#include "pch.h"
#include "CImageStatic.h"

IMPLEMENT_DYNAMIC(CImageStatic, CStatic)

CImageStatic::CImageStatic()
{

}

CImageStatic::~CImageStatic()
{

}

BEGIN_MESSAGE_MAP(CImageStatic, CStatic)
END_MESSAGE_MAP()

BOOL CImageStatic::SetImage(LPCTSTR szImage)
{
	CString szPath = Utils::GetExecDir();
	szPath.Append(_T("\\"));
	szPath.Append(szImage);

	BOOL bRet = FALSE;
	m_Image.Destroy();
	bRet = (m_Image.Load(szPath) == S_OK);
	if (m_hWnd)
	{
		Invalidate(FALSE);
	}

	return bRet;
}

LRESULT CImageStatic::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)
{
	switch (message)
	{
		case(WM_ERASEBKGND):
			return 1;
		case(WM_PAINT):
		{
			PAINTSTRUCT ps;
			CDC *pDstDC = BeginPaint(&ps);

			//客户区位置
			CRect rcClient;
			GetClientRect(&rcClient);

			//双缓冲绘图
			{
				CMemDC memDC(*pDstDC, rcClient);
				CDC *pDC = &memDC.GetDC();

				//填充背景色
				pDC->FillSolidRect(&rcClient, RGB(100, 100, 100));
				pDC->SetStretchBltMode(HALFTONE);

				if (!m_Image.IsNull())
				{
					//原图大小
					CRect rcSrc(0, 0, m_Image.GetWidth(), m_Image.GetHeight());
					//锁定原图比例
					double fZoomRate = min((double)rcClient.Width() / (double)rcSrc.Width(),
						(double)rcClient.Height() / (double)rcSrc.Height());
					int cx = (int)(rcSrc.Width()*fZoomRate), cy = (int)(rcSrc.Height()*fZoomRate);
					CRect rcDst(0, 0, cx, cy); //目标大小
					rcDst.OffsetRect((rcClient.Width() - cx) / 2, (rcClient.Height() - cy) / 2);//居中

					//绘图
					m_Image.Draw(pDC->m_hDC, rcDst, rcSrc);
				}
			}

			EndPaint(&ps);
			return 0;
		}
	}
	return CStatic::WindowProc(message, wParam, lParam);
}