import express from 'express';
import {resolve, dirname} from 'path';
import {fileURLToPath} from 'url';
import {cfg} from './config.mjs';
import {queryCurrent, queryHourly, queryDaily, getCoords} from './influx.mjs';
import {getCelestialCurrent, getCelestialHourly, getCelestialDaily, getCelestialForecast} from './celestial.mjs';
import {getSpaceWeather} from './space.mjs';
import {getOpenMeteo} from './openmeteo.mjs';
import {apiReference} from '@scalar/express-api-reference';
import {spec} from './spec.mjs';
import {existsSync} from 'fs';
import {getAirTraffic, getAirTrafficHistory, getShapes} from './airtraffic.mjs';

const app = express();
const DIR = dirname(fileURLToPath(import.meta.url));
const CLIENT_DIST = resolve(DIR, 'public');

app.use(express.json());
app.use('/icons', express.static(resolve(DIR, 'public', 'icons')));
app.use((req, res, next) => {
	res.setHeader('Access-Control-Allow-Origin', '*');
	next();
});
app.use(express.static(CLIENT_DIST));

function filterFields(obj, fields) {
	if(!fields) return obj;
	const keys = new Set(fields.split(',').map(f => f.trim()));
	return Object.fromEntries(Object.entries(obj).filter(([k]) => keys.has(k)));
}

function filterArr(arr, fields) {
	if(!fields) return arr;
	return arr.map(row => filterFields(row, fields));
}

// ── Sensor Data ───────────────────────────────────────────────────────────────

app.get('/api/current', async (req, res) => {
	const {fields} = req.query;
	const [sensors, space] = await Promise.all([queryCurrent(), getCelestialCurrent()]);
	res.json(filterFields({...sensors, ...space}, fields));
});

// ── Position ──────────────────────────────────────────────────────────────────

app.get('/api/position', async (req, res) => {
	const {fields} = req.query;
	const data = await getCoords();
	res.json(filterFields(data, fields));
});

// ── Space ─────────────────────────────────────────────────────────────────────

app.get('/api/space', async (req, res) => {
	const {fields} = req.query;
	res.json(filterFields(await getSpaceWeather(), fields));
});

// ── Daily History/Forecast ────────────────────────────────────────────────────

app.get('/api/hourly', async (req, res) => {
	const {fields} = req.query;
	const start = req.query.start || new Date(new Date().setHours(0, 0, 0, 0)).toISOString();
	let now = new Date();
	now.setHours(new Date().getHours() - 1, 0, 0);
	now = now.toISOString();
	const end = req.query.end || new Date().toISOString();
	const coords = await getCoords();
	const [sensor, meteo] = await Promise.allSettled([
		queryHourly(start, now),
		getOpenMeteo(coords.latitude, coords.longitude, now, end),
	]);
	const history = sensor.status === 'fulfilled' ? sensor.value : [];
	const forecast = meteo.status === 'fulfilled' ? meteo.value.hourly : [];
	const hourly = getCelestialForecast(coords.latitude, coords.longitude, [...history, ...forecast]);
	res.json(filterArr(hourly, fields));
});

// ── Hourly History/Forecast ───────────────────────────────────────────────────

app.get('/api/daily', async (req, res) => {
	const {fields} = req.query;
	const start = req.query.start || new Date(new Date().setHours(0, 0, 0, 0)).toISOString();
	let now = new Date();
	now.setDate(now.getDate() - 1);
	now.setHours(0, 0, 0, 0);
	now = now.toISOString();
	const end = req.query.end || new Date().toISOString();
	const coords = await getCoords();
	const [sensor, meteo] = await Promise.allSettled([
		queryDaily(start, now),
		getOpenMeteo(coords.latitude, coords.longitude, now, end),
	]);
	const history = sensor.status === 'fulfilled' ? sensor.value : [];
	const forecast = meteo.status === 'fulfilled' ? meteo.value.daily : [];
	const daily = getCelestialForecast(coords.latitude, coords.longitude, [...history, ...forecast]);
	res.json(filterArr(daily, fields));
});

// ── ADSB Proxy ────────────────────────────────────────────────────────────────

app.get('/api/air-traffic', async (req, res) => res.json(await getAirTraffic()));
app.get('/api/air-traffic/:icao', async (req, res) => res.json(await getAirTrafficHistory(req.params.icao)));
app.get('/api/air-traffic-shapes', async (req, res) => res.json(await getShapes()));

// ── DOCS ──────────────────────────────────────────────────────────────────────

app.use('/docs', apiReference({spec: {url: '/openapi.json'}, theme: 'default'}));
app.get('/openapi.json', (req, res) => res.json(spec));
app.get('/openapi.yaml', async (req, res) => {
	const {stringify} = await import('yaml');
	res.setHeader('Content-Type', 'text/yaml');
	res.send(stringify(spec));
});

// ── Website ───────────────────────────────────────────────────────────────────

app.get('*', (req, res) => {
	const index = resolve(CLIENT_DIST, 'index.html');
	if(existsSync(index)) res.sendFile(index);
	else res.status(404).send('Client not built yet — run npm run build in /client');
});

// ── Start ─────────────────────────────────────────────────────────────────────

const c = cfg();
app.listen(c.PORT, () => console.log(`🌦  Weather API — http://localhost:${c.PORT}`));