//  
// Copyright (c) 2023 articy Software GmbH & Co. KG. All rights reserved.  
//

#include "Slate/SArticyRefProperty.h"
#include <Templates/SharedPointer.h>
#include <Kismet2/KismetEditorUtilities.h>
#include <Kismet2/SClassPickerDialog.h>
#include "ArticyObject.h"
#include "ArticyEditorModule.h"
#include "ArticyEditorStyle.h"
#include "Slate/AssetPicker/SArticyObjectAssetPicker.h"
#include "Slate/UserInterfaceHelperFunctions.h"
#include "Framework/MultiBox/MultiBoxBuilder.h"
#include "HAL/PlatformApplicationMisc.h"
#include "Widgets/Input/SNumericEntryBox.h"
#include "Widgets/Input/SCheckBox.h"
#include "Widgets/Layout/SSpacer.h"

#define LOCTEXT_NAMESPACE "ArticyRefProperty"

/**
 * Constructs the SArticyRefProperty widget with the specified arguments.
 *
 * @param InArgs The declaration data for constructing the widget.
 */
void SArticyRefProperty::Construct(const FArguments& InArgs)
{
	if (ArticyRefToDisplay.IsBound())
	{
		ensureMsgf(InArgs._OnArticyRefChanged.IsBound(), TEXT("Since the shown object is given externally per event, the handler also needs to handle updates."));
	}

	this->ArticyRefToDisplay = InArgs._ArticyRefToDisplay;
	this->OnArticyRefChanged = InArgs._OnArticyRefChanged;
	this->TopLevelClassRestriction = InArgs._TopLevelClassRestriction;
	this->bExactClass = InArgs._bExactClass;
	this->bExactClassEditable = InArgs._bExactClassEditable;
	this->bIsReadOnly = InArgs._bIsReadOnly;

	SetCursor(EMouseCursor::Hand);

	CreateInternalWidgets();

	UpdateWidget();

	this->ChildSlot
		[
			ArticyIdProperty.ToSharedRef()
		];
}

/**
 * Updates the widget state on each tick.
 *
 * @param AllottedGeometry The geometry allocated for this widget.
 * @param InCurrentTime The current time.
 * @param InDeltaTime The time elapsed since the last tick.
 */
void SArticyRefProperty::Tick(const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime)
{
	const FArticyRef& CurrentRef = ArticyRefToDisplay.IsBound() || ArticyRefToDisplay.IsSet() ? ArticyRefToDisplay.Get() : FArticyRef();
	if (CurrentRef != CachedArticyRef || (!CurrentRef.GetId().IsNull() && !CachedArticyObject.IsValid()))
	{
		Update(CurrentRef);
	}
}

/**
 * Creates the internal widgets used within the ArticyRefProperty.
 */
void SArticyRefProperty::CreateInternalWidgets()
{
	FUIAction CopyAction;
	FUIAction PasteAction;

	CopyAction.ExecuteAction = FExecuteAction::CreateSP(this, &SArticyRefProperty::OnCopyProperty);
	PasteAction.CanExecuteAction = FCanExecuteAction::CreateSP(this, &SArticyRefProperty::CanPasteProperty);
	PasteAction.ExecuteAction = FExecuteAction::CreateSP(this, &SArticyRefProperty::OnPasteProperty);

	ArticyIdExtender = MakeShared<FExtender>();
	ArticyIdExtender->AddToolBarExtension("Base", EExtensionHook::After, nullptr, FToolBarExtensionDelegate::CreateSP(this, &SArticyRefProperty::CreateAdditionalRefWidgets));

	FOnArticyIdChanged OnArticyIdChanged = FOnArticyIdChanged::CreateSP(this, &SArticyRefProperty::OnArticyIdChanged);
	TAttribute<FArticyId> ArticyIdToDisplay;
	ArticyIdToDisplay.BindRaw(this, &SArticyRefProperty::GetArticyIdToDisplay);

	ArticyIdProperty = SNew(SArticyIdProperty)
		.ArticyIdToDisplay(ArticyIdToDisplay)
		.OnArticyIdChanged(OnArticyIdChanged)
		.TopLevelClassRestriction(TopLevelClassRestriction)
		.HighExtender(ArticyIdExtender)
		.bExactClass(bExactClass)
		.bExactClassEditable(bExactClassEditable)
		.bIsReadOnly(bIsReadOnly)
		.CopyAction(CopyAction)
		.PasteAction(PasteAction);
}

/**
 * Handles changes to the Articy ID.
 *
 * @param ArticyId The new Articy ID value.
 */
void SArticyRefProperty::OnArticyIdChanged(const FArticyId& ArticyId)
{
	// kind of redundant
	CachedArticyRef.SetId(ArticyId);
	OnArticyRefChanged.ExecuteIfBound(CachedArticyRef);
}

/**
 * Retrieves the Articy ID to be displayed.
 *
 * @return The Articy ID to display.
 */
FArticyId SArticyRefProperty::GetArticyIdToDisplay() const
{
	return ArticyRefToDisplay.Get().GetId();
}

/**
 * Creates additional reference widgets for the toolbar.
 *
 * @param Builder The toolbar builder to add widgets to.
 */
void SArticyRefProperty::CreateAdditionalRefWidgets(FToolBarBuilder& Builder)
{
	TSharedRef<SHorizontalBox> AdditionalWidgetBox = SNew(SHorizontalBox)
#if __cplusplus >= 202002L
		.IsEnabled_Lambda([=, this]()
#else
			.IsEnabled_Lambda([=]()
#endif
				{
					return !bIsReadOnly.Get();
				})
			+ SHorizontalBox::Slot()
					.HAlign(HAlign_Center)
					.VAlign(VAlign_Center)
					.Padding(1.f, 3.f)
					.AutoWidth()
					[
						SNew(STextBlock)
							.Text(FText::FromString("Base"))
							.TextStyle(&FArticyEditorStyle::Get().GetWidgetStyle<FTextBlockStyle>("ArticyImporter.SmallTextBlock"))
							.ToolTipText(FText::FromString("Should this ArticyRef reference the base object or a clone?"))
					]
					+ SHorizontalBox::Slot()
					.HAlign(HAlign_Center)
					.VAlign(VAlign_Center)
					.Padding(1.f, 3.f)
					.AutoWidth()
					[
						SNew(SCheckBox)
#if __cplusplus >= 202002L
							.IsChecked_Lambda([=, this]()
#else
								.IsChecked_Lambda([=]()
#endif
									{
										return CachedArticyRef.bReferenceBaseObject ? ECheckBoxState::Checked : ECheckBoxState::Unchecked;
									})
#if __cplusplus >= 202002L
								.OnCheckStateChanged_Lambda([=, this](ECheckBoxState NewState)
#else
									.OnCheckStateChanged_Lambda([=](ECheckBoxState NewState)
#endif
										{
											CachedArticyRef.bReferenceBaseObject = NewState == ECheckBoxState::Checked;
											OnArticyRefChanged.ExecuteIfBound(CachedArticyRef);
										})
					]
									+ SHorizontalBox::Slot()
									.HAlign(HAlign_Center)
									.VAlign(VAlign_Center)
									.FillWidth(1.f)
									[
										SNew(SSpacer)
									]
									+ SHorizontalBox::Slot()
									.HAlign(HAlign_Center)
									.VAlign(VAlign_Center)
									.Padding(1.f, 3.f)
									.AutoWidth()
									[
										SNew(STextBlock)
											.Text(FText::FromString("Clone"))
											.TextStyle(&FArticyEditorStyle::Get().GetWidgetStyle<FTextBlockStyle>("ArticyImporter.SmallTextBlock"))
											.ToolTipText(FText::FromString("Which clone Id should be referenced?"))
#if __cplusplus >= 202002L
											.Visibility_Lambda([=, this]()
#else
												.Visibility_Lambda([=]()
#endif
													{
														return CachedArticyRef.bReferenceBaseObject ? EVisibility::Collapsed : EVisibility::Visible;
													})
									]
												+ SHorizontalBox::Slot()
												.HAlign(HAlign_Center)
												.VAlign(VAlign_Center)
												.Padding(1.f, 0.f)
												.AutoWidth()
												[
													SNew(SNumericEntryBox<int32>)
														.MinDesiredValueWidth(15.f)
#if __cplusplus >= 202002L
														.Value_Lambda([=, this]()
#else
															.Value_Lambda([=]()
#endif
																{
																	return CachedArticyRef.CloneId;
																})
#if __cplusplus >= 202002L
															.OnValueChanged_Lambda([=, this](int32 NewValue)
#else
																.OnValueChanged_Lambda([=](int32 NewValue)
#endif
																	{
																		CachedArticyRef.CloneId = NewValue;
																		OnArticyRefChanged.ExecuteIfBound(CachedArticyRef);
																	})
#if __cplusplus >= 202002L
																.Visibility_Lambda([=, this]()
#else
																	.Visibility_Lambda([=]()
#endif
																		{
																			return CachedArticyRef.bReferenceBaseObject ? EVisibility::Collapsed : EVisibility::Visible;
																		})
												];

				Builder.AddWidget(AdditionalWidgetBox);
}

/**
 * Updates the ArticyRef with a new reference.
 *
 * @param NewRef The new ArticyRef to update.
 */
void SArticyRefProperty::Update(const FArticyRef& NewRef)
{
	CachedArticyRef = NewRef;
	CachedArticyObject = !CachedArticyRef.GetId().IsNull() ? UArticyObject::FindAsset(CachedArticyRef.GetId()) : nullptr;

	UpdateWidget();
}

/**
 * Updates the widget display and customizations.
 */
void SArticyRefProperty::UpdateWidget()
{
	// not yet done
}

/**
 * Copies the property value to the clipboard.
 */
void SArticyRefProperty::OnCopyProperty() const
{
	FString ValueString = CachedArticyRef.ToString();
	FPlatformApplicationMisc::ClipboardCopy(*ValueString);
}

/**
 * Pastes the property value from the clipboard.
 */
void SArticyRefProperty::OnPasteProperty()
{
	FString ClipboardContent;
	FPlatformApplicationMisc::ClipboardPaste(ClipboardContent);

	// copies over all values, then initializes with the string content. This makes both Ids and Refs pastable without deleting data
	FArticyRef NewRef = CachedArticyRef;
	const FArticyRef::EStringInitResult Success = NewRef.InitFromString(ClipboardContent);
	if (ensureMsgf(Success != FArticyRef::NoneSet, TEXT("String was garbage, therefore Ref was not properly updated")))
	{
		OnArticyRefChanged.ExecuteIfBound(NewRef);
		Update(NewRef);
	}
}

/**
 * Determines whether the property can be pasted.
 *
 * @return true if the property can be pasted, false otherwise.
 */
bool SArticyRefProperty::CanPasteProperty() const
{
	if (bIsReadOnly.Get())
	{
		return false;
	}

	FString ClipboardContent;
	FPlatformApplicationMisc::ClipboardPaste(ClipboardContent);

	if (ClipboardContent.IsEmpty() || !ClipboardContent.Contains("Low=") || !ClipboardContent.Contains("High="))
	{
		return false;
	}

	FArticyId CandidateId;
	if (CandidateId.InitFromString(ClipboardContent))
	{
		UArticyObject* Object = UArticyObject::FindAsset(CandidateId);
		if (!Object)
		{
			return false;
		}

		return Object->UObject::GetClass()->IsChildOf(TopLevelClassRestriction.Get());
	}

	return false;
}
#undef LOCTEXT_NAMESPACE