import {ref, onUnmounted} from 'vue';

export type DataRow = Record<string, number | string | null>

export const BASE = import.meta.env.DEV ? 'http://10.69.5.23' : '';

const cache: any = {};
const current = ref<any>(null);
const hourly = ref<any[]>([]);
const daily = ref<any[]>([]);

let interval: ReturnType<typeof setInterval>;
let refCount = 0;

async function get<T>(path: string, params: Record<string, string> = {}): Promise<T> {
	const url = new URL(`${BASE}${path}`, window.location.origin);
	Object.entries(params).forEach(([k, v]) => url.searchParams.set(k, v));
	const key = url.toString();
	if(cache[key]) return cache[key];
	cache[key] = fetch(url.toString())
		.then(resp => resp.json())
		.finally(() => delete cache[key]);
	return cache[key];
}

export const api = {
	position: (fields?: string) => get<{latitude: number, longitude: number, altitude: number}>('/api/position', fields ? {fields} : {}),
	current: (fields?: string) => get<DataRow>('/api/current', fields ? {fields} : {}),
	hourly: (start?: Date | string, end?: Date | string, fields?: string) => get<DataRow[]>('/api/hourly', {
		...(start ? {start: typeof start == 'string' ? start : start.toISOString()} : {}),
		...(end ? {end: typeof end == 'string' ? end : end.toISOString()} : {}),
		...(fields ? {fields} : {})
	}),
	daily: (start?: Date, end?: Date, fields?: string) => get<DataRow[]>('/api/daily', {
		...(start ? {start: typeof start == 'string' ? start : start.toISOString()} : {}),
		...(end ? {end: typeof end == 'string' ? end : end.toISOString()} : {}),
		...(fields ? {fields} : {})
	}),
};

async function refresh() {
	const start = new Date(), end = new Date();
	start.setDate(start.getDate() + 1);
	end.setDate(end.getDate() + 5);
	current.value = await api.current();
	return {current}
}

export function useWeather(ms = 5 * 60_000) {
	if(++refCount === 1) {
		refresh();
		interval = setInterval(refresh, ms);
	}

	onUnmounted(() => {
		if(--refCount === 0) clearInterval(interval);
	});

	return {current, hourly, daily, refresh};
}
