// MSAERevert.c

//

// Original version by Jon Lansdell and Nigel Humphreys.

// 4.0 and 3.1 updates by Greg Sutton.

// ©Apple Computer Inc 1996, all rights reserved.

#include "MSAERevert.h"

#include "MSWindow.h"       // for DPtrFromWindowPtr()

#include "MSFile.h"

#include "MSAEUtils.h"

#include "MSAETextUtils.h"

#include "MSAccessors.h"

#include "MSAEDelete.h"

#include "MSAEWindowUtils.h"

#pragma segment File

// -----------------------------------------------------------------------

//  Name:       DoRevert

//  Purpose:    Handles the Revert AppleEvent.

// -----------------------------------------------------------------------

pascal OSErr DoRevert(const AppleEvent  *theAppleEvent,

                            AppleEvent  *reply,

                            long        handlerRefCon)

{ 

#ifdef __MWERKS__

    #pragma unused (reply, handlerRefCon)

#endif

    AEDesc          directObj = {typeNull, NULL};

    WindowToken     aWindowToken;

    OSErr           err;

        // pick up the direct object

    err = AEGetParamDesc(theAppleEvent,  keyDirectObject, typeWildCard, &directObj);

    err = GotRequiredParams(theAppleEvent);

    if (noErr != err) goto done;

    if (typeNull != directObj.descriptorType)

        err = RevertDesc(&directObj);

    else if ( GetNthDocument( 1 ) )             // If no direct object given, default

    {                                           // to the front document.

        aWindowToken.tokenWindow = GetNthDocument( 1 );

        err = RevertDocumentToken( &aWindowToken );

    }

    else

        err = errAENoSuchObject;

done:

    (void)AEDisposeDesc(&directObj);

    return(err);

} // DoRevertWindow

OSErr    RevertDocumentToken(WindowToken* theToken)

{

    DPtr            docPtr;

    TextToken       aTextToken;

    OSErr           err;

    docPtr = DPtrFromWindowPtr(theToken->tokenWindow);

    if (! docPtr)

        return errAEWrongDataType;

                        // Get a token for all the text in the window

    err = TextTokenFromDocumentToken(theToken, &aTextToken);

    if (noErr != err) goto done;

                        // Delete all the text

    err = DeleteTextToken(&aTextToken);

    if (noErr != err) goto done;

    if (docPtr->everSaved) 

    {

        err = GetFileContents(docPtr->theFSSpec, docPtr);

        if (noErr != err) goto done;

        ResizeWindow(docPtr);

        docPtr->dirty = false;

    }

    DoUpdate(docPtr->theWindow);

done:

    return(err);

}

OSErr   RevertDocumentDesc(AEDesc* windowDesc)

{

    WindowToken     aWindowToken;

    Size            actualSize;

    OSErr           err;

    if (typeMyDocument != windowDesc->descriptorType)

        return(errAETypeError);

    GetRawDataFromDescriptor(windowDesc, (Ptr)&aWindowToken, sizeof(aWindowToken), &actualSize);

    err = RevertDocumentToken(&aWindowToken);

    return(err);

}

OSErr   RevertDesc(AEDesc* aDesc)

{

    AEDesc      revertDesc = { typeNull, NULL },

                windowDesc = { typeNull, NULL },

                itemDesc = { typeNull, NULL };

    long        itemCount,

                index;

    DescType    theAEKeyword;

    OSErr       err;

    if ( typeObjectSpecifier == aDesc->descriptorType )

        err = AEResolve( aDesc, kAEIDoMinimum, &revertDesc );

    else if ( typeNull != aDesc->descriptorType )

        err = AEDuplicateDesc( aDesc, &revertDesc );

    if ( noErr != err ) goto done;

    switch ( revertDesc.descriptorType )

    {

        case typeAEList:

            err = AECountItems( &revertDesc, &itemCount );

            if ( noErr != err ) goto done;

            for ( index = 1; index <= itemCount; index++ )  // Do front back order

            {

                err = AEGetNthDesc( &revertDesc, index, typeWildCard,

                                                &theAEKeyword, &itemDesc );

                if ( noErr != err ) goto done;

                err = RevertDesc( &itemDesc );  // Call recursively

                if (noErr != err) goto done;

                (void)AEDisposeDesc( &itemDesc );

            }

            break;

        default:

            err = AECoerceDesc( &revertDesc, typeMyDocument, &windowDesc );

            if ( noErr != err ) goto done;

            err = RevertDocumentDesc( &windowDesc );

    }

done:

    (void)AEDisposeDesc( &revertDesc );

    (void)AEDisposeDesc( &windowDesc );

    (void)AEDisposeDesc( &itemDesc );

    return err;

}