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

#pragma once

#include "CoreMinimal.h"
#include "SlateFwd.h"
#include "TraceServices/Model/TimingProfiler.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Widgets/SCompoundWidget.h"
#include "Widgets/SWidget.h"
#include "Widgets/Views/SHeaderRow.h"
#include "Widgets/Views/STableRow.h"
#include "Widgets/Views/STableViewBase.h"
#include "Widgets/Views/STreeView.h"

// Insights
#include "Insights/ViewModels/TimerGroupingAndSorting.h"
#include "Insights/ViewModels/TimerNode.h"

////////////////////////////////////////////////////////////////////////////////////////////////////

class FMenuBuilder;
class FUICommandList;

namespace Insights
{
class FTable;
class FTableColumn;
class ITableCellValueSorter;
class SAggregatorStatus;
}  // namespace Insights

////////////////////////////////////////////////////////////////////////////////////////////////////

/**
 * A custom widget used to display the timers in a tree view (ex. Callers and Callees).
 */
class STimerTreeView: public SCompoundWidget
{
public:
    /** Default constructor. */
    STimerTreeView();

    /** Virtual destructor. */
    virtual ~STimerTreeView();

    SLATE_BEGIN_ARGS(STimerTreeView) {}
    SLATE_END_ARGS()

    /**
     * Construct this widget
     * @param InArgs - The declaration data for this widget
     */
    void Construct(const FArguments& InArgs, const FText& InViewName);

    void Reset();
    void SetTree(const Trace::FTimingProfilerButterflyNode& Root);

    virtual FReply OnKeyDown(const FGeometry& MyGeometry, const FKeyEvent& InKeyEvent) override;

private:
    void InitCommandList();
    FTimerNodePtr CreateTimerNodeRec(const Trace::FTimingProfilerButterflyNode& Node);
    void ExpandNodesRec(FTimerNodePtr NodePtr, int32 Depth);

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Tree View - Context Menu

    TSharedPtr<SWidget> TreeView_GetMenuContent();
    void TreeView_BuildSortByMenu(FMenuBuilder& MenuBuilder);
    void TreeView_BuildViewColumnMenu(FMenuBuilder& MenuBuilder);

    bool ContextMenu_CopySelectedToClipboard_CanExecute() const;
    void ContextMenu_CopySelectedToClipboard_Execute();

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Tree View - Columns' Header

    void InitializeAndShowHeaderColumns();

    FText GetColumnHeaderText(const FName ColumnId) const;

    TSharedRef<SWidget> TreeViewHeaderRow_GenerateColumnMenu(const Insights::FTableColumn& Column);

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Tree View - Misc

    void TreeView_Refresh();

    /**
     * Called by STreeView to retrieves the children for the specified parent item.
     * @param InParent    - The parent node to retrieve the children from.
     * @param OutChildren - List of children for the parent node.
     */
    void TreeView_OnGetChildren(FTimerNodePtr InParent, TArray<FTimerNodePtr>& OutChildren);

    /** Called by STreeView when selection has changed. */
    void TreeView_OnSelectionChanged(FTimerNodePtr SelectedItem, ESelectInfo::Type SelectInfo);

    /** Called by STreeView when a tree item is double clicked. */
    void TreeView_OnMouseButtonDoubleClick(FTimerNodePtr TreeNode);

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Tree View - Table Row

    /** Called by STreeView to generate a table row for the specified item. */
    TSharedRef<ITableRow> TreeView_OnGenerateRow(FTimerNodePtr TreeNode, const TSharedRef<STableViewBase>& OwnerTable);

    bool TableRow_ShouldBeEnabled(FTimerNodePtr NodePtr) const;

    void TableRow_SetHoveredCell(TSharedPtr<Insights::FTable> TablePtr, TSharedPtr<Insights::FTableColumn> ColumnPtr, FTimerNodePtr NodePtr);
    EHorizontalAlignment TableRow_GetColumnOutlineHAlignment(const FName ColumnId) const;

    FText TableRow_GetHighlightText() const;
    FName TableRow_GetHighlightedNodeName() const;

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Sorting

    static const FName GetDefaultColumnBeingSorted();
    static const EColumnSortMode::Type GetDefaultColumnSortMode();

    void CreateSortings();

    void UpdateCurrentSortingByColumn();
    void SortTreeNodes();
    void SortTreeNodesRec(FTimerNode& Node, const Insights::ITableCellValueSorter& Sorter);

    EColumnSortMode::Type GetSortModeForColumn(const FName ColumnId) const;
    void SetSortModeForColumn(const FName& ColumnId, EColumnSortMode::Type SortMode);
    void OnSortModeChanged(const EColumnSortPriority::Type SortPriority, const FName& ColumnId, const EColumnSortMode::Type SortMode);

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Sorting actions

    // SortMode (HeaderMenu)
    bool HeaderMenu_SortMode_IsChecked(const FName ColumnId, const EColumnSortMode::Type InSortMode);
    bool HeaderMenu_SortMode_CanExecute(const FName ColumnId, const EColumnSortMode::Type InSortMode) const;
    void HeaderMenu_SortMode_Execute(const FName ColumnId, const EColumnSortMode::Type InSortMode);

    // SortMode (ContextMenu)
    bool ContextMenu_SortMode_IsChecked(const EColumnSortMode::Type InSortMode);
    bool ContextMenu_SortMode_CanExecute(const EColumnSortMode::Type InSortMode) const;
    void ContextMenu_SortMode_Execute(const EColumnSortMode::Type InSortMode);

    // SortByColumn (ContextMenu)
    bool ContextMenu_SortByColumn_IsChecked(const FName ColumnId);
    bool ContextMenu_SortByColumn_CanExecute(const FName ColumnId) const;
    void ContextMenu_SortByColumn_Execute(const FName ColumnId);

    ////////////////////////////////////////////////////////////////////////////////////////////////////
    // Column visibility actions

    // ShowColumn
    bool CanShowColumn(const FName ColumnId) const;
    void ShowColumn(const FName ColumnId);

    // HideColumn
    bool CanHideColumn(const FName ColumnId) const;
    void HideColumn(const FName ColumnId);

    // ToggleColumnVisibility
    bool IsColumnVisible(const FName ColumnId);
    bool CanToggleColumnVisibility(const FName ColumnId) const;
    void ToggleColumnVisibility(const FName ColumnId);

    // ShowAllColumns (ContextMenu)
    bool ContextMenu_ShowAllColumns_CanExecute() const;
    void ContextMenu_ShowAllColumns_Execute();

    // ResetColumns (ContextMenu)
    bool ContextMenu_ResetColumns_CanExecute() const;
    void ContextMenu_ResetColumns_Execute();

    ////////////////////////////////////////////////////////////////////////////////////////////////////

private:
    /** Table view model. */
    TSharedPtr<Insights::FTable> Table;

    /** The view name (ex.: "Callers" or "Callees"). */
    FText ViewName;

    TSharedPtr<FUICommandList> CommandList;

    //////////////////////////////////////////////////
    // Tree View, Columns

    /** The tree widget which holds the list of groups and timers corresponding with each group. */
    TSharedPtr<STreeView<FTimerNodePtr>> TreeView;

    /** Holds the tree view header row widget which display all columns in the tree view. */
    TSharedPtr<SHeaderRow> TreeViewHeaderRow;

    /** External scrollbar used to synchronize tree view position. */
    TSharedPtr<SScrollBar> ExternalScrollbar;

    //////////////////////////////////////////////////
    // Hovered Column, Hovered Timer Node

    /** Name of the column currently being hovered by the mouse. */
    FName HoveredColumnId;

    /** A shared pointer to the timer node currently being hovered by the mouse. */
    FTimerNodePtr HoveredNodePtr;

    /** Name of the timer that should be drawn as highlighted. */
    FName HighlightedNodeName;

    //////////////////////////////////////////////////
    // Timer Nodes

    /** The root node(s) of the tree. */
    TArray<FTimerNodePtr> TreeNodes;

    //////////////////////////////////////////////////
    // Sorting

    /** All available sorters. */
    TArray<TSharedPtr<Insights::ITableCellValueSorter>> AvailableSorters;

    /** Current sorter. It is nullptr if sorting is disabled. */
    TSharedPtr<Insights::ITableCellValueSorter> CurrentSorter;

    /** Name of the column currently being sorted. Can be NAME_None if sorting is disabled (CurrentSorting == nullptr) or if a complex sorting is used (CurrentSorting != nullptr). */
    FName ColumnBeingSorted;

    /** How we sort the nodes? Ascending or Descending. */
    EColumnSortMode::Type ColumnSortMode;

    //////////////////////////////////////////////////

    double StatsStartTime;
    double StatsEndTime;
    uint32 StatsTimerId;

    TSharedPtr<Insights::SAggregatorStatus> AggregatorStatus;
};

////////////////////////////////////////////////////////////////////////////////////////////////////