package listing

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

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

func TestGetAll(t *testing.T) {
	mock := NewRepositoryMock()
	s := New(mock)
	listings, err := s.GetAll()
	if err != nil {
		t.Error(err.Error())
	}

	if len(listings) != 3 {
		t.Errorf("Listings lengths don't match. Have %d, want 3",
			len(listings))
	}
}

func TestGetAllWithError(t *testing.T) {
	mock := &RepositoryMock{err: errors.New("db exploded")}
	s := New(mock)
	listings, err := s.GetAll()

	if err == nil {
		t.Error("No error returned from faulty GetAll call")
	}

	if listings != nil {
		t.Error("Listings not nil when returned from faulty GetAll call")
	}
}

func TestGetByCategory(t *testing.T) {
	mock := NewRepositoryMock()
	s := New(mock)

	listings, err := s.GetByCategory("audi")
	if err != nil {
		t.Error(err.Error())
	}

	if len(listings) != 1 {
		t.Errorf("Listings by category have wrong length. Have %d, want %d",
			len(listings), 1)
	}
	if !slices.Contains(listings[0].category, "audi") {
		t.Errorf("Returned listing has wrong category. Have %s, want audi",
			listings[0].category)
	}
}

func TestGetByCategoryNoMatches(t *testing.T) {
	mock := &RepositoryMock{}
	s := New(mock)

	listings, err := s.GetByCategory("nonexistantcategory")
	if err != nil {
		t.Error(err.Error())
	}

	if listings != nil {
		t.Error("Listings should be nil if no category matches")
	}
}

func TestGetByCategoryWithError(t *testing.T) {
	mock := &RepositoryMock{err: errors.New("datacenter hit by asteroid")}
	s := New(mock)

	listings, err := s.GetByCategory("mercedes")
	if err == nil {
		t.Error("Error nil when GetByCategory failed")
	}

	if listings != nil {
		t.Error("Listings not nil when GetByCategory failed")
	}
}