// Copyright 1998-2015 Epic Games, Inc. All Rights Reserved.

#include "PropertyEditorPrivatePCH.h"
#include "PropertyNode.h"
#include "PropertyHandleImpl.h"
#include "PropertyEditorHelpers.h"
#include "IPropertyUtilities.h"


FDetailLayoutBuilderImpl::FDetailLayoutBuilderImpl(FClassToPropertyMap& InPropertyMap, const TSharedRef< class IPropertyUtilities >& InPropertyUtilities, const TSharedRef< IDetailsViewPrivate >& InDetailsView)
	: PropertyMap( InPropertyMap )
	, PropertyDetailsUtilities( InPropertyUtilities )
	, DetailsView( *InDetailsView )
	, CurrentCustomizationClass( NULL )
{

}

IDetailCategoryBuilder& FDetailLayoutBuilderImpl::EditCategory( FName CategoryName, const FText& NewLocalizedDisplayName, ECategoryPriority::Type CategoryType )
{
	FText LocalizedDisplayName = NewLocalizedDisplayName;

	// Use a generic name if one was not specified
	if( CategoryName == NAME_None )
	{
		static const FText GeneralString = NSLOCTEXT("DetailLayoutBuilderImpl", "General", "General");
		static const FName GeneralName = *GeneralString.ToString();

		CategoryName = GeneralName;
		LocalizedDisplayName = GeneralString;
	}

	TSharedPtr<FDetailCategoryImpl> CategoryImpl;
	// If the default category map had a category by the provided name, remove it from the map as it is now customized
	if( !DefaultCategoryMap.RemoveAndCopyValue( CategoryName, CategoryImpl ) )
	{
		// Default category map did not have a category by the requested name. Find or add it to the custom map
		TSharedPtr<FDetailCategoryImpl>& NewCategoryImpl = CustomCategoryMap.FindOrAdd( CategoryName );

		if( !NewCategoryImpl.IsValid() )
		{
			NewCategoryImpl = MakeShareable( new FDetailCategoryImpl( CategoryName, SharedThis(this) ) );
			
			// We want categories within a type to display in the order they were added but sorting is unstable so we make unique numbers 
			uint32 SortOrder = (uint32)CategoryType * 1000 + (CustomCategoryMap.Num() - 1);
			NewCategoryImpl->SetSortOrder( SortOrder );
		}
		CategoryImpl = NewCategoryImpl;
	}
	else
	{
		// Custom category should not exist yet as it was in the default category map
		checkSlow( !CustomCategoryMap.Contains( CategoryName ) && CategoryImpl.IsValid() );
		CustomCategoryMap.Add( CategoryName, CategoryImpl );

		// We want categories within a type to display in the order they were added but sorting is unstable so we make unique numbers 
		uint32 SortOrder = (uint32)CategoryType * 1000 + (CustomCategoryMap.Num() - 1);
		CategoryImpl->SetSortOrder( SortOrder );
	}

	CategoryImpl->SetDisplayName( CategoryName, LocalizedDisplayName );

	return *CategoryImpl;
}


TSharedRef<IPropertyHandle> FDetailLayoutBuilderImpl::GetProperty( const FName PropertyPath, const UClass* ClassOutermost, FName InInstanceName )
{	
	TSharedPtr<FPropertyHandleBase> PropertyHandle; 

	TSharedPtr<FPropertyNode> PropertyNodePtr = GetPropertyNode( PropertyPath, ClassOutermost, InInstanceName );
	
	return GetPropertyHandle( PropertyNodePtr );

}

void FDetailLayoutBuilderImpl::HideProperty( const TSharedPtr<IPropertyHandle> PropertyHandle )
{
	if( PropertyHandle.IsValid() && PropertyHandle->IsValidHandle() )
	{
		// Mark the property as customized so it wont show up in the default location
		TSharedPtr<FPropertyNode> PropertyNode = GetPropertyNode( PropertyHandle );
		if( PropertyNode.IsValid() )
		{
			SetCustomProperty( PropertyNode );
		}
	}
}

void FDetailLayoutBuilderImpl::HideProperty( FName PropertyPath, const UClass* ClassOutermost, FName InstanceName )
{
	TSharedPtr<FPropertyNode> PropertyNode = GetPropertyNode( PropertyPath, ClassOutermost, InstanceName );
	if( PropertyNode.IsValid() )
	{
		SetCustomProperty( PropertyNode );
	}
}

void FDetailLayoutBuilderImpl::ForceRefreshDetails()
{
	DetailsView.ForceRefresh();
}

FDetailCategoryImpl& FDetailLayoutBuilderImpl::DefaultCategory( FName CategoryName )
{
	TSharedPtr<FDetailCategoryImpl>& CategoryImpl = DefaultCategoryMap.FindOrAdd( CategoryName );

	if( !CategoryImpl.IsValid() )
	{
		CategoryImpl = MakeShareable( new FDetailCategoryImpl( CategoryName, SharedThis(this) ) );

		// We want categories within a type to display in the order they were added but sorting is unstable so we make unique numbers 
		uint32 SortOrder = (uint32)ECategoryPriority::Default * 1000 + (DefaultCategoryMap.Num() - 1);
		CategoryImpl->SetSortOrder( SortOrder );
	}
	

	CategoryImpl->SetDisplayName( CategoryName, FText::GetEmpty() );
	return *CategoryImpl;
}

void FDetailLayoutBuilderImpl::BuildCategories( const FCategoryMap& CategoryMap, TArray< TSharedRef<FDetailCategoryImpl> >& OutSimpleCategories, TArray< TSharedRef<FDetailCategoryImpl> >& OutAdvancedCategories )
{
	for( FCategoryMap::TConstIterator It(CategoryMap); It; ++It )
	{
		TSharedRef<FDetailCategoryImpl> DetailCategory = It.Value().ToSharedRef();

		const bool bCategoryHiddenByClass = GetDetailsView().IsCategoryHiddenByClass( DetailCategory->GetCategoryName() );

		if( !bCategoryHiddenByClass )
		{
			DetailCategory->GenerateLayout();

			if( DetailCategory->ContainsOnlyAdvanced() )
			{
				OutAdvancedCategories.Add( DetailCategory );
			}
			else
			{
				OutSimpleCategories.Add( DetailCategory );
			}
		}
	}
}

void FDetailLayoutBuilderImpl::GenerateDetailLayout()
{
	AllRootTreeNodes.Empty();

	// Sort by the order in which categories were edited
	struct FCompareFDetailCategoryImpl
	{
		FORCEINLINE bool operator()( TSharedPtr<FDetailCategoryImpl> A, TSharedPtr<FDetailCategoryImpl> B ) const
		{
			return A->GetSortOrder() < B->GetSortOrder();
		}
	};

	// Merge the two category lists and sort them based on priority
	FCategoryMap AllCategories = CustomCategoryMap;
	AllCategories.Append( DefaultCategoryMap );

	TArray< TSharedRef<FDetailCategoryImpl> > SimpleCategories;
	TArray< TSharedRef<FDetailCategoryImpl> > AdvancedOnlyCategories;

	BuildCategories( CustomCategoryMap, SimpleCategories, AdvancedOnlyCategories );
	BuildCategories( DefaultCategoryMap, SimpleCategories, AdvancedOnlyCategories );

	SimpleCategories.Sort( FCompareFDetailCategoryImpl() );
	AdvancedOnlyCategories.Sort( FCompareFDetailCategoryImpl() );

	/** Merge the two category lists in sorted order */
	for( int32 CategoryIndex = 0; CategoryIndex < SimpleCategories.Num(); ++CategoryIndex )
	{
		AllRootTreeNodes.Add( SimpleCategories[CategoryIndex] );
	}

	for( int32 CategoryIndex = 0; CategoryIndex < AdvancedOnlyCategories.Num(); ++CategoryIndex )
	{
		AllRootTreeNodes.Add( AdvancedOnlyCategories[CategoryIndex] );
	}


}

void FDetailLayoutBuilderImpl::FilterDetailLayout( const FDetailFilter& InFilter )
{
	CurrentFilter = InFilter;
	FilteredRootTreeNodes.Empty();

	for( int32 RootNodeIndex = 0; RootNodeIndex < AllRootTreeNodes.Num(); ++RootNodeIndex )
	{
		TSharedRef<IDetailTreeNode>& RootNode = AllRootTreeNodes[RootNodeIndex];

		// No parent
		const bool bParentVisibleDueToFiltering = false;
		RootNode->FilterNode( InFilter );

		if( RootNode->GetVisibility() == ENodeVisibility::Visible )
		{
			FilteredRootTreeNodes.Add( RootNode );
			DetailsView.RequestItemExpanded( RootNode, RootNode->ShouldBeExpanded() );
		}
	}
}

void FDetailLayoutBuilderImpl::SetCurrentCustomizationClass( UClass* CurrentClass, FName VariableName )
{
	CurrentCustomizationClass = CurrentClass;
	CurrentCustomizationVariableName = VariableName;
}

TSharedPtr<FPropertyNode> FDetailLayoutBuilderImpl::GetPropertyNode( const FName PropertyName, const UClass* ClassOutermost, FName InstanceName ) const
{
	TSharedPtr<FPropertyNode> PropertyNode = GetPropertyNodeInternal( PropertyName, ClassOutermost, InstanceName );
	return PropertyNode;
}

/**
 * Parses a path node string into a property and index  The string should be in the format "Property[Index]" for arrays or "Property" for non arrays
 * 
 * @param OutProperty	The property name parsed from the string
 * @param OutIndex		The index of the property in an array (INDEX_NONE if not found)
 */
static void GetPropertyAndIndex( const FString& PathNode, FString& OutProperty, int32& OutIndex )
{
	OutIndex = INDEX_NONE;
	FString FoundIndexStr;
	// Split the text into the property (left of the brackets) and index Right of the open bracket
	if( PathNode.Split( TEXT("["), &OutProperty, &FoundIndexStr, ESearchCase::IgnoreCase, ESearchDir::FromEnd ) )
	{
		// Convert the index string into a number 
		OutIndex = FCString::Atoi( *FoundIndexStr );
	}
	else
	{
		// No index was found, the path node is just the property
		OutProperty = PathNode;
	}
}
/**
 * Finds a child property node from the provided parent node (does not recurse into grandchildren)
 *
 * @param InParentNode	The parent node to locate the child from
 * @param PropertyName	The property name to find
 * @param Index			The index of the property if its in an array
 */
static TSharedPtr<FPropertyNode> FindChildPropertyNode( FPropertyNode& InParentNode, const FString& PropertyName, int32 Index )
{
	TSharedPtr<FPropertyNode> FoundNode(NULL);

	// search each child for a property with the provided name
	for( int32 ChildIndex = 0; ChildIndex < InParentNode.GetNumChildNodes(); ++ChildIndex )
	{
		TSharedPtr<FPropertyNode>& ChildNode = InParentNode.GetChildNode(ChildIndex);
		UProperty* Property = ChildNode->GetProperty();
		if( Property && Property->GetFName() == *PropertyName )
		{
			FoundNode = ChildNode;
			break;
		}
	}

	// Find the array element.
	if( FoundNode.IsValid() && Index != INDEX_NONE )
	{
		// The found node is the top array so get its child which is the actual node
		FoundNode = FoundNode->GetChildNode( Index );
	}

	return FoundNode;
}

TSharedPtr<FPropertyNode> FDetailLayoutBuilderImpl::GetPropertyNode( TSharedPtr<IPropertyHandle> PropertyHandle ) const
{
	TSharedPtr<FPropertyNode> PropertyNode = NULL;
	if( PropertyHandle->IsValidHandle() )
	{
		PropertyNode = StaticCastSharedPtr<FPropertyHandleBase>(PropertyHandle)->GetPropertyNode();
	}

	return PropertyNode;
}

/**
 Contains the location of a property, by path

 Supported format: instance_name'outer.outer.value[optional_index]
 Instance name is needed if multiple UProperties of the same type exist (such as two identical structs, the instance name is one of the struct variable names)
 Items in arrays are indexed by []
 Example setup
*/

TSharedPtr<FPropertyNode> FDetailLayoutBuilderImpl::GetPropertyNodeInternal( const FName PropertyPath, const UClass* ClassOutermost, FName InstanceName ) const
{
	FName PropertyName;
	TArray<FString> PathList;
	PropertyPath.ToString().ParseIntoArray( PathList, TEXT("."), true );

	if( PathList.Num() == 1 )
	{
		PropertyName = FName( *PathList[0] );
	}
	// The class to find properties in defaults to the class currently being customized
	FName ClassName = CurrentCustomizationClass ? CurrentCustomizationClass->GetFName() : NAME_None;
	if( ClassOutermost != NULL )
	{
		// The requested a different class
		ClassName = ClassOutermost->GetFName();
	}

	// Find the outer variable name.  This only matters if there are multiple instances of the same property
	FName OuterVariableName = CurrentCustomizationVariableName;
	if( InstanceName != NAME_None )
	{
		OuterVariableName = InstanceName;
	}

	// If this fails there are no properties associated with the class name provided
	FClassInstanceToPropertyMap* ClassInstanceToPropertyMapPtr = PropertyMap.Find( ClassName );

	if( ClassInstanceToPropertyMapPtr )
	{
		FClassInstanceToPropertyMap& ClassInstanceToPropertyMap = *ClassInstanceToPropertyMapPtr;
		if( OuterVariableName == NAME_None && ClassInstanceToPropertyMap.Num() == 1 )
		{
			// If the outer  variable name still wasnt specified and there is only one instance, just use that
			auto FirstKey = ClassInstanceToPropertyMap.CreateIterator();
			OuterVariableName = FirstKey.Key();
		}

		FPropertyNodeMap* PropertyNodeMapPtr = ClassInstanceToPropertyMap.Find( OuterVariableName );

		if( PropertyNodeMapPtr )
		{
			FPropertyNodeMap& PropertyNodeMap = *PropertyNodeMapPtr;
			// Check for property name fast path first
			if( PropertyName != NAME_None )
			{
				// The property name was ambiguous or not found if this fails.  If ambiguous, it means there are multiple data same typed data structures(components or structs) in the class which
				// causes multiple properties by the same name to exist.  These properties must be found via the path method.
				return PropertyNodeMap.PropertyNameToNode.FindRef( PropertyName );
			}
			else
			{
				// We need to search through the tree for a property with the given path
				TSharedPtr<FPropertyNode> PropertyNode;

				// Path should be in the format A[optional_index].B.C
				if( PathList.Num() )
				{
					// Get the base property and index
					FString Property;
					int32 Index;
					GetPropertyAndIndex( PathList[0], Property, Index );

					// Get the parent most property node which is the one in the map.  Its children need to be searched
					PropertyNode = PropertyNodeMap.PropertyNameToNode.FindRef( FName( *Property ) );
					if( PropertyNode.IsValid() )
					{
						if( Index != INDEX_NONE )
						{
							// The parent is the actual array, its children are array elements
							PropertyNode = PropertyNode->GetChildNode( Index );
						}

						// Search any additional paths for the child
						for( int32 PathIndex = 1; PathIndex < PathList.Num(); ++PathIndex )
						{
							GetPropertyAndIndex( PathList[PathIndex], Property, Index );

							PropertyNode = FindChildPropertyNode( *PropertyNode, Property, Index );
						}
					}
				}

				return PropertyNode;
			}
		}
	}

	return NULL;
}


TSharedRef<IPropertyHandle> FDetailLayoutBuilderImpl::GetPropertyHandle( TSharedPtr<FPropertyNode> PropertyNodePtr )
{
	TSharedPtr<IPropertyHandle> PropertyHandle;
	if( PropertyNodePtr.IsValid() )
	{ 
		TSharedRef<FPropertyNode> PropertyNode = PropertyNodePtr.ToSharedRef();
		FNotifyHook* NotifyHook = GetPropertyUtilities()->GetNotifyHook();

		PropertyHandle = PropertyEditorHelpers::GetPropertyHandle( PropertyNode, NotifyHook, PropertyDetailsUtilities );
	}
	else
	{
		// Invalid handle
		PropertyHandle = MakeShareable( new FPropertyHandleBase( NULL, NULL, NULL) ); 
	}	

	return PropertyHandle.ToSharedRef();
}

void FDetailLayoutBuilderImpl::AddExternalRootPropertyNode( TSharedRef<FPropertyNode> InExternalRootNode )
{
	DetailsView.AddExternalRootPropertyNode( InExternalRootNode );
}

TSharedPtr<FAssetThumbnailPool> FDetailLayoutBuilderImpl::GetThumbnailPool() const
{
	return DetailsView.GetThumbnailPool();
}

bool FDetailLayoutBuilderImpl::IsPropertyVisible( TSharedRef<IPropertyHandle> PropertyHandle ) const
{
	if( PropertyHandle->IsValidHandle() )
	{
		FPropertyAndParent PropertyAndParent(*PropertyHandle->GetProperty(), PropertyHandle->GetParentHandle().IsValid() ? PropertyHandle->GetParentHandle()->GetProperty() : nullptr );

		return IsPropertyVisible(PropertyAndParent);
	}
	
	return false;
}

bool FDetailLayoutBuilderImpl::IsPropertyVisible( const struct FPropertyAndParent& PropertyAndParent ) const
{
	return DetailsView.IsPropertyVisible( PropertyAndParent );
}

const IDetailsView& FDetailLayoutBuilderImpl::GetDetailsView() const
{ 
	return DetailsView; 
}

void FDetailLayoutBuilderImpl::GetObjectsBeingCustomized( TArray< TWeakObjectPtr<UObject> >& OutObjects ) const
{
	OutObjects.Empty();

	// The class to find properties in defaults to the class currently being customized
	FName ClassName = CurrentCustomizationClass ? CurrentCustomizationClass->GetFName() : NAME_None;
	
	if( ClassName != NAME_None && CurrentCustomizationVariableName != NAME_None )
	{
		// If this fails there are no properties associated with the class name provided
		FClassInstanceToPropertyMap* ClassInstanceToPropertyMapPtr = PropertyMap.Find( ClassName );

		if( ClassInstanceToPropertyMapPtr )
		{
			FClassInstanceToPropertyMap& ClassInstanceToPropertyMap = *ClassInstanceToPropertyMapPtr;
		
			FPropertyNodeMap* PropertyNodeMapPtr = ClassInstanceToPropertyMap.Find( CurrentCustomizationVariableName );

			if( PropertyNodeMapPtr )
			{
				FPropertyNodeMap& PropertyNodeMap = *PropertyNodeMapPtr;
				FObjectPropertyNode* ParentObjectProperty = PropertyNodeMap.ParentProperty ? PropertyNodeMap.ParentProperty->AsObjectNode() : NULL;
				if (ParentObjectProperty)
				{
					for (int32 ObjectIndex = 0; ObjectIndex < ParentObjectProperty->GetNumObjects(); ++ObjectIndex)
					{
						OutObjects.Add(ParentObjectProperty->GetUObject(ObjectIndex));
					}
				}
			}
		}
	}
	else
	{
		OutObjects = DetailsView.GetSelectedObjects();
	}
}

const TSharedRef< IPropertyUtilities >& FDetailLayoutBuilderImpl::GetPropertyUtilities() const
{
	return PropertyDetailsUtilities;
}

void FDetailLayoutBuilderImpl::SetCustomProperty( const TSharedPtr<FPropertyNode>& PropertyNode ) 
{
	PropertyNode->SetNodeFlags( EPropertyNodeFlags::IsCustomized, true );
}

void FDetailLayoutBuilderImpl::Tick( float DeltaTime )
{
	for( auto It = TickableNodes.CreateIterator(); It; ++It )
	{
		(*It)->Tick( DeltaTime );
	}
}

void FDetailLayoutBuilderImpl::AddTickableNode( IDetailTreeNode& TickableNode )
{
	TickableNodes.Add( &TickableNode );
}

void FDetailLayoutBuilderImpl::RemoveTickableNode( IDetailTreeNode& TickableNode )
{
	TickableNodes.Remove( &TickableNode );
}

void FDetailLayoutBuilderImpl::SaveExpansionState( const FString& NodePath, bool bIsExpanded )
{
	DetailsView.SaveCustomExpansionState( NodePath, bIsExpanded );
}

bool FDetailLayoutBuilderImpl::GetSavedExpansionState( const FString& NodePath ) const
{
	return DetailsView.GetCustomSavedExpansionState( NodePath );
}