From afd8717819a47a7cbbe8eebf51b7723f44438add Mon Sep 17 00:00:00 2001
From: RomaRoma? <friciu.robert09@gmail.com>
Date: Mon, 4 May 2026 11:30:08 +0200
Subject: [PATCH] Add From JSFuck operation

---
 src/core/config/Categories.json       |  3 +-
 src/core/operations/FromJSFuck.mjs    | 53 +++++++++++++++++++++++++++
 tests/operations/tests/FromJSFuck.mjs |  0
 3 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 src/core/operations/FromJSFuck.mjs
 create mode 100644 tests/operations/tests/FromJSFuck.mjs

diff --git a/src/core/config/Categories.json b/src/core/config/Categories.json
index ab1dafb0..9fea4054 100644
--- a/src/core/config/Categories.json
+++ b/src/core/config/Categories.json
@@ -501,7 +501,8 @@
             "BSON deserialise",
             "To MessagePack",
             "From MessagePack",
-            "Render Markdown"
+            "Render Markdown",
+            "From JSFuck"
         ]
     },
     {
diff --git a/src/core/operations/FromJSFuck.mjs b/src/core/operations/FromJSFuck.mjs
new file mode 100644
index 00000000..b50c1973
--- /dev/null
+++ b/src/core/operations/FromJSFuck.mjs
@@ -0,0 +1,53 @@
+/**
+ * @author Roma476 [friciu.robert09@gmail.com]
+ * @copyright Crown Copyright 2026
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation.mjs";
+import OperationError from "../errors/OperationError.mjs";
+
+/**
+ * From JSFuck operation
+ */
+class FromJSFuck extends Operation {
+
+    /**
+     * FromJSFuck constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "From JSFuck";
+        this.module = "Default";
+        this.description = "Decodes JSFuck encoded JavaScript. JSFuck uses only 6 characters: <code>[</code>, <code>]</code>, <code>(</code>, <code>)</code>, <code>!</code> and <code>+</code>.<br><br>e.g.  <code>[][(![]+[])[+[]]+...]</code> becomes <code>alert(1)</code>";
+        this.infoURL = "https://wikipedia.org/wiki/JSFuck"; 
+        this.inputType = "string";
+        this.outputType = "string";
+        this.args = [];
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        // Input Validation
+        for (let i = 0; i < input.length; i++) {
+            const char = input[i];
+            if (!["[", "]", "(", ")", "!", "+"].includes(char)) {
+                throw new OperationError(`Invalid character at position ${i}: ${char}`);
+            }
+        }
+
+        try {
+            return String(Function('"use strict"; return (' + input + ')')());
+        } catch (err) {
+            throw new OperationError("Unable to decode JSFuck: " + err.message);
+        }
+    }
+
+}
+
+export default FromJSFuck;
diff --git a/tests/operations/tests/FromJSFuck.mjs b/tests/operations/tests/FromJSFuck.mjs
new file mode 100644
index 00000000..e69de29b