decompose structure

src/features/electrical-schematics/useElectricalLiveValues.ts

@@ -0,0 +1,83 @@
+import { useEffect, useState } from 'react';
+import { getCurrent, getCurrentEventsUrl } from '../../entities/current/api';
+import type { CurrentEvent, CurrentResponse } from '../../entities/current/types';
+import type { LiveGroup, LiveValue } from './types';
+
+function buildCustomSseUrl(sseUrl: string, tags: string[]): string {
+  const url = new URL(sseUrl, window.location.origin);
+  if (tags.length && !url.searchParams.has('tags')) {
+    tags.forEach((tag) => url.searchParams.append('tags', tag));
+  }
+
+  return url.toString();
+}
+
+export function useElectricalLiveValues(liveGroups: LiveGroup[], resetKey?: string) {
+  const [liveValues, setLiveValues] = useState(() => new Map<string, LiveValue>());
+  const [connectedSources, setConnectedSources] = useState<Set<string>>(new Set());
+
+  useEffect(() => {
+    setLiveValues(new Map());
+    setConnectedSources(new Set());
+  }, [resetKey]);
+
+  useEffect(() => {
+    if (!liveGroups.length) {
+      return undefined;
+    }
+
+    let closed = false;
+    const eventSources: EventSource[] = [];
+
+    const mergeResponse = (response: CurrentResponse, sourceKey: string) => {
+      if (closed) {
+        return;
+      }
+
+      setLiveValues((previous) => {
+        const next = new Map(previous);
+        response.items.forEach((item) => {
+          const value = { ...item, sourceKey };
+          next.set(`${item.edge}:${item.tag}`, value);
+          next.set(`tag:${item.tag}`, value);
+        });
+        return next;
+      });
+    };
+
+    liveGroups.forEach((group) => {
+      if (!group.sseUrl) {
+        void getCurrent(group.edgeId, group.tags).then((response) => mergeResponse(response, group.sourceKey));
+      }
+
+      const url = group.sseUrl ? buildCustomSseUrl(group.sseUrl, group.tags) : getCurrentEventsUrl(group.edgeId, group.tags);
+      const eventSource = new EventSource(url);
+
+      eventSource.onopen = () => {
+        setConnectedSources((previous) => new Set(previous).add(group.sourceKey));
+      };
+
+      eventSource.onerror = () => {
+        setConnectedSources((previous) => {
+          const next = new Set(previous);
+          next.delete(group.sourceKey);
+          return next;
+        });
+      };
+
+      eventSource.onmessage = (message) => {
+        const event = JSON.parse(message.data) as CurrentEvent;
+        mergeResponse(event, group.sourceKey);
+      };
+
+      eventSources.push(eventSource);
+    });
+
+    return () => {
+      closed = true;
+      eventSources.forEach((eventSource) => eventSource.close());
+    };
+  }, [liveGroups]);
+
+  return { connectedSources, liveValues };
+}