chore: add custom cursor, add config system

src/lib/crypto.ts

@@ -0,0 +1,37 @@
+import cryptojs from 'crypto-js';
+
+export class Crypto {
+  private key: cryptojs.lib.WordArray;
+  private ivLength: number;
+
+  constructor(key: string, opts?: { ivLength?: number }) {
+    this.key = cryptojs.SHA256(key);
+    this.ivLength = opts?.ivLength ?? 16;
+  }
+
+  encrypt(str: string): string {
+    const iv = cryptojs.lib.WordArray.random(this.ivLength);
+    const encrypted = cryptojs.AES.encrypt(str, this.key, { iv });
+
+    const ivBase64 = iv.toString(cryptojs.enc.Base64);
+    const ctBase64 = encrypted.ciphertext.toString(cryptojs.enc.Base64);
+
+    return `${ivBase64}:${ctBase64}`;
+  }
+
+  decrypt(data: string): string {
+    const [ivBase64, ctBase64] = data.split(':');
+
+    if (!ivBase64 || !ctBase64) throw new Error('Invalid input format');
+
+    const iv = cryptojs.enc.Base64.parse(ivBase64);
+    const ciphertext = cryptojs.enc.Base64.parse(ctBase64);
+
+    const cipherParams = cryptojs.lib.CipherParams.create({
+      ciphertext,
+    });
+
+    const decrypted = cryptojs.AES.decrypt(cipherParams, this.key, { iv });
+    return decrypted.toString(cryptojs.enc.Utf8);
+  }
+}