//go:build windows

// Package dialog wraps the handful of Win32 message boxes ipswap needs.
//
// This is raw user32 rather than a GUI toolkit on purpose: the fast path must
// stay native and dependency-free, and a confirmation prompt is the only
// blocking UI the tray side has.
package dialog

import (
	"syscall"
	"unsafe"
)

var (
	user32      = syscall.NewLazyDLL("user32.dll")
	messageBoxW = user32.NewProc("MessageBoxW")
)

// MessageBoxW uType flags.
const (
	mbOK              = 0x00000000
	mbOKCancel        = 0x00000001
	mbYesNo           = 0x00000004
	mbIconError       = 0x00000010
	mbIconQuestion    = 0x00000020
	mbIconWarning     = 0x00000030
	mbIconInformation = 0x00000040
	// The tray has no window to own the dialog, so without TOPMOST the box can
	// open behind whatever is focused and look like a hang.
	mbSetForeground = 0x00010000
	mbTopMost       = 0x00040000
)

// MessageBoxW return values.
const (
	idOK  = 1
	idYes = 6
)

func show(title, text string, flags uint32) int {
	t, err := syscall.UTF16PtrFromString(text)
	if err != nil {
		return 0
	}
	c, err := syscall.UTF16PtrFromString(title)
	if err != nil {
		return 0
	}
	ret, _, _ := messageBoxW.Call(
		0,
		uintptr(unsafe.Pointer(t)),
		uintptr(unsafe.Pointer(c)),
		uintptr(flags|mbSetForeground|mbTopMost),
	)
	return int(ret)
}

// Confirm asks a yes/no question and reports whether the user said yes.
func Confirm(title, text string) bool {
	return show(title, text, mbYesNo|mbIconQuestion) == idYes
}

// Info shows a plain acknowledgement box.
func Info(title, text string) {
	show(title, text, mbOK|mbIconInformation)
}

// Error shows a failure. The caller is expected to include the raw netsh
// output — that text is the only diagnostic the user has on site.
func Error(title, text string) {
	show(title, text, mbOK|mbIconError)
}

// ErrorWithRetryAsAdmin reports a failure and offers to relaunch elevated.
// It reports whether the user accepted.
func ErrorWithRetryAsAdmin(title, text string) bool {
	return show(title, text+"\n\nRelaunch ipswap as administrator and try again?",
		mbOKCancel|mbIconWarning) == idOK
}