/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */

#include <AzCore/Component/ComponentApplicationBus.h>
#include <AzCore/Component/Entity.h>
#include <AzCore/IO/FileIO.h>
#include <AzCore/IO/GenericStreams.h>
#include <AzCore/Serialization/Json/JsonSerialization.h>
#include <AzCore/Serialization/Json/JsonSerializationResult.h>
#include <AzCore/Serialization/Json/JsonUtils.h>
#include <AzCore/Serialization/SerializeContext.h>
#include <AzCore/Serialization/Utils.h>
#include <AzCore/std/string/string_view.h>
#include <AzFramework/StringFunc/StringFunc.h>
#include <AzToolsFramework/API/EditorAssetSystemAPI.h>
#include <Core/ScriptCanvasBus.h>
#include <GraphCanvas/GraphCanvasBus.h>
#include <ScriptCanvas/Asset/RuntimeAsset.h>
#include <ScriptCanvas/Assets/ScriptCanvasAsset.h>
#include <ScriptCanvas/Assets/ScriptCanvasAssetHandler.h>
#include <ScriptCanvas/Bus/ScriptCanvasBus.h>
#include <ScriptCanvas/Components/EditorGraph.h>
#include <ScriptCanvas/Components/EditorGraphVariableManagerComponent.h>
#include <ScriptCanvas/Components/EditorScriptCanvasComponent.h>
#include <ScriptCanvas/Core/SerializationListener.h>

namespace ScriptCanvasAssetHandlerCpp
{
    using namespace ScriptCanvas;

    void CollectNodes(const GraphData::NodeContainer& container, SerializationListeners& listeners)
    {
        for (auto& nodeEntity : container)
        {
            if (nodeEntity)
            {
                if (auto listener = azrtti_cast<SerializationListener*>(AZ::EntityUtils::FindFirstDerivedComponent<Node>(nodeEntity)))
                {
                    listeners.push_back(listener);
                }
            }
        }
    }
}

namespace ScriptCanvasEditor
{
    ScriptCanvasAssetHandler::ScriptCanvasAssetHandler(AZ::SerializeContext* context)
    {
        SetSerializeContext(context);

        AZ::AssetTypeInfoBus::MultiHandler::BusConnect(GetAssetType());
    }

    ScriptCanvasAssetHandler::~ScriptCanvasAssetHandler()
    {
        AZ::AssetTypeInfoBus::MultiHandler::BusDisconnect();
    }

    AZ::Data::AssetPtr ScriptCanvasAssetHandler::CreateAsset(const AZ::Data::AssetId& id, const AZ::Data::AssetType& type)
    {
        (void)type;
        auto assetData = aznew ScriptCanvasAsset(id);

        AZ::Entity* scriptCanvasEntity = aznew AZ::Entity("Script Canvas Graph");
        SystemRequestBus::Broadcast(&SystemRequests::CreateEditorComponentsOnEntity, scriptCanvasEntity, azrtti_typeid<ScriptCanvas::RuntimeAsset>());

        assetData->SetScriptCanvasEntity(scriptCanvasEntity);

        return assetData;
    }

    // Override the stream info to force source assets to load into the Editor instead of cached, processed assets.
    void ScriptCanvasAssetHandler::GetCustomAssetStreamInfoForLoad(AZ::Data::AssetStreamInfo& streamInfo)
    {
        //ScriptCanvas files are source assets and should be placed in a source asset directory
        const char* assetPath = streamInfo.m_streamName.c_str();
        if (AzFramework::StringFunc::Path::IsRelative(assetPath))
        {
            AZStd::string watchFolder;
            bool sourceInfoFound{};
            AZ::Data::AssetInfo assetInfo;
            AzToolsFramework::AssetSystemRequestBus::BroadcastResult(sourceInfoFound, &AzToolsFramework::AssetSystemRequestBus::Events::GetSourceInfoBySourcePath, assetPath, assetInfo, watchFolder);
            if (sourceInfoFound)
            {
                AzFramework::StringFunc::Path::Join(watchFolder.data(), assetInfo.m_relativePath.data(), streamInfo.m_streamName);
            }
        }
    }

    AZ::Outcome<void, AZStd::string> LoadScriptCanvasDataFromJson
        ( ScriptCanvas::ScriptCanvasData& dataTarget
        , AZStd::string_view source
        , AZ::SerializeContext& serializeContext)
    {
        namespace JSRU = AZ::JsonSerializationUtils;
        using namespace ScriptCanvas;

        AZ::JsonDeserializerSettings settings;
        settings.m_serializeContext = &serializeContext;
        settings.m_metadata.Create<SerializationListeners>();

        auto loadResult = JSRU::LoadObjectFromStringByType
            ( &dataTarget
            , azrtti_typeid<ScriptCanvasData>()
            , source
            , &settings);

        if (!loadResult.IsSuccess())
        {
            return loadResult;
        }
                    
        if (auto graphData = dataTarget.ModGraph())
        {
            auto listeners = settings.m_metadata.Find<SerializationListeners>();
            AZ_Assert(listeners, "Failed to find SerializationListeners");

            ScriptCanvasAssetHandlerCpp::CollectNodes(graphData->GetGraphData()->m_nodes, *listeners);

            for (auto listener : *listeners)
            {
                listener->OnDeserialize();
            }
        }
        else
        {
            return AZ::Failure(AZStd::string("Failed to find graph data after loading source"));
        }

        return AZ::Success();
    }

    AZ::Data::AssetHandler::LoadResult ScriptCanvasAssetHandler::LoadAssetData
        ( const AZ::Data::Asset<AZ::Data::AssetData>& assetTarget
        , AZStd::shared_ptr<AZ::Data::AssetDataStream> streamSource
        , [[maybe_unused]] const AZ::Data::AssetFilterCB& assetLoadFilterCB)
    {
        namespace JSRU = AZ::JsonSerializationUtils;
        using namespace ScriptCanvas;

        auto* scriptCanvasAssetTarget = assetTarget.GetAs<ScriptCanvasAsset>();
        AZ_Assert(scriptCanvasAssetTarget, "This should be a ScriptCanvasAsset, as this is the only type we process!");

        if (m_serializeContext
        && streamSource
        && scriptCanvasAssetTarget)
        {
            streamSource->Seek(0U, AZ::IO::GenericStream::ST_SEEK_BEGIN);
            auto& scriptCanvasDataTarget = scriptCanvasAssetTarget->GetScriptCanvasData();
            AZStd::vector<char> byteBuffer;
            byteBuffer.resize_no_construct(streamSource->GetLength());
            // this duplicate stream is to allow for trying again if the JSON read fails
            AZ::IO::ByteContainerStream<decltype(byteBuffer)> byteStreamSource(&byteBuffer);
            const size_t bytesRead = streamSource->Read(byteBuffer.size(), byteBuffer.data());
            scriptCanvasDataTarget.m_scriptCanvasEntity.reset(nullptr);

            if (bytesRead == streamSource->GetLength())
            {
                byteStreamSource.Seek(0U, AZ::IO::GenericStream::ST_SEEK_BEGIN);
                AZ::JsonDeserializerSettings settings;
                settings.m_serializeContext = m_serializeContext;
                settings.m_metadata.Create<SerializationListeners>();
                // attempt JSON deserialization...
                auto jsonResult = LoadScriptCanvasDataFromJson
                    ( scriptCanvasDataTarget
                    , AZStd::string_view{ byteBuffer.begin(), byteBuffer.size() }
                    , *m_serializeContext);

                if (jsonResult.IsSuccess())
                {
                    return AZ::Data::AssetHandler::LoadResult::LoadComplete;
                }
#if defined(OBJECT_STREAM_EDITOR_ASSET_LOADING_SUPPORT_ENABLED)////
                else
                {
                    // ...if there is a failure, check if it is saved in the old format
                    byteStreamSource.Seek(0U, AZ::IO::GenericStream::ST_SEEK_BEGIN);
                    // tolerate unknown classes in the editor.  Let the asset processor warn about bad nodes...
                    if (AZ::Utils::LoadObjectFromStreamInPlace
                        ( byteStreamSource
                        , scriptCanvasDataTarget
                        , m_serializeContext
                        , AZ::ObjectStream::FilterDescriptor(assetLoadFilterCB, AZ::ObjectStream::FILTERFLAG_IGNORE_UNKNOWN_CLASSES)))
                    {
                        AZ_Warning
                            ( "ScriptCanvas"
                            , false
                            , "ScriptCanvasAssetHandler::LoadAssetData failed to load graph data from JSON, %s, consider converting to JSON"
                                " by opening it and saving it, or running the graph update tool from the editor0"
                            , jsonResult.GetError().c_str());
                        return AZ::Data::AssetHandler::LoadResult::LoadComplete;
                    }
                }
#else
                else
                {
                    AZ_Warning
                        ( "ScriptCanvas"
                        , false
                        , "ScriptCanvasAssetHandler::LoadAssetData failed to load graph data from JSON %s"
                        , jsonResult.GetError().c_str()");
                }
#endif//defined(OBJECT_STREAM_EDITOR_ASSET_LOADING_SUPPORT_ENABLED)
            }
        }

        return AZ::Data::AssetHandler::LoadResult::Error;
    }

    bool ScriptCanvasAssetHandler::SaveAssetData(const AZ::Data::Asset<AZ::Data::AssetData>& asset, AZ::IO::GenericStream* stream)
    {
        return SaveAssetData(asset.GetAs<ScriptCanvasAsset>(), stream);
    }

    bool ScriptCanvasAssetHandler::SaveAssetData(const ScriptCanvasAsset* assetData, AZ::IO::GenericStream* stream)
    {
        return SaveAssetData(assetData, stream, AZ::DataStream::ST_XML);
    }

    bool ScriptCanvasAssetHandler::SaveAssetData
        ( const ScriptCanvasAsset* assetData
        , AZ::IO::GenericStream* stream
        , [[maybe_unused]] AZ::DataStream::StreamType streamType)
    {
        namespace JSRU = AZ::JsonSerializationUtils;
        using namespace ScriptCanvas;

        if (m_serializeContext
        && stream
        && assetData
        && assetData->GetScriptCanvasGraph()
        && assetData->GetScriptCanvasGraph()->GetGraphData())
        {
            auto graphData = assetData->GetScriptCanvasGraph()->GetGraphData();
            AZ::JsonSerializerSettings settings;
            settings.m_metadata.Create<SerializationListeners>();
            auto listeners = settings.m_metadata.Find<SerializationListeners>();
            AZ_Assert(listeners, "Failed to create SerializationListeners");
            ScriptCanvasAssetHandlerCpp::CollectNodes(graphData->m_nodes, *listeners);
            settings.m_keepDefaults = false;
            settings.m_serializeContext = m_serializeContext;

            for (auto listener : *listeners)
            {
                listener->OnSerialize();
            }

            return JSRU::SaveObjectToStream<ScriptCanvasData>(&assetData->GetScriptCanvasData(), *stream, nullptr, &settings).IsSuccess();
        }
        else
        {
            AZ_Error("ScriptCanvas", false, "Saving ScriptCavas assets in the handler requires a valid IO stream, "
                "asset pointer, and serialize context");
            return false;
        }
    }

    void ScriptCanvasAssetHandler::DestroyAsset(AZ::Data::AssetPtr ptr)
    {
        delete ptr;
    }

    AZ::SerializeContext* ScriptCanvasAssetHandler::GetSerializeContext() const
    {
        return m_serializeContext;
    }

    void ScriptCanvasAssetHandler::SetSerializeContext(AZ::SerializeContext* context)
    {
        m_serializeContext = context;

        if (m_serializeContext == nullptr)
        {
            // use the default app serialize context
            EBUS_EVENT_RESULT(m_serializeContext, AZ::ComponentApplicationBus, GetSerializeContext);
            if (!m_serializeContext)
            {
                AZ_Error("Script Canvas", false, "ScriptCanvasAssetHandler: No serialize context provided! "
                    "We will not be able to process Graph Asset type");
            }
        }
    }

    void ScriptCanvasAssetHandler::GetHandledAssetTypes(AZStd::vector<AZ::Data::AssetType>& assetTypes)
    {
        assetTypes.push_back(GetAssetType());
    }

    AZ::Data::AssetType ScriptCanvasAssetHandler::GetAssetType() const
    {
        return ScriptCanvasAssetHandler::GetAssetTypeStatic();
    }

    const char* ScriptCanvasAssetHandler::GetAssetTypeDisplayName() const
    {
        return "Script Canvas";
    }

    AZ::Data::AssetType ScriptCanvasAssetHandler::GetAssetTypeStatic()
    {
        return azrtti_typeid<ScriptCanvasAsset>();
    }

    void ScriptCanvasAssetHandler::GetAssetTypeExtensions(AZStd::vector<AZStd::string>& extensions)
    {
        ScriptCanvasAsset::Description description;
        extensions.push_back(description.GetExtensionImpl());
    }

    AZ::Uuid ScriptCanvasAssetHandler::GetComponentTypeId() const
    {
        return azrtti_typeid<EditorScriptCanvasComponent>();
    }

    const char* ScriptCanvasAssetHandler::GetGroup() const
    {
        return ScriptCanvas::AssetDescription::GetGroup<ScriptCanvasEditor::ScriptCanvasAsset>();
    }

    const char* ScriptCanvasAssetHandler::GetBrowserIcon() const
    {
        return ScriptCanvas::AssetDescription::GetIconPath<ScriptCanvasEditor::ScriptCanvasAsset>();
    }
}