chore(control): improve startup behavoir

closes #22

control/frontend/src/lib/ts/main.ts

@@ -1,8 +1,8 @@
 import { screenshot_loop } from './stores/displays';
 import { ping_ip } from './api_handler';
 import type { Display, DisplayStatus } from './types';
-import { update_folder_elements_recursively } from './stores/files';
 import { db } from './database';
+import { update_changed_directories } from './stores/files';
 
 const update_display_status_interval_seconds = 20;
 const update_display_loading_status_interval_seconds = 2;
@@ -10,8 +10,6 @@ const update_display_loading_status_interval_seconds = 2;
 const loading_display_ids: string[] = [];
 
 export async function on_app_start() {
-	await db.files.clear();
-	await db.files_on_display.clear();
 	await db.displays
 		.toCollection()
 		.modify({ status: null, preview: { currently_updating: false, url: null } });
@@ -47,17 +45,19 @@ export async function update_display_status(display: Display): Promise<DisplaySt
 	}
 	if (resp.status === null && display.status !== null) return null;
 	if (resp.status !== display.status) {
+		let run_on_display_start = false;
 		// status change
 		if (resp.status === 'app_offline') {
 			loading_display_ids.push(display.id);
 		} else {
 			remove_display_from_loading_displays(display.id);
 			if (resp.status === 'app_online') {
-				on_display_start(display);
+				run_on_display_start = true;
 			}
 		}
 		display.status = resp.status;
 		await db.displays.put(display); // save
+		if (run_on_display_start) await on_display_start(display);
 	}
 	return resp.status;
 }
@@ -70,6 +70,6 @@ export function remove_display_from_loading_displays(display_id: string) {
 }
 
 async function on_display_start(display: Display) {
-	await update_folder_elements_recursively(display, '/');
+	await update_changed_directories(display);
 	screenshot_loop(display.id);
 }

control/frontend/src/lib/ts/stores/files.ts

@@ -33,7 +33,7 @@ export async function change_file_path(new_path: string) {
 	}
 }
 
-async function update_changed_directories(display: Display, path: string = '/') {
+export async function update_changed_directories(display: Display, path: string = '/') {
 	const changed_paths = await get_changed_directory_paths(display, path);
 	if (!changed_paths) return;
 	console.debug('Update file system from', display.name, ':', changed_paths);
@@ -239,7 +239,7 @@ async function get_recursive_changed_directory_paths(
 	return has_changed;
 }
 
-export async function update_folder_elements_recursively(
+async function update_folder_elements_recursively(
 	display: Display,
 	file_path: string = '/'
 ): Promise<void> {