import { redirect } from '@sveltejs/kit';
import type { PageServerLoad } from './$types';
import {
	listUserSessions,
	getUserByUsername,
	getUserStats,
	allProgress,
	getBooksBySlugs
} from '$lib/server/pocketbase';
import { resolveAvatarUrl } from '$lib/server/minio';
import { log } from '$lib/server/logger';

export const load: PageServerLoad = async ({ locals }) => {
	if (!locals.user) {
		redirect(302, '/login');
	}

	// Helper: fetch reading history (progress → books, sequential by necessity)
	async function fetchHistory() {
		const progress = await allProgress(locals.sessionId, locals.user!.id);
		const recent = progress.slice(0, 50);
		const books = await getBooksBySlugs(new Set(recent.map((p) => p.slug)));
		const bookMap = new Map(books.map((b) => [b.slug, b]));
		return recent.map((p) => ({
			slug: p.slug,
			chapter: p.chapter,
			updated: p.updated,
			title: bookMap.get(p.slug)?.title ?? p.slug,
			cover: bookMap.get(p.slug)?.cover ?? null
		}));
	}

	// Helper: fetch avatar/email/polarCustomerId (getUserByUsername → resolveAvatarUrl)
	async function fetchUserRecord() {
		const record = await getUserByUsername(locals.user!.username);
		const avatarUrl = await resolveAvatarUrl(locals.user!.id, record?.avatar_url);
		return {
			avatarUrl,
			email: record?.email ?? null,
			polarCustomerId: record?.polar_customer_id ?? null
		};
	}

	// Run all three independent groups concurrently
	const [userRecord, sessionsResult, statsResult, historyResult] = await Promise.allSettled([
		fetchUserRecord(),
		listUserSessions(locals.user.id),
		getUserStats(locals.sessionId, locals.user.id),
		fetchHistory()
	]);

	if (userRecord.status === 'rejected')
		log.warn('profile', 'avatar fetch failed (non-fatal)', { err: String(userRecord.reason) });
	if (sessionsResult.status === 'rejected')
		log.warn('profile', 'sessions fetch failed (non-fatal)', { err: String(sessionsResult.reason) });
	if (statsResult.status === 'rejected')
		log.warn('profile', 'stats fetch failed (non-fatal)', { err: String(statsResult.reason) });
	if (historyResult.status === 'rejected')
		log.warn('profile', 'history fetch failed (non-fatal)', { err: String(historyResult.reason) });

	const { avatarUrl = null, email = null, polarCustomerId = null } =
		userRecord.status === 'fulfilled' ? userRecord.value : {};
	const sessions =
		sessionsResult.status === 'fulfilled' ? sessionsResult.value : [];
	const stats =
		statsResult.status === 'fulfilled' ? statsResult.value : null;
	const history =
		historyResult.status === 'fulfilled' ? historyResult.value : [];

	return {
		user: locals.user,
		avatarUrl,
		email,
		polarCustomerId,
		stats: stats ?? {
			totalChaptersRead: 0, booksReading: 0, booksCompleted: 0,
			booksPlanToRead: 0, booksDropped: 0, topGenres: [],
			avgRatingGiven: 0, streak: 0
		},
		sessions: sessions.map((s) => ({
			id: s.id,
			user_agent: s.user_agent,
			ip: s.ip,
			created_at: s.created_at,
			last_seen: s.last_seen,
			is_current: s.session_id === locals.user!.authSessionId
		})),
		history
	};
};