#include <windows.h>
#include <assert.h>
#include "ttwain_win.h"
#include "ttwain_winPD.h"
#include "ttwain_state.h"
#include "ttwain_error.h"

#define HINSTLIB0 0
static HWND Dummy = 0; /* proxy window */

extern int TTWAIN_MessageHook(void *lpmsg);

static HWND CreateDummyWindow(void)
{
	HWND hwnd;
	hwnd = CreateWindow("STATIC",					  // class
						"Acquire Dummy",			  // title
						WS_POPUPWINDOW,				  // style
						CW_USEDEFAULT, CW_USEDEFAULT, // x, y
						CW_USEDEFAULT, CW_USEDEFAULT, // width, height
						HWND_DESKTOP,				  // parent window
						NULL,						  // hmenu
						HINSTLIB0,					  // hinst
						NULL);						  // lpvparam
	return hwnd;
}
/*---------------------------------------------------------------------------*/
void *TTWAIN_GetValidHwndPD(void *_hwnd)
// Returns a valid window handle as follows:
// If hwnd is a valid window handle, hwnd is returned.
// Otherwise a proxy window handle is created and returned.
// Once created, a proxy window handle is destroyed when
// the source manager is unloaded.
// If hwnd is an invalid window handle (other than NULL)
// an error box is displayed.
{
	HWND hwnd = (HWND)_hwnd;
	if (!IsWindow(hwnd)) {
		if (hwnd != NULL) {
			assert(!"Window handle is invalid");
			hwnd = NULL;
		}
		if (!Dummy) {
			Dummy = CreateDummyWindow();
			if (!IsWindow(Dummy)) {
				assert(!"Unable to create Dummy window");
				Dummy = NULL;
			}
		}
		hwnd = Dummy;
	}
	return (void *)hwnd;
}
/*---------------------------------------------------------------------------*/
void TTWAIN_EmptyMessageQueuePD(void)
{
	MSG msg;
#ifdef _DEBUG
	OutputDebugString("EmptyMsgQ<");
#endif
	while (PeekMessage((LPMSG)&msg, NULL, 0, 0, PM_REMOVE)) {
		if (!TTWAIN_MessageHook((LPMSG)&msg)) {
			TranslateMessage((LPMSG)&msg);
			DispatchMessage((LPMSG)&msg);
#ifdef _DEBUG
			OutputDebugString("-");
#endif
		} else {
#ifdef _DEBUG
			OutputDebugString("T");
#endif
		}
	}
#ifdef _DEBUG
	OutputDebugString(">\n");
#endif
}

void TTWAIN_ModalEventLoopPD(void)
{
	MSG msg;
	// Clear global breakout flag
	TTwainData.breakModalLoop = FALSE;

	while ((TTWAIN_GetState() >= TWAIN_SOURCE_ENABLED) && !TTwainData.breakModalLoop && GetMessage((LPMSG)&msg, NULL, 0, 0)) {
		if (!TTWAIN_MessageHook((LPMSG)&msg)) {
			TranslateMessage((LPMSG)&msg);
			DispatchMessage((LPMSG)&msg);
		}
	} // while
	TTwainData.breakModalLoop = FALSE;
}
int TTWAIN_EnableWindowPD(void *hwnd, int flag)
{
	return EnableWindow(hwnd, flag);
}