/*
* All or portions of this file Copyright (c) Amazon.com, Inc. or its affiliates or
* its licensors.
*
* For complete copyright and license terms please see the LICENSE at the root of this
* distribution (the "License"). All use of this software is governed by the License,
* or, if provided, by the license below or the license accompanying this file. Do not
* remove or modify any license notices. This file is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
*/
// Original file Copyright Crytek GMBH or its affiliates, used under license.

#ifndef CRYINCLUDE_CRYCOMMON_BEHAVIORTREE_DECORATOR_H
#define CRYINCLUDE_CRYCOMMON_BEHAVIORTREE_DECORATOR_H
#pragma once

#include "Node.h"

namespace BehaviorTree
{
    // A decorator is a a node that adds functionality to another node
    // without knowing about its internals.
    // Must have exactly one child.
    class Decorator
        : public Node
    {
        typedef Node BaseClass;

    public:
        void SetChild(const INodePtr& child)
        {
            m_child = child;
        }

        virtual LoadResult LoadFromXml(const XmlNodeRef& xml, const LoadContext& context) override
        {
            IF_UNLIKELY (BaseClass::LoadFromXml(xml, context) == LoadFailure)
            {
                return LoadFailure;
            }

            return LoadChildFromXml(xml, context);
        }

        virtual void HandleEvent(const EventContext& context, const Event& event) override
        {
            assert(m_child.get() != NULL);
            if (m_child)
            {
                m_child->SendEvent(context, event);
            }
        }

#ifdef USING_BEHAVIOR_TREE_SERIALIZATION
        void Serialize(Serialization::IArchive& archive)
        {
            archive(m_child, "child", "+<>");
            if (!m_child)
            {
                archive.Error(m_child, "Node must be specified");
            }
        }
#endif

#ifdef USING_BEHAVIOR_TREE_XML_DESCRIPTION_CREATION
        virtual XmlNodeRef CreateXmlDescription() override
        {
            XmlNodeRef xml = GetISystem()->CreateXmlNode("Decorator");
            if (m_child)
            {
                xml->addChild(m_child->CreateXmlDescription());
            }
            return xml;
        }
#endif

    protected:

        LoadResult LoadChildFromXml(const XmlNodeRef& xml, const LoadContext& context)
        {
            IF_UNLIKELY (BaseClass::LoadFromXml(xml, context) == LoadFailure)
            {
                return LoadFailure;
            }

            if (xml->getChildCount() != 1)
            {
                gEnv->pLog->LogError("A decorator must have exactly one child, but the decorator node %s (line %d) has %d nodes", xml->getTag(), xml->getLine(), xml->getChildCount());
                return LoadFailure;
            }

            INodePtr node = context.nodeFactory.CreateNodeFromXml(xml->getChild(0), context);
            if (node)
            {
                SetChild(node);
                return LoadSuccess;
            }

            return LoadFailure;
        }

        virtual void OnInitialize(const UpdateContext& context) override
        {
            BaseClass::OnInitialize(context);
        }

        virtual void OnTerminate(const UpdateContext& context) override
        {
            m_child->Terminate(context);
            BaseClass::OnTerminate(context);
        }

        virtual Status Update(const UpdateContext& context) override
        {
            return m_child->Tick(context);
        }

        INodePtr m_child;
    };
}
#endif // CRYINCLUDE_CRYCOMMON_BEHAVIORTREE_DECORATOR_H