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 folder = searchParams.get('folder') || 'Notes';

    const { client, username } = await createWebDAVClient(session.user.id);
    
    try {
      const path = `/files/${username}/Private/${folder}`;
      console.log('Fetching contents from path:', path);
      
      const files = await client.getDirectoryContents(path);
      console.log('Raw files response:', JSON.stringify(files, null, 2));

      const markdownFiles = files
        .filter((file: any) => file.basename.endsWith('.md'))
        .map((file: any) => ({
          id: file.filename,
          title: file.basename.replace('.md', ''),
          lastModified: new Date(file.lastmod).toISOString(),
          size: file.size,
          type: 'file',
          mime: file.mime,
          etag: file.etag
        }));

      return NextResponse.json(markdownFiles);
    } catch (error) {
      console.error('Error listing directory contents:', error);
      return NextResponse.json({ error: 'Failed to list directory contents' }, { status: 500 });
    }
  } catch (error) {
    console.error('Error fetching files:', error);
    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
  }
}

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

    const { title, content, folder } = await request.json();
    if (!title || !content || !folder) {
      return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
    }

    const { client, username } = await createWebDAVClient(session.user.id);
    
    try {
      const path = `/files/${username}/Private/${folder}/${title}.md`;
      console.log('Saving note to path:', path);
      
      await client.putFileContents(path, content);
      
      // Get the file details after saving
      const fileDetails = await client.stat(path);
      
      return NextResponse.json({
        id: fileDetails.filename,
        title: fileDetails.basename.replace('.md', ''),
        lastModified: new Date(fileDetails.lastmod).toISOString(),
        size: fileDetails.size,
        type: 'file',
        mime: fileDetails.mime,
        etag: fileDetails.etag
      });
    } catch (error) {
      console.error('Error saving note:', error);
      return NextResponse.json({ error: 'Failed to save note' }, { status: 500 });
    }
  } catch (error) {
    console.error('Error in POST request:', error);
    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
  }
}

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

    const { id, title, content, folder } = await request.json();
    if (!id || !title || !content || !folder) {
      return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
    }

    const { client, username } = await createWebDAVClient(session.user.id);
    
    try {
      const path = `/files/${username}/Private/${folder}/${title}.md`;
      console.log('Updating note at path:', path);
      
      await client.putFileContents(path, content);
      
      // Get the updated file details
      const fileDetails = await client.stat(path);
      
      return NextResponse.json({
        id: fileDetails.filename,
        title: fileDetails.basename.replace('.md', ''),
        lastModified: new Date(fileDetails.lastmod).toISOString(),
        size: fileDetails.size,
        type: 'file',
        mime: fileDetails.mime,
        etag: fileDetails.etag
      });
    } catch (error) {
      console.error('Error updating note:', error);
      return NextResponse.json({ error: 'Failed to update note' }, { status: 500 });
    }
  } catch (error) {
    console.error('Error in PUT request:', error);
    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
  }
}

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

    const { id, folder } = await request.json();
    if (!id || !folder) {
      return NextResponse.json({ error: 'Missing required fields' }, { status: 400 });
    }

    const { client, username } = await createWebDAVClient(session.user.id);
    
    try {
      const path = `/files/${username}/Private/${folder}/${id.split('/').pop()}`;
      console.log('Deleting note at path:', path);
      
      await client.deleteFile(path);
      
      return NextResponse.json({ success: true });
    } catch (error) {
      console.error('Error deleting note:', error);
      return NextResponse.json({ error: 'Failed to delete note' }, { status: 500 });
    }
  } catch (error) {
    console.error('Error in DELETE request:', error);
    return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
  }
}