package lobby_test

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

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

func TestQueue(t *testing.T) {
	const N = 10000 // must be even
	games := make([]int, 0, N)
	ch := make(chan int)
	pc := make(chan int, N)
	l := lobby.New[int, int]()
	var dealers, challs atomic.Int32
	for i := 0; i < N; i++ {
		i := i
		new := func() int { return i }
		go func() {
			id, j, deal := l.Queue(context.Background(), new, i)
			if deal {
				dealers.Add(1)
			} else {
				challs.Add(1)
			}
			ch <- id
			pc <- j
		}()
	}
	for i := 0; i < N; i++ {
		games = append(games, <-ch)
	}
	// Every unique game ID should appear exactly twice.
	counts := make(map[int]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)
		}
	}
	// Every unique challenger info should appear exactly twice.
	ps := make(map[int]int, N/2)
	for i := 0; i < N; i++ {
		ps[<-pc]++
	}
	// 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())
	}
}