Re-add a new Latest Observations screen

server/scripts/modules/latestobservations.mjs

@@ -0,0 +1,183 @@
+// Latest Observations display - shows current conditions for 7 nearby cities
+import STATUS from './status.mjs';
+import { directionToNSEW } from './utils/calc.mjs';
+import WeatherDisplay from './weatherdisplay.mjs';
+import { registerDisplay } from './navigation.mjs';
+import {
+	temperature, windSpeed,
+} from './utils/units.mjs';
+import { getConditionText, getOpenMeteoObservationSnapshot } from './utils/weather.mjs';
+import { loadRadarCities } from './utils/leaflet-weather-map.mjs';
+
+class LatestObservations extends WeatherDisplay {
+	constructor(navId, elemId) {
+		super(navId, elemId, 'Latest Observations', true);
+		this.nearbyCities = [];
+		this.observations = [];
+	}
+
+	async getData(weatherParameters, refresh) {
+		const superResult = super.getData(weatherParameters, refresh);
+		this.data = await parseData(this.weatherParameters);
+		if (!this.data) {
+			this.setStatus(STATUS.failed);
+			return superResult;
+		}
+		this.setStatus(STATUS.loaded);
+		return superResult;
+	}
+
+	async drawCanvas() {
+		super.drawCanvas();
+		if (!this.data || this.data.length === 0) {
+			this.finishDraw();
+			return;
+		}
+
+		// Templates are extracted by WeatherDisplay.loadTemplates(), so rebuild rows from stored templates only.
+		const container = this.elem.querySelector('.observation-lines');
+		container.innerHTML = '';
+
+		// Add observation rows
+		this.data.forEach((obs) => {
+			const row = this.fillTemplate('observation-row', {
+				city: obs.city,
+				temp: obs.temp,
+				conditions: obs.conditions,
+				wind: obs.wind,
+			});
+			if (row) container.appendChild(row);
+		});
+
+		this.finishDraw();
+	}
+}
+
+// Truncate city name to 15 characters
+const truncateCityName = (name) => {
+	if (!name) return '';
+	if (name.length <= 15) return name;
+	return name.substring(0, 15);
+};
+
+// Shorten weather conditions (similar to currentweather.mjs)
+const shortConditions = (condition) => {
+	if (!condition) return '';
+
+	// Apply abbreviations
+	let result = condition;
+	result = result.replace(/Light/g, 'Lt');
+	result = result.replace(/Heavy/g, 'Hvy');
+	result = result.replace(/Moderate/g, 'Mod');
+	result = result.replace(/Partly/g, 'Pt');
+	result = result.replace(/Mostly/g, 'Mt');
+	result = result.replace(/Thunderstorm/g, 'T-storm');
+	result = result.replace(/Freezing Rain/g, 'Frz Rn');
+	result = result.replace(/Freezing/g, 'Frz');
+	result = result.replace(/Drizzle/g, 'Drzl');
+	result = result.replace(/Showers/g, 'Shwrs');
+	result = result.replace(/Slight/g, 'Slt');
+
+	// Truncate to 8 characters if still too long
+	if (result.length > 8) {
+		result = result.substring(0, 8);
+	}
+
+	return result;
+};
+
+// Calculate distance between two lat/lng points in meters (Haversine formula)
+const calculateDistance = (lat1, lon1, lat2, lon2) => {
+	const R = 6371e3; // Earth's radius in meters
+	const φ1 = (lat1 * Math.PI) / 180;
+	const φ2 = (lat2 * Math.PI) / 180;
+	const Δφ = ((lat2 - lat1) * Math.PI) / 180;
+	const Δλ = ((lon2 - lon1) * Math.PI) / 180;
+
+	const a = Math.sin(Δφ / 2) * Math.sin(Δφ / 2)
+		+ Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) * Math.sin(Δλ / 2);
+	const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+
+	return R * c;
+};
+
+// Select nearby cities by distance (simpler version without map dependency)
+const selectNearbyCitiesSimple = (sourceLocation, cities, maxCities = 7, minDistanceMeters = 15000) => {
+	const citiesWithDistance = cities
+		.map((city) => ({
+			...city,
+			distance: calculateDistance(
+				sourceLocation.latitude,
+				sourceLocation.longitude,
+				city.lat,
+				city.lon
+			),
+		}))
+		.filter((city) => city.distance > minDistanceMeters)
+		.sort((a, b) => a.distance - b.distance);
+
+	return citiesWithDistance.slice(0, maxCities);
+};
+
+const parseData = async (weatherParameters) => {
+	if (!weatherParameters?.latitude || !weatherParameters?.longitude) {
+		return null;
+	}
+
+	// Load radar cities and select 7 nearby
+	const radarCities = await loadRadarCities();
+	if (!radarCities || radarCities.length === 0) {
+		return null;
+	}
+
+	const nearbyCities = selectNearbyCitiesSimple({
+		latitude: weatherParameters.latitude,
+		longitude: weatherParameters.longitude,
+	}, radarCities, 7, 15000);
+
+	if (!nearbyCities || nearbyCities.length === 0) {
+		return null;
+	}
+
+	// Fetch observations for each city
+	const temperatureConverter = temperature();
+	const windConverter = windSpeed();
+
+	const observations = await Promise.all(
+		nearbyCities.map(async (city) => {
+			try {
+				const observation = await getOpenMeteoObservationSnapshot(city.lat, city.lon);
+				if (!observation || observation.temperature === null) {
+					return null;
+				}
+
+				// Format condition text
+				const conditionText = getConditionText(observation.weatherCode);
+				const shortCondition = shortConditions(conditionText);
+
+				// Format wind
+				const windDir = directionToNSEW(observation.windDirection || 0);
+				const windSpd = Math.round(windConverter(observation.windSpeed));
+				const windText = windSpd > 0 ? `${windDir} ${windSpd}` : 'Calm';
+
+				return {
+					city: truncateCityName(city.name),
+					temp: temperatureConverter(observation.temperature),
+					conditions: shortCondition,
+					wind: windText,
+				};
+			} catch (e) {
+				console.warn(`Failed to get observation for ${city.name}:`, e);
+				return null;
+			}
+		})
+	);
+
+	// Filter out failed observations and limit to 7
+	return observations.filter((obs) => obs !== null).slice(0, 7);
+};
+
+const display = new LatestObservations(2, 'latest-observations');
+registerDisplay(display);
+
+export default display;