import { type NextRequest, NextResponse } from 'next/server';
import { requireAdminApi } from '@/lib/auth/admin-guard';
import { getAuditList } from '@/lib/admin/list';
import { logAdminAction } from '@/lib/auth/audit';
import { toCsv, EXPORT_MAX_ROWS } from '@/lib/admin/csv';

export const runtime = 'nodejs';
export const dynamic = 'force-dynamic';

export async function GET(req: NextRequest) {
  const auth = await requireAdminApi();
  if (!auth.ok) return auth.response;

  const url = new URL(req.url);
  const action = url.searchParams.get('action') ?? '';
  const targetType = url.searchParams.get('target_type') ?? '';
  const sort = url.searchParams.get('sort');
  const order = url.searchParams.get('order');

  try {
    // Respect action/target_type filters + sort, full set (capped). Audit
    // details already exclude secrets (no tokens are ever logged).
    const { entries } = await getAuditList({
      page: 1,
      perPage: EXPORT_MAX_ROWS,
      action,
      targetType,
      sort,
      order,
    });

    const header = [
      'created_at',
      'actor_email',
      'action',
      'target_type',
      'target_id',
      'details',
    ];
    const rows = entries.map((e) => [
      e.created_at,
      e.actor_email ?? '',
      e.action,
      e.target_type ?? '',
      e.target_id ?? '',
      JSON.stringify(e.details ?? {}),
    ]);

    const csv = toCsv(header, rows);

    await logAdminAction(auth.user, {
      action: 'audit.export',
      target_type: 'audit',
      details: { count: rows.length, capped: rows.length >= EXPORT_MAX_ROWS },
    });

    return new NextResponse(csv, {
      status: 200,
      headers: {
        'Content-Type': 'text/csv; charset=utf-8',
        'Content-Disposition': 'attachment; filename="audit.csv"',
        'Cache-Control': 'no-store',
        Pragma: 'no-cache',
      },
    });
  } catch (e) {
    console.error('admin audit export failed', e);
    return NextResponse.json(
      { error: 'internal error' },
      { status: 500, headers: { 'Cache-Control': 'no-store' } },
    );
  }
}