compressdemoview.cpp

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// CompressDemoView.cpp : implementation of the CCompressDemoView class
//

#include "stdafx.h"
#include "CompressDemo.h"

#include "CompressDemoDoc.h"
#include "CompressDemoView.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CCompressDemoView

IMPLEMENT_DYNCREATE(CCompressDemoView, CView)

BEGIN_MESSAGE_MAP(CCompressDemoView, CView)
	//{{AFX_MSG_MAP(CCompressDemoView)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CCompressDemoView construction/destruction

CCompressDemoView::CCompressDemoView()
{

	m_bLoaded = FALSE;

}

CCompressDemoView::~CCompressDemoView()
{
}

BOOL CCompressDemoView::PreCreateWindow(CREATESTRUCT& cs)
{
	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CCompressDemoView drawing

static char *szComps[] = {
"No Compression            ",
"Huffman Compression       ",
"LZSS Compression          ",
"LZW Compression           "
};

void CCompressDemoView::OnDraw(CDC* pDC)
{
	CCompressDemoDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);

	if( !m_bLoaded ){
		CString PathName = pDoc->GetPathName();
		strcpy( m_szFilename, PathName.GetBuffer( 3 ) );
		strcpy( m_szSaveLoad, "File loaded unsuccessfully     " );
		m_pFile = CCompressedFile::MakeNewFile( m_szFilename );
		if( !m_pFile ) AfxMessageBox( "Could not create File class!" );
		else{
			m_dwUncompressedSize = m_dwCompressedSize = 0L;
			if( m_pFile != NULL ){
				if( m_pFile->Open( m_szFilename, CFile::modeRead ) ){
				strcpy( m_szCompression, szComps[m_pFile->m_nCompressionType+1] );
				hGlobal = ::GlobalAlloc( GMEM_FIXED, m_pFile->m_dwUncompressedSize + 100L );
				if( hGlobal ){
					m_cbDataBuffer = (unsigned char *) ::GlobalLock( hGlobal );
					BeginWaitCursor();
					m_pFile->Read( m_cbDataBuffer, m_pFile->m_dwUncompressedSize );
					EndWaitCursor();
					m_bSuccess = TRUE;
					m_dwUncompressedSize = m_pFile->m_dwUncompressedSize;
					m_dwCompressedSize = m_pFile->m_dwCompressedSize;
					strcpy( m_szSaveLoad, "File loaded successfully     " );
					}
				else AfxMessageBox( "Couldn't create!" );
				m_pFile->Close();
				}
			else AfxMessageBox( "Couldn't open file!" );
			delete m_pFile;
			m_pFile = NULL;
			}
		}
		m_bLoaded = TRUE;
		}

	char junk[200];
	wsprintf( junk, "File:%s          ", m_szFilename );
	pDC->TextOut( 10, 10, junk, strlen( junk ) );
	wsprintf( junk, "Uncompressed Size:%ld, Compressed Size:%ld, Ratio:%ld%%          ", m_dwUncompressedSize, m_dwCompressedSize, ( m_dwCompressedSize * 100 ) / m_dwUncompressedSize );
	pDC->TextOut( 10, 30, junk, strlen( junk ) );
	pDC->TextOut( 10, 50, m_szSaveLoad, strlen( m_szSaveLoad ) );
	pDC->TextOut( 10, 70, m_szCompression, strlen( m_szCompression ) );

}

/////////////////////////////////////////////////////////////////////////////
// CCompressDemoView diagnostics

#ifdef _DEBUG
void CCompressDemoView::AssertValid() const
{
	CView::AssertValid();
}

void CCompressDemoView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}

CCompressDemoDoc* CCompressDemoView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CCompressDemoDoc)));
	return (CCompressDemoDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CCompressDemoView message handlers

void CCompressDemoView::OnFileSaveAs( const char *Filename ) 
{
	CCompressDemoDoc *pDoc = GetDocument();

	if( !hGlobal ){
		AfxMessageBox( "No buffer to save!" );
		return;
		}
  
	if( !m_dwUncompressedSize ){
		AfxMessageBox( "The size of the data is zero!" );
		return;
		}

	m_pFile = CCompressedFile::MakeNewFile( NULL, pDoc->m_nCompressionSelected );
	if( !m_pFile ) AfxMessageBox( "Couldn't create!" );
	else{
		strcpy( m_szSaveLoad, "File saved unsuccessfully     " );
		if( !m_pFile->Open( Filename, CFile::modeWrite | CFile::modeCreate ) ) AfxMessageBox( "Couldn't create!" );
		else{
			BeginWaitCursor();
			m_pFile->Write( m_cbDataBuffer, m_dwUncompressedSize );
			m_pFile->Close();
			EndWaitCursor(); 
			m_dwCompressedSize = m_pFile->m_dwCompressedSize;
			strcpy( m_szFilename, Filename );
			strcpy( m_szSaveLoad, "File saved successfully     " );
			strcpy( m_szCompression, szComps[m_pFile->m_nCompressionType+1] );
			InvalidateRect( NULL );
			UpdateWindow();
			}
		delete m_pFile;
		m_pFile = NULL;
		}

}