/*
	SPDX-FileCopyrightText: © 2025 Hornwitser <code@hornwitser.no>
	SPDX-License-Identifier: AGPL-3.0-or-later
*/
import { readSchedule, type ServerUser, writeSchedule } from '~/server/database';
import { broadcastEvent } from '~/server/streams';
import type { ApiSchedule, ApiTombstone } from '~/shared/types/api';

export async function updateScheduleInterestedCounts(users: ServerUser[]) {
	const eventCounts = new Map<number, number>();
	const eventSlotCounts = new Map<number, number>();
	for (const user of users) {
		if (user.deleted)
			continue;
		if (user.interestedEventIds)
			for (const id of user.interestedEventIds)
				eventCounts.set(id, (eventCounts.get(id) ?? 0) + 1);
		if (user.interestedEventSlotIds)
			for (const id of user.interestedEventSlotIds)
				eventSlotCounts.set(id, (eventSlotCounts.get(id) ?? 0) + 1);
	}

	const schedule = await readSchedule();
	if (schedule.deleted) {
		throw new Error("Deleted schedule not implemented");
	}
	const update: ApiSchedule = {
		id: schedule.id,
		updatedAt: new Date().toISOString(),
		events: [],
	};
	const updatedFrom = schedule.updatedAt;
	for (const event of schedule.events ?? []) {
		let modified = false;
		if (event.deleted)
			continue;

		let count = eventCounts.get(event.id);
		if (count !== event.interested) {
			event.interested = eventCounts.get(event.id);
			modified = true;
		}
		for (const slot of event.slots) {
			let slotCount = eventSlotCounts.get(slot.id);
			if (slotCount !== slot.interested) {
				slot.interested = slotCount;
				modified = true;
			}
		}
		if (modified) {
			event.updatedAt = update.updatedAt;
			update.events!.push(event);
		}
	}
	if (!update.events!.length) {
		return; // No changes
	}
	schedule.updatedAt = updatedFrom;
	await writeSchedule(schedule);
	await broadcastEvent({
		type: "schedule-update",
		updatedFrom,
		data: update,
	});
}

export function canSeeAnonymous(userType: string | undefined) {
	return userType === "admin";
}

export function canSeeCrew(userType: string | undefined) {
	return userType === "crew" || userType === "admin";
}

/** Filters out crew visible only parts of schedule */
export function filterSchedule(schedule: ApiSchedule | ApiTombstone): ApiSchedule | ApiTombstone {
	if (schedule.deleted) {
		return schedule;
	}
	return {
		id: schedule.id,
		updatedAt: schedule.updatedAt,
		locations: schedule.locations,
		events: (schedule.events ?? [])
			.map(event => (
				event.deleted
					? event
					: event.crew
						// Pretend crew events are deleted.
						? { id: event.id, deleted: true, updatedAt: event.updatedAt }
						: {
							...event,
							slots: event.slots.map(slot => ({
								...slot,
								assigned: undefined,
						}
				)),
			})),
	}
}