/*
	SPDX-FileCopyrightText: © 2025 Hornwitser <code@hornwitser.no>
	SPDX-License-Identifier: AGPL-3.0-or-later
*/
import { Info } from "~/shared/utils/luxon";

interface SyncOperation {
	controller: AbortController,
	promise: Promise<Ref<ClientSchedule>>,
}

export const useSchedulesStore = defineStore("schedules", () => {
	const sessionStore = useSessionStore();
	const accountStore = useAccountStore();

	const state = {
		activeScheduleId: ref<number | undefined>(111),
		schedules: ref<Map<number, Ref<ClientSchedule>>>(new Map()),
		pendingSyncs: ref<Map<number, SyncOperation>>(new Map()),
	};

	const getters = {
		activeSchedule: computed(() => {
			if (state.activeScheduleId.value === undefined)
				throw Error("No active schedule");
			const schedule = state.schedules.value.get(state.activeScheduleId.value);
			if (!schedule)
				throw Error("Active schedule has not been fetched");
			return schedule;
		}),
	};

	const actions = {
		async fetch(id: number) {
			if (id !== 111) { throw Error("invalid id"); }
			console.log("schedules store fetch", id);
			const schedule = state.schedules.value.get(id);
			if (schedule) {
				console.log("return cached");
				return schedule;
			}
			const pending = state.pendingSyncs.value.get(id);
			if (pending) {
				console.log("return pending");
				return pending.promise;
			}

			console.log("return new fetch");
			const requestFetch = useRequestFetch();
			const controller = new AbortController();
			const zone = Info.normalizeZone(accountStore.activeTimezone);
			const locale = accountStore.activeLocale;
			const promise = (async () => {
				try {
					const apiSchedule = await requestFetch("/api/schedule", { signal: controller.signal });
					if (apiSchedule.deleted) {
						throw new Error("Unexpecetd deleted schedule");
					}
					const schedule = ref(ClientSchedule.fromApi(apiSchedule, { zone, locale })) as Ref<ClientSchedule>;
					state.schedules.value.set(id, schedule);
					state.pendingSyncs.value.delete(id);
					return schedule;
				} catch (err: any) {
					if (err.name !== "AbortError")
						state.pendingSyncs.value.delete(id);
					throw err;
				}
			})();
			state.pendingSyncs.value.set(id, {
				controller,
				promise,
			});
			return promise;
		},
		async resync(id: number) {
			if (id !== 111) { throw Error("invalid id"); }
			const pending = state.pendingSyncs.value.get(id);
			if (pending) {
				pending.controller.abort();
			}
			state.schedules.value.delete(id);
			state.pendingSyncs.value.delete(id);
			await actions.fetch(id);
		},
	}

	watch(() => sessionStore.id, (id, oldId) => {
		for (const [scheduleId, pending] of state.pendingSyncs.value) {
			console.log("Aborting pending schedule sync", scheduleId, "due session.id change from", oldId, "to", id);
			pending.controller.abort();
			state.pendingSyncs.value.delete(scheduleId);
		}
	})

	appEventSource?.addEventListener("update", (event) => {
		if (event.data.type !== "schedule-update") {
			return;
		}
		const schedule = state.schedules.value.get(111);
		const update = event.data.data;
		// XXX validate updatedFrom/updatedAt here
		if (schedule && !schedule.value.deleted && !update.deleted) {
			const zone = Info.normalizeZone(accountStore.activeTimezone);
			const locale = accountStore.activeLocale;
			schedule.value.apiUpdate(update, { zone, locale })
		}
	});

	return { ...state, ...getters, ...actions };
});