/*
 *  ReactOS Task Manager
 *
 *  proclist.c
 *
 *  Copyright (C) 1999 - 2001  Brian Palmer  <brianp@reactos.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
	
#define WIN32_LEAN_AND_MEAN	/* Exclude rarely-used stuff from Windows headers */
#include <windows.h>
#include <commctrl.h>
#include <stdlib.h>
#include <malloc.h>
#include <memory.h>
#include <tchar.h>
#include <stdio.h>
#include <winnt.h>
	
#include "taskmgr.h"
#include "procpage.h"
#include "proclist.h"
#include "perfdata.h"


LRESULT CALLBACK	ProcessListWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);

LONG				OldProcessListWndProc;


LRESULT CALLBACK ProcessListWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	HBRUSH	hbrBackground;
	RECT	rcItem;
	RECT	rcClip;
	HDC		hDC;
	int		DcSave;

	switch (message)
	{
	case WM_ERASEBKGND:

		/*
		 * The list control produces a nasty flicker
		 * when the user is resizing the window because
		 * it erases the background to white, then
		 * paints the list items over it.
		 *
		 * We will clip the drawing so that it only
		 * erases the parts of the list control that
		 * show only the background.
		 */

		/*
		 * Get the device context and save it's state
		 * to be restored after we're done
		 */
		hDC = (HDC) wParam;
		DcSave = SaveDC(hDC);

		/*
		 * Get the background brush
		 */
		hbrBackground = (HBRUSH) GetClassLong(hWnd, GCL_HBRBACKGROUND);

		/*
		 * Calculate the clip rect by getting the RECT
		 * of the first and last items and adding them up.
		 *
		 * We also have to get the item's icon RECT and
		 * subtract it from our clip rect because we don't
		 * use icons in this list control.
		 */
		ListView_GetItemRect(hWnd, 0, &rcClip, LVIR_BOUNDS);
		ListView_GetItemRect(hWnd, ListView_GetItemCount(hWnd) - 1, &rcItem, LVIR_BOUNDS);
		rcClip.bottom = rcItem.bottom;
		ListView_GetItemRect(hWnd, 0, &rcItem, LVIR_ICON);
		rcClip.left = rcItem.right;

		/*
		 * Now exclude the clip rect
		 */
		ExcludeClipRect(hDC, rcClip.left, rcClip.top, rcClip.right, rcClip.bottom);

		/*
		 * Now erase the background
		 *
		 *
		 * FIXME: Should I erase it myself or
		 * pass down the updated HDC and let
		 * the default handler do it?
		 */
		GetClientRect(hWnd, &rcItem);
		FillRect(hDC, &rcItem, hbrBackground);

		/*
		 * Now restore the DC state that we
		 * saved earlier
		 */
		RestoreDC(hDC, DcSave);
		
		return TRUE;
	}

	/*
	 * We pass on all messages except WM_ERASEBKGND
	 */
	return CallWindowProc((WNDPROC)OldProcessListWndProc, hWnd, message, wParam, lParam);
}