package gnarlring

import "testing"

func TestCommitmentFrameRoundTrip(t *testing.T) {
	pk, _ := NTRUKeyGen()
	cc := NewChildCommitment(17, pk, nil)

	data := MarshalCommitmentFrame(cc)
	if len(data) != CommitmentFrameSize {
		t.Fatalf("frame size = %d, want %d", len(data), CommitmentFrameSize)
	}

	cc2 := UnmarshalCommitmentFrame(data)
	if cc2 == nil {
		t.Fatal("UnmarshalCommitmentFrame returned nil")
	}
	if cc2.Index != cc.Index {
		t.Fatalf("index mismatch: %d vs %d", cc2.Index, cc.Index)
	}
	if !Equal(cc2.PubKey, cc.PubKey) {
		t.Fatal("PubKey mismatch")
	}
	if !Equal(cc2.W, cc.W) {
		t.Fatal("W mismatch")
	}
}

func TestEpochFrameRoundTrip(t *testing.T) {
	pkCoord, skCoord := NTRUKeyGen()
	es := StartEpoch(42, pkCoord)

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

	data := MarshalEpochFrame(es)
	if len(data) != EpochFrameSize {
		t.Fatalf("epoch frame size = %d, want %d", len(data), EpochFrameSize)
	}

	es2 := UnmarshalEpochFrame(data)
	if es2 == nil {
		t.Fatal("UnmarshalEpochFrame returned nil")
	}
	if es2.Counter != es.Counter {
		t.Fatalf("counter mismatch")
	}
	if !Equal(es2.Coordinator.H, pkCoord.H) {
		t.Fatal("coordinator PK mismatch")
	}
	if !es2.IsFinalized() {
		t.Fatal("epoch should be finalized after unmarshal")
	}
	if !es2.Verify(pkCoord, []byte("frame-test")) {
		t.Fatal("epoch verification after unmarshal failed")
	}
}

func TestEpochCheckFrameRoundTrip(t *testing.T) {
	pkCoord, skCoord := NTRUKeyGen()
	es := StartEpoch(99, pkCoord)

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

	data := MarshalEpochCheckFrame(es)
	if len(data) != EpochCheckFrameSize {
		t.Fatalf("check frame size = %d, want %d", len(data), EpochCheckFrameSize)
	}

	cf, err := UnmarshalEpochCheckFrame(data)
	if err != nil {
		t.Fatal(err)
	}
	if cf.Counter != es.Counter {
		t.Fatalf("counter mismatch")
	}
	if !Equal(cf.PK, es.Coordinator.H) {
		t.Fatal("pk mismatch")
	}
}

func TestUnmarshalShortFrames(t *testing.T) {
	if UnmarshalCommitmentFrame([]byte{0, 0}) != nil {
		t.Fatal("short commitment frame should return nil")
	}
	if UnmarshalEpochFrame([]byte{0, 0}) != nil {
		t.Fatal("short epoch frame should return nil")
	}
	_, err := UnmarshalEpochCheckFrame([]byte{0, 0})
	if err == nil {
		t.Fatal("short check frame should return error")
	}
}