import { NextRequest, NextResponse } from 'next/server';
import { auth } from '@/auth';
import { getEffectiveTier } from '@/lib/entitlements';
import { getAllowedByokProviders, isByokProviderAllowed } from '@/lib/byok';
import { fetchLiveModelsForProvider } from '@/lib/ai/models-list';
import { VALID_PROVIDERS, type AiGatewayProvider } from '@/lib/ai/router';

/**
 * GET /api/user/api-keys/live-models?provider=<provider>&key=<api_key>&baseUrl=<optional_custom_url>
 *
 * Dynamically queries the third-party provider's API with the user's key to fetch
 * actual available models dynamically.
 */
export async function GET(request: NextRequest) {
  const session = await auth();
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
  }

  const tier = await getEffectiveTier(session.user.id);
  if (tier === 'BASIC') {
    return NextResponse.json({ error: 'Forbidden' }, { status: 403 });
  }

  const { searchParams } = request.nextUrl;
  const provider = searchParams.get('provider') as AiGatewayProvider;
  const apiKey = searchParams.get('key');
  const baseUrl = searchParams.get('baseUrl') ?? undefined;

  if (!provider || !apiKey) {
    return NextResponse.json({ error: 'Missing parameters' }, { status: 400 });
  }

  if (!VALID_PROVIDERS.has(provider)) {
    return NextResponse.json({ error: 'Invalid provider' }, { status: 400 });
  }

  if (!isByokProviderAllowed(tier, provider)) {
    return NextResponse.json({ error: 'Tier restricted' }, { status: 403 });
  }

  const models = await fetchLiveModelsForProvider(provider, apiKey, baseUrl);

  return NextResponse.json({ success: true, models });
}