Add settings store

src/lib/settings/index.ts

@@ -0,0 +1,45 @@
+import { browser } from "$app/environment";
+import { writable } from "svelte/store";
+
+type Settings = {
+  zoomMode: 'keep' | 'something'
+  rightToLeft: boolean;
+  singlePageView: boolean;
+  textEditable: boolean;
+  textBoxBorders: boolean;
+  displayOCR: boolean;
+};
+
+const defaultSettings: Settings = {
+  zoomMode: 'keep',
+  rightToLeft: true,
+  singlePageView: false,
+  displayOCR: true,
+  textEditable: false,
+  textBoxBorders: false
+}
+
+const stored = browser ? window.localStorage.getItem('settings') : undefined
+const initialSettings: Settings = stored && browser ? JSON.parse(stored) : defaultSettings
+
+export const settingsStore = writable<Settings>(initialSettings);
+
+export function updateSetting(key: string, value: any) {
+  settingsStore.update((settings) => {
+    return {
+      ...settings,
+      [key]: value
+    };
+  });
+}
+
+export function resetSettings() {
+  settingsStore.set(defaultSettings);
+}
+
+settingsStore.subscribe((settings) => {
+  if (browser) {
+    window.localStorage.setItem('settings', JSON.stringify(settings))
+  }
+})
+