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 { searchParams } = new URL(request.url);
    const folder = searchParams.get('folder');
    
    if (!folder) {
      return NextResponse.json({ error: 'Folder parameter is required' }, { status: 400 });
    }

    const session = await getServerSession(authOptions);
    if (!session?.user) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }

    const nextcloudUrl = process.env.NEXTCLOUD_URL;
    const username = `cube-${session.user.id}`;
    
    // Get credentials without logging
    const credentials = await prisma.webDAVCredentials.findUnique({
      where: { userId: session.user.id }
    });

    if (!credentials) {
      return NextResponse.json({ error: 'Nextcloud credentials not found' }, { status: 404 });
    }

    const path = `/files/${username}/Private/${folder}`;
    
    // Make request without logging sensitive information
    const response = await fetch(`${nextcloudUrl}/remote.php/dav${path}`, {
      method: 'PROPFIND',
      headers: {
        'Authorization': `Basic ${Buffer.from(`${username}:${credentials.password}`).toString('base64')}`,
        'Depth': '1',
        'Content-Type': 'application/xml',
      },
      body: '<?xml version="1.0" encoding="UTF-8"?><d:propfind xmlns:d="DAV:"><d:prop><d:resourcetype/><d:getlastmodified/><d:getcontentlength/><d:getcontenttype/><d:getetag/></d:prop></d:propfind>',
    });

    if (!response.ok) {
      return NextResponse.json({ error: 'Failed to fetch files' }, { status: response.status });
    }

    const text = await response.text();
    const parser = new DOMParser();
    const xmlDoc = parser.parseFromString(text, 'text/xml');
    
    const files: any[] = [];
    const responses = xmlDoc.getElementsByTagName('d:response');
    
    for (let i = 0; i < responses.length; i++) {
      const response = responses[i];
      const href = response.getElementsByTagName('d:href')[0]?.textContent;
      const propstat = response.getElementsByTagName('d:propstat')[0];
      
      if (href && propstat) {
        const prop = propstat.getElementsByTagName('d:prop')[0];
        if (prop) {
          const type = prop.getElementsByTagName('d:resourcetype')[0];
          const lastmod = prop.getElementsByTagName('d:getlastmodified')[0]?.textContent;
          const size = prop.getElementsByTagName('d:getcontentlength')[0]?.textContent;
          const mime = prop.getElementsByTagName('d:getcontenttype')[0]?.textContent;
          const etag = prop.getElementsByTagName('d:getetag')[0]?.textContent;
          
          if (type && !type.getElementsByTagName('d:collection').length) {
            const filename = href.split('/').pop() || '';
            files.push({
              filename: href,
              basename: filename,
              lastmod,
              size,
              type: 'file',
              etag,
              mime
            });
          }
        }
      }
    }

    return NextResponse.json(files);
  } catch (error) {
    // Log error without sensitive information
    console.error('Error fetching files:', error instanceof Error ? error.message : 'Unknown 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, mime } = 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 {
      // Use the provided path directly
      const path = id;
      console.log('Updating file at path:', path);
      
      // Set the correct content type based on file extension or provided mime type
      const contentType = mime || (title.endsWith('.vcf') ? 'text/vcard' : 'text/markdown');
      await client.putFileContents(path, content, { contentType });
      
      // Get the updated file details
      const fileDetails = await client.stat(path);
      
      return NextResponse.json({
        id: fileDetails.filename,
        title: fileDetails.basename,
        lastModified: new Date(fileDetails.lastmod).toISOString(),
        size: fileDetails.size,
        type: 'file',
        mime: fileDetails.mime,
        etag: fileDetails.etag
      });
    } catch (error) {
      console.error('Error updating file:', error);
      return NextResponse.json({ error: 'Failed to update file' }, { 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 });
  }
}