package lobby_test

import (
	"context"
	"sync/atomic"
	"testing"

	"github.com/google/uuid"

	"git.sunturtle.xyz/studio/shotgun/lobby"
	"git.sunturtle.xyz/studio/shotgun/player"
)

func TestQueue(t *testing.T) {
	const N = 1000 // must be even
	games := make([]lobby.GameID, 0, N)
	ch := make(chan lobby.GameID)
	l := lobby.New()
	for i := 0; i < 100; i++ {
		games = games[:0]
		var dealers, challs atomic.Int32
		for i := 0; i < N; i++ {
			i := i
			go func() {
				id, _, deal := l.Queue(context.Background(), player.ID{UUID: uuid.UUID{uint8(i), uint8(i >> 8)}})
				if deal {
					dealers.Add(1)
				} else {
					challs.Add(1)
				}
				ch <- id
			}()
		}
		for i := 0; i < N; i++ {
			games = append(games, <-ch)
		}
		// Every unique game ID should appear exactly twice.
		counts := make(map[lobby.GameID]int, N/2)
		for _, id := range games {
			counts[id]++
		}
		for id, c := range counts {
			if c != 2 {
				t.Errorf("game %v appears %d times", id, c)
			}
		}
		// The number of dealers must match the number of challengers.
		if dealers.Load() != challs.Load() {
			t.Errorf("%d dealers != %d challengers", dealers.Load(), challs.Load())
		}
	}
}