import { json, error } from '@sveltejs/kit';
import type { RequestHandler } from './$types';
import { presignAudio } from '$lib/server/minio';
import { log } from '$lib/server/logger';

/**
 * GET /api/presign/audio?slug=...&n=...&voice=...
 * Returns a presigned MinIO URL for the audio file so the browser
 * can stream it directly without going through the server.
 * Returns 404 when the audio has not been generated yet.
 */
export const GET: RequestHandler = async ({ url }) => {
	const slug = url.searchParams.get('slug');
	// Accept both 'n' (web) and 'chapter' (iOS) as the chapter number param
	const n = parseInt(url.searchParams.get('n') ?? url.searchParams.get('chapter') ?? '', 10);
	const voice = url.searchParams.get('voice') ?? undefined;

	if (!slug || !n || n < 1) {
		error(400, 'Missing slug or n');
	}

	try {
		const presignedUrl = await presignAudio(slug, n, voice);
		return json({ url: presignedUrl });
	} catch (e) {
		const status = (e as { status?: number }).status;
		if (status === 404) {
			error(404, 'Audio not found');
		}
		log.error('presign', 'presign audio failed', { slug, n, err: String(e) });
		error(500, `Could not get presigned URL: ${e}`);
	}
};