package lobby

import (
	"strings"
	"testing"
	"time"
)

func TestAddDriver(t *testing.T) {
	s := NewService()
	d, err := s.AddDriver("d1", "Alice", "RU")
	if err != nil {
		t.Fatalf("AddDriver: %v", err)
	}
	if d.Status != DriverStatusIdle {
		t.Errorf("expected idle, got %s", d.Status)
	}
	if d.Name != "Alice" {
		t.Errorf("name: got %s", d.Name)
	}
}

func TestCreateRaceValidates(t *testing.T) {
	s := NewService()
	_, _ = s.AddDriver("d1", "Alice", "")
	tests := []struct {
		name string
		opts CreateRaceOptions
		want string // substring of error message or "" for OK
	}{
		{"empty name", CreateRaceOptions{Name: "", MaxCars: 2, Laps: 1}, "name required"},
		{"max cars too low", CreateRaceOptions{Name: "r", MaxCars: 0, Laps: 1}, ""}, // defaults
		{"max cars too high", CreateRaceOptions{Name: "r", MaxCars: 9, Laps: 1}, "max_cars must be"},
		{"no laps and no time", CreateRaceOptions{Name: "r", MaxCars: 2}, "laps or time_limit_s"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			_, err := s.CreateRace(tt.opts)
			if tt.want == "" && err != nil {
				t.Fatalf("expected ok, got %v", err)
			}
			if tt.want != "" && err == nil {
				t.Fatalf("expected error containing %q, got nil", tt.want)
			}
			if tt.want != "" && err != nil && !strings.Contains(err.Error(), tt.want) {
				t.Fatalf("error %q does not contain %q", err.Error(), tt.want)
			}
		})
	}
}

func TestCreateRaceEmpty(t *testing.T) {
	s := NewService()
	r, err := s.CreateRace(CreateRaceOptions{
		Name:    "open",
		TrackID: "default",
		MaxCars: 4,
		Laps:    5,
	})
	if err != nil {
		t.Fatalf("CreateRace: %v", err)
	}
	if r.Status != RaceStatusLobby {
		t.Errorf("status: got %s", r.Status)
	}
	if len(r.DriverIDs) != 0 {
		t.Errorf("expected empty drivers, got %d", len(r.DriverIDs))
	}
	if r.TrackID != "default" {
		t.Errorf("track: got %s", r.TrackID)
	}
}

func TestQuickPlayJoinsFirstRace(t *testing.T) {
	s := NewService()
	_, _ = s.AddDriver("d1", "Alice", "")
	_, _ = s.AddDriver("d2", "Bob", "")
	car1, car2 := "car-1", "car-2"
	_ = s.SelectCar("d1", &car1)
	_ = s.SelectCar("d2", &car2)
	r1, _ := s.QuickPlay("d1", 4)
	r2, err := s.QuickPlay("d2", 4)
	if err != nil {
		t.Fatalf("QuickPlay d2: %v", err)
	}
	if r2.ID != r1.ID {
		t.Errorf("expected to join %s, got %s", r1.ID, r2.ID)
	}
	if len(r2.DriverIDs) != 2 {
		t.Errorf("expected 2 drivers, got %d", len(r2.DriverIDs))
	}
}

func TestSubscribeReceivesSnapshot(t *testing.T) {
	s := NewService()
	ch, cancel := s.Subscribe()
	defer cancel()
	// Subscribe pushes initial snapshot.
	select {
	case ev := <-ch:
		if ev.kind != "snapshot" {
			t.Fatalf("first event: kind=%s", ev.kind)
		}
	case <-time.After(time.Second):
		t.Fatal("no initial snapshot")
	}
}

func TestSubscribeReceivesRaceCreated(t *testing.T) {
	s := NewService()
	ch, cancel := s.Subscribe()
	defer cancel()
	<-ch // drain initial snapshot
	_, _ = s.AddDriver("d1", "Alice", "")
	select {
	case ev := <-ch:
		if ev.kind != "driver_joined" {
			t.Fatalf("expected driver_joined, got %s", ev.kind)
		}
	case <-time.After(time.Second):
		t.Fatal("no event after AddDriver")
	}
}