package main

import (
	"fmt"
	"syscall"
	"unsafe"

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

func example() {
	// Create pipes for stdin and stdout
	var stdInRead, stdInWrite, stdOutRead, stdOutWrite windows.Handle
	sa := &windows.SecurityAttributes{Length: uint32(unsafe.Sizeof(windows.SecurityAttributes{})), InheritHandle: 1}

	err := windows.CreatePipe(&stdInRead, &stdInWrite, sa, 0)
	if err != nil {
		fmt.Println("Error creating stdin pipe:", err)
		return
	}
	defer windows.CloseHandle(stdInRead)
	defer windows.CloseHandle(stdInWrite)

	err = windows.CreatePipe(&stdOutRead, &stdOutWrite, sa, 0)
	if err != nil {
		fmt.Println("Error creating stdout pipe:", err)
		return
	}
	defer windows.CloseHandle(stdOutRead)
	defer windows.CloseHandle(stdOutWrite)

	// Set the pipe to non-blocking mode
	mode := uint32(windows.PIPE_NOWAIT)
	err = windows.SetNamedPipeHandleState(stdInWrite, &mode, nil, nil)
	if err != nil {
		fmt.Println("Error setting stdin pipe to non-blocking:", err)
		return
	}
	err = windows.SetNamedPipeHandleState(stdOutRead, &mode, nil, nil)
	if err != nil {
		fmt.Println("Error setting stdout pipe to non-blocking:", err)
		return
	}

	// Prepare process startup info
	si := &windows.StartupInfo{
		Cb:        uint32(unsafe.Sizeof(windows.StartupInfo{})),
		Flags:     windows.STARTF_USESTDHANDLES,
		StdInput:  stdInRead,
		StdOutput: stdOutWrite,
		StdErr:    stdOutWrite,
	}
	pi := &windows.ProcessInformation{}

	// Create the process
	cmd := "cmd.exe"
	err = windows.CreateProcess(
		nil,
		syscall.StringToUTF16Ptr(cmd),
		nil,
		nil,
		true,
		0,
		nil,
		nil,
		si,
		pi,
	)
	if err != nil {
		fmt.Println("Error creating process:", err)
		return
	}
	defer windows.CloseHandle(pi.Process)
	defer windows.CloseHandle(pi.Thread)

	// Write to the process
	message := "echo Hello, World!\r\n"
	var written uint32
	err = windows.WriteFile(stdInWrite, []byte(message), &written, nil)
	if err != nil {
		fmt.Println("Error writing to process:", err)
		return
	}

	// Read from the process
	buffer := make([]byte, 1024)
	var read uint32
	err = windows.ReadFile(stdOutRead, buffer, &read, nil)
	if err != nil && err != windows.ERROR_NO_DATA {
		fmt.Println("Error reading from process:", err)
		return
	}

	fmt.Printf("Output: %s", buffer[:read])

	// Wait for the process to finish
	windows.WaitForSingleObject(pi.Process, windows.INFINITE)
}