// dlgfileDlg.cpp : implementation file
//

#include "stdafx.h"
#include "dlgfile.h"
#include "dlgfileDlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About

class CAboutDlg : public CDialog
{
public:
	CAboutDlg();

// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA

	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL

// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};

CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
	//{{AFX_DATA_INIT(CAboutDlg)
	//}}AFX_DATA_INIT
}

void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CAboutDlg)
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CDlgfileDlg dialog

CDlgfileDlg::CDlgfileDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CDlgfileDlg::IDD, pParent)
{

	//{{AFX_DATA_INIT(CDlgfileDlg)
	m_strFilePath = _T("");
	m_strPassWord = _T("");
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CDlgfileDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CDlgfileDlg)
	DDX_Control(pDX, IDC_FILE_PATHWORD, m_CtrlPWD);
	DDX_Text(pDX, IDC_FLIE_PATH, m_strFilePath);
	DDX_Text(pDX, IDC_FILE_PATHWORD, m_strPassWord);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CDlgfileDlg, CDialog)
	//{{AFX_MSG_MAP(CDlgfileDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_SELECT_FILE, OnSelectFile)
	ON_BN_CLICKED(IDC_ECFILE, OnEcfile)
	ON_BN_CLICKED(IDC_DCFILE, OnDcfile)
	ON_BN_CLICKED(IDC_EXIT, OnExit)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CDlgfileDlg message handlers

BOOL CDlgfileDlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	
	// TODO: Add extra initialization here
	m_bCheck = FALSE;	//文件沒加密

	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CDlgfileDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}

// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.

void CDlgfileDlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CDlgfileDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

void CDlgfileDlg::OnSelectFile() 
{
	// TODO: Add your control notification handler code here
	CFileDialog dlg(true);
	if(dlg.DoModal() == IDOK)
	{
		m_strFilePath = dlg.GetPathName();		//其中m_strFilePath為CString型
		UpdateData(FALSE);
	}
	m_bCheck = BEcfile((LPCTSTR) m_strFilePath);
	GetDlgItem(IDC_ECFILE)->EnableWindow(!m_bCheck);	
}

_int64 CDlgfileDlg::epass()
{
	DWORD plen;
	char *ppass;
	__int64 mc= 8757735233305;
	UpdateData(TRUE);

	ppass = m_strPassWord.GetBuffer(0);

	plen = strlen(ppass);

	for(int i=0; i<(int)plen; i++)
	{
		mc ^= ppass[i]|128;
	}
	return mc;

}

BOOL CDlgfileDlg::ecfile(LPCTSTR fpath)
{
	char *data;
	CFile *file;
	DWORD flen;

	_int64 m_password = epass();//密碼初始化

	file = new CFile;
	if ( !file->Open(fpath, CFile::shareDenyNone|CFile::modeReadWrite))
	{
		return FALSE;
	}

	flen = file->GetLength();
	data = new char[(int)flen];//為文件分配內存

	file->SeekToBegin();
	file->Read(data, flen);

        //這里把文件的所有字節都進行加密了
	for(int i=0; i<(int)flen; i++)
	{
		data[i] ^= m_password;
		data[i] ^= flen;                //因為每次加密后文件的大小都會增加5字節,所以如果兩次用同一密碼進行加密也沒關系
	}

	file->SeekToBegin();
	file->Write(data, flen);
	delete[] data;                          //先釋放內存

	//添加密碼驗證信息
	char cpass[5] = "love";
	for(int j=0; j<5; j++)
	{
		cpass[j] ^= m_password;
	}
	file->SeekToEnd();
	file->Write(&cpass, 5);        //在文件尾添加密碼嚴整部分,,這樣文件就會增加5字節

	char cExtern = 'a';  //在文件最后加上1個a,用于判斷該文件是否已經加密
	file->SeekToEnd();
	file->Write(&cExtern, 1); 

	file->Close();
	delete file;

	m_bCheck = TRUE;

	return TRUE;
}

BOOL CDlgfileDlg::dcfile(LPCTSTR fpath)
{
	char *data;
	CFile *file;
	DWORD flen;
	char love[5];

	file = new CFile;
	if( !file->Open(fpath, CFile::shareDenyNone|CFile::modeReadWrite))
	{
		return FALSE;
	}

	flen = file->GetLength();
	file->SetLength(flen - 1);

	flen = file->GetLength();
	data = new char[(int)flen];
	//檢驗密碼是不是正確
	file->Seek(-5, CFile::end);
	file->Read(&love, 5);

	_int64 m_password = epass();

	for(int i=0; i<5; i++)
	{
              love[i] ^= m_password;
	}

	if(strcmp(love, "love")!=0)
	{
		MessageBox("the wrong password!");
		return FALSE;
	}

	//解密
	file->SeekToBegin();
	file->Read(data, flen);

        //按照原來的方法進行解密
	for(int j=0; j<(int)flen; j++)
	{
		data[j] ^= m_password;
		data[j] ^= (flen-5);
	}
	file->SeekToBegin();
	file->Write(data, flen);
	file->SetLength(flen-5);     //刪除加密是添加的密碼驗證部分
	file->Close();

	delete[] data;
	delete file;

	m_bCheck = TRUE;

	return TRUE;

}

void CDlgfileDlg::OnEcfile() 
{
	// TODO: Add your control notification handler code here

	ecfile((LPCTSTR)m_strFilePath);
	GetDlgItem(IDC_ECFILE)->EnableWindow(!m_bCheck);
	m_CtrlPWD.SetWindowText("");
}

void CDlgfileDlg::OnDcfile() 
{
	// TODO: Add your control notification handler code here

	dcfile((LPCTSTR)m_strFilePath);
	GetDlgItem(IDC_ECFILE)->EnableWindow(TRUE);	
	m_CtrlPWD.SetWindowText("");
}

void CDlgfileDlg::OnExit() 
{
	// TODO: Add your control notification handler code here
	CDialog::OnOK();
}

BOOL CDlgfileDlg::BEcfile(LPCTSTR sfilepath)
{
	char cExtern;
	char d = 'a';
	CFile f;
	f.Open( (LPCTSTR)m_strFilePath, CFile::shareDenyNone|CFile::modeReadWrite );
	f.Seek(-1, CFile::end);
	f.Read(&cExtern, 1);

	if( cExtern == 'a' )
	{
		return TRUE;
	}
	else
	{
		return FALSE;
	}

}