chore: rename aelis to freya (#122)

apps/freya-backend/src/lib/crypto.test.ts

@@ -0,0 +1,62 @@
+import { describe, expect, test } from "bun:test"
+import { randomBytes } from "node:crypto"
+
+import { CredentialEncryptor } from "./crypto.ts"
+
+const TEST_KEY = randomBytes(32).toString("base64")
+
+describe("CredentialEncryptor", () => {
+	const encryptor = new CredentialEncryptor(TEST_KEY)
+
+	test("round-trip with simple string", () => {
+		const plaintext = "hello world"
+		const encrypted = encryptor.encrypt(plaintext)
+		expect(encryptor.decrypt(encrypted)).toBe(plaintext)
+	})
+
+	test("round-trip with JSON credentials", () => {
+		const credentials = JSON.stringify({
+			accessToken: "ya29.a0AfH6SMB...",
+			refreshToken: "1//0dx...",
+			expiresAt: "2025-12-01T00:00:00Z",
+		})
+		const encrypted = encryptor.encrypt(credentials)
+		expect(encryptor.decrypt(encrypted)).toBe(credentials)
+	})
+
+	test("round-trip with empty string", () => {
+		const encrypted = encryptor.encrypt("")
+		expect(encryptor.decrypt(encrypted)).toBe("")
+	})
+
+	test("round-trip with unicode", () => {
+		const plaintext = "日本語テスト 🔐"
+		const encrypted = encryptor.encrypt(plaintext)
+		expect(encryptor.decrypt(encrypted)).toBe(plaintext)
+	})
+
+	test("each encryption produces different ciphertext (unique IV)", () => {
+		const plaintext = "same input"
+		const a = encryptor.encrypt(plaintext)
+		const b = encryptor.encrypt(plaintext)
+		expect(a).not.toEqual(b)
+		expect(encryptor.decrypt(a)).toBe(plaintext)
+		expect(encryptor.decrypt(b)).toBe(plaintext)
+	})
+
+	test("tampered ciphertext throws", () => {
+		const encrypted = encryptor.encrypt("secret")
+		encrypted[13]! ^= 0xff
+		expect(() => encryptor.decrypt(encrypted)).toThrow()
+	})
+
+	test("truncated data throws", () => {
+		expect(() => encryptor.decrypt(Buffer.alloc(10))).toThrow("Encrypted data is too short")
+	})
+
+	test("throws when key is wrong length", () => {
+		expect(() => new CredentialEncryptor(Buffer.from("too-short").toString("base64"))).toThrow(
+			"must be 32 bytes",
+		)
+	})
+})