added flag logic and encryption

Author: MatanelGordon

src/logic/flagDecorator.spec.ts

@@ -0,0 +1,13 @@
+import { createFlag, stripFlag } from './flagDecorator';
+
+describe('Flag Decorator', () => {
+it('should strip flag and leave the content', () => {
+const flag = createFlag('test');
+expect(stripFlag(flag)).toEqual('test');
+});
+
+it('should throw error for splitting invalid flag', () => {
+const flag = 'test';
+expect(() => stripFlag(flag)).toThrow();
+});
+});

src/logic/flagDecorator.ts

@@ -0,0 +1,15 @@
+import { removePadding } from '@utils/padding';
+
+export type Flag = `flag{${string}}`;
+
+export const createFlag = (content: string): Flag => `flag{${content}}`;
+
+export const isFlag = (str: string): str is Flag =>
+str.startsWith('flag{') && str.endsWith('}');
+
+export const stripFlag = (flag: string) => {
+if (!isFlag(flag))
+throw new Error(`StripFlagError - invalid flag - ${flag}`);
+
+return removePadding(flag, 'flag{', '}');
+};

src/logic/flagEncryption.spec.ts

@@ -0,0 +1,2 @@
+describe('flagEncryption', () => {
+})

src/logic/flagEncryption.ts

@@ -0,0 +1,12 @@
+import { stripFlag } from '@logic/flagDecorator';
+
+const PAD_START = 'encrypted{';
+const PAD_END = '}';
+
+export const encryptFlag = (flag: string) => {
+const flagContent = stripFlag(flag);
+
+return ;
+};
+
+export const decryptFlag = (encryptedFlag: string) => {};