/**
 * GET /api/public/feedback/<slug>             — public-facing instance config (slug = access token).
 * GET /api/public/feedback/<slug>?session_id= — also resolves the caller's previous submission
 *                                               when single_submission is on, so the participant
 *                                               page can render the read-only summary on first
 *                                               paint instead of falling through to the legacy
 *                                               "submit again" branch on reload.
 */
import type { RequestHandler } from './$types';
import { json } from '$lib/server/response';
import { handleApiError, notFound } from '$lib/server/errors';
import { getInstanceBySlug, clampUserAgent } from '$lib/server/feedback';
import { fdb } from '$lib/server/fdb';

export const GET: RequestHandler = async ({ params, url, request, getClientAddress }) => {
	try {
		const inst = await getInstanceBySlug(params.slug);
		if (!inst) return notFound('Feedback instance not found');

		let previousSubmission:
			| { submitted_at: string; display_name: string | null; answers: unknown }
			| null = null;

		if (inst.single_submission) {
			const cols = 'answers, display_name, created_at';
			const sessionId = url.searchParams.get('session_id');

			if (sessionId && sessionId.length > 0 && sessionId.length <= 100) {
				const r = await fdb()
					.from('feedback_submissions')
					.select(cols)
					.eq('instance_id', inst.id)
					.eq('client_session_id', sessionId)
					.order('created_at', { ascending: false })
					.limit(1)
					.maybeSingle();
				if (r.error) throw r.error;
				if (r.data) {
					previousSubmission = {
						submitted_at: r.data.created_at,
						display_name: r.data.display_name,
						answers: r.data.answers,
					};
				}
			}

			// Back-stop: same IP + UA. Catches the "cleared LocalStorage but same browser" case.
			if (!previousSubmission) {
				const ip = getClientAddress();
				const ua = clampUserAgent(request.headers.get('user-agent'));
				if (ua) {
					const r = await fdb()
						.from('feedback_submissions')
						.select(cols)
						.eq('instance_id', inst.id)
						.eq('client_ip', ip)
						.eq('user_agent', ua)
						.order('created_at', { ascending: false })
						.limit(1)
						.maybeSingle();
					if (r.error) throw r.error;
					if (r.data) {
						previousSubmission = {
							submitted_at: r.data.created_at,
							display_name: r.data.display_name,
							answers: r.data.answers,
						};
					}
				}
			}
		}

		return json({
			title: inst.title,
			description: inst.description,
			form_definition: inst.form_definition,
			chat_enabled: inst.chat_enabled,
			live_results_enabled: inst.live_results_enabled,
			single_submission: inst.single_submission,
			status: inst.status,
			closed_at: inst.closed_at,
			previous_submission: previousSubmission,
		});
	} catch (e) {
		return handleApiError(e, 'feedback GET');
	}
};