Battery Status Informer

#pragma comment(linker,"/MERGE:.rdata=.text")
#pragma comment(linker,"/MERGE:.data=.text")
#pragma comment(linker,"/SECTION:.text,ERW,512")
#pragma comment(linker,"/Od")
#pragma comment(linker,"/NODEFAULTLIB")
#pragma comment(linker,"/CLRUNMANAGEDCODECHECK:NO")
#pragma comment(linker,"/MANIFEST:NO")
#pragma comment(linker,"/MANIFESTUAC:NO")
#pragma comment(linker,"/GS-")
#pragma comment(linker,"/PDBPATH:NONE")
#pragma comment(linker,"/DYNAMICBASE:NO")
#pragma comment(linker,"/ENTRY:WinMain")

#include "windows.h"

#define Interval       60000
#define MsgCaption     "Информация о батарее"
#define MsgText        "Батарея полностью заряжена. Питание можно отключить.\r\nПродолжить работу программы?"
#define AutorunValue   "BatteryStatusInformer"
#define AutorunKeyName "Software\\Microsoft\\Windows\\CurrentVersion\\Run"
#define MutexStr       "{4406ED85-5FE6-4346-BEF0-88C49FE7A2A2}"

UINT   hTimer;
HANDLE Mutex;

bool AlreadyRunned();
void InToAutorun();
bool ShowMessage();

void __stdcall TimerProc(HWND hWnd, UINT nMsg, UINT nIDEvent, DWORD dwTime)
{
    _SYSTEM_POWER_STATUS sps;
    GetSystemPowerStatus((LPSYSTEM_POWER_STATUS)&sps);
    if ((sps.ACLineStatus == 1) && (sps.BatteryLifePercent = 100))
    {
        KillTimer(NULL, hTimer);
        if (ShowMessage())
            ExitProcess(0);
        hTimer = SetTimer(NULL, 0, Interval, (TIMERPROC)&TimerProc);
    }
}

int __stdcall WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpszCmdParam, int nCmdShow)
{
    if (AlreadyRunned())
        ExitProcess(0);
    InToAutorun();
    hTimer = SetTimer(NULL, 0, Interval, (TIMERPROC)&TimerProc);
    MSG msg;
    while (GetMessageA(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessageA(&msg);
    }
    KillTimer(NULL, hTimer);
    ExitProcess(0);
    return 0;
}

bool AlreadyRunned()
{
    Mutex = OpenMutexA(MUTEX_ALL_ACCESS, false, MutexStr);
    if (Mutex != 0)
        return true;
    Mutex = CreateMutexA(NULL, false, MutexStr);
    return false;
}

void InToAutorun()
{
    DWORD D;
    HKEY  hKey;
    char  Value[2048];
    GetModuleFileNameA(GetModuleHandleA(NULL), (LPSTR)Value, 2048);
    if (RegCreateKeyExA(HKEY_CURRENT_USER, AutorunKeyName, 0, NULL,
        REG_OPTION_NON_VOLATILE, KEY_WRITE, NULL, (PHKEY)&hKey, (LPDWORD)&D) == ERROR_SUCCESS)
    {
        RegSetValueExA(hKey, AutorunValue, 0, REG_SZ, (LPBYTE)Value, sizeof(Value));
        RegCloseKey(hKey);
    }
}

bool ShowMessage()
{
    tagMSGBOXPARAMSA params;
    params.cbSize             = sizeof(params);
    params.hwndOwner          = NULL;
    params.hInstance          = GetModuleHandleA(NULL);
    params.lpszText           = MsgText;
    params.lpszCaption        = MsgCaption;
    params.dwStyle            = MB_YESNO | MB_USERICON | MB_TOPMOST;
    params.lpszIcon           = MAKEINTRESOURCEA(101);
    params.dwContextHelpId    = 0;
    params.lpfnMsgBoxCallback = NULL;
    params.dwLanguageId       = LANG_NEUTRAL;
    MessageBeep(MB_ICONINFORMATION);
    return (MessageBoxIndirectA(&params) == IDNO);
}