Mouse Gestures for Internet Explorer

///////////////////////////////////////////////////////////////
//
// HotKeyCtrlEx.cpp
//
// Created: rhare - 21/07/2005
// Copyright (c) 2005 Ralph Hare (ralph.hare@ysgyfarnog.co.uk)
// All rights reserved.
//
// The code and information is provided "as-is" without
// warranty of any kind, either expressed or implied.
//
///////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "HotKeyCtrlEx.h"
#include "tstring.h"
#include <atlmisc.h>

namespace
{
    WORD GetModifier( DWORD vkCode )
    {
        switch( vkCode )
        {
        case VK_LCONTROL:
        case VK_RCONTROL:
            return HOTKEYF_CONTROL;

        case VK_LMENU:
        case VK_RMENU:
            return HOTKEYF_ALT;

        case VK_LSHIFT:
        case VK_RSHIFT:
            return HOTKEYF_SHIFT;
        }

        return 0;
    }

    bool IsFunctionKey( WORD vkCode )
    {
        return ( vkCode >= VK_F1 ) && ( vkCode <= VK_F24 );
    }

    template< typename T, typename U >
    bool CheckFlag( T val, U flag )
    {
        return static_cast< U >( val & flag ) == flag;
    }

    void NotifyParent( HWND hWnd )
    {
        ::SendMessage( 
                ::GetParent( hWnd ), 
                WM_COMMAND,
                MAKELONG( 0x0300, ::GetDlgCtrlID( hWnd ) ),
                NULL
                );
    }

    tstring GetHotKeyText( WORD vkCode, WORD modifiers )
    {
        if( vkCode == 0 )
        {
            return _T( "" );
        }

        tostringstream  os;
        if( CheckFlag( modifiers, HOTKEYF_CONTROL ) )
        {
            os << _T( "Ctrl+" );
        }

        if( CheckFlag( modifiers, HOTKEYF_ALT ) )
        {
            os << _T( "Alt+" );
        }

        if( CheckFlag( modifiers, HOTKEYF_SHIFT ) )
        {
            os << _T( "Shift+" );
        }

        DWORD   keyName = ::MapVirtualKey( vkCode, 0 ) << 16;
        keyName |= ( CheckFlag( modifiers, HOTKEYF_EXT ) ? 0x1000000 : 0 );

        TCHAR   buffer[ 64 ] = { 0 };
        ::GetKeyNameText( keyName, buffer, 64 );

        if( _tcslen( buffer ) > 1 )
        {
            _tcslwr( buffer + 1 );
        }

        os << buffer;

        return os.str();
    }

    BOOL __stdcall SetWindowText( HWND hWnd, const tstring &str )
    {
        return ::SetWindowText( hWnd, str.c_str() );
    }
}

HotKeyCtrlEx::HotKeyCtrlEx() :
    m_hWnd( 0 ),
    m_vkCode( 0 ),
    m_modifiers( 0 ),
    m_activeModifiers( 0 ),
    m_keyHook()
{
}

HotKeyCtrlEx::~HotKeyCtrlEx()
{
    m_keyHook.Shutdown();
}

HotKeyCtrlEx & HotKeyCtrlEx::operator = ( HWND hWnd )
{
    m_hWnd = hWnd;
    m_keyHook.Initialise( this );

    return *this;
}

void HotKeyCtrlEx::GetHotKey( WORD &vkCode, WORD &modifiers )
{
    vkCode = m_vkCode;
    modifiers = m_modifiers;
}

void HotKeyCtrlEx::SetHotKey( WORD vkCode, WORD modifiers )
{
    m_vkCode = vkCode;
    m_modifiers = modifiers;

    ::SetWindowText( m_hWnd, GetHotKeyText( vkCode, modifiers ).c_str() );
}

LRESULT HotKeyCtrlEx::OnKeyDown( const KBDLLHOOKSTRUCT *pks )
{
    WORD    modifier = GetModifier( pks->vkCode );

    if( modifier )
    {
        m_activeModifiers |= modifier;
        return 0;
    }
    else if( ( pks->vkCode == VK_TAB ) && 
             ( CheckFlag( m_activeModifiers, HOTKEYF_CONTROL ) == false ) )
    {
        return 0;
    }
    else
    {
        m_modifiers = m_activeModifiers;

        if( CheckFlag( pks->flags, LLKHF_EXTENDED ) )
        {
            m_modifiers |= HOTKEYF_EXT;
        }
        else
        {
            m_modifiers &= ~HOTKEYF_EXT;
        }

        m_vkCode = static_cast< WORD >( ::MapVirtualKey( pks->scanCode, 1 ) );

        if( ( m_modifiers == 0 ) ||
            ( m_modifiers == HOTKEYF_SHIFT ) )
        {
        //
        // Only function keys are valid hot-keys when used
        // without a modifier
        //
            if( IsFunctionKey( m_vkCode ) == false )
            {
                m_vkCode = 0;
            }
        }

        ::SetWindowText( m_hWnd, GetHotKeyText( m_vkCode, m_modifiers ).c_str() );
        NotifyParent( m_hWnd );
    }

    return 1;
}

LRESULT HotKeyCtrlEx::OnKeyUp( const KBDLLHOOKSTRUCT *pks )
{
    WORD    modifier = GetModifier( pks->vkCode );
    if( modifier )
    {
        m_activeModifiers &= ~modifier;
    }

    return 0;
}

LRESULT HotKeyCtrlEx::OnKeyHook( UINT uMsg, const KBDLLHOOKSTRUCT *pks )
{
    if( GetFocus() == m_hWnd )
    {
        LRESULT ret = 0;

        switch( uMsg )
        {
        case WM_KEYDOWN:
        case WM_SYSKEYDOWN:
            ret = OnKeyDown( pks );
            break;

        case WM_KEYUP:
        case WM_SYSKEYUP:
            ret = OnKeyUp( pks );
            break;
        }

        return ret;
    }

    return 0;
}