package inotify

import (
	"testing"
	"time"

	"golang.org/x/sys/unix"
)

func TestPollerWithBadFd(t *testing.T) {
	_, err := newPoller(-1)
	if err != unix.EBADF {
		t.Fatalf("Expected EBADF, got: %v", err)
	}
}

func TestPollerWithData(t *testing.T) {
	var tfd [2]int
	err := unix.Pipe(tfd[:])
	if err != nil {
		t.Fatalf("failed to create pipe: %v", err)
	}
	defer func() {
		unix.Close(tfd[0])
		unix.Close(tfd[1])
	}()
	poller, err := newPoller(tfd[0])
	if err != nil {
		t.Fatalf("Failed to create poller: %v", err)
	}
	oks := make(chan bool)
	go func() {
		ok, err := poller.wait()
		if err != nil {
			t.Fatalf("poller failed: %v", err)
		}
		oks <- ok
	}()

	select {
	case <-time.After(1000 * time.Millisecond):
	case <-oks:
		t.Fatalf("poller did not wait")
	}

	msg := "poller"
	buf := []byte(msg)
	_, err = unix.Write(tfd[1], buf)
	if err != nil {
		t.Fatalf("Failed to write to pipe: %v", err)
	}

	ok := <-oks
	if !ok {
		t.Fatalf("expected true")
	}
	buf2 := make([]byte, 2048)
	n, err := unix.Read(tfd[0], buf2)
	if string(buf2[:n]) != msg {
		t.Fatalf("read data error")
	}
}

func TestPollerWithClose(t *testing.T) {
	var tfd [2]int
	err := unix.Pipe(tfd[:])
	if err != nil {
		t.Fatalf("failed to create pipe: %v", err)
	}
	defer func() {
		unix.Close(tfd[0])
	}()
	poller, err := newPoller(tfd[0])
	if err != nil {
		t.Fatalf("Failed to create poller: %v", err)
	}
	unix.Close(tfd[1])
	ok, err := poller.wait()
	if err == nil {
		t.Fatalf("except poller")
	}
	if ok {
		t.Fatalf("expected poller to return true")
	}
}