/*

    Implements a preference file and resource io therein. Also handy

    for resource io in any LFile.

    Created 29 Jan 1996 by EGH

    Copyright © 1996, Apple Computer, Inc. All rights reserved.

*/

#include <String_Utils.h>

#include "CPreferences.h"

CPreferences::CPreferences()

{

    mFile = nil;

    mOwnsFile = true;

}

CPreferences::CPreferences(

    LFile *inFile)

{

    mFile = inFile;

    mOwnsFile = false;

}

CPreferences::CPreferences(

    OSType inFileType,

    OSType inFileCreator,

    StringPtr inFileNameP)

{

    mFile = nil;

    mOwnsFile = true;

    FindOrCreatePreferencesFile(inFileType, inFileCreator, inFileNameP);

}

CPreferences::~CPreferences()

{

    if (mOwnsFile && mFile != nil)

        delete mFile;

}

void CPreferences::FindOrCreatePreferencesFile(

    OSType inFileType,

    OSType inFileCreator,

    StringPtr inFileNameP)

{

    OSErr err = noErr;

    FSSpec spec;

    err = FindFolder(

        kOnSystemDisk,

        kPreferencesFolderType,

        true,

        &spec.vRefNum,

        &spec.parID);

    if (err == noErr)

    {

        CopyPStr(inFileNameP, spec.name, sizeof(spec.name));

        mFile = new LFile(spec);

        SetDebugThrow_(debugAction_Nothing); // turn this off as below will probably be thrown

        Try_

        {

            mFile->CreateNewFile(inFileCreator, inFileType, nil);

        }

        Catch_(inErr)

        {

            if (inErr != dupFNErr)

            {

                delete mFile;

                mFile = nil;

            }

            // fall through

        }

        EndCatch_

        SetDebugThrow_(debugAction_Alert);

    }

}

Handle CPreferences::GetPreferenceResource(

    OSType inResType,

    ResIDT inResID)

{

    Handle resH = nil;

    if (mFile != nil)

    {

        Int16

            saveResRef,

            resRef;

        Try_

        {

            saveResRef = ::CurResFile();

            SetDebugThrow_(debugAction_Nothing); // don't bitch unecessarily

            resRef = mFile->OpenResourceFork(fsRdPerm);

            SetDebugThrow_(debugAction_Alert); // ok, start bitching again

            ::UseResFile(resRef); // to force this file to the head of the chainÉ

            resH = ::Get1Resource(inResType, inResID); // Éso that Get1 can be used

                // the resource fork will be closed, so detach it so we don't lose it

            if (resH != nil)

            {

                ::HNoPurge(resH);

                ::DetachResource(resH);

            }

            mFile->CloseResourceFork();

            ::UseResFile(saveResRef);

        }

        Catch_(inErr)

        {

            ::UseResFile(saveResRef);

            // fall through

        } EndCatch_

    }

    return resH;

}

void CPreferences::SavePreferenceResource(

    OSType inResType,

    ResIDT inResID,

    Handle inPrefH)

{

    if (mFile != nil)

    {

        Int16

            saveResRef,

            resRef;

        Handle resH;

        Try_

        {

            saveResRef = ::CurResFile();

            resRef = mFile->OpenResourceFork(fsRdWrPerm);

            ::UseResFile(resRef); // to force this file to the head of the chainÉ

            resH = ::Get1Resource(inResType, inResID); // Éso that Get1 can be used

                // if the resource already exists, update the old one

            if (resH != nil)

            {

                ::HNoPurge(resH);

                ::SetHandleSize(resH, GetHandleSize(inPrefH));

                ::BlockMove(*inPrefH, *resH, GetHandleSize(resH));

                if (::ResError() == noErr)

                {

                    ::ChangedResource(resH);

                    if (::ResError() == noErr)

                    {

                        ::WriteResource(resH);

                        if (::ResError() == noErr)

                            ::ReleaseResource(resH);

                    }

                }

            }

            else

            {

                ::AddResource(inPrefH, inResType, inResID, "\p");

                if (::ResError() == noErr)

                {

                    ::WriteResource(inPrefH);

                    ::DetachResource(inPrefH); // do not throw the handle

                }

            }

            mFile->CloseResourceFork();

            ::UseResFile(saveResRef);

        }

        Catch_(inErr)

        {

            ::UseResFile(saveResRef);

            // fall through

        } EndCatch_

    }

}