1 files changed, 31 insertions, 4 deletions

diff --git a/data/extensions/jsr@javascriptrestrictor/options_advanced.js b/data/extensions/jsr@javascriptrestrictor/options_advanced.js
index ad36623..cf327d4 100644
--- a/data/extensions/jsr@javascriptrestrictor/options_advanced.js
+++ b/data/extensions/jsr@javascriptrestrictor/options_advanced.js
@@ -20,27 +20,54 @@
 //  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 //
 
-function load_config_to_text() {
+let original_config = undefined;
+document.getElementById("levels-storage-undo").classList.add("hidden");
+
+function load_config_to_text(keep_config = false) {
 	browser.storage.sync.get(null).then(function (item) {
 		document.getElementById("levels-storage-text").value = JSON.stringify(item, null, '\t');
+		if (keep_config) {
+			original_config = item;
+		}
 	});
 }
 
 window.addEventListener("DOMContentLoaded", function() {
-	load_config_to_text();
+	load_config_to_text(true);
 });
 
 document.getElementById("levels-storage-load").addEventListener("click", function() {
 	load_config_to_text();
 });
 
-document.getElementById("levels-storage-save").addEventListener("click", function() {
+document.getElementById("levels-storage-save").addEventListener("click", async function() {
 	try {
-		checkAndSaveConfig(JSON.parse(document.getElementById("levels-storage-text").value));
+		await checkAndSaveConfig(JSON.parse(document.getElementById("levels-storage-text").value));
 	}
 	catch (e) {
 		alert("The configuration is not valid.");
 		return;
 	}
 	load_config_to_text();
+	document.getElementById("levels-storage-undo").classList.remove("hidden");
+});
+
+document.getElementById("levels-storage-reset").addEventListener("click", async function() {
+	await checkAndSaveConfig({});
+	load_config_to_text();
+	document.getElementById("levels-storage-undo").classList.remove("hidden");
+});
+
+document.getElementById("levels-storage-undo").addEventListener("click", async function() {
+	if (original_config !== undefined) {
+		try {
+			let current_config = await browser.storage.sync.get(null);
+			await checkAndSaveConfig(original_config);
+			load_config_to_text();
+			original_config = current_config;
+		}
+		catch (e) {
+			alert("An unexpected error during configuration restore. Please check and fix the configuration manually.");
+		}
+	}
 });