// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreMinimal.h"
#include "Misc/Attribute.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Widgets/SCompoundWidget.h"
#include "Framework/SlateDelegates.h"
#include "Framework/Commands/UICommandInfo.h"
#include "Styling/SlateTypes.h"
#include "EditorStyleSet.h"
#include "Styling/SlateWidgetStyleAsset.h"

struct FSlateBrush;
enum class ECheckBoxState : uint8;

/**
 * A simple class that represents a toolbar button in an editor viewport toolbar
 */
class UNREALED_API SEditorViewportToolBarButton: public SCompoundWidget
{
public:
    SLATE_BEGIN_ARGS(SEditorViewportToolBarButton)
        : _ButtonType(EUserInterfaceActionType::Button), _ButtonStyle(&FEditorStyle::Get().GetWidgetStyle<FButtonStyle>("EditorViewportToolBar.Button")), _CheckBoxStyle(&FEditorStyle::Get().GetWidgetStyle<FCheckBoxStyle>("LevelViewportToolBar.CheckBoxButton")), _IsChecked(false)
    {}

    /** Called when the button is clicked */
    SLATE_EVENT(FOnClicked, OnClicked)

    /** The button type to use */
    SLATE_ARGUMENT(EUserInterfaceActionType, ButtonType)

    /** Style to use when this is a regular button type */
    SLATE_STYLE_ARGUMENT(FButtonStyle, ButtonStyle)

    /** Style to use when this is a check box type */
    SLATE_STYLE_ARGUMENT(FCheckBoxStyle, CheckBoxStyle)

    /** Checked state of the button */
    SLATE_ATTRIBUTE(bool, IsChecked)

    /** Style name of an image to use. Simple two state images are supported.  An image can be different depending on checked/unchecked state */
    SLATE_ATTRIBUTE(FName, Image)
    /** Any custom content to show in the button in place of other content */
    SLATE_DEFAULT_SLOT(FArguments, Content)
    SLATE_END_ARGS()

    void Construct(const FArguments& Declaration);

private:
    /**
     * Called when the button check state changes
     *
     * @param NewCheckedState	The new state of the check box
     */
    void OnCheckStateChanged(ECheckBoxState NewCheckedState);

    /**
     * Called when we need to get the image to show in the button
     *
     * @return The brush defining the image to use
     */
    const FSlateBrush* OnGetButtonImage() const;

    /**
     * Called when we need to get the state of the check box button
     *
     * @return The state of the check box button
     */
    ECheckBoxState OnIsChecked() const;

private:
    /** Attribute used to get the state of a checkbox */
    TAttribute<bool> IsChecked;
    /** Delegate to call when the button is clicked */
    FOnClicked OnClickedDelegate;
    /** Cached brush to use when the button is checked */
    const FSlateBrush* CheckedBrush;
    /** Cached brush to use when the button is unchecked */
    const FSlateBrush* NormalBrush;
};