.consecutiveFailures,
      uptime: process.uptime(),
      timestamp: new Date().toISOString()
    };

    return NextResponse.json({
      success: true,
      message: '資料庫狀態獲取成功',
      data: status
    });

  } catch (error) {
    console.error('獲取資料庫狀態失敗:', error);
    return NextResponse.json({
      success: false,
      message: '獲取資料庫狀態失敗',
      error: error instanceof Error ? error.message : '未知錯誤'
    }, { status: 500 });
  }
}

export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const { action, database } = body;

    if (action === 'switch') {
      if (!database || !['master', 'slave'].includes(database)) {
        return NextResponse.json({
          success: false,
          message: '無效的資料庫參數'
        }, { status: 400 });
      }

      const success = await db.switchDatabase(database as 'master' | 'slave');
      
      if (success) {
        return NextResponse.json({
          success: true,
          message: `已切換到 ${database} 資料庫`
        });
      } else {
        return NextResponse.json({
          success: false,
          message: `切換到 ${database} 資料庫失敗`
        }, { status: 400 });
      }
    }

    return NextResponse.json({
      success: false,
      message: '無效的操作'
    }, { status: 400 });

  } catch (error) {
    console.error('執行資料庫操作失敗:', error);
    return NextResponse.json({
      success: false,
      message: '執行資料庫操作失敗',
      error: error instanceof Error ? error.message : '未知錯誤'
    }, { status: 500 });
  }
}