package kdbx

import (
	"encoding/hex"
	"testing"
)

// RFC 7693 appendix A, and the standard unkeyed vectors for the empty input
// and "abc".
func TestBlake2bVectors(t *testing.T) {
	for _, tc := range []struct {
		in, want string
		outLen   int
	}{
		{"", "786a02f742015903c6c6fd852552d272912f4740e15847618a86e217f71f5419" +
			"d25e1031afee585313896444934eb04b903a685b1448b755d56f701afe9be2ce", 64},
		{"abc", "ba80a53f981c4d0d6a2797b69f12f6e94c212f14685ac4b74b12bb6fdbffa2d1" +
			"7d87c5392aab792dc252d5de4533cc9518d38aa8dbf1925ab92386edd4009923", 64},
		{"abc", "bddd813c634239723171ef3fee98579b94964e3bb1cb3e427262c8c068d52319", 32},
	} {
		got := hex.EncodeToString(blake2bSum(tc.outLen, []byte(tc.in)))
		if got != tc.want {
			t.Errorf("blake2b-%d(%q) =\n%s\nwant\n%s", tc.outLen*8, tc.in, got, tc.want)
		}
	}
}

func TestBlake2bKeyed(t *testing.T) {
	// RFC 7693 appendix A uses a 64-byte key of 0x00..0x3f with input 0x00.
	key := make([]byte, 64)
	for i := range key {
		key[i] = byte(i)
	}
	h := newBlake2b(64, key)
	h.Write([]byte{0x00})
	want := "961f6dd1e4dd30f63901690c512e78e4b45e4742ed197c3c5e45c549fd25f2e4" +
		"187b0bc9fe30492b16b0d0bc4ef9b0f34c7003fac09a5ef1532e69430234cebd"
	if got := hex.EncodeToString(h.Sum()); got != want {
		t.Fatalf("keyed blake2b =\n%s\nwant\n%s", got, want)
	}
}

func TestBlake2bAcrossWriteBoundaries(t *testing.T) {
	data := make([]byte, 300)
	for i := range data {
		data[i] = byte(i)
	}
	want := hex.EncodeToString(blake2bSum(64, data))
	h := newBlake2b(64, nil)
	for _, n := range []int{1, 127, 1, 128, 43} {
		h.Write(data[:n])
		data = data[n:]
	}
	if got := hex.EncodeToString(h.Sum()); got != want {
		t.Fatal("chunked writes differ from a single write")
	}
}