package crypto

import (
	"github.com/lucas-clemente/quic-go/internal/protocol"
	. "github.com/onsi/ginkgo"
	. "github.com/onsi/gomega"
)

var _ = Describe("NullAEAD using FNV128a", func() {
	aad := []byte("All human beings are born free and equal in dignity and rights.")
	plainText := []byte("They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.")
	hash36 := []byte{0x98, 0x9b, 0x33, 0x3f, 0xe8, 0xde, 0x32, 0x5c, 0xa6, 0x7f, 0x9c, 0xf7}

	It("opens", func() {
		cipherText := append(hash36, plainText...)
		aead := NewNullAEAD(protocol.PerspectiveServer, protocol.Version36)
		res, err := aead.Open(nil, cipherText, 0, aad)
		Expect(err).ToNot(HaveOccurred())
		Expect(res).To(Equal(plainText))
	})

	It("seals", func() {
		aead := NewNullAEAD(protocol.PerspectiveServer, protocol.Version36)
		sealed := aead.Seal(nil, plainText, 0, aad)
		Expect(sealed).To(Equal(append(hash36, plainText...)))
		Expect(sealed).To(HaveLen(len(plainText) + aead.Overhead()))
	})

	It("rejects short ciphertexts", func() {
		aead := NewNullAEAD(protocol.PerspectiveServer, protocol.Version36)
		_, err := aead.Open(nil, nil, 0, nil)
		Expect(err).To(MatchError("NullAEAD: ciphertext cannot be less than 12 bytes long"))
	})

	It("seals in-place", func() {
		aead := NewNullAEAD(protocol.PerspectiveServer, protocol.Version36)
		buf := make([]byte, 6, 12+6)
		copy(buf, []byte("foobar"))
		res := aead.Seal(buf[0:0], buf, 0, nil)
		buf = buf[:12+6]
		Expect(buf[12:]).To(Equal([]byte("foobar")))
		Expect(res[12:]).To(Equal([]byte("foobar")))
	})

	It("fails", func() {
		cipherText := append(append(hash36, plainText...), byte(0x42))
		aead := NewNullAEAD(protocol.PerspectiveServer, protocol.Version36)
		_, err := aead.Open(nil, cipherText, 0, aad)
		Expect(err).To(HaveOccurred())
	})

	Context("including the perspective, for QUIC >= 37", func() {
		var aeadServer AEAD
		var aeadClient AEAD

		BeforeEach(func() {
			aeadServer = NewNullAEAD(protocol.PerspectiveServer, protocol.Version37)
			aeadClient = NewNullAEAD(protocol.PerspectiveClient, protocol.Version37)
		})

		It("opens, for QUIC version >= 37, as a server", func() {
			cipherText := aeadClient.Seal(nil, plainText, 0, aad)
			res, err := aeadServer.Open(nil, cipherText, 0, aad)
			Expect(err).ToNot(HaveOccurred())
			Expect(res).To(Equal([]byte("They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.")))
		})

		It("opens, for QUIC version >= 37, as a client", func() {
			cipherText := aeadServer.Seal(nil, plainText, 0, aad)
			res, err := aeadClient.Open(nil, cipherText, 0, aad)
			Expect(err).ToNot(HaveOccurred())
			Expect(res).To(Equal([]byte("They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.")))
		})
	})
})