apple2js/js/prefs.ts

44 lines
1.1 KiB
TypeScript
Raw Normal View History

const havePrefs = typeof window.localStorage !== 'undefined';
export default class Prefs {
url: URL;
title: string;
constructor() {
this.url = new URL(window.location.href);
this.title = window.document.title;
}
havePrefs() {
return havePrefs;
}
readPref(name: string): string | null;
readPref(name: string, defaultValue: string): string;
readPref(name: string, defaultValue: string | null = null) {
if (this.url.searchParams.has(name)) {
return this.url.searchParams.get(name);
}
if (havePrefs) {
return window.localStorage.getItem(name) ?? defaultValue;
}
return defaultValue;
}
writePref(name: string, value: string) {
if (this.url.searchParams.has(name)) {
this.url.searchParams.set(name, value);
history.replaceState(
null,
this.title,
this.url.toString()
);
}
if (havePrefs) {
window.localStorage.setItem(name, value);
}
}
}