5sPP2Task5

#include <windows.h>
#include <time.h>
#include <stdio.h>
#include <string>

using namespace std;

HWND edt;
HDC dc;

LRESULT WndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
{
    if (message == WM_DESTROY)
        PostQuitMessage(0);
    else if (message == WM_COMMAND)
    {
        if (LOWORD(wparam) == 1) {
            SetDCBrushColor(dc, RGB(255, 255, 255));
            SetDCPenColor(dc, RGB(255, 255, 255));

            Rectangle(dc, 0, 0, 400, 400);

            int textLength = GetWindowTextLength(edt);
            string txt(textLength, '\0');
            GetWindowTextA(edt, &txt[0], textLength + 1);

            SetDCBrushColor(dc, RGB(230, 230, 230));
            SetDCPenColor(dc, RGB(0, 0, 0));

            for (int i = 0; i < stoi(txt); i++) {
                int r = 1 + rand() % 50;
                int x1 = 1 + rand() % 300;
                int y1 = 1 + rand() % 300;
                int x2 = x1 + 2 * r;
                int y2 = y1 + 2 * r;
                Ellipse(dc, x1, y1, x2, y2);
            }
        }
    }
    else return DefWindowProcA(hwnd, message, wparam, lparam);
}

int main()
{
    srand(time(NULL));

    WNDCLASSA wcl;
    memset(&wcl, 0, sizeof(WNDCLASSA));
    wcl.lpszClassName = "my_Window";
    wcl.lpfnWndProc = WndProc;
    RegisterClassA(&wcl);
    HWND hwnd = CreateWindow(L"my_Window", L"Окошечко", WS_OVERLAPPEDWINDOW, 10, 10, 640, 480, NULL, NULL, NULL, NULL);

    MSG msg;
    ShowWindow(hwnd, SW_SHOWNORMAL);

    dc = GetDC(hwnd);
    SelectObject(dc, GetStockObject(DC_BRUSH));
    SelectObject(dc, GetStockObject(DC_PEN));

    HWND lbl = CreateWindow(L"static", L"Number: ", WS_VISIBLE | WS_CHILD, 440, 10, 65, 25, hwnd, NULL, NULL, NULL);
    edt = CreateWindow(L"edit", L"30", WS_VISIBLE | WS_CHILD | WS_BORDER | ES_RIGHT, 515, 10, 45, 20, hwnd, NULL, NULL, NULL);
    HWND btn = CreateWindow(L"button", L"Ok", WS_VISIBLE | WS_CHILD, 570, 10, 50, 20, hwnd, (HMENU)1, NULL, NULL);

    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return 0;
}