feat: polish

src/lib/api/predictions.ts

@@ -0,0 +1,34 @@
+import { api } from './client';
+import type { FlightParameters, RawPrediction } from '$domain';
+
+/**
+ * GFS datasets are published every 6 hours with a ~6 hour processing lag.
+ * Round down to the most recent available slot.
+ */
+export function getLatestDataset(now: Date = new Date()): string {
+	const rounded = new Date(now);
+	rounded.setUTCHours(Math.floor(rounded.getUTCHours() / 6) * 6, 0, 0, 0);
+	rounded.setUTCHours(rounded.getUTCHours() - 6);
+	return rounded.toISOString();
+}
+
+export function buildLaunchDateTime(date: string, time: string): string {
+	const fullTime = time.split(':').length === 2 ? `${time}:00` : time;
+	return new Date(`${date}T${fullTime}Z`).toISOString();
+}
+
+export interface PredictionResponse {
+	result: RawPrediction;
+}
+
+export const predictionsApi = {
+	run: (params: FlightParameters, launchDateTime: string) => {
+		const payload: FlightParameters & { launch_datetime: string } = {
+			...params,
+			dataset: params.dataset || getLatestDataset(),
+			launch_datetime: launchDateTime,
+		};
+		if (payload.start_point === -1) delete payload.start_point;
+		return api.post<PredictionResponse>('/predictions/', payload);
+	},
+};