3.2.2

Updated logo
Added average seasonal temps compare

assets/js/hooks/useForecast.js

@@ -39,6 +39,7 @@ const FIFTEEN_MIN_MS = 15 * 60 * 1000;
 const THIRTY_MIN_MS  = 30 * 60 * 1000;
 const SIX_HOURS_MS   =  6 * 60 * 60 * 1000;
 const ONE_MIN_MS     =  1 * 60 * 1000;
+const SIXTY_DAYS_MS  = 60 * 24 * 60 * 60 * 1000;
 
 function buildForecastUrl(loc) {
   return `https://api.open-meteo.com/v1/forecast` +
@@ -85,6 +86,85 @@ function soilCacheKey(loc) {
   return `sunscope_soil_${loc.lat.toFixed(4)}_${loc.lon.toFixed(4)}`;
 }
 
+// ─── CLIMATE NORMALS (ERA5 archive) ───────────────────────────────────────
+// Open-Meteo's Historical Archive gives daily mean temps back to 1940. We pull
+// the WMO reference period (1991-2020) once per location and reduce it into a
+// 366-entry day-of-year table of "normal" daily-mean temperature, so the app
+// can show how far the forecast for a day sits above/below its seasonal norm.
+// Normals don't change, so this caches for a long time.
+
+function buildClimateUrl(loc) {
+  return `https://archive-api.open-meteo.com/v1/archive` +
+    `?latitude=${loc.lat}&longitude=${loc.lon}` +
+    `&start_date=1991-01-01&end_date=2020-12-31` +
+    `&daily=temperature_2m_mean&timezone=auto`;
+}
+
+// Coarser key (~2 dp ≈ 1 km) so nearby lookups share one cached climatology.
+function climateCacheKey(loc) {
+  return `sunscope_normals_${loc.lat.toFixed(2)}_${loc.lon.toFixed(2)}`;
+}
+
+// Cumulative days before each month on a leap-year calendar, so every date
+// maps to a stable day-of-year slot (Mar 1 is always 60, Feb 29 is 59).
+const LEAP_CUM = [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335];
+function doyFromKey(key) {
+  const m = parseInt(key.slice(5, 7), 10);
+  const d = parseInt(key.slice(8, 10), 10);
+  return LEAP_CUM[m - 1] + (d - 1); // 0..365
+}
+
+// Reduce raw daily means into a smoothed 366-entry day-of-year normals table.
+function reduceNormals(daily) {
+  const times = daily?.time;
+  const means = daily?.temperature_2m_mean;
+  if (!times || !means) return null;
+  const sums = new Array(366).fill(0);
+  const counts = new Array(366).fill(0);
+  for (let i = 0; i < times.length; i++) {
+    const v = means[i];
+    if (v == null) continue;
+    const doy = doyFromKey(times[i]);
+    sums[doy] += v;
+    counts[doy] += 1;
+  }
+  const raw = sums.map((s, i) => (counts[i] > 0 ? s / counts[i] : null));
+  // ±7-day circular smoothing to remove single-day sampling noise.
+  const WIN = 7;
+  const smooth = new Array(366).fill(null);
+  for (let i = 0; i < 366; i++) {
+    let s = 0, n = 0;
+    for (let k = -WIN; k <= WIN; k++) {
+      const v = raw[(i + k + 366) % 366];
+      if (v != null) { s += v; n += 1; }
+    }
+    if (n > 0) smooth[i] = s / n;
+  }
+  return smooth;
+}
+
+// Fetches (or reads cached) climate normals for a location. Returns a
+// 366-entry array of daily-mean °C, or null on any failure (feature hides).
+async function fetchClimateNormals(loc) {
+  const key = climateCacheKey(loc);
+  try {
+    const cached = localStorage.getItem(key);
+    if (cached) {
+      const { ts, normals } = JSON.parse(cached);
+      if (normals && Date.now() - ts < SIXTY_DAYS_MS) return normals;
+    }
+  } catch (e) { /* ignore bad cache */ }
+  try {
+    const r = await fetch(buildClimateUrl(loc));
+    if (!r.ok) return null;
+    const json = await r.json();
+    const normals = reduceNormals(json.daily);
+    if (!normals) return null;
+    try { localStorage.setItem(key, JSON.stringify({ ts: Date.now(), normals })); } catch (e) {}
+    return normals;
+  } catch (e) { return null; } // network failure — feature just hides
+}
+
 // Fetches ICON soil hourly data with its own cache.
 // Returns stale cache of any age if the fetch fails — caller uses this as last resort.
 async function fetchSoilHourly(loc) {
@@ -130,6 +210,7 @@ export function useForecast(location, isPro = false) {
   const [error,     setError]     = useState(null);
   const [now,       setNow]       = useState(new Date());
   const [fetchedAt, setFetchedAt] = useState(null);
+  const [normals,   setNormals]   = useState(null);
 
   // Mirrors the latest forecast so the loader's catch block can tell whether
   // data is already on screen, even inside stale setInterval closures.
@@ -236,6 +317,12 @@ export function useForecast(location, isPro = false) {
   useEffect(() => {
     loadForecast(location);
     loadAirQuality(location);
+    // Climate normals are supplementary — load them without blocking. Clear
+    // first so a previous location's normals don't linger if this fetch fails.
+    setNormals(null);
+    if (location?.lat != null) {
+      fetchClimateNormals(location).then(n => { if (n) setNormals(n); });
+    }
   }, [location]);
 
   // ─── 1-MINUTE CLOCK TICK (current-row highlight + live scope) ─────
@@ -276,5 +363,5 @@ export function useForecast(location, isPro = false) {
     return () => clearInterval(id);
   }, [location, isPro]);
 
-  return { forecast, airQuality, loading, error, now, fetchedAt, liveElev };
+  return { forecast, airQuality, loading, error, now, fetchedAt, liveElev, normals };
 }