#include <windows.h>
#include <tchar.h>
#include <cmath> // sin()
#include <cstdlib> // rand(), srand()
#include <ctime> // time()
#include "resource.h" // menu
// OpenGL
#include <gl\GL.h>
#include <gl\GLU.h>
#pragma comment (lib,"opengl32.lib")
#pragma comment (lib,"glu32.lib")

// НОХЯЮМХЕ НАПЮАНРВХЙЮ
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

// global variables
#define PI 3.14159265358979323846
HWND hWnd;
HDC hDC;
HGLRC hRC;
int index = 0;
float mouse_x, mouse_y;
int winWidth = 800, winHeight = 500; // ДКХМЮ, БШЯНРЮ

void InitPixel(HDC hDC)
{
	int PixelFormat;
	PIXELFORMATDESCRIPTOR pfd;
	memset(&pfd,0,sizeof(PIXELFORMATDESCRIPTOR));
	pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
	PixelFormat = ChoosePixelFormat(hDC, &pfd);
	SetPixelFormat(hDC, PixelFormat, &pfd);
}

int random(int min, int max) // [min, max]
{
	//srand((unsigned) time(NULL));
	return rand() % (max - min + 1) + min;
}

void DRAW_sin()
{
	int p = 4;
	float h = 0.01;
	int k = p * 2 * PI / h;
	glPointSize(2);
	glColor3f(0.5, 0.5, 0.5);
	glBegin(GL_POINTS);
	for (int i = 0; i < k; i++) {
		float x = i * h / p / PI - 1;
		float y = sin(i * h) * 0.5;
		glVertex2f(x, y);
	}
	glEnd();
}

void DRAW_tringle()
{
	glBegin(GL_TRIANGLE_STRIP);
	glVertex2f(0, 0);
	for (int i = 0; i < 19; i++)
	{
		float x = (float) rand() / (RAND_MAX + 1) * (winWidth - 0) + 0 + 0.5;
		float y = (float) rand() / (RAND_MAX + 1) * (winHeight - 0) + 0 + 0.5;

		x = (x - ((float) winWidth / 2)) / ((float) winWidth / 2);
		y = (((float) winHeight / 2) - y) / ((float) winHeight / 2);

		glColor3f((float) rand() / RAND_MAX, (float) rand() / RAND_MAX, (float) rand() / RAND_MAX);
		glVertex2f(x, y);
	}
	glEnd();
}

void DRAW_fire()
{
	glEnable(GL_LINE_STIPPLE);

	int k = random(20, 200);

	for (int i = 0; i < k; i++)
	{
		glLineWidth(random(1, 5));
		glLineStipple(random(1, 4), random(0x0000, 0xFFFF));
		glBegin(GL_LINES);

		float x = (mouse_x - ((float) winWidth / 2)) / ((float) winWidth / 2);
		float y = (((float) winHeight / 2) - mouse_y) / ((float) winHeight / 2);
		float x1 = x, y1 = y;

		glColor3f((float) rand() / RAND_MAX, (float) rand() / RAND_MAX, (float) rand() / RAND_MAX);
		glVertex2f(x, y); // mouse pos.

		//x = (float) rand() / (RAND_MAX + 1) * (winWidth - 0) + 0 + 0.5;
		//y = (float) rand() / (RAND_MAX + 1) * (winHeight - 0) + 0 + 0.5;
		x = random(0, winWidth);
		y = random(0, winHeight);
		x = (x - ((float) winWidth / 2)) / ((float) winWidth / 2);
		y = (((float) winHeight / 2) - y) / ((float) winHeight / 2);

		x = x1 + 0.5 * (x * sin(random(0, 360)));
		y = y1 + 0.8 * (y * cos(random(0, 360)));



		glColor3f((float) rand() / RAND_MAX, (float) rand() / RAND_MAX, (float) rand() / RAND_MAX);
		glVertex2f(x, y);

		glEnd();
	}
	glDisable(GL_LINE_STIPPLE);
}

void DRAW()
{
	glClear(GL_COLOR_BUFFER_BIT);
	glClear(GL_DEPTH_BUFFER_BIT);
	if (index == 0)
		DRAW_sin();
	else if (index == 1)
		DRAW_tringle();
	else if (index == 2)
		DRAW_fire();
	SwapBuffers(hDC);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
	// хМХЖХЮКХГЮЖХЪ НЙМЮ
	WNDCLASSEX win;
	win.cbSize         = sizeof(WNDCLASSEX);
    win.style          = CS_HREDRAW | CS_VREDRAW;
    win.lpfnWndProc    = WndProc;
    win.cbClsExtra     = 0;
    win.cbWndExtra     = 0;
    win.hInstance      = hInstance;
    win.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
    win.hCursor        = LoadCursor(NULL, IDC_ARROW);
    win.hbrBackground  = (HBRUSH)(COLOR_WINDOW + 1);
    win.lpszMenuName   = MAKEINTRESOURCE(IDR_MENU1);
    win.lpszClassName  = "MyClassName";
    win.hIconSm        = LoadIcon(win.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

	// пЕЦХЯРПЮЖХЪ НЙМЮ
    if (!RegisterClassEx(&win))
    {
        MessageBox(NULL, "нЬХАЙЮ ПЕЦХЯРПЮЖХХ!", "нЬХАЙЮ", NULL);
        return 1;
    }

	// яНГДЮМХЕ НЙМЮ
    hWnd = CreateWindow(
        "MyClassName",
        "MyTitle",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, // ОНГХЖХЪ НЙМЮ: x, y
        winWidth, winHeight, // ПЮГЛЕПШ НЙМЮ: ЬХПХМЮ, БШЯНРЮ
        NULL,
        NULL,
        hInstance,
		NULL
    );

    if (!hWnd)
    {
        MessageBox(NULL, "нЬХАЙЮ ОПХ ЯНГДЮМХХ НЙМЮ!", "нЬХАЙЮ", NULL);
        return 1;
    }

    ShowWindow(hWnd, nCmdShow);
    UpdateWindow(hWnd);

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

    return 0;
}

// НАПЮАНРВХЙ
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
	case WM_CREATE:
		hDC = GetDC(hWnd);
		hRC = wglCreateContext(hDC);
		InitPixel(hDC);
		hRC = wglCreateContext(hDC);
		wglMakeCurrent(hDC,hRC);
		glClearColor(0.1, 0.1, 0.1, 1.0);
		break;
	//case WM_PAINT:
	//	glViewport(0, 0, winWidth, winHeight);
	//	glClear(GL_COLOR_BUFFER_BIT);
	//	glClear(GL_DEPTH_BUFFER_BIT);
	//	DRAW();
	//	SwapBuffers(hDC);
	//	break;
	case WM_KEYDOWN:
		if (wParam == VK_ESCAPE)
			DestroyWindow(hWnd);
		break;
	case WM_MOUSEMOVE:
		DRAW();
		mouse_x = LOWORD(lParam);
		mouse_y = HIWORD(lParam);
		break;
	case WM_COMMAND:
		switch (LOWORD(wParam))
		{
		case ID_SIN:
			index = 0;
			DRAW();
			break;
		case ID_TRINGLE:
			index = 1;
			DRAW();
			break;
		case ID_FIRE:
			index = 2;
			DRAW();
			break;
		}
		break;
	case WM_SIZE:
        winWidth = LOWORD(lParam);
        winHeight = HIWORD(lParam);
		glViewport(0, 0, winWidth, winHeight);
		DRAW();
        break;
	case WM_DESTROY:
        PostQuitMessage(0);
		wglMakeCurrent(0, 0);
		wglDeleteContext(hRC);
		ReleaseDC(hWnd, hDC);
		DeleteDC(hDC);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
        break;
    }

    return 0;
}