import { NextRequest, NextResponse } from 'next/server';
import type { OAuthCallbackParams } from '@/app/types/google-oauth';

/**
 * Google OAuth回调处理API
 * 处理从Google OAuth返回的授权码，完成用户认证
 */
export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const { code, state, inviteCode } = body;

    // 验证必需参数
    if (!code || !state) {
      return NextResponse.json(
        { 
          success: false, 
          message: 'Missing required parameters: code and state' 
        },
        { status: 400 }
      );
    }

    // 解析state参数
    let stateData: any = {};
    try {
      stateData = JSON.parse(state);
    } catch (e) {
      console.warn('无法解析state参数:', state);
      return NextResponse.json(
        { 
          success: false, 
          message: 'Invalid state parameter' 
        },
        { status: 400 }
      );
    }

    console.log('Google OAuth回调处理开始:', {
      codeLength: code.length,
      stateData,
      inviteCode
    });

    // 第一步：使用authorization code向Google换取access token和id_token
    const googleClientId = '847079918888-o1nne8d3ij80dn20qurivo987pv07225.apps.googleusercontent.com';
    const googleClientSecret = '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'; // 需要设置环境变量
    
    if (!googleClientSecret) {
      console.error('Google Client Secret未配置');
      return NextResponse.json(
        {
          success: false,
          message: 'Google Client Secret not configured'
        },
        { status: 500 }
      );
    }

    const tokenResponse = await fetch('https://oauth2.googleapis.com/token', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
      },
      body: new URLSearchParams({
        code,
        client_id: googleClientId,
        client_secret: googleClientSecret,
        redirect_uri: getRedirectUri(request),
        grant_type: 'authorization_code',
      }),
    });

    if (!tokenResponse.ok) {
      const errorText = await tokenResponse.text();
      console.error('Google token exchange failed:', errorText);
      return NextResponse.json(
        {
          success: false,
          message: 'Failed to exchange authorization code for tokens'
        },
        { status: 400 }
      );
    }

    const tokenData = await tokenResponse.json();
    const { id_token } = tokenData;

    if (!id_token) {
      console.error('No id_token received from Google');
      return NextResponse.json(
        {
          success: false,
          message: 'No id_token received from Google'
        },
        { status: 400 }
      );
    }

    // 第二步：使用id_token调用Java后端
    const javaBaseUrl = process.env.NEXT_PUBLIC_JAVA_URL || 'https://77.app.java.auth.qikongjian.com';
    
    const backendResponse = await fetch(`${javaBaseUrl}/api/auth/google/login`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json',
      },
      body: JSON.stringify({
        idToken: id_token, // 使用从Google获取的id_token
        action: 'auto', // 自动判断登录或注册
        inviteCode: inviteCode || stateData.inviteCode || undefined
      })
    });

    const backendResult = await backendResponse.json();

    if (!backendResponse.ok || !backendResult.success) {
      console.error('Java后端处理Google OAuth失败:', backendResult);
      return NextResponse.json(
        {
          success: false,
          message: backendResult.message || 'Google authentication failed'
        },
        { status: backendResponse.status || 500 }
      );
    }

    console.log('Google OAuth认证成功:', {
      userId: backendResult.data?.user?.userId,
      email: backendResult.data?.user?.email
    });

    // 返回成功结果
    return NextResponse.json({
      success: true,
      data: {
        token: backendResult.data.token,
        user: backendResult.data.userInfo || backendResult.data.user,
        message: 'Google authentication successful'
      }
    });

  } catch (error: any) {
    console.error('Google OAuth回调处理错误:', error);
    
    return NextResponse.json(
      {
        success: false,
        message: error.message || 'Internal server error during Google OAuth callback'
      },
      { status: 500 }
    );
  }
}

/**
 * 根据请求获取正确的redirect_uri
 */
function getRedirectUri(request: NextRequest): string {
  const host = request.headers.get('host') || '';
  const protocol = request.headers.get('x-forwarded-proto') || 'https';
  
  if (host.includes('localhost') || host.includes('127.0.0.1')) {
    return `${protocol}://${host}/api/auth/google/callback`;
  } else if (host.includes('movieflow.net')) {
    return 'https://www.movieflow.net/api/auth/google/callback';
  } else if (host.includes('movieflow.ai')) {
    return 'https://www.movieflow.ai/api/auth/google/callback';
  } else {
    // 默认使用生产环境
    return 'https://www.movieflow.ai/api/auth/google/callback';
  }
}

/**
 * 处理GET请求（如果需要）
 */
export async function GET(request: NextRequest) {
  return NextResponse.json(
    { 
      success: false, 
      message: 'This endpoint only accepts POST requests' 
    },
    { status: 405 }
  );
}