package licensing

import (
	"errors"
	"strings"
	"testing"
)

func TestDeriveMachineHashCanonicalizesGUID(t *testing.T) {
	const want = "0922bbbd8c44576d1afa6fe1309615963493cf2e1c4fddda20d2cb3ecb3c1dff"

	got, err := DeriveMachineHash("  6F9619FF-8B86-D011-B42D-00C04FC964FF\t", 0x1a2b3c4d)
	if err != nil {
		t.Fatalf("DeriveMachineHash() error = %v", err)
	}
	if got != want {
		t.Fatalf("DeriveMachineHash() = %q, want %q", got, want)
	}
	if len(got) != 64 || strings.ToLower(got) != got {
		t.Fatalf("DeriveMachineHash() = %q, want 64 lowercase hexadecimal characters", got)
	}
}

func TestDeriveMachineHashChangesForVolumeSerial(t *testing.T) {
	guid := "6f9619ff-8b86-d011-b42d-00c04fc964ff"
	first, err := DeriveMachineHash(guid, 1)
	if err != nil {
		t.Fatalf("DeriveMachineHash(first) error = %v", err)
	}
	second, err := DeriveMachineHash(guid, 2)
	if err != nil {
		t.Fatalf("DeriveMachineHash(second) error = %v", err)
	}
	if first == second {
		t.Fatal("DeriveMachineHash() did not include the volume serial number")
	}
}

func TestDeriveMachineHashRejectsInvalidGUID(t *testing.T) {
	tests := []string{
		"",
		"6f9619ff8b86-d011-b42d-00c04fc964ff",
		"6f9619ff-8b86-d011-b42d-00c04fc964fg",
		"6f9619ff-8b86-d011-b42d-00c04fc964f\x00",
		"6f9619ff-8b86-d011-b42d-00c04fc964fé",
	}
	for _, machineGUID := range tests {
		_, err := DeriveMachineHash(machineGUID, 1)
		if !errors.Is(err, ErrInvalidMachineGUID) {
			t.Fatalf("DeriveMachineHash(%q) error = %v, want ErrInvalidMachineGUID", machineGUID, err)
		}
	}
}