import { decrypt, deriveSharedSecret, encrypt, generateKeyPair } from './cipher'

describe('Cipher', () => {
	describe('generateKeyPair', () => {
		it('should generate a unique key pair on each call', async () => {
			const firstPublicKey = (await generateKeyPair()).publicKey
			const secondPublicKey = (await generateKeyPair()).publicKey

			expect(firstPublicKey).not.toBe(secondPublicKey)
		})
	})

	describe('deriveSharedSecret', () => {
		it('should derive a shared secret successfully', async () => {
			const ownKeyPair = await generateKeyPair()
			const peerKeyPair = await generateKeyPair()

			const sharedSecret = await deriveSharedSecret(ownKeyPair.privateKey, peerKeyPair.publicKey)
			expect(sharedSecret).toBeDefined()
		})
	})

	describe('encrypt and decrypt', () => {
		it('should encrypt and decrypt a message successfully', async () => {
			const ownKeyPair = await generateKeyPair()
			const peerKeyPair = await generateKeyPair()

			const sharedSecret = await deriveSharedSecret(ownKeyPair.privateKey, peerKeyPair.publicKey)
			const sharedSecretDerivedByPeer = await deriveSharedSecret(peerKeyPair.privateKey, ownKeyPair.publicKey)

			const plaintext = 'This is a secret message'
			const encryptedMessage = await encrypt(sharedSecret, plaintext)
			const decryptedText = await decrypt(sharedSecretDerivedByPeer, encryptedMessage)

			expect(decryptedText).toBe(plaintext)
		})

		it('should throw an error when decrypting with a different shared secret', async () => {
			const ownKeyPair = await generateKeyPair()
			const peerKeyPair = await generateKeyPair()

			const sharedSecret = await deriveSharedSecret(ownKeyPair.privateKey, peerKeyPair.publicKey)

			const plaintext = 'This is a secret message'

			const encryptedMessage = await encrypt(sharedSecret, plaintext)

			// generate new keypair on otherKeyManager and use it to derive different shared secret
			const sharedSecretDerivedByPeer = await deriveSharedSecret(peerKeyPair.privateKey, peerKeyPair.publicKey)

			// Attempting to decrypt with a different shared secret
			await expect(decrypt(sharedSecretDerivedByPeer, encryptedMessage)).rejects.toThrow(
				'The operation failed for an operation-specific reason',
			)
		})
	})
})