import { NextResponse } from 'next/server';
import { getAdminAuth, getAdminDb } from '@/lib/firebase/admin';

/**
 * Fetch user's GitHub repositories
 */
export async function GET(request: Request) {
  try {
    const authHeader = request.headers.get('Authorization');
    if (!authHeader?.startsWith('Bearer ')) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }

    const idToken = authHeader.split('Bearer ')[1];
    const adminAuth = getAdminAuth();
    const adminDb = getAdminDb();

    let userId: string;
    try {
      const decodedToken = await adminAuth.verifyIdToken(idToken);
      userId = decodedToken.uid;
    } catch (error) {
      return NextResponse.json({ error: 'Invalid token' }, { status: 401 });
    }

    // Get GitHub connection
    const connectionDoc = await adminDb
      .collection('githubConnections')
      .doc(userId)
      .get();

    if (!connectionDoc.exists) {
      return NextResponse.json(
        { error: 'GitHub not connected' },
        { status: 404 }
      );
    }

    const connection = connectionDoc.data()!;
    const accessToken = connection.accessToken; // TODO: Decrypt

    // Fetch repos from GitHub API
    const response = await fetch('https://api.github.com/user/repos?sort=updated&per_page=100', {
      headers: {
        Authorization: `Bearer ${accessToken}`,
        Accept: 'application/vnd.github.v3+json',
      },
    });

    if (!response.ok) {
      throw new Error('Failed to fetch repositories from GitHub');
    }

    const repos = await response.json();

    // Return simplified repo data
    return NextResponse.json(
      repos.map((repo: any) => ({
        id: repo.id,
        name: repo.name,
        full_name: repo.full_name,
        description: repo.description,
        html_url: repo.html_url,
        language: repo.language,
        default_branch: repo.default_branch,
        private: repo.private,
        topics: repo.topics || [],
        updated_at: repo.updated_at,
      }))
    );
  } catch (error) {
    console.error('[GitHub Repos] Error:', error);
    return NextResponse.json(
      { error: 'Failed to fetch repositories' },
      { status: 500 }
    );
  }
}