// Copyright 1998-2019 Epic Games, Inc. All Rights Reserved.

#include "AnimGraphNode_SubInstance.h"
#include "Widgets/Text/STextBlock.h"
#include "Widgets/Input/SCheckBox.h"
#include "EdGraphSchema_K2.h"
#include "Kismet2/CompilerResultsLog.h"
#include "Kismet2/BlueprintEditorUtils.h"
#include "PropertyHandle.h"
#include "DetailLayoutBuilder.h"
#include "DetailCategoryBuilder.h"
#include "Animation/AnimNode_SubInput.h"
#include "PropertyCustomizationHelpers.h"
#include "ScopedTransaction.h"
#include "AnimationGraphSchema.h"

#define LOCTEXT_NAMESPACE "SubInstanceNode"

namespace SubInstanceGraphNodeConstants
{
	FLinearColor TitleColor(0.2f, 0.2f, 0.8f);
}

FLinearColor UAnimGraphNode_SubInstance::GetNodeTitleColor() const
{
	return SubInstanceGraphNodeConstants::TitleColor;
}

FText UAnimGraphNode_SubInstance::GetTooltipText() const
{
	return LOCTEXT("ToolTip", "Runs a sub-anim instance to process animation");
}
FText UAnimGraphNode_SubInstance::GetNodeTitle(ENodeTitleType::Type TitleType) const
{
	UClass* TargetClass = *Node.InstanceClass;

	FFormatNamedArguments Args;
	Args.Add(TEXT("NodeTitle"), LOCTEXT("Title", "Sub Anim Instance"));
	Args.Add(TEXT("TargetClass"), TargetClass ? FText::FromString(TargetClass->GetName()) : LOCTEXT("ClassNone", "None"));

	if(TitleType == ENodeTitleType::MenuTitle)
	{
		return LOCTEXT("NodeTitle", "Sub Anim Instance");
	}
	if(TitleType == ENodeTitleType::ListView)
	{
		if(Node.Tag != NAME_None)
		{
			Args.Add(TEXT("Tag"), FText::FromName(Node.Tag));
			return FText::Format(LOCTEXT("TitleListFormatTagged", "{NodeTitle} - Target Class: {TargetClass} - Tag: {Tag}"), Args);
		}
		else
		{
			return FText::Format(LOCTEXT("TitleListFormat", "{NodeTitle} - Target Class: {TargetClass}"), Args);
		}
	}
	else
	{
		if(Node.Tag != NAME_None)
		{
			Args.Add(TEXT("Tag"), FText::FromName(Node.Tag));
			return FText::Format(LOCTEXT("TitleFormatTagged", "{NodeTitle}\nTarget Class: {TargetClass}\nTag: {Tag}"), Args);
		}
		else
		{
			return FText::Format(LOCTEXT("TitleFormat", "{NodeTitle}\nTarget Class: {TargetClass}"), Args);
		}
	}
}

void UAnimGraphNode_SubInstance::ValidateAnimNodeDuringCompilation(USkeleton* ForSkeleton, FCompilerResultsLog& MessageLog)
{
	Super::ValidateAnimNodeDuringCompilation(ForSkeleton, MessageLog);

	UAnimBlueprint* AnimBP = CastChecked<UAnimBlueprint>(GetBlueprint());

	UObject* OriginalNode = MessageLog.FindSourceObject(this);

	// Check we have a class set
	if(!*Node.InstanceClass)
	{
		MessageLog.Error(TEXT("Sub instance node @@ has no valid instance class to spawn."), this);
	}

	if(HasInstanceLoop())
	{
		MessageLog.Error(TEXT("Detected loop in sub instance chain starting at @@ inside class @@"), this, AnimBP->GetAnimBlueprintGeneratedClass());
	}

	// Check for cycles from other sub instance nodes
	TArray<UEdGraph*> Graphs;
	AnimBP->GetAllGraphs(Graphs);

	// Check for duplicate tags in this anim blueprint
	for(UEdGraph* Graph : Graphs)
	{
		TArray<UAnimGraphNode_SubInstance*> SubInstanceNodes;
		Graph->GetNodesOfClass(SubInstanceNodes);

		for(UAnimGraphNode_SubInstance* SubInstanceNode : SubInstanceNodes)
		{
			if(SubInstanceNode == OriginalNode)
			{
				continue;
			}

			FAnimNode_SubInstance& InnerNode = SubInstanceNode->Node;

			if(InnerNode.Tag != NAME_None && InnerNode.Tag == Node.Tag)
			{
				MessageLog.Error(*FText::Format(LOCTEXT("DuplicateTagErrorFormat", "Node @@ and node @@ both have the same tag '{0}'."), FText::FromName(Node.Tag)).ToString(), this, SubInstanceNode);
			}
		}
	}

	// Check we don't try to spawn our own blueprint
	if(*Node.InstanceClass == AnimBP->GetAnimBlueprintGeneratedClass())
	{
		MessageLog.Error(TEXT("Sub instance node @@ targets instance class @@ which it is inside, this would cause a loop."), this, AnimBP->GetAnimBlueprintGeneratedClass());
	}
}

void UAnimGraphNode_SubInstance::ReallocatePinsDuringReconstruction(TArray<UEdGraphPin*>& OldPins)
{
	Super::ReallocatePinsDuringReconstruction(OldPins);

	UClass* TargetClass = *Node.InstanceClass;

	if(!TargetClass)
	{
		// Nothing to search for properties
		return;
	}

	// Need the schema to extract pin types
	const UEdGraphSchema_K2* Schema = CastChecked<UEdGraphSchema_K2>(GetSchema());

	// Default anim schema for util funcions
	const UAnimationGraphSchema* AnimGraphDefaultSchema = GetDefault<UAnimationGraphSchema>();

	bool bShowPose = false;

	// Scan the target class for a sub input node, we only want to show the pose input if
	// we have that node available
	for(TFieldIterator<UProperty> It(TargetClass); It; ++It)
	{
		UProperty* CurrentProp = *It;
		
		if(UStructProperty* StructProp = Cast<UStructProperty>(CurrentProp))
		{
			if(StructProp->Struct->IsChildOf(FAnimNode_SubInput::StaticStruct()))
			{
				// Found a pose input
				bShowPose = true;
				break;
			}
		}
	}

	if(bShowPose)
	{
		if(UProperty* PoseProperty = FindField<UProperty>(FAnimNode_SubInstance::StaticStruct(), GET_MEMBER_NAME_CHECKED(FAnimNode_SubInstance, InPose)))
		{
			FEdGraphPinType PinType;
			if(Schema->ConvertPropertyToPinType(PoseProperty, PinType))
			{
				UEdGraphPin* NewPin = CreatePin(EEdGraphPinDirection::EGPD_Input, PinType, PoseProperty->GetFName());
				NewPin->PinFriendlyName = PoseProperty->GetDisplayNameText();

				CustomizePinData(NewPin, PoseProperty->GetFName(), INDEX_NONE);
			}
		}
	}

	// Grab the list of properties we can expose
	TArray<UProperty*> ExposablePropeties;
	GetExposableProperties(ExposablePropeties);

	// We'll track the names we encounter by removing from this list, if anything remains the properties
	// have been removed from the target class and we should remove them too
	TArray<FName> BeginExposableNames = KnownExposableProperties;

	for(UProperty* Property : ExposablePropeties)
	{
		FName PropertyName = Property->GetFName();
		BeginExposableNames.Remove(PropertyName);

		if(!KnownExposableProperties.Contains(PropertyName))
		{
			// New property added to the target class
			KnownExposableProperties.Add(PropertyName);
		}

		if(ExposedPropertyNames.Contains(PropertyName) && FBlueprintEditorUtils::PropertyStillExists(Property))
		{
			FEdGraphPinType PinType;

			verify(Schema->ConvertPropertyToPinType(Property, PinType));

			UEdGraphPin* NewPin = CreatePin(EEdGraphPinDirection::EGPD_Input, PinType, Property->GetFName());
			NewPin->PinFriendlyName = Property->GetDisplayNameText();

			// Need to grab the default value for the property from the target generated class CDO
			FString CDODefaultValueString;
			uint8* ContainerPtr = reinterpret_cast<uint8*>(TargetClass->GetDefaultObject());

			if(FBlueprintEditorUtils::PropertyValueToString(Property, ContainerPtr, CDODefaultValueString))
			{
				// If we successfully pulled a value, set it to the pin
				Schema->TrySetDefaultValue(*NewPin, CDODefaultValueString);
			}

			CustomizePinData(NewPin, PropertyName, INDEX_NONE);
		}
	}

	// Remove any properties that no longer exist on the target class
	for(FName& RemovedPropertyName : BeginExposableNames)
	{
		KnownExposableProperties.Remove(RemovedPropertyName);
	}
}

void UAnimGraphNode_SubInstance::PostEditChangeProperty(FPropertyChangedEvent& PropertyChangedEvent)
{
	Super::PostEditChangeProperty(PropertyChangedEvent);

	bool bRequiresNodeReconstruct = false;
	UProperty* ChangedProperty = PropertyChangedEvent.Property;

	if(ChangedProperty)
	{
		if(ChangedProperty->GetFName() == GET_MEMBER_NAME_CHECKED(FAnimNode_SubInstance, InstanceClass))
		{
			bRequiresNodeReconstruct = true;
			RebuildExposedProperties(*Node.InstanceClass);
		}
	}

	if(bRequiresNodeReconstruct)
	{
		ReconstructNode();
	}
}

void UAnimGraphNode_SubInstance::GetInstancePinProperty(const UClass* InOwnerInstanceClass, UEdGraphPin* InInputPin, UProperty*& OutProperty)
{
	// The actual name of the instance property
	FString FullName = GetPinTargetVariableName(InInputPin);

	if(UProperty* Property = FindField<UProperty>(InOwnerInstanceClass, *FullName))
	{
		OutProperty = Property;
	}
	else
	{
		OutProperty = nullptr;
	}
}

FString UAnimGraphNode_SubInstance::GetPinTargetVariableName(const UEdGraphPin* InPin) const
{
	return TEXT("__SUBINSTANCE_") + InPin->PinName.ToString() + TEXT("_") + NodeGuid.ToString();
}

void UAnimGraphNode_SubInstance::CustomizeDetails(IDetailLayoutBuilder& DetailBuilder)
{
	Super::CustomizeDetails(DetailBuilder);

	// We dont allow multi-select here
	if(DetailBuilder.GetSelectedObjects().Num() > 1)
	{
		return;
	}

	TArray<UProperty*> ExposableProperties;
	GetExposableProperties(ExposableProperties);

	if(ExposableProperties.Num() > 0)
	{
		IDetailCategoryBuilder& CategoryBuilder = DetailBuilder.EditCategory(FName(TEXT("Sub Instance Properties")));

		for(UProperty* Property : ExposableProperties)
		{
			FDetailWidgetRow& WidgetRow = CategoryBuilder.AddCustomRow(FText::FromString(Property->GetName()));

			FName PropertyName = Property->GetFName();
			FText PropertyTypeText = GetPropertyTypeText(Property);

			FFormatNamedArguments Args;
			Args.Add(TEXT("PropertyName"), FText::FromName(PropertyName));
			Args.Add(TEXT("PropertyType"), PropertyTypeText);

			FText TooltipText = FText::Format(LOCTEXT("PropertyTooltipText", "{PropertyName}\nType: {PropertyType}"), Args);

			WidgetRow.NameContent()
			[
				SNew(STextBlock)
				.Text(FText::FromString(Property->GetName()))
				.ToolTipText(TooltipText)
			];

			WidgetRow.ValueContent()
			[
				SNew(SHorizontalBox)
				+SHorizontalBox::Slot()
				[
					SNew(STextBlock)
					.Text(LOCTEXT("ExposePropertyValue", "Expose: "))
				]
				+SHorizontalBox::Slot()
				[
					SNew(SCheckBox)
					.IsChecked_UObject(this, &UAnimGraphNode_SubInstance::IsPropertyExposed, PropertyName)
					.OnCheckStateChanged_UObject(this, &UAnimGraphNode_SubInstance::OnPropertyExposeCheckboxChanged, PropertyName)
				]
			];
		}
	}

	TSharedRef<IPropertyHandle> ClassHandle = DetailBuilder.GetProperty(TEXT("Node.InstanceClass"), GetClass());
	if(ClassHandle->IsValidHandle())
	{
		ClassHandle->SetOnPropertyValueChanged(FSimpleDelegate::CreateUObject(this, &UAnimGraphNode_SubInstance::OnInstanceClassChanged, &DetailBuilder));
	}

	ClassHandle->MarkHiddenByCustomization();

	IDetailCategoryBuilder& CategoryBuilder = DetailBuilder.EditCategory(FName(TEXT("Settings")));

	FDetailWidgetRow& ClassWidgetRow = CategoryBuilder.AddCustomRow(LOCTEXT("FilterString", "Instance Class"));
	ClassWidgetRow.NameContent()
		[
			ClassHandle->CreatePropertyNameWidget()
		];

	ClassWidgetRow.ValueContent()
		[
			SNew(SObjectPropertyEntryBox)
				.ObjectPath_UObject(this, &UAnimGraphNode_SubInstance::GetCurrentInstanceBlueprintPath)
				.AllowedClass(UAnimBlueprint::StaticClass())
				.NewAssetFactories(TArray<UFactory*>())
				.OnShouldFilterAsset(FOnShouldFilterAsset::CreateUObject(this, &UAnimGraphNode_SubInstance::OnShouldFilterInstanceBlueprint))
				.OnObjectChanged(FOnSetObject::CreateUObject(this, &UAnimGraphNode_SubInstance::OnSetInstanceBlueprint, ClassHandle))
		];
}

FText UAnimGraphNode_SubInstance::GetPropertyTypeText(UProperty* Property)
{
	FText PropertyTypeText;

	if(UStructProperty* StructProperty = Cast<UStructProperty>(Property))
	{
		PropertyTypeText = StructProperty->Struct->GetDisplayNameText();
	}
	else if(UObjectProperty* ObjectProperty = Cast<UObjectProperty>(Property))
	{
		PropertyTypeText = ObjectProperty->PropertyClass->GetDisplayNameText();
	}
	else if(UClass* PropClass = Property->GetClass())
	{
		PropertyTypeText = PropClass->GetDisplayNameText();
	}
	else
	{
		PropertyTypeText = LOCTEXT("PropertyTypeUnknown", "Unknown");
	}
	
	return PropertyTypeText;
}

void UAnimGraphNode_SubInstance::RebuildExposedProperties(UClass* InNewClass)
{
	ExposedPropertyNames.Empty();
	KnownExposableProperties.Empty();
	if(InNewClass)
	{
		TArray<UProperty*> ExposableProperties;
		GetExposableProperties(ExposableProperties);

		for(UProperty* Property : ExposableProperties)
		{
			KnownExposableProperties.Add(Property->GetFName());
		}
	}
}

bool UAnimGraphNode_SubInstance::HasInstanceLoop()
{
	TArray<FGuid> VisitedList;
	TArray<FGuid> CurrentStack;
	return HasInstanceLoop_Recursive(this, VisitedList, CurrentStack);
}

bool UAnimGraphNode_SubInstance::HasInstanceLoop_Recursive(UAnimGraphNode_SubInstance* CurrNode, TArray<FGuid>& VisitedNodes, TArray<FGuid>& NodeStack)
{
	if(!VisitedNodes.Contains(CurrNode->NodeGuid))
	{
		VisitedNodes.Add(CurrNode->NodeGuid);
		NodeStack.Add(CurrNode->NodeGuid);

		if(UAnimBlueprint* AnimBP = Cast<UAnimBlueprint>(UBlueprint::GetBlueprintFromClass(CurrNode->Node.InstanceClass)))
		{
			// Check for cycles from other sub instance nodes
			TArray<UEdGraph*> Graphs;
			AnimBP->GetAllGraphs(Graphs);

			for(UEdGraph* Graph : Graphs)
			{
				TArray<UAnimGraphNode_SubInstance*> SubInstanceNodes;
				Graph->GetNodesOfClass(SubInstanceNodes);

				for(UAnimGraphNode_SubInstance* SubInstanceNode : SubInstanceNodes)
				{
					// If we haven't visited this node, then check it for loops, otherwise if we're pointing to a previously visited node that is in the current instance stack we have a loop
					if((!VisitedNodes.Contains(SubInstanceNode->NodeGuid) && HasInstanceLoop_Recursive(SubInstanceNode, VisitedNodes, NodeStack)) || NodeStack.Contains(SubInstanceNode->NodeGuid))
					{
						return true;
					}
				}
			}
		}
	}

	NodeStack.Remove(CurrNode->NodeGuid);
	return false;
}

ECheckBoxState UAnimGraphNode_SubInstance::IsPropertyExposed(FName PropertyName) const
{
	return ExposedPropertyNames.Contains(PropertyName) ? ECheckBoxState::Checked : ECheckBoxState::Unchecked;
}

void UAnimGraphNode_SubInstance::OnPropertyExposeCheckboxChanged(ECheckBoxState NewState, FName PropertyName)
{
	if(NewState == ECheckBoxState::Checked)
	{
		ExposedPropertyNames.AddUnique(PropertyName);
	}
	else if(NewState == ECheckBoxState::Unchecked)
	{
		ExposedPropertyNames.Remove(PropertyName);
	}

	ReconstructNode();
}

void UAnimGraphNode_SubInstance::OnInstanceClassChanged(IDetailLayoutBuilder* DetailBuilder)
{
	if(DetailBuilder)
	{
		DetailBuilder->ForceRefreshDetails();
	}
}

FString UAnimGraphNode_SubInstance::GetCurrentInstanceBlueprintPath() const
{
	UClass* InstanceClass = *Node.InstanceClass;

	if(InstanceClass)
	{
		UBlueprint* ActualBlueprint = UBlueprint::GetBlueprintFromClass(InstanceClass);

		if(ActualBlueprint)
		{
			return ActualBlueprint->GetPathName();
		}
	}

	return FString();
}

bool UAnimGraphNode_SubInstance::OnShouldFilterInstanceBlueprint(const FAssetData& AssetData) const
{
	FAssetDataTagMapSharedView::FFindTagResult Result = AssetData.TagsAndValues.FindTag("TargetSkeleton");
	if (Result.IsSet())
	{
		if (UAnimBlueprint* CurrentBlueprint = Cast<UAnimBlueprint>(GetBlueprint()))
		{
			FString TargetSkeletonName = FString::Printf(TEXT("%s'%s'"), *CurrentBlueprint->TargetSkeleton->GetClass()->GetName(), *CurrentBlueprint->TargetSkeleton->GetPathName());

			return Result.GetValue() != TargetSkeletonName;
		}
	}

	return false;
}

void UAnimGraphNode_SubInstance::OnSetInstanceBlueprint(const FAssetData& AssetData, TSharedRef<IPropertyHandle> InstanceClassPropHandle)
{
	if(UAnimBlueprint* Blueprint = Cast<UAnimBlueprint>(AssetData.GetAsset()))
	{
		FScopedTransaction Transaction(LOCTEXT("SetBP", "Set Instance Blueprint"));

		Modify();
		
		InstanceClassPropHandle->SetValue(Blueprint->GetAnimBlueprintGeneratedClass());
	}
}

UObject* UAnimGraphNode_SubInstance::GetJumpTargetForDoubleClick() const
{
	UClass* InstanceClass = *Node.InstanceClass;
	
	if(InstanceClass)
	{
		return InstanceClass->ClassGeneratedBy;
	}

	return nullptr;
}

bool UAnimGraphNode_SubInstance::HasExternalDependencies(TArray<class UStruct*>* OptionalOutput /*= NULL*/) const
{
	UClass* InstanceClassToUse = *Node.InstanceClass;

	// Add our instance class... If that changes we need a recompile
	if(InstanceClassToUse && OptionalOutput)
	{
		OptionalOutput->AddUnique(InstanceClassToUse);
	}

	bool bSuperResult = Super::HasExternalDependencies(OptionalOutput);
	return InstanceClassToUse || bSuperResult;
}

void UAnimGraphNode_SubInstance::GetExposableProperties(TArray<UProperty*>& OutExposableProperties) const
{
	OutExposableProperties.Empty();

	UClass* TargetClass = *Node.InstanceClass;

	if(TargetClass)
	{
		const UEdGraphSchema_K2* Schema = CastChecked<UEdGraphSchema_K2>(GetSchema());

		for(TFieldIterator<UProperty> It(TargetClass, EFieldIteratorFlags::IncludeSuper); It; ++It)
		{
			UProperty* CurProperty = *It;
			FEdGraphPinType PinType;

			if(CurProperty->HasAllPropertyFlags(CPF_Edit | CPF_BlueprintVisible) && CurProperty->HasAllFlags(RF_Public) && Schema->ConvertPropertyToPinType(CurProperty, PinType))
			{
				OutExposableProperties.Add(CurProperty);
			}
		}
	}
}

#undef LOCTEXT_NAMESPACE