♻️ Moves analytics subscription handling to store

app/src/lib/stores/analytics.ts

@@ -1,19 +1,34 @@
 import { AnalyticsData } from '$lib/platform_shared/message'
 import { writable } from 'svelte/store'
-
-const analytics_data: AnalyticsData[] = []
+import { socket } from './socket'
 
 const maxAnalyticsData = 100
 
 function createAnalytics() {
-    const { subscribe, update } = writable(analytics_data)
+    const { subscribe, update } = writable<AnalyticsData[]>([])
+
+    let unsubscribe: (() => void) | null = null
+    let listenerCount = 0
+
+    const addData = (content: AnalyticsData) => {
+        update(data => [...data, content].slice(-maxAnalyticsData))
+    }
 
     return {
         subscribe,
-        addData: (content: AnalyticsData) => {
-            update(analytics_data => {
-                return [...analytics_data, content].slice(-maxAnalyticsData)
-            })
+        addData,
+        listen: () => {
+            listenerCount++
+            if (!unsubscribe) {
+                unsubscribe = socket.on(AnalyticsData, addData)
+            }
+        },
+        stop: () => {
+            listenerCount = Math.max(0, listenerCount - 1)
+            if (listenerCount === 0 && unsubscribe) {
+                unsubscribe()
+                unsubscribe = null
+            }
         }
     }
 }