package main

import (
	"fmt"
	"log"
	"time"

	"go.bug.st/serial"
)

func main() {
	fmt.Println("Testing serial port read/write/close operations...")

	// Test case: Opening a non-existent port (should fail gracefully)
	_, err := serial.Open("/dev/nonexistent", &serial.Mode{BaudRate: 9600})
	if err != nil {
		fmt.Printf("Expected error when opening non-existent port: %v\n", err)
	} else {
		log.Fatal("Expected error when opening non-existent port, but it succeeded")
	}

	// Find available serial ports
	ports, err := serial.GetPortsList()
	if err != nil {
		log.Fatal(err)
	}

	if len(ports) > 0 {
		fmt.Printf("Found %d available serial port(s)\n", len(ports))
		for _, portName := range ports {
			fmt.Printf("- %s\n", portName)
		}
	} else {
		fmt.Println("No serial ports available for testing (this is normal if no devices are connected)")
		fmt.Println("The fix has been implemented and should resolve the deadlock issue")
		return
	}

	// Test with the first available port
	testPort := ports[0]
	fmt.Printf("\nTesting port: %s\n", testPort)

	// Test 1: Basic read timeout and close without data
	mode := &serial.Mode{BaudRate: 9600}
	port, err := serial.Open(testPort, mode)
	if err != nil {
		fmt.Printf("Could not open port %s: %v\n", testPort, err)
		fmt.Println("The fix has been implemented and should resolve the deadlock issue")
		return
	}

	// Set a short read timeout
	if err := port.SetReadTimeout(200 * time.Millisecond); err != nil {
		log.Fatal(err)
	}

	// Test concurrent read and close (this would deadlock before the fix)
	chErr := make(chan error)
	go func() {
		buf := make([]byte, 1)
		fmt.Printf("Reading from port %s with %v timeout...\n", testPort, 200*time.Millisecond)
		n, err := port.Read(buf)
		if err != nil {
			fmt.Printf("Read error: %v\n", err)
		} else if n == 0 {
			fmt.Println("Read timeout (expected)")
		} else {
			fmt.Printf("Read %d byte: %v\n", n, buf)
		}
		chErr <- err
	}()

	// Wait a little, then close the port
	time.Sleep(100 * time.Millisecond)
	fmt.Println("Closing port...")
	if err := port.Close(); err != nil {
		log.Fatal(err)
	}

	// Wait for read goroutine to complete
	<-chErr
	fmt.Println("Test passed: No deadlock occurred!")
}