package usync

import "time"
import "errors"
import "testing"

func TestGate(test *testing.T) {
	gate := NewGate[int]()
	go func() {
		for number := range 21 {
			test.Log("send", number)
			gate.Send(number)
		}
		test.Log("send done")
	}()
	for correct := range 21 {
		got := <- gate.Receive()
		test.Log("RECV", correct, got)
		if correct != got {
			test.Fatal("RECV not equal")
		}
	}
	test.Log("RECV done")
}

func TestGateCloseEarly(test *testing.T) {
	gate := NewGate[int]()
	sendDone := make(chan struct { })
	go func() {
		for number := range 21 {
			test.Log("send", number)
			gate.Send(number)
		}
		test.Log("send done")
		close(sendDone)
	}()
	for correct := range 15 {
		got := <- gate.Receive()
		test.Log("RECV", correct, got)
		if correct != got {
			test.Fatal("RECV not equal")
		}
	}
	test.Log("RECV done, closing gate... DOOR STUCK!! PLS I BEG OF YOU!!")
	gate.Close()
	test.Log("RECV closed gate yay :)))")
	timeout := time.NewTimer(time.Second * 4)
	select {
	case <- sendDone:
	case <- timeout.C:
		test.Fatal("timed out waiting for sender goroutine to stop")
	}
}

func TestGateCloseIdempotent(test *testing.T) {
	gate := NewGate[int]()
	err := gate.Close()
	if err != nil { test.Fatal(err) }
	err = gate.Close()
	if !errors.Is(err, ErrAlreadyClosed) {
		test.Fatal("wrong error: ", err)
	}
}