import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { PrismaClient } from '@prisma/client';
import { authOptions } from '@/app/api/auth/[...nextauth]/route';
import { createClient } from 'webdav';

// Use a single PrismaClient instance
declare global {
  var prisma: PrismaClient | undefined;
}

const prisma = global.prisma || new PrismaClient();
if (process.env.NODE_ENV !== 'production') global.prisma = prisma;

// Helper function to create WebDAV client
const createWebDAVClient = async (userId: string) => {
  const credentials = await prisma.webDAVCredentials.findUnique({
    where: { userId },
  });

  if (!credentials) {
    throw new Error('No WebDAV credentials found');
  }

  const baseURL = process.env.NEXTCLOUD_URL;
  if (!baseURL) {
    throw new Error('NEXTCLOUD_URL environment variable is not set');
  }

  const normalizedBaseURL = baseURL.endsWith('/') ? baseURL.slice(0, -1) : baseURL;
  const webdavURL = `${normalizedBaseURL}/remote.php/dav`;
  
  return {
    client: createClient(webdavURL, {
      username: credentials.username,
      password: credentials.password,
      authType: 'password',
    }),
    username: credentials.username
  };
};

export async function GET(request: Request) {
  try {
    const session = await getServerSession(authOptions);
    if (!session?.user?.id) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }

    const { searchParams } = new URL(request.url);
    const id = searchParams.get('id');

    if (!id) {
      return NextResponse.json({ error: 'Note ID is required' }, { status: 400 });
    }

    const { client } = await createWebDAVClient(session.user.id);
    
    try {
      const content = await client.getFileContents(id, { format: 'text' });
      return NextResponse.json({ content });
    } catch (error) {
      console.error('Error fetching note content:', error);
      return NextResponse.json({ error: 'Failed to fetch note content' }, { status: 500 });
    }
  } catch (error) {
    console.error('Error in GET request:', error);
    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
  }
}