// $Revision: 1.1 $
// AutoDropAcceptor.C
// Copyright (C) 1994, 1995 Taligent, Inc. All rights reserved.

#include "AutoDropAcceptor.h"

#ifndef Taligent_MODELSCRAPITEM
#include <Taligent/ModelScrapItem.h>
#endif

#ifndef TaligentSamples_SIMPLEDRAGANDDROPITEM
#include "SimpleDragAndDropItem.h"
#endif

#ifndef TaligentSamples_INSERTIONTARGET
#include "InsertionTarget.h"
#endif

#ifndef TaligentSamples_HIGHLIGHTFEEDBACKSTYLE
#include "HighlightFeedbackStyle.h"
#endif

#ifndef Taligent_MOUSEDRAGANDDROP
#include <Taligent/MouseDragAndDrop.h>
#endif

#ifndef Taligent_SCRAPITEM
#include <Taligent/ScrapItem.h>
#endif

#ifndef Taligent_COMPOUNDDOCUMENTCOMMAND
#include <Taligent/CompoundDocumentCommand.h>
#endif

//-------------------------- Class MAutoDropAcceptor -------------------

MAutoDropAcceptor::MAutoDropAcceptor()
	: fTarget(NIL)
{
}

MAutoDropAcceptor::MAutoDropAcceptor(TInsertionTarget* target)
	: fTarget(target)
{
}

MAutoDropAcceptor::~MAutoDropAcceptor()
{
}

void
MAutoDropAcceptor::AdoptTarget(TInsertionTarget* target)
{
	fTarget = target;
}

void
MAutoDropAcceptor::DragItemEntered(const TGPoint& where,
	const TSequenceOf<TTypeDescription>& availableTypes)
{
	if (fTarget) {
		fTarget->SetInsertionLocation(where);
		AdjustFeedbackGraphic(availableTypes);
	}
}

void
MAutoDropAcceptor::DragItemMoved(const TGPoint& where,
	const TSequenceOf<TTypeDescription>& availableTypes)
{
	if (fTarget) {
		fTarget->SetInsertionLocation(where);
		AdjustFeedbackGraphic(availableTypes);
	}
}

void
MAutoDropAcceptor::DragItemExited(const TGPoint& where)
{
	if (fTarget) {
		fTarget->SetInsertionLocation(where);
		delete fTarget->OrphanFeedback();
	}
}

bool
MAutoDropAcceptor::ChoosePreferredType(const TGPoint& whereDropped, 
	const TSequenceOf<TTypeDescription>& availableTypes, 
	TTypeDescription& chosenType) const
{
	bool result = false;
	if (fTarget) {
		fTarget->SetInsertionLocation(whereDropped);
	
		MDataExchanger* exchanger;
		DynamicCastTo(exchanger, fTarget->GetSelection());
		TTypeDescription* type = NIL;
		if (exchanger) {
			type = NegotiateType(exchanger, availableTypes);
			if(type) {
				chosenType = *type;
			}
		}
		result = type != NIL;
	}
	return result;
}

bool
MAutoDropAcceptor::AcceptDrop(const TGPoint& whereDropped, const TTypeDescription& type, 
	const TScrapItem& item)
{
	bool result = false;
	
	if (fTarget) {
		const TModelScrapItem* scrap = NIL;
		DynamicCastTo(scrap, &item);
		fTarget->SetInsertionLocation(whereDropped);
		MDataExchanger* exchanger;
		DynamicCastTo(exchanger, fTarget->GetSelection());
		if (exchanger) {
			TModel* data = scrap->CopyModel(type);
			Assertion(data, "MAutoDropAcceptor::AcceptDrop");

			TDocumentComponentWriteEntry entry(fTarget->GetSelection()->GetModelReference());
			delete exchanger->ReplaceData(data);
			result = true;
		}
	}
	return result;
}

void
MAutoDropAcceptor::AdjustFeedbackGraphic(const TSequenceOf<TTypeDescription>& availableTypes)
{
	MDataExchanger* exchanger;
	DynamicCastTo(exchanger, fTarget->GetSelection());
	if (exchanger && NegotiateType(exchanger, availableTypes)) {
		fTarget->AdoptFeedback(
			THighlightFeedbackStyle(TRGBColor(1, .2, .2), 0.5).CreateFeedback(*fTarget));
	}
}

TTypeDescription*
MAutoDropAcceptor::NegotiateType(MDataExchanger* exchanger,
	const TSequenceOf<TTypeDescription>& available) const
{
	TDequeOf<TTypeDescription> chosen(new TOperatorComparator<TTypeDescription>(),
		new TPolymorphicStreamer<TTypeDescription>());
	{
		TDocumentComponentReadEntry entry(fTarget->GetSelection()->GetModelReference());
		exchanger->ChooseTypes(available, chosen);
	}
	TTypeDescription* result = chosen.First();
	chosen.RemoveAll();
	return result;
}