package cryptoutil

import (
	"bytes"
	"encoding/hex"
	"testing"
)

func mustHex(t *testing.T, s string) []byte {
	t.Helper()
	bytes, err := hex.DecodeString(s)
	if err != nil {
		t.Fatalf("Bad hex %q: %s", s, err)
	}
	return bytes
}

func TestPassword(t *testing.T) {
	const password = "eclair scroll gliding sled shining removed ascend android cheer confetti"
	hash, err := Hash(password)
	if err != nil {
		t.Fatalf("Hash(%q) failed: %s", password, err)
	}
	_, err = CheckPassword(password, hash)
	if err != nil {
		t.Errorf("CheckPassword(%q, %q) failed: %s", password, hash, err)
	}
}

func TestSignature(t *testing.T) {
	key := HMACKey(mustHex(t, "669e06ec457778b9a8133edb0a87ea82c6b141ffbbc63c038da96258175eb35c"))
	msg := []byte("test message")
	signedMsg := key.Sign(msg)
	got, ok := key.Verify(signedMsg)
	if !ok {
		t.Fatalf("Verify(%x) rejected the message", signedMsg)
	}
	if !bytes.Equal(got, msg) {
		t.Errorf("Verify(%x) = %x, want %x", signedMsg, got, msg)
	}
}

func TestEncrypt(t *testing.T) {
	key := EncryptionKey(mustHex(t, "b6de26860e0a39aa134732e58055c06ba028675453f73a6912bc932e58d5743d0e423217f06487d3e96a59980301fcc97dfcc4c6b19765f2947de3c33ab7ef9e"))
	msg := []byte("test message")
	encryptedMsg, err := key.Encrypt(msg)
	if err != nil {
		t.Fatalf("Encrypt(%q) failed: %s", msg, err)
	}
	got, err := key.Decrypt(encryptedMsg)
	if err != nil {
		t.Fatalf("Decrypt(%x) failed: %s", encryptedMsg, err)
	}
	if !bytes.Equal(got, msg) {
		t.Errorf("Decrypt(%x) = %x, want %x", encryptedMsg, got, msg)
	}
}

func TestDeriveKey(t *testing.T) {
	const password = "automaker moisture botch tubular kelp rinse rule giggly donated stock"
	hash, err := Hash(password)
	if err != nil {
		t.Fatalf("Hash(%q) failed: %s", password, err)
	}
	rawKey, err := CheckPassword(password, hash)
	if err != nil {
		t.Fatalf("CheckPassword(%q, %x) failed: %s", password, hash, err)
	}
	key, err := rawKey.EncryptionKey()
	if err != nil {
		t.Fatalf("EncryptionKey() failed: %s", err)
	}
	msg := []byte("test message")
	encryptedMsg, err := key.Encrypt(msg)
	if err != nil {
		t.Fatalf("Encrypt(%q) failed: %s", msg, err)
	}
	got, err := key.Decrypt(encryptedMsg)
	if err != nil {
		t.Fatalf("Decrypt(%x) failed: %s", encryptedMsg, err)
	}
	if !bytes.Equal(got, msg) {
		t.Errorf("Decrypt(%x) = %x, want %x", encryptedMsg, got, msg)
	}
}