fix: added energy-management

energy-management/backend/src/influx/power.ts

@@ -0,0 +1,51 @@
+import type { QueryApi } from "@influxdata/influxdb-client";
+import type { Env } from "../env.js";
+import type { PowerSample } from "../types.js";
+
+/**
+ * Fetches raw power samples between `sinceMs` and now.
+ * Converts the configured field to watts based on INFLUX_FIELD_UNIT.
+ */
+export async function fetchPowerSamplesSince(
+        queryApi: QueryApi,
+        env: Env,
+        sinceMs: number,
+): Promise<PowerSample[]> {
+        const sinceIso = new Date(sinceMs).toISOString();
+        const flux = `
+    from(bucket: "${env.INFLUX_BUCKET}")
+      |> range(start: ${sinceIso})
+      |> filter(fn: (r) => r["_measurement"] == "${env.INFLUX_FIELD_UNIT}")
+      |> filter(fn: (r) => r["_field"] == "${env.INFLUX_FIELD}")
+      |> filter(fn: (r) => r["domain"] == "${env.INFLUX_DOMAIN}")
+      |> filter(fn: (r) => r["entity_id"] == "${env.INFLUX_ENTITY_ID}")
+      |> sort(columns: ["_time"])
+  `;
+
+        const unitMultiplier = env.INFLUX_FIELD_UNIT === "kW" ? 1000 : 1;
+        const samples: PowerSample[] = [];
+
+        for await (const { values, tableMeta } of queryApi.iterateRows(flux)) {
+                const row = tableMeta.toObject(values) as { _time: string; _value: number };
+                samples.push({
+                        timestampMs: new Date(row._time).getTime(),
+                        watts: row._value * unitMultiplier,
+                });
+        }
+
+        return samples;
+}
+
+/** Fetches the single most recent power sample, if any exists within the lookback window. */
+export async function fetchLatestPowerSample(
+        queryApi: QueryApi,
+        env: Env,
+        lookbackMs = 60_000,
+): Promise<PowerSample | null> {
+        const samples = await fetchPowerSamplesSince(
+                queryApi,
+                env,
+                Date.now() - lookbackMs,
+        );
+        return samples.length > 0 ? samples[samples.length - 1] : null;
+}