1 files changed, 94 insertions, 0 deletions
diff --git a/ext/js/pages/settings/persistent-storage-controller.js b/ext/js/pages/settings/persistent-storage-controller.js
new file mode 100644
index 00000000..e46dbe87
--- /dev/null
+++ b/ext/js/pages/settings/persistent-storage-controller.js
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2021  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+class PersistentStorageController {
+    constructor() {
+        this._persistentStorageCheckbox = false;
+    }
+
+    async prepare() {
+        this._persistentStorageCheckbox = document.querySelector('#storage-persistent-checkbox');
+        this._persistentStorageCheckbox.addEventListener('change', this._onPersistentStorageCheckboxChange.bind(this), false);
+
+        const button = document.querySelector('#storage-persistent-button');
+        if (button !== null) {
+            button.hidden = false;
+            button.addEventListener('click', this._onPersistStorageButtonClick.bind(this), false);
+        }
+
+        if (!this._isPersistentStorageSupported()) { return; }
+
+        const info = document.querySelector('#storage-persistent-info');
+        if (info !== null) { info.hidden = false; }
+
+        const isStoragePeristent = await this.isStoragePeristent();
+        this._updateCheckbox(isStoragePeristent);
+    }
+
+    async isStoragePeristent() {
+        try {
+            return await navigator.storage.persisted();
+        } catch (e) {
+            // NOP
+        }
+        return false;
+    }
+
+    // Private
+
+    _onPersistentStorageCheckboxChange(e) {
+        const node = e.currentTarget;
+        if (node.checked) {
+            node.checked = false;
+            this._attemptPersistStorage();
+        } else {
+            node.checked = true;
+        }
+    }
+
+    _onPersistStorageButtonClick() {
+        const {checked} = this._persistentStorageCheckbox;
+        if (checked) { return; }
+        this._persistentStorageCheckbox.checked = !checked;
+        this._persistentStorageCheckbox.dispatchEvent(new Event('change'));
+    }
+
+    async _attemptPersistStorage() {
+        let isStoragePeristent = false;
+        try {
+            isStoragePeristent = await navigator.storage.persist();
+        } catch (e) {
+            // NOP
+        }
+
+        this._updateCheckbox(isStoragePeristent);
+
+        const node = document.querySelector('#storage-persistent-fail-warning');
+        if (node !== null) { node.hidden = isStoragePeristent; }
+
+        yomichan.trigger('storageChanged');
+    }
+
+    _isPersistentStorageSupported() {
+        return isObject(navigator.storage) && typeof navigator.storage.persist === 'function';
+    }
+
+    _updateCheckbox(isStoragePeristent) {
+        this._persistentStorageCheckbox.checked = isStoragePeristent;
+        this._persistentStorageCheckbox.readOnly = isStoragePeristent;
+    }
+}