Move more core logic to new folder

src/lib/storage/AppStorage.ts

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+// eslint-disable-next-line max-classes-per-file
+export class Storage {
+    constructor(private readonly storage: typeof window.localStorage) {}
+
+    parseValue<T>(value: string | null, defaultValue: T): T {
+        if (value === null) {
+            return defaultValue;
+        }
+
+        return JSON.parse(value);
+    }
+
+    getItem(key: string): string | null {
+        return this.storage.getItem(key);
+    }
+
+    getItemParsed<T>(key: string, defaultValue: T): T {
+        return this.parseValue(this.getItem(key), defaultValue);
+    }
+
+    setItem(key: string, value: unknown, emitEvent: boolean = true): void {
+        const fireEvent = (valueToStore: string | undefined) => {
+            if (!emitEvent) {
+                return;
+            }
+
+            window.dispatchEvent(
+                new StorageEvent('storage', {
+                    key,
+                    oldValue: this.getItem(key),
+                    newValue: valueToStore,
+                }),
+            );
+        };
+
+        if (value === undefined) {
+            this.storage.removeItem(key);
+            fireEvent(undefined);
+            return;
+        }
+
+        const valueToStore = JSON.stringify(value);
+
+        this.storage.setItem(key, valueToStore);
+        fireEvent(valueToStore);
+    }
+}
+
+export class AppStorage {
+    static readonly local: Storage = new Storage(window.localStorage);
+
+    static readonly session: Storage = new Storage(window.sessionStorage);
+}