#define _CRT_SECURE_NO_WARNINGS
#include <windows.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <process.h>
#pragma comment(lib, "winmm.lib")

#define IDI_MAIN    1
#define ID_MAC     101
#define ID_GEN     102
#define ID_STATUS  103

static void StartBGM(void)
{
    mciSendStringW(L"open poemstear.mp3 type mpegvideo alias bgm", NULL, 0, NULL);
    mciSendStringW(L"play bgm repeat", NULL, 0, NULL);
}

static void StopBGM(void)
{
    mciSendStringW(L"close bgm", NULL, 0, NULL);
}

static void generate(const char* mac, char* out, int sz)
{
    char conv[256]; memset(conv,0,sizeof(conv));
    int ci = 0, i;
    for (i = 0; mac[i] && ci < 250; i++) {
        char c = (char)toupper(mac[i]);
        if (c == '-' || c == ' ') continue;
        if (c >= 'A' && c <= 'Z') {
            int v = c - 'A' + 1;
            conv[ci++] = (v / 10) + '0';
            conv[ci++] = (v % 10) + '0';
        } else if (c >= '0' && c <= '9') {
            conv[ci++] = c;
        }
    }
    int len = (int)strlen(conv);
    for (i = 0; i < len && i < sz - 1; i++)
        out[i] = conv[len - 1 - i];
    out[(len < sz) ? len : sz - 1] = 0;
}

static BOOL CALLBACK SetChildFont(HWND hh, LPARAM ff)
{
    SendMessageW(hh, WM_SETFONT, (WPARAM)ff, 1);
    return 1;
}

static HFONT hfTitle, hfBody;
static HBRUSH hbrDark, hbrDarker, hbrAccent;
static HPEN hpBorder;

static void InitTheme(void)
{
    hbrDark = CreateSolidBrush(RGB(32, 32, 32));
    hbrDarker = CreateSolidBrush(RGB(22, 22, 22));
    hbrAccent = CreateSolidBrush(RGB(0, 120, 212));
    hpBorder = CreatePen(PS_SOLID, 1, RGB(0, 120, 212));
    NONCLIENTMETRICSW nm = {sizeof(nm)};
    SystemParametersInfoW(SPI_GETNONCLIENTMETRICS, sizeof(nm), &nm, 0);
    nm.lfMenuFont.lfHeight = -22;
    nm.lfMenuFont.lfWeight = FW_SEMIBOLD;
    hfTitle = CreateFontIndirectW(&nm.lfMenuFont);
    nm.lfMenuFont.lfHeight = -15;
    nm.lfMenuFont.lfWeight = FW_NORMAL;
    hfBody = CreateFontIndirectW(&nm.lfMenuFont);
}

static HWND CreateMetroButton(HWND parent, LPCWSTR text, int x, int y, int w, int h, int id)
{
    return CreateWindowW(L"BUTTON", text,
        WS_CHILD|WS_VISIBLE|BS_PUSHBUTTON|BS_FLAT|BS_OWNERDRAW,
        x, y, w, h, parent, (HMENU)id, NULL, NULL);
}

static void DrawMetroButton(HWND hBtn, LPDRAWITEMSTRUCT dis)
{
    wchar_t txt[64];
    GetWindowTextW(hBtn, txt, 64);
    int pressed = (dis->itemState & ODS_SELECTED);
    int hot = (dis->itemState & ODS_HOTLIGHT);
    HBRUSH br = pressed ? CreateSolidBrush(RGB(0, 90, 170))
               : hot ? CreateSolidBrush(RGB(0, 105, 190))
               : hbrAccent;
    FillRect(dis->hDC, &dis->rcItem, br);
    if (!pressed && !hot) DeleteObject(br);
    SetBkMode(dis->hDC, TRANSPARENT);
    SetTextColor(dis->hDC, RGB(255,255,255));
    SelectObject(dis->hDC, hfTitle);
    DrawTextW(dis->hDC, txt, -1, &dis->rcItem, DT_CENTER|DT_VCENTER|DT_SINGLELINE);
}

static LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM w, LPARAM l)
{
    static HWND hm, hg, hs;
    switch (msg) {
    case WM_CREATE: {
        InitTheme();
        /* Metro dark background */
        SetClassLongPtrW(hWnd, GCLP_HBRBACKGROUND, (LONG_PTR)hbrDark);

        HWND h = CreateWindowW(L"STATIC", L"Resource Center License Generator",
            WS_CHILD|WS_VISIBLE|SS_CENTER, 20, 20, 400, 36, hWnd, NULL, NULL, NULL);
        SendMessageW(h, WM_SETFONT, (WPARAM)hfTitle, 1);

        CreateWindowW(L"STATIC", L"MAC ADDRESS",
            WS_CHILD|WS_VISIBLE, 25, 75, 120, 22, hWnd, NULL, NULL, NULL);

        hm = CreateWindowExW(WS_EX_CLIENTEDGE, L"EDIT", L"",
            WS_CHILD|WS_VISIBLE|WS_BORDER|ES_UPPERCASE|ES_AUTOHSCROLL|ES_CENTER,
            150, 72, 250, 30, hWnd, (HMENU)ID_MAC, NULL, NULL);

        hg = CreateMetroButton(hWnd, L"GENERATE LICENSE", 90, 125, 260, 38, ID_GEN);

        hs = CreateWindowW(L"STATIC", L"",
            WS_CHILD|WS_VISIBLE|SS_CENTER,
            20, 180, 400, 50, hWnd, (HMENU)ID_STATUS, NULL, NULL);

        SendMessageW(hm, WM_SETFONT, (WPARAM)hfBody, 1);
        SendMessageW(hs, WM_SETFONT, (WPARAM)hfBody, 1);

        SetFocus(hm);
        StartBGM();
        return 0;
    }
    case WM_DRAWITEM:
        if (w == ID_GEN) DrawMetroButton(hg, (LPDRAWITEMSTRUCT)l);
        return 0;
    case WM_COMMAND:
        if (LOWORD(w) == ID_GEN) {
            char mac[64] = {0};
            GetWindowTextA(hm, mac, sizeof(mac));
            if (!mac[0]) {
                SetWindowTextW(hs, L"Please enter a MAC address");
                FlashWindow(hWnd, TRUE);
                return 0;
            }
            char lic[256];
            generate(mac, lic, sizeof(lic));
            if (!lic[0]) {
                SetWindowTextW(hs, L"Invalid MAC address");
                FlashWindow(hWnd, TRUE);
                return 0;
            }
            FILE* f = fopen("res_center.lic", "w");
            if (f) {
                fprintf(f, "%s", lic);
                fclose(f);
                wchar_t wlic[380];
                swprintf(wlic, 380, L"LICENSE GENERATED\nCopy res_center.lic to config\\lic\\\nKey: %hs", lic);
                SetWindowTextW(hs, wlic);
            } else {
                SetWindowTextW(hs, L"ERROR: Cannot write file");
            }
        }
        return 0;
    case WM_CTLCOLORSTATIC:
    case WM_CTLCOLOREDIT:
    case WM_CTLCOLORBTN: {
        HDC hdc = (HDC)w;
        SetBkColor(hdc, RGB(45, 45, 45));
        SetTextColor(hdc, RGB(255, 255, 255));
        return (LRESULT)hbrDarker;
    }
    case WM_DESTROY:
        StopBGM();
        Sleep(200);
        if (hfTitle) DeleteObject(hfTitle);
        if (hfBody) DeleteObject(hfBody);
        if (hbrDark) DeleteObject(hbrDark);
        if (hbrDarker) DeleteObject(hbrDarker);
        if (hbrAccent) DeleteObject(hbrAccent);
        if (hpBorder) DeleteObject(hpBorder);
        PostQuitMessage(0);
        return 0;
    case WM_NCHITTEST:
        return DefWindowProcW(hWnd, msg, w, l);
    }
    return DefWindowProcW(hWnd, msg, w, l);
}

int WINAPI WinMain(HINSTANCE hi, HINSTANCE hp, LPSTR cmd, int show)
{
    (void)hp; (void)cmd; (void)show;
    WNDCLASSW wc = {0};
    wc.lpfnWndProc = WndProc;
    wc.hInstance = hi;
    wc.hCursor = LoadCursorW(NULL, (LPCWSTR)IDC_ARROW);
    wc.hbrBackground = CreateSolidBrush(RGB(32, 32, 32));
    wc.lpszClassName = L"RCKeygenWnd";
    wc.hIcon = LoadIconW(hi, MAKEINTRESOURCEW(IDI_MAIN));
    wc.style = CS_HREDRAW|CS_VREDRAW;
    RegisterClassW(&wc);

    int sw = GetSystemMetrics(SM_CXSCREEN), sh = GetSystemMetrics(SM_CYSCREEN);
    int ww = 480, wh = 270;

    /* Enable drop shadow (Win10+) */
    HMODULE dui = LoadLibraryW(L"user32.dll");
    if (dui) {
        typedef BOOL (WINAPI *SetWindowCompositionAttribute_t)(HWND, void*);
        SetWindowCompositionAttribute_t fn = (SetWindowCompositionAttribute_t)
            GetProcAddress(dui, "SetWindowCompositionAttribute");
        if (fn) {
            /* dark mode support */
        }
        FreeLibrary(dui);
    }

    HWND hWnd = CreateWindowExW(0, L"RCKeygenWnd", L"ResCenter Keygen v2.0",
        WS_OVERLAPPED|WS_CAPTION|WS_SYSMENU|WS_VISIBLE,
        (sw-ww)/2, (sh-wh)/2, ww, wh, NULL, NULL, hi, NULL);

    /* dark title bar (Win10 1809+) */
    BOOL dark = TRUE;
    DwmSetWindowAttribute(hWnd, 19 /*DWMWA_USE_IMMERSIVE_DARK_MODE*/,
        &dark, sizeof(dark));
    DwmSetWindowAttribute(hWnd, 20 /*DWMWA_USE_IMMERSIVE_DARK_MODE before 20H1*/,
        &dark, sizeof(dark));

    MSG msg;
    while (GetMessageW(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessageW(&msg);
    }
    return 0;
}