add update_all_display_status interval, improve code structure

control/frontend/src/ts/main.ts

@@ -1,4 +1,22 @@
-export function on_start() {
+import { get } from "svelte/store";
+import { displays, update_displays_with_map } from "./stores/displays"
+import { ping_ip } from "./api_handler";
+import type { Display } from "./types";
+import { change_file_path } from "./stores/files";
 
+const update_display_status_interval_seconds = 20;
+
+export function on_start() {
+    update_all_display_status();
+    setInterval(update_all_display_status, update_display_status_interval_seconds * 1000);
 }
 
+
+async function update_all_display_status() {
+    update_displays_with_map(async (display: Display) => {
+        const new_status = await ping_ip(display.ip);
+        if (new_status === null && display.status !== null) return display;
+        return { ...display, status: new_status, };
+    });
+    console.log("Display Status updated")
+}