/**
 * GET /api/projects/[projectId]/file?path=apps/admin
 *
 * Returns directory listing or file content from the project's Gitea repo.
 * Response for directory: { type: "dir", items: [{ name, path, type }] }
 * Response for file:      { type: "file", content: string, encoding: "utf8" | "base64" }
 */
import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { authOptions } from '@/lib/auth/authOptions';
import { query } from '@/lib/db-postgres';

const GITEA_API_URL = process.env.GITEA_API_URL ?? 'https://git.vibnai.com';
const GITEA_API_TOKEN = process.env.GITEA_API_TOKEN ?? '';

async function giteaGet(path: string) {
  const res = await fetch(`${GITEA_API_URL}/api/v1${path}`, {
    headers: { Authorization: `token ${GITEA_API_TOKEN}` },
    next: { revalidate: 10 },
  });
  if (!res.ok) throw new Error(`Gitea ${res.status}: ${path}`);
  return res.json();
}

const BINARY_EXTENSIONS = new Set([
  'png', 'jpg', 'jpeg', 'gif', 'webp', 'svg', 'ico',
  'woff', 'woff2', 'ttf', 'eot',
  'zip', 'tar', 'gz', 'pdf',
]);

function isBinary(name: string): boolean {
  const ext = name.split('.').pop()?.toLowerCase() ?? '';
  return BINARY_EXTENSIONS.has(ext);
}

export async function GET(
  req: Request,
  { params }: { params: Promise<{ projectId: string }> }
) {
  try {
    const { projectId } = await params;
    const session = await getServerSession(authOptions);
    if (!session?.user?.email) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }

    const { searchParams } = new URL(req.url);
    const filePath = searchParams.get('path') ?? '';

    // Verify ownership + get giteaRepo
    const rows = await query<{ data: Record<string, unknown> }>(
      `SELECT p.data FROM fs_projects p
       JOIN fs_users u ON u.id = p.user_id
       WHERE p.id = $1 AND u.data->>'email' = $2 LIMIT 1`,
      [projectId, session.user.email]
    );
    if (rows.length === 0) {
      return NextResponse.json({ error: 'Project not found' }, { status: 404 });
    }

    const giteaRepo = rows[0].data?.giteaRepo as string | undefined;
    if (!giteaRepo) {
      return NextResponse.json({ error: 'No Gitea repo connected' }, { status: 404 });
    }

    const encodedPath = filePath ? encodeURIComponent(filePath).replace(/%2F/g, '/') : '';
    const apiPath = `/repos/${giteaRepo}/contents/${encodedPath}`;
    const data = await giteaGet(apiPath);

    // Directory listing
    if (Array.isArray(data)) {
      const items = data
        .map((item: { name: string; path: string; type: string; size?: number }) => ({
          name: item.name,
          path: item.path,
          type: item.type, // "file" | "dir" | "symlink"
          size: item.size,
        }))
        .sort((a, b) => {
          // Dirs first
          if (a.type === 'dir' && b.type !== 'dir') return -1;
          if (a.type !== 'dir' && b.type === 'dir') return 1;
          return a.name.localeCompare(b.name);
        });
      return NextResponse.json({ type: 'dir', items });
    }

    // Single file
    const item = data as { name: string; content?: string; encoding?: string; size?: number };
    if (isBinary(item.name)) {
      return NextResponse.json({ type: 'file', content: '(binary file)', encoding: 'utf8' });
    }

    // Gitea returns base64-encoded content
    const raw = item.content ?? '';
    let content: string;
    try {
      content = Buffer.from(raw.replace(/\n/g, ''), 'base64').toString('utf8');
    } catch {
      content = raw;
    }

    return NextResponse.json({ type: 'file', content, encoding: 'utf8', name: item.name });
  } catch (err) {
    console.error('[file API]', err);
    return NextResponse.json({ error: 'Failed to fetch file' }, { status: 500 });
  }
}