package user

import (
	"errors"
	"log/slog"
	"os"
	"testing"

	"golang.org/x/crypto/bcrypt"
)

func TestMain(m *testing.M) {
	slog.SetDefault(slog.New(slog.DiscardHandler))
	os.Exit(m.Run())
}

func newTestUserService(t *testing.T) *Service {
	t.Helper()
	return &Service{repository: newEmptyRepository(), bcryptCost: bcrypt.MinCost}
}

func TestRegisterInputValidateFaultyData(t *testing.T) {
	badInputs := getInvalidRegisterInputs()

	for name, in := range badInputs {
		t.Run(name, func(t *testing.T) {
			err := in.validate()
			if err == nil {
				t.Errorf("bad input got through: %+v", in)
			}
			if !errors.Is(err, ErrInvalidInput) {
				t.Errorf("unexpected error: got %v, want ErrInvalidInput", err)
			}
		})
	}
}

func TestRegisterBadInput(t *testing.T) {
	in := &RegisterInput{}
	s := newTestUserService(t)
	_, err := s.Register(in)
	if err == nil {
		t.Error("no error when registering with faulty input")
	}
}

func TestRegisterExistingUser(t *testing.T) {
	r := newEmptyRepository()
	r.fill()

	badInputs := map[string]RegisterInput{
		"existing username": {
			Username: r.users[0].Username,
			Email:    "thisemaildoesnt@exist.com",
			Phone:    "123321",
			Password: "22332233",
		},
		"existing email": {
			Username: "thisusernamedoesntexist",
			Email:    r.users[0].Email,
			Phone:    "123321",
			Password: "22332233",
		},
	}

	for name, in := range badInputs {
		t.Run(name, func(t *testing.T) {
			s := &Service{repository: r, bcryptCost: bcrypt.MinCost}
			_, err := s.Register(&in)
			if err == nil {
				t.Error("existing user registered")
			}

			if !errors.Is(err, ErrUserExists) {
				t.Errorf("unexpected error: got %v, want ErrUserExists", err)
			}
		})
	}
}

func TestRegisterRepositoryError(t *testing.T) {
	s := &Service{
		repository: &RepositoryMock{err: errors.New("db down")},
		bcryptCost: bcrypt.MinCost,
	}

	in := &RegisterInput{Username: "bob", Email: "b@b.com", Password: "thisissecure"}
	_, err := s.Register(in)

	if err == nil {
		t.Error("register swallowed repository error")
	}

	if errors.Is(err, ErrUserExists) {
		t.Error("repository failure reported as ErrUserExists")
	}
}

func TestSuccessfulRegister(t *testing.T) {
	s := newTestUserService(t)
	in := &RegisterInput{
		Username: "happyuser123",
		Email:    "happyuser@email.com",
		Phone:    "+381233232",
		Password: "supersecretpassword1234",
	}
	usr, err := s.Register(in)
	if err != nil {
		t.Errorf("register with good input failed: %+v", in)
	}

	err = bcrypt.CompareHashAndPassword([]byte(usr.passwordHash), []byte(in.Password))
	if err != nil {
		t.Errorf("hash and password compare error: %v", err)
	}
}

func TestRegisterSameUserTwice(t *testing.T) {
	s := newTestUserService(t)
	in := &RegisterInput{
		Username: "happyuser123",
		Email:    "happyuser@email.com",
		Phone:    "+381233232",
		Password: "supersecretpassword1234",
	}

	s.Register(in)

	_, err := s.Register(in)
	if err == nil {
		t.Errorf("registered same user twice: %+v", in)
	}

	if !errors.Is(err, ErrUserExists) {
		t.Errorf("unexpected error: got %v, want ErrUserExists", err)
	}

}