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

#include "SViewportToolBarIconMenu.h"
#include "Widgets/SBoxPanel.h"
#include "Widgets/Images/SImage.h"
#include "Widgets/Text/STextBlock.h"
#include "Widgets/Layout/SBox.h"
#include "Widgets/Input/SMenuAnchor.h"
#include "Widgets/Input/SButton.h"
#include "EditorStyleSet.h"

void SViewportToolBarIconMenu::Construct(const FArguments& InArgs)
{
    ParentToolBar           = InArgs._ParentToolBar;

    const FName ButtonStyle = FEditorStyle::Join(InArgs._Style.Get(), ".Button");

    const FSlateIcon& Icon  = InArgs._Icon.Get();

    SAssignNew(MenuAnchor, SMenuAnchor)
        .Placement(MenuPlacement_BelowAnchor)
        .OnGetMenuContent(InArgs._OnGetMenuContent)
            [SNew(SButton)
                 .ButtonStyle(FEditorStyle::Get(), ButtonStyle)
                 .ContentPadding(FMargin(5.0f, 0.0f))
                 .OnClicked(this, &SViewportToolBarIconMenu::OnMenuClicked)
                     [SNew(SHorizontalBox)

                      // Icon
                      + SHorizontalBox::Slot()
                            .AutoWidth()
                                [SNew(SBox)
                                     .WidthOverride(16)
                                     .HeightOverride(16)
                                     .HAlign(HAlign_Center)
                                     .VAlign(VAlign_Center)
                                         [SNew(SImage)
                                              .Image(Icon.GetIcon())]]

                      // Spacer
                      + SHorizontalBox::Slot()
                            .AutoWidth()
                            .Padding(FMargin(4.0f, 0.0f))

                      // Menu dropdown
                      + SHorizontalBox::Slot()
                            .AutoWidth()
                                [SNew(SVerticalBox) + SVerticalBox::Slot().AutoHeight().HAlign(HAlign_Center).VAlign(VAlign_Top)[SNew(STextBlock).TextStyle(FEditorStyle::Get(), FEditorStyle::Join(InArgs._Style.Get(), ".Label")).Text(InArgs._Label)] + SVerticalBox::Slot().AutoHeight().VAlign(VAlign_Bottom)[SNew(SHorizontalBox) + SHorizontalBox::Slot().FillWidth(1.0f)

                                                                                                                                                                                                                                                                                                                   + SHorizontalBox::Slot().AutoWidth()[SNew(SBox).WidthOverride(4).HeightOverride(4)[SNew(SImage).Image(FEditorStyle::GetBrush("ComboButton.Arrow")).ColorAndOpacity(FLinearColor::Black)]]

                                                                                                                                                                                                                                                                                                                   + SHorizontalBox::Slot().FillWidth(1.0f)]]]];

    ChildSlot
        [MenuAnchor.ToSharedRef()];
}

FReply SViewportToolBarIconMenu::OnMenuClicked()
{
    // If the menu button is clicked toggle the state of the menu anchor which will open or close the menu
    MenuAnchor->SetIsOpen(!MenuAnchor->IsOpen());
    ParentToolBar.Pin()->SetOpenMenu(MenuAnchor);
    return FReply::Handled();
}

void SViewportToolBarIconMenu::OnMouseEnter(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent)
{
    // See if there is another menu on the same tool bar already open
    TWeakPtr<SMenuAnchor> OpenedMenu = ParentToolBar.Pin()->GetOpenMenu();
    if (OpenedMenu.IsValid() && OpenedMenu.Pin()->IsOpen() && OpenedMenu.Pin() != MenuAnchor)
    {
        // There is another menu open so we open this menu and close the other
        ParentToolBar.Pin()->SetOpenMenu(MenuAnchor);
        MenuAnchor->SetIsOpen(true);
    }
}