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

#include "Customizations/TextureDetailsCustomization.h"
#include "Misc/MessageDialog.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Engine/Texture.h"
#include "Engine/Texture2D.h"
#include "Editor.h"
#include "DetailLayoutBuilder.h"
#include "DetailWidgetRow.h"
#include "IDetailPropertyRow.h"
#include "DetailCategoryBuilder.h"
#include "Widgets/Input/SNumericEntryBox.h"
#include "Widgets/Input/STextComboBox.h"

#define LOCTEXT_NAMESPACE "FTextureDetails"


TSharedRef<IDetailCustomization> FTextureDetails::MakeInstance()
{
	return MakeShareable(new FTextureDetails);
}

void FTextureDetails::CustomizeDetails(IDetailLayoutBuilder& DetailBuilder)
{
	TArray< TWeakObjectPtr<UObject> > ObjectsBeingCustomized;
	DetailBuilder.GetObjectsBeingCustomized(ObjectsBeingCustomized);
	if (ensure(ObjectsBeingCustomized.Num() == 1))
	{
		TextureBeingCustomized = ObjectsBeingCustomized[0];
	}

	MaxTextureSizePropertyHandle = DetailBuilder.GetProperty(GET_MEMBER_NAME_CHECKED(UTexture, MaxTextureSize));
	PowerOfTwoModePropertyHandle = DetailBuilder.GetProperty(GET_MEMBER_NAME_CHECKED(UTexture, PowerOfTwoMode));

	// Customize MaxTextureSize
	if( MaxTextureSizePropertyHandle->IsValidHandle() )
	{
		IDetailCategoryBuilder& CompressionCategory = DetailBuilder.EditCategory("Compression");
		IDetailPropertyRow& MaxTextureSizePropertyRow = CompressionCategory.AddProperty(GET_MEMBER_NAME_CHECKED(UTexture, MaxTextureSize));
		TSharedPtr<SWidget> NameWidget;
		TSharedPtr<SWidget> ValueWidget;
		FDetailWidgetRow Row;
		MaxTextureSizePropertyRow.GetDefaultWidgets(NameWidget, ValueWidget, Row);

		int32 MaxTextureSize = 2048;

		if (UTexture* Texture = Cast<UTexture>(TextureBeingCustomized.Get()))
		{
			MaxTextureSize = Texture->GetMaximumDimension();
		}

		const bool bShowChildren = true;
		MaxTextureSizePropertyRow.CustomWidget(bShowChildren)
			.NameContent()
			.MinDesiredWidth(Row.NameWidget.MinWidth)
			.MaxDesiredWidth(Row.NameWidget.MaxWidth)
			[
				NameWidget.ToSharedRef()
			]
			.ValueContent()
			.MinDesiredWidth(Row.ValueWidget.MinWidth)
			.MaxDesiredWidth(Row.ValueWidget.MaxWidth)
			[
				SNew(SNumericEntryBox<int32>)
				.AllowSpin(true)
				.Value(this, &FTextureDetails::OnGetMaxTextureSize)
				.Font(IDetailLayoutBuilder::GetDetailFont())
				.MinValue(0)
				.MaxValue(MaxTextureSize)
				.MinSliderValue(0)
				.MaxSliderValue(MaxTextureSize)
				.OnValueChanged(this, &FTextureDetails::OnMaxTextureSizeChanged)
				.OnValueCommitted(this, &FTextureDetails::OnMaxTextureSizeCommitted)
				.OnBeginSliderMovement(this, &FTextureDetails::OnBeginSliderMovement)
				.OnEndSliderMovement(this, &FTextureDetails::OnEndSliderMovement)
			];
	}

	// Customize PowerOfTwoMode
	if( PowerOfTwoModePropertyHandle->IsValidHandle() )
	{
		IDetailCategoryBuilder& TextureCategory = DetailBuilder.EditCategory("Texture");
		IDetailPropertyRow& PowerOfTwoModePropertyRow = TextureCategory.AddProperty(GET_MEMBER_NAME_CHECKED(UTexture, PowerOfTwoMode));

		PowerOfTwoModePropertyHandle->SetOnPropertyResetToDefault(FSimpleDelegate::CreateSP(this, &FTextureDetails::OnPropertyResetToDefault));

		// Generate a list of enum values for the combo box
		TArray<FText> PowerOfTwoModeComboBoxToolTips;
		TArray<bool> RestrictedList;
		PowerOfTwoModePropertyHandle->GeneratePossibleValues(PowerOfTwoModeComboBoxList, PowerOfTwoModeComboBoxToolTips, RestrictedList);

		uint8 PowerOfTwoMode;
		ensure(PowerOfTwoModePropertyHandle->GetValue(PowerOfTwoMode) == FPropertyAccess::Success);

		TSharedPtr<SWidget> NameWidget;
		TSharedPtr<SWidget> ValueWidget;
		FDetailWidgetRow Row;
		PowerOfTwoModePropertyRow.GetDefaultWidgets(NameWidget, ValueWidget, Row);

		const bool bShowChildren = true;
		PowerOfTwoModePropertyRow.CustomWidget(bShowChildren)
			.NameContent()
			.MinDesiredWidth(Row.NameWidget.MinWidth)
			.MaxDesiredWidth(Row.NameWidget.MaxWidth)
			[
				NameWidget.ToSharedRef()
			]
			.ValueContent()
			.MinDesiredWidth(Row.ValueWidget.MinWidth)
			.MaxDesiredWidth(Row.ValueWidget.MaxWidth)
			[
				SAssignNew(TextComboBox, STextComboBox)
				.Font(IDetailLayoutBuilder::GetDetailFont())
				.OptionsSource(&PowerOfTwoModeComboBoxList)
				.InitiallySelectedItem(PowerOfTwoModeComboBoxList[PowerOfTwoMode])
				.OnSelectionChanged(this, &FTextureDetails::OnPowerOfTwoModeChanged)
			];
	}
}

bool FTextureDetails::CanEditMaxTextureSize() const
{
	if (UTexture2D* Texture2D = Cast<UTexture2D>(TextureBeingCustomized.Get()))
	{
		if (!Texture2D->Source.IsPowerOfTwo() && Texture2D->PowerOfTwoMode == ETexturePowerOfTwoSetting::None)
		{
			return false;
		}
	}

	return true;
}

void FTextureDetails::CreateMaxTextureSizeMessage() const
{
	FMessageDialog::Open(EAppMsgType::Ok,
		LOCTEXT("CannotEditMaxTextureSize", "Maximum Texture Size cannot be changed for this texture as it is a non power of two size. Change the Power of Two Mode to allow it to be padded to a power of two."));
}

/** @return The value or unset if properties with multiple values are viewed */
TOptional<int32> FTextureDetails::OnGetMaxTextureSize() const
{
	int32 NumericVal;
	if (MaxTextureSizePropertyHandle->GetValue(NumericVal) == FPropertyAccess::Success)
	{
		return NumericVal;
	}

	// Return an unset value so it displays the "multiple values" indicator instead
	return TOptional<int32>();
}

void FTextureDetails::OnMaxTextureSizeChanged(int32 NewValue)
{
	if (!CanEditMaxTextureSize())
	{
		return;
	}

	if (bIsUsingSlider)
	{
		int32 OrgValue(0);
		if (MaxTextureSizePropertyHandle->GetValue(OrgValue) != FPropertyAccess::Fail)
		{
			// Value hasn't changed, so let's return now
			if (OrgValue == NewValue)
			{
				return;
			}
		}

		// We don't create a transaction for each property change when using the slider.  Only once when the slider first is moved
		EPropertyValueSetFlags::Type Flags = (EPropertyValueSetFlags::InteractiveChange | EPropertyValueSetFlags::NotTransactable);
		MaxTextureSizePropertyHandle->SetValue(NewValue, Flags);
	}
}

void FTextureDetails::OnMaxTextureSizeCommitted(int32 NewValue, ETextCommit::Type CommitInfo)
{
	if (!CanEditMaxTextureSize())
	{
		if (CommitInfo == ETextCommit::OnEnter)
		{
			CreateMaxTextureSizeMessage();
		}
		return;
	}

	MaxTextureSizePropertyHandle->SetValue(NewValue);
}

/**
 * Called when the slider begins to move.  We create a transaction here to undo the property
 */
void FTextureDetails::OnBeginSliderMovement()
{
	if (!CanEditMaxTextureSize())
	{
		return;
	}

	bIsUsingSlider = true;

	GEditor->BeginTransaction(TEXT("TextureDetails"), LOCTEXT("SetMaximumTextureSize", "Edit Maximum Texture Size"), MaxTextureSizePropertyHandle->GetProperty());
}


/**
 * Called when the slider stops moving.  We end the previously created transaction
 */
void FTextureDetails::OnEndSliderMovement(int32 NewValue)
{
	if (!CanEditMaxTextureSize())
	{
		return;
	}

	bIsUsingSlider = false;

	GEditor->EndTransaction();
}

bool FTextureDetails::CanEditPowerOfTwoMode(int32 NewPowerOfTwoMode) const
{
	if (UTexture2D* Texture2D = Cast<UTexture2D>(TextureBeingCustomized.Get()))
	{
		if (!Texture2D->Source.IsPowerOfTwo() && Texture2D->MaxTextureSize > 0 && NewPowerOfTwoMode == ETexturePowerOfTwoSetting::None)
		{
			return false;
		}
	}

	return true;
}

void FTextureDetails::CreatePowerOfTwoModeMessage() const
{
	FMessageDialog::Open(EAppMsgType::Ok,
						 LOCTEXT("CannotEditPowerOfTwoMode", "Power of Two Mode cannot be changed to None for this texture as it is a non power of two size and has a Maximum Texture Size override. Change the Maximum Texture Size to 0 before attempting to change the Power of Two Mode."));
}

void FTextureDetails::OnPropertyResetToDefault() const
{
	uint8 CurrentPowerOfTwoMode;
	ensure(PowerOfTwoModePropertyHandle->GetValue(CurrentPowerOfTwoMode) == FPropertyAccess::Success);
	TextComboBox->SetSelectedItem(PowerOfTwoModeComboBoxList[CurrentPowerOfTwoMode]);
}

void FTextureDetails::OnPowerOfTwoModeChanged(TSharedPtr<FString> NewValue, ESelectInfo::Type SelectInfo)
{
	int32 NewPowerOfTwoMode = PowerOfTwoModeComboBoxList.Find(NewValue);
	check(NewPowerOfTwoMode != INDEX_NONE);
	if (!CanEditPowerOfTwoMode(NewPowerOfTwoMode))
	{
		CreatePowerOfTwoModeMessage();
		uint8 CurrentPowerOfTwoMode;
		ensure(PowerOfTwoModePropertyHandle->GetValue(CurrentPowerOfTwoMode) == FPropertyAccess::Success);
		TextComboBox->SetSelectedItem(PowerOfTwoModeComboBoxList[CurrentPowerOfTwoMode]);
		return;
	}

	int32 PowerOfTwoMode = PowerOfTwoModeComboBoxList.Find(NewValue);
	check(PowerOfTwoMode != INDEX_NONE);
	ensure(PowerOfTwoModePropertyHandle->SetValue(static_cast<uint8>(PowerOfTwoMode)) == FPropertyAccess::Success);
}

#undef LOCTEXT_NAMESPACE