/* 17 july 2014 */

#include "winapi_windows.h"
#include "_cgo_export.h"

#define windowclass L"gouiwindow"

static LRESULT CALLBACK windowWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	void *data;
	RECT r;

	data = (void *) GetWindowLongPtrW(hwnd, GWLP_USERDATA);
	if (data == NULL) {
		/* the lpParam is available during WM_NCCREATE and WM_CREATE */
		if (uMsg == WM_NCCREATE) {
			storelpParam(hwnd, lParam);
			data = (void *) GetWindowLongPtrW(hwnd, GWLP_USERDATA);
			storeWindowHWND(data, hwnd);
		}
		/* act as if we're not ready yet, even during WM_NCCREATE (nothing important to the switch statement below happens here anyway) */
		return DefWindowProcW(hwnd, uMsg, wParam, lParam);
	}

	switch (uMsg) {
	case WM_COMMAND:
		return forwardCommand(hwnd, uMsg, wParam, lParam);
	case WM_SIZE:
		if (GetClientRect(hwnd, &r) == 0)
			xpanic("error getting client rect for Window in WM_SIZE", GetLastError());
		windowResize(data, &r);
		return 0;
	case WM_CLOSE:
		windowClosing(data);
		return 0;
	default:
		return DefWindowProcW(hwnd, uMsg, wParam, lParam);
	}
	xmissedmsg("Window", "windowWinProc()", uMsg);
	return 0;		/* unreached */
}

DWORD makeWindowWindowClass(char **errmsg)
{
	WNDCLASSW wc;

	ZeroMemory(&wc, sizeof (WNDCLASSW));
	wc.lpfnWndProc = windowWndProc;
	wc.hInstance = hInstance;
	wc.hIcon = hDefaultIcon;
	wc.hCursor = hArrowCursor;
	wc.hbrBackground = (HBRUSH) (COLOR_BTNFACE + 1);
	wc.lpszClassName = windowclass;
	if (RegisterClassW(&wc) == 0) {
		*errmsg = "error registering Window window class";
		return GetLastError();
	}
	return 0;
}

HWND newWindow(LPCWSTR title, int width, int height, void *data)
{
	HWND hwnd;

	hwnd = CreateWindowExW(
		0,
		windowclass, title,
		WS_OVERLAPPEDWINDOW,
		CW_USEDEFAULT, CW_USEDEFAULT,
		width, height,
		NULL, NULL, hInstance, data);
	if (hwnd == NULL)
		xpanic("Window creation failed", GetLastError());
	return hwnd;
}

void windowClose(HWND hwnd)
{
	if (DestroyWindow(hwnd) == 0)
		xpanic("error destroying window", GetLastError());
}