package gnarlring

import (
	"crypto/rand"
	"testing"

	"git.smesh.lol/gnarl-hamadryad/crypto"
)

func TestInsurgeWireRoundTrip(t *testing.T) {
	// Derive a shared secret for the wire channel.
	var secret crypto.Hamadryad
	rand.Read(secret[:])

	var identity crypto.GnarlMid
	rand.Read(identity[:])

	var nonce [crypto.GnarlNonceLen]byte
	rand.Read(nonce[:])

	// Test commitment frame.
	pk, _ := NTRUKeyGen()
	cc := NewChildCommitment(7, pk, nil)
	pkt := SealCommitment(secret, identity, nonce, cc)
	cc2, err := OpenCommitment(secret, pkt)
	if err != nil {
		t.Fatal(err)
	}
	if cc2.Index != cc.Index || !Equal(cc2.W, cc.W) {
		t.Fatal("commitment round-trip failed")
	}

	// Test epoch frame.
	pkCoord, skCoord := NTRUKeyGen()
	es := StartEpoch(1, pkCoord)
	for i := 0; i < N; i++ {
		es.AddCommitment(NewChildCommitment(i, skCoord.PK, nil))
	}
	es.Finalize(skCoord, []byte("wire-test"))

	pkt2 := SealEpoch(secret, identity, nonce, es)
	es2, err := OpenEpoch(secret, pkt2)
	if err != nil {
		t.Fatal(err)
	}
	if es2.Counter != es.Counter {
		t.Fatal("epoch round-trip counter mismatch")
	}
}

func TestInsurgeWireWrongType(t *testing.T) {
	var secret crypto.Hamadryad
	rand.Read(secret[:])
	var identity crypto.GnarlMid
	rand.Read(identity[:])
	var nonce [crypto.GnarlNonceLen]byte

	pk, _ := NTRUKeyGen()
	cc := NewChildCommitment(0, pk, nil)

	pkt := SealCommitment(secret, identity, nonce, cc)
	// Try to open as wrong type.
	_, err := OpenEpoch(secret, pkt)
	if err == nil {
		t.Fatal("should reject commitment frame when opening as epoch")
	}
}

func TestInsurgeWireTampered(t *testing.T) {
	var secret crypto.Hamadryad
	rand.Read(secret[:])
	var identity crypto.GnarlMid
	rand.Read(identity[:])
	var nonce [crypto.GnarlNonceLen]byte
	rand.Read(nonce[:])

	pk, _ := NTRUKeyGen()
	cc := NewChildCommitment(0, pk, nil)
	pkt := SealCommitment(secret, identity, nonce, cc)

	// Tamper with the ciphertext.
	pkt.Ciphertext[0] ^= 0xFF
	_, err := OpenCommitment(secret, pkt)
	if err == nil {
		t.Fatal("should reject tampered commitment frame")
	}
}

func TestInsurgeWireEpochCheckFrame(t *testing.T) {
	var secret crypto.Hamadryad
	rand.Read(secret[:])
	var identity crypto.GnarlMid
	rand.Read(identity[:])
	var nonce [crypto.GnarlNonceLen]byte

	pkCoord, skCoord := NTRUKeyGen()
	es := StartEpoch(42, pkCoord)
	for i := 0; i < N; i++ {
		es.AddCommitment(NewChildCommitment(i, skCoord.PK, nil))
	}
	es.Finalize(skCoord, []byte("check-test"))

	pkt := SealEpochCheck(secret, identity, nonce, es)
	cf, err := OpenEpochCheck(secret, pkt)
	if err != nil {
		t.Fatal(err)
	}
	if cf.Counter != es.Counter {
		t.Fatal("check frame round-trip counter mismatch")
	}
}