import { NextResponse } from 'next/server';
import { auth } from '@/auth';
import { PrismaClient, Prisma } from '@/app/generated/prisma';
import { randomBytes } from 'crypto';

export async function GET(request: Request) {
  const session = await auth();
  if (!session) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
  }
  try {
    const { searchParams } = new URL(request.url);
    const handle = searchParams.get('handle');
    
    if (!handle) {
      return NextResponse.json({ error: '핸들이 필요합니다' }, { status: 400 });
    }

    const prisma = new PrismaClient();

    // 안전한 난수 기반 32자 코드 (충돌 확률 극히 낮음)
    const randomcode = randomBytes(16).toString('hex');

    // 중복 여부 확인 (email + handle 기준)
    const exists = await prisma.registerChannel.findFirst({
      where: {
        email: session.user?.email as string,
        handle: handle,
      },
      select: { id: true, randomcode: true },
    });
    if (exists) {
      return NextResponse.json(
        { error: '이미 등록된 요청입니다',  randomcode: exists.randomcode },
        { status: 409 }
      );
    }

    // DB에 저장
    const created = await prisma.registerChannel.create({
      data: {
        email: session.user?.email as string,
        handle: handle,
        randomcode: randomcode
      }
    });

    return NextResponse.json({ message: '성공', code: handle, randomcode: created.randomcode, id: created.id }, { status: 200 });
  } catch (error: unknown) {
    console.error('에러 발생:', error);

    // Prisma 에러 코드별 분기
    if (error instanceof Prisma.PrismaClientKnownRequestError) {
      // 고유 제약조건 위반 등
      if (error.code === 'P2002') {
        return NextResponse.json({ error: '중복된 값으로 저장할 수 없습니다' }, { status: 409 });
      }
      return NextResponse.json({ error: '요청이 올바르지 않습니다', code: error.code }, { status: 400 });
    }
    if (error instanceof Prisma.PrismaClientValidationError) {
      return NextResponse.json({ error: '유효하지 않은 데이터입니다' }, { status: 400 });
    }

    return NextResponse.json({ error: '서버 에러가 발생했습니다' }, { status: 500 });
  }
}