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

#include "SEditorViewportToolBarMenu.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 SEditorViewportToolbarMenu::Construct(const FArguments& Declaration)
{
    const TAttribute<FText>& Label = Declaration._Label;

    const FName ImageName          = Declaration._Image;
    const FSlateBrush* ImageBrush  = FEditorStyle::GetBrush(ImageName);

    LabelIconBrush                 = Declaration._LabelIcon;

    ParentToolBar                  = Declaration._ParentToolBar;
    checkf(ParentToolBar.IsValid(), TEXT("The parent toolbar must be specified"));

    TSharedPtr<SWidget> ButtonContent;

    const float MenuIconSize = 16.0f;

    // Create the content for the button.  We always use an image over a label if it is valid
    if (ImageName != NAME_None)
    {
        ButtonContent =
            SNew(SBox)
                .HeightOverride(MenuIconSize)
                .VAlign(VAlign_Center)
                .HAlign(HAlign_Center)
                    [SNew(SImage)
                         .Image(ImageBrush)
                         .ColorAndOpacity(FSlateColor::UseForeground())];
    }
    else
    {
        if (LabelIconBrush.IsBound() || LabelIconBrush.Get() != NULL)
        {
            // Label with an icon to the left

            ButtonContent =
                SNew(SHorizontalBox) + SHorizontalBox::Slot().AutoWidth().Padding(0.0f, 0.0f, 3.0f, 0.0f)[SNew(SBox).Visibility(this, &SEditorViewportToolbarMenu::GetLabelIconVisibility).WidthOverride(MenuIconSize).HeightOverride(MenuIconSize).VAlign(VAlign_Center).HAlign(HAlign_Center)[SNew(SImage).Image(LabelIconBrush)]] + SHorizontalBox::Slot().FillWidth(1.0f).VAlign(VAlign_Center)[SNew(SBox).HeightOverride(MenuIconSize).VAlign(VAlign_Center)[SNew(STextBlock).Font(FEditorStyle::GetFontStyle("EditorViewportToolBar.Font")).Text(Label)]];
        }
        else
        {
            // Just the label text, no icon
            ButtonContent =
                SNew(SBox)
                    .HeightOverride(MenuIconSize)
                    .VAlign(VAlign_Center)
                        [SNew(STextBlock)
                             .Font(FEditorStyle::GetFontStyle("EditorViewportToolBar.Font"))
                             .Text(Label)];
        }
    }

    ChildSlot
        [SAssignNew(MenuAnchor, SMenuAnchor)
             .Placement(MenuPlacement_BelowAnchor)
                 [SNew(SButton)
                      // Allows users to drag with the mouse to select options after opening the menu */
                      .ClickMethod(EButtonClickMethod::MouseDown)
                      .ContentPadding(FMargin(5.0f, 2.0f))
                      .VAlign(VAlign_Center)
                      .ButtonStyle(Declaration._MenuStyle)
                      .OnClicked(this, &SEditorViewportToolbarMenu::OnMenuClicked)
                          [ButtonContent.ToSharedRef()]]
             .OnGetMenuContent(Declaration._OnGetMenuContent)];
}

FReply SEditorViewportToolbarMenu::OnMenuClicked()
{
    // If the menu button is clicked toggle the state of the menu anchor which will open or close the menu
    if (MenuAnchor->ShouldOpenDueToClick())
    {
        MenuAnchor->SetIsOpen(true);
        ParentToolBar.Pin()->SetOpenMenu(MenuAnchor);
    }
    else
    {
        MenuAnchor->SetIsOpen(false);
        TSharedPtr<SMenuAnchor> NullAnchor;
        ParentToolBar.Pin()->SetOpenMenu(NullAnchor);
    }

    return FReply::Handled();
}

void SEditorViewportToolbarMenu::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);
    }
}

EVisibility SEditorViewportToolbarMenu::GetLabelIconVisibility() const
{
    return LabelIconBrush.Get() != NULL ? EVisibility::Visible : EVisibility::Collapsed;
}

TWeakPtr<class SViewportToolBar> SEditorViewportToolbarMenu::GetParentToolBar() const
{
    return ParentToolBar;
}