filtrmgr.cpp

Go to the documentation of this file.

// $Id: filtrmgr.cpp 1282 2006-06-09 09:46:49Z alex $
/* @@tag:xara-cn@@ DO NOT MODIFY THIS LINE
================================XARAHEADERSTART===========================
 
               Xara LX, a vector drawing and manipulation program.
                    Copyright (C) 1993-2006 Xara Group Ltd.
       Copyright on certain contributions may be held in joint with their
              respective authors. See AUTHORS file for details.

LICENSE TO USE AND MODIFY SOFTWARE
----------------------------------

This file is part of Xara LX.

Xara LX is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License version 2 as published
by the Free Software Foundation.

Xara LX and its component source files are 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 General Public License for more details.

You should have received a copy of the GNU General Public License along
with Xara LX (see the file GPL in the root directory of the
distribution); if not, write to the Free Software Foundation, Inc., 51
Franklin St, Fifth Floor, Boston, MA  02110-1301 USA


ADDITIONAL RIGHTS
-----------------

Conditional upon your continuing compliance with the GNU General Public
License described above, Xara Group Ltd grants to you certain additional
rights. 

The additional rights are to use, modify, and distribute the software
together with the wxWidgets library, the wxXtra library, and the "CDraw"
library and any other such library that any version of Xara LX relased
by Xara Group Ltd requires in order to compile and execute, including
the static linking of that library to XaraLX. In the case of the
"CDraw" library, you may satisfy obligation under the GNU General Public
License to provide source code by providing a binary copy of the library
concerned and a copy of the license accompanying it.

Nothing in this section restricts any of the rights you have under
the GNU General Public License.


SCOPE OF LICENSE
----------------

This license applies to this program (XaraLX) and its constituent source
files only, and does not necessarily apply to other Xara products which may
in part share the same code base, and are subject to their own licensing
terms.

This license does not apply to files in the wxXtra directory, which
are built into a separate library, and are subject to the wxWindows
license contained within that directory in the file "WXXTRA-LICENSE".

This license does not apply to the binary libraries (if any) within
the "libs" directory, which are subject to a separate license contained
within that directory in the file "LIBS-LICENSE".


ARRANGEMENTS FOR CONTRIBUTION OF MODIFICATIONS
----------------------------------------------

Subject to the terms of the GNU Public License (see above), you are
free to do whatever you like with your modifications. However, you may
(at your option) wish contribute them to Xara's source tree. You can
find details of how to do this at:
  http://www.xaraxtreme.org/developers/

Prior to contributing your modifications, you will need to complete our
contributor agreement. This can be found at:
  http://www.xaraxtreme.org/developers/contribute/

Please note that Xara will not accept modifications which modify any of
the text between the start and end of this header (marked
XARAHEADERSTART and XARAHEADEREND).


MARKS
-----

Xara, Xara LX, Xara X, Xara X/Xtreme, Xara Xtreme, the Xtreme and Xara
designs are registered or unregistered trademarks, design-marks, and/or
service marks of Xara Group Ltd. All rights in these marks are reserved.


      Xara Group Ltd, Gaddesden Place, Hemel Hempstead, HP2 6EX, UK.
                        http://www.xara.com/

=================================XARAHEADEREND============================
 */

#include "camtypes.h"
#include "filtrmgr.h"

//#include "filters.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "fileform.h"

#if defined(DEBUG_THIS)
#include "plgnfltr.h"
#endif

DECLARE_SOURCE("$Revision: 1282 $");

CC_IMPLEMENT_MEMDUMP(FilterManager, CC_CLASS_MEMDUMP)
CC_IMPLEMENT_MEMDUMP(FileFormat, CC_CLASS_MEMDUMP)
CC_IMPLEMENT_MEMDUMP(FilterList, List)
CC_IMPLEMENT_MEMDUMP(FormatEntry, CC_CLASS_MEMDUMP)
CC_IMPLEMENT_MEMDUMP(FilterEntry, CC_CLASS_MEMDUMP)

// Declare smart memory handling in Debug builds
#define new CAM_DEBUG_NEW

/********************************************************************************************

>   FilterManager::FilterManager()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    22/02/94
    Purpose:    Set the Filter object up to be in a clean state.
    SeeAlso:    Filter; Filter::~Filter; OILFilter

********************************************************************************************/
FilterManager::FilterManager() :
    FILTERID_START(FILTERID_ALDUS_END + 1),
    FORMATID_START(1)
{
    m_NextFilterID      = FILTERID_START;
    m_NextFormatID      = FORMATID_START;
}


/********************************************************************************************

>   FilterID FilterManager::GetNewFilterID()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Returns:    A FilterID unique to this FilterManager for each call to the function
    Purpose:    Support function providing an unique ID for each newly registered Filter

********************************************************************************************/
UINT32 FilterManager::GetNewFilterID()
{
    ERROR3IF(!m_NextFilterID, "Creating duff FilterID");

    return m_NextFilterID++;
}


/********************************************************************************************

>   FilterID FilterManager::RegisterFilter( const Filter* const pFilter, 
                                            const DESTRUCTION_METHOD DestructMethod)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    15/12/94
    Inputs:     pFilter:    pointer to the filter to register
    Returns:    FilterID that uniquely identifies the given filter within the scope of this
                FilterManager and allows for fast retrieval of the filter.
    Purpose:    Permits the filter to be used by the FilterManager.
                For an import filter to be present on the Import dialog the filter should
                associate itself with the requisite FileFormats via AssociateFilterWithFormat()

********************************************************************************************/

UINT32 FilterManager::RegisterFilter(   Filter* const pFilter, 
                                    const DESTRUCTION_METHOD DestructMethod)
{
    //DestructMethod; // This line just read "DestructMethod;" - what's that meant to do then?
    UINT32 newID = Filter::RegisterFilter(pFilter);

    return newID;
}



/********************************************************************************************

>   BOOL FilterManager::Init()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    22/12/96
    Returns:    TRUE if initialised ok, FALSE if not.
    Purpose:    Initializes the filter manager
                Currently just does some tests

********************************************************************************************/

BOOL FilterManager::Init()
{
#if defined(DEBUG_THIS)

    String_256 MyFormatName = _T("myFormat");
    String_256 MyFormatDesc = _T("Format (*.frm)");
    XtraFileFormat* pFormat = new XtraFileFormat(MyFormatName, MyFormatDesc);
    FileFormatID myFormatID = RegisterFileFormat((FileFormat*)pFormat, FilterManager::DM_DELETE_WHEN_DONE);
    MyFormatDesc = _T(".fm1");
    pFormat->AddExtension(MyFormatDesc);
    MyFormatDesc = _T(".fm2");
    pFormat->AddExtension(MyFormatDesc);
    MyFormatDesc = _T(".fm3");
    pFormat->AddExtension(MyFormatDesc);
    MyFormatDesc = _T(".fm2");
    pFormat->AddExtension(MyFormatDesc);
    MyFormatDesc = _T(".one long mother of an extension well beyond thirty-two");
    pFormat->AddExtension(MyFormatDesc);

#endif

    // All ok
    return TRUE;
}


/********************************************************************************************

>   BOOL FilterManager::DeInit()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    22/12/96
    Purpose:    Destroy all the FileFormat objects, maybe

********************************************************************************************/

BOOL FilterManager::DeInit()
{
    for (UINT32 index = 0; index < GetLastFormatID(); index++)
    {
        FormatEntry* pEntry = GetFormats()[index];
        ERROR2IF(pEntry == NULL, FALSE, "pEntry NULL");

        FileFormat* pFormat = pEntry->GetFormat();
        ERROR2IF(pFormat == NULL, FALSE, "pFormat NULL");

        if (pEntry->GetDestructionMethod() == DM_DELETE_WHEN_DONE)
        {
            delete pFormat;
        }
        delete pEntry;
        GetFormats()[index] = NULL;
    }

    // All ok
    return TRUE;
}



#define ADD_FILTER(Classname, FilterIDConst) \
    /* Create, initialise and install the Generic import filter */                  \
    pFilter = new Classname;                                                        \
    if (pFilter == NULL) return FALSE;                                              \
                                                                                    \
    if (!pFilter->Init())                                                           \
    {                                                                               \
        /* Error occured - report it and stop trying to initialise filters. */      \
        InformError();                                                              \
        return TRUE;                                                                \
    }                                                                               \
                                                                                    \
    FilterIDConst = RegisterFilter(pFilter, DM_DELETE_WHEN_DONE);                   \
    if (FilterIDConst == NULL)                                                      \
    {                                                                               \
        return FALSE;                                                               \
    }                                                                               \


/********************************************************************************************

>   Filter* FilterManager::FindFilterFromID(const UINT32 FilterID) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Provides the Filter given its ID

********************************************************************************************/
Filter* FilterManager::FindFilterFromID(const UINT32 FilterID) const
{
    Filter* pFilter = Filter::GetFirst();
    while (pFilter != NULL)
    {
        if (pFilter->FilterID == FilterID)
        {
            break;
        }
        pFilter = Filter::GetNext(pFilter);
    }
    return pFilter;
}



/********************************************************************************************

>   FormatArray& FilterManager::GetFormats()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Returns:    A reference to the FormatArray
    Purpose:    Support function providing access to the FileFormats

********************************************************************************************/
FormatArray& FilterManager::GetFormats()
{
    return m_Formats;
}
    
/********************************************************************************************

>   FileFormatID FilterManager::GetNewFormatID()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Returns:    A FileFormatID unique to this FilterManager for each call to the function
    Purpose:    Support function providing an unique ID for each newly registered FileFormat

********************************************************************************************/
FileFormatID FilterManager::GetNewFormatID()
{
    return m_NextFormatID++;
}


/********************************************************************************************

>   FileFormatID FilterManager::RegisterFileFormat(const FileFormat* pFormat, 
                                                const DESTRUCTION_METHOD dm)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Inputs:     pFormat:    A pointer to the FileFormat to register
    Returns:    A FileFormatID by which the given FileFormat can be uniquely identified and
                quickly retrieved.
    Purpose:    Registers the given FileFormat with this FilterManager

********************************************************************************************/
FileFormatID FilterManager::RegisterFileFormat( FileFormat* const pFormat, 
                                                const DESTRUCTION_METHOD DestructMethod)
{
    ERROR2IF(pFormat == NULL, 0, "NULL Args");

    // Look for one we might already have
    FileFormatID IDToReturn = FindFormatIDFromName(pFormat->GetName());
    if (IDToReturn == 0)
    {
        // Have to add a new one
        IDToReturn = GetNewFormatID();
        FormatEntry* pFormatEntry = new FormatEntry(IDToReturn, pFormat, DestructMethod);
        if (pFormatEntry == NULL)
        {
            goto AddFormatError;
        }

        if (!GetFormats().Add(pFormatEntry))
        {
            delete pFormatEntry;
            goto AddFormatError;
        }
    }
    else
    {
        // Use the duplicate then
    }
    
    return IDToReturn;

AddFormatError:

    return 0;
}


/********************************************************************************************

>   BOOL FilterManager::AssociateFilterWithFormat(  const FilterID FilterID, 
                                                    const FileFormatID FileFormatID)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Inputs:     FilterID:   The FilterID (returned by RegisterFilter()) of the filter to
                            associate with the given FileFormatID
                FileFormatID:   Like FilterID
    Purpose:    Tells this FilterManager that the given filter wishes to be considered when
                doing things with the given format.

********************************************************************************************/
BOOL FilterManager::AssociateFilterWithFormat(  const UINT32 FilterID, 
                                                const FileFormatID FileFormatID)
{
    BOOL Successful = TRUE;     // value to return

    Filter* pFilter             = FindFilterFromID(FilterID);
    FormatEntry* pFormatEntry   = FindFormatEntryFromID(FileFormatID);

    if (pFilter != NULL && pFormatEntry != NULL)
    {
        // We found both the filter & format so create a new association entry
        Successful = pFormatEntry->GetFilters().AddFilter(pFilter, FilterID);
    }
    else
    {
        Successful = FALSE;
    }
    
    return Successful;
}


/********************************************************************************************

>   FileFormatID FilterManager::FindFormatIDFromName(const StringBase& FormatName) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Relief function returning the FileFormat ID instead of the FileFormat per se
    See Also:   Other overloaded function

********************************************************************************************/
FileFormatID FilterManager::FindFormatIDFromName(const StringBase& FormatName) const
{
    FileFormatID FoundID = 0;
    FormatEntry* pFoundEntry = FindFormatEntryFromName(FormatName);

    if (pFoundEntry != NULL)
    {
        FoundID = pFoundEntry->GetID();
    }
    else
    {
        FoundID = 0;
    }

    return FoundID;
}
        
/********************************************************************************************

>   FileFormat* FilterManager::FindFormatFromName(const StringBase& FormatName) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Inputs:     FormatName: The name of a FileFormat given in the FileFormat's constructor
                            which has subsequently been Added to this FilterManager.
    Returns:    A pointer to the FileFormat with the name given or NULL if none was found
    Purpose:    Finds the one & only FileFormat with the given FormatName
                Used by Xtra's mainly

********************************************************************************************/
FileFormat* FilterManager::FindFormatFromName(const StringBase& FormatName) const
{
    FormatEntry* pEntry = FindFormatEntryFromName(FormatName);
    if (pEntry != NULL)
    {
        return pEntry->GetFormat();
    }
    return NULL;
}


/********************************************************************************************

>   FileFormat* FilterManager::FindFormatFromID(const FileFormatID FormatID) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Provides the FileFormat given its ID
    See Also:   FindFormatEntryFromID

********************************************************************************************/
FileFormat* FilterManager::FindFormatFromID(const FileFormatID FormatID) const
{
    FileFormat* pReturnedFormat;

    FormatEntry* pEntry = FindFormatEntryFromID(FormatID);
    if (pEntry != NULL)
    {
        pReturnedFormat = pEntry->GetFormat();
    }
    else
    {
        pReturnedFormat = NULL;
    }

    return pReturnedFormat;
}


/********************************************************************************************

>   FormatEntry* FilterManager::FindFormatEntryFromID(const FileFormatID) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Internally does the actual finding by ID
    See Also:   FindFormatFromID

********************************************************************************************/
FormatEntry* FilterManager::FindFormatEntryFromID(const FileFormatID FormatID) const
{
    ERROR2IF(FormatID == 0 || FormatID > GetLastFormatID(), NULL, 
                "Invalid FileFormatID");

    return GetFormats()[FormatID - 1];
}


/********************************************************************************************

>   FormatEntry* FilterManager::FindFormatEntryFromName(const StringBase& FormatName) const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Inputs:     FormatName: The name of a FileFormat given in the FileFormat's constructor
                            which has subsequently been Added to this FilterManager.
    Returns:    A pointer to the FileFormat with the name given or NULL if none was found
    Purpose:    Finds the one & only FileFormat with the given FormatName
                Used by Xtra's mainly

********************************************************************************************/
FormatEntry* FilterManager::FindFormatEntryFromName(const StringBase& FormatName) const
{
    for (UINT32 index = 0; index < GetLastFormatID(); ++index)
    {
        FormatEntry* pFormatEntry = GetFormats()[index];
        if (pFormatEntry != NULL)
        {
            FileFormat* pFormat = pFormatEntry->GetFormat();
            if (pFormat->GetName() == FormatName)
            {
                return pFormatEntry;
            }
        }
        else
        {
            // we'll ignore this one
        }
    }

    return NULL;
}



/********************************************************************************************

>   Filter* FilterManager::FindMatchedFilter(SearchCriteria)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    To find a filter with the given SearchCriteria
    Notes:      Returns the first matching filter within the context of the given
                SearchCriteria (the SearchContext is contained within the SearchCriteria)

********************************************************************************************/
Filter* FilterManager::FindFilter(FilterSearchCriteria& Criteria) const
{
    return NULL;
}


/********************************************************************************************

>   FilterList* FilterManager::ListMatchingFilters(FilterSearchCriteria& Criteria)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Creates a list of filters matching the given FilterSearchCriteria
    Returns:    A list of filters matching the given FilterSearchCriteria. The list IsEmpty
                if no filters matched
                NULL if failed
    Notes:      The returned list should be deleted when finished with.

********************************************************************************************/
FilterList* FilterManager::ListMatchingFilters(FilterSearchCriteria& Criteria)
{
    FilterList* pList = new FilterList;

    return pList;
}



/********************************************************************************************

>   FormatEntry::FormatEntry(const FileFormatID ID, const FileFormat* pFormat, 
                const FilterManager::DESTRUCTION_METHOD DestructMethod)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Inputs:     ID:             The FileFormat's ID
                pFormat:        A pointer to the FileFormat
                DestructMethod: Whether or not the FileFormat should be deleted when this
                                FormatEntry is.
    Purpose:    Provides an entry for the FilterManager's database of FileFormats

********************************************************************************************/
FormatEntry::FormatEntry(const FileFormatID ID, FileFormat* const pFormat, 
                const FilterManager::DESTRUCTION_METHOD DestructMethod)
{
    m_pFormat           = pFormat;
    m_FormatID          = ID;
    m_DestructMethod    = DestructMethod;
}



/********************************************************************************************

>   FormatEntry::~FormatEntry()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10/12/96
    Purpose:    Default constructor deleting associated FilterEntry items

********************************************************************************************/
FormatEntry::~FormatEntry()
{
    GetFilters().DeleteAll();
}


/********************************************************************************************

>   FilterList::FilterList()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com> (from Tim)
    Created:    28/03/94
    Purpose:    Initialises a list

********************************************************************************************/
FilterList::FilterList()
{
}


/********************************************************************************************

>   FilterEntry::FilterEntry(Filter* pFilter, FilterID ID)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com> (from Tim)
    Created:    28/03/94
    Inputs:     pFilter: the filter contained within this FilterItem
                ID - a unique ID for the given filter
    Purpose:    Initialises a list item for a Filter

********************************************************************************************/
FilterEntry::FilterEntry(Filter* const pFilter, const UINT32 ID)
{
    ERROR3IF(pFilter == NULL || !ID, "FilterListItem - pFilter NULL");

    m_pFilter   = pFilter;
    m_FilterID  = ID;
}


/********************************************************************************************

>   BOOL FilterList::AddFilter(Filter* const pFilter, const FilterID ID)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com> (from Tim)
    Created:    28/03/94
    Inputs:     pEntry: the FilterEntry to add to the list.
    Returns:    TRUE if the filter was added to the list ok; FALSE if not.
    Purpose:    Add a new item to the compatible filter list, which points to the given
                filter, and stores the given compatibility rating in the list entry.
                The list is kept in sorted order, i.e. the list item is added to the list
                according to its compatibility rating; the higher the rating, the closer
                it is to the head of the list.
    Errors:     Out of memory.
    SeeAlso:    ComaptibleFilterList; CompatibleFilter

********************************************************************************************/
BOOL FilterList::AddFilter(Filter* const pFilter, const UINT32 ID)
{
    // Make a new list item for this filter.
    FilterEntry* pEntry = new FilterEntry(pFilter, ID);
    if (pEntry == NULL)
    {
        return FALSE;
    }

    AddTail(pEntry);    // can't fail

    // All ok
    return TRUE;
}

---