#include <iostream>
#include <Windows.h>
#include <time.h>
#include <stdlib.h>
#include <stdio.h>

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
POINT start;

int max = 500, current = 10;
int randx, randy, randz;

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    srand(time(0));

    HWND Main;
    MSG msg;

    WNDCLASSEX wc;

    char szClassName[] = "AppClass";

    wc.style = 0;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hIcon = 0;
    wc.hCursor = 0;
    wc.hbrBackground = 0;
    wc.lpszMenuName = NULL;
    wc.hIconSm = 0;

    wc.cbSize = sizeof(wc);
    wc.lpszClassName = szClassName;
    wc.hInstance = hInstance;
    wc.lpfnWndProc = WndProc;

    if (!RegisterClassEx(&wc)) {
        MessageBox(NULL, "Не удалось зарегистрировать класс окна", "Ошибка", MB_OK);
        return 0;
    }

    Main = CreateWindow(szClassName, "dsg", DS_CENTER | WS_MAXIMIZEBOX | WS_SYSMENU, CW_USEDEFAULT, 0, 500, 500, 0,0, hInstance,0);

    ShowWindow(Main, nCmdShow);

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

    return 1;
}


LRESULT CALLBACK WndProc(HWND hDlg, UINT Msg, WPARAM wParam, LPARAM lParam) {
    PAINTSTRUCT ps;
    RECT rect;
    HDC hdc;

    switch (Msg) {
        case WM_CREATE: {

            break;
        }
        case WM_LBUTTONDOWN: {
            start.x = LOWORD(lParam);
            start.y = HIWORD(lParam);

            hdc = GetDC(hDlg);
            current = 10;

            randx = 0 + rand() % 255,
                randy = 0 + rand() % 255,
                randz = 0 + rand() % 255;

            HBRUSH hPen = CreateSolidBrush(RGB(randx, randy, randz));
            SelectObject(hdc, hPen);

            Ellipse(hdc, start.x - current, start.y - current, start.x + current, start.y + current);

            ReleaseDC(hDlg, hdc);

            SetTimer(hDlg, 100, 100, NULL);
            break;
        }
        case WM_TIMER: {
            current += 10;
            hdc = GetDC(hDlg);

            HBRUSH hPen = CreateSolidBrush(RGB(randx, randy, randz));
            SelectObject(hdc, hPen);

            Ellipse(hdc, start.x - current, start.y - current, start.x + current, start.y + current);

            ReleaseDC(hDlg, hdc);
            if (current >= max) KillTimer(hDlg, 100);
            break;
        }
        case WM_CLOSE: {
            DestroyWindow(hDlg);
            break;
        }
        case WM_DESTROY: {
            PostQuitMessage(0);
            break;
        }
        default: {
            return DefWindowProc(hDlg, Msg, wParam, lParam); //обработка сообщений по умолчанию
        }
    }
    return 1;
}