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

#pragma once

#include "CoreMinimal.h"
#include "Types/SlateEnums.h"
#include "Misc/EnumClassFlags.h"

#include "Insights/Table/ViewModels/TableCellValue.h"

namespace Insights
{

class FBaseTreeNode;
class FTable;
class ITableCellValueGetter;
class ITableCellValueFormatter;
class ITableCellValueSorter;

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

enum class ETableColumnFlags : uint32
{
    None            = 0,

    ShouldBeVisible = (1 << 0),
    CanBeHidden     = (1 << 1),
    CanBeFiltered   = (1 << 2),
    IsHierarchy     = (1 << 3),
};
ENUM_CLASS_FLAGS(ETableColumnFlags);

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

enum class ETableColumnAggregation : uint32
{
    None = 0,
    Sum,
    // Min,
    // Max,
    // Average,
    // Median,
};

////////////////////////////////////////////////////////////////////////////////////////////////////
/**
 * Table Column View Model.
 * Holds information about a column in STableListView or STableTreeView widgets.
 */
class FTableColumn
{
public:
    /** No default constructor. */
    FTableColumn() = delete;

    /** Initialization constructor. */
    FTableColumn(const FName InId)
        : Id(InId), Order(0), Index(-1), ShortName(), TitleName(), Description(), bIsVisible(false), Flags(ETableColumnFlags::None), HorizontalAlignment(HAlign_Left), InitialWidth(60.0f), MinWidth(0.0f), MaxWidth(FLT_MAX), DataType(ETableCellDataType::Unknown), Aggregation(ETableColumnAggregation::None), ValueGetter(GetDefaultValueGetter()), ValueFormatter(GetDefaultValueFormatter()), ValueSorter(nullptr), ParentTable(nullptr)
    {
    }

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

    const FName& GetId() const { return Id; }

    int32 GetIndex() const { return Index; }
    void SetIndex(int32 InIndex) { Index = InIndex; }

    //////////////////////////////////////////////////
    // Name and Description

    const FText& GetShortName() const { return ShortName; }
    void SetShortName(const FText& InShortName) { ShortName = InShortName; }

    const FText& GetTitleName() const { return TitleName; }
    void SetTitleName(const FText& InTitleName) { TitleName = InTitleName; }

    const FText& GetDescription() const { return Description; }
    void SetDescription(const FText& InDescription) { Description = InDescription; }

    //////////////////////////////////////////////////
    // Visibility and other Flags

    bool IsVisible() const { return bIsVisible; }
    void Show()
    {
        bIsVisible = true;
        OnVisibilityChanged();
    }
    void Hide()
    {
        bIsVisible = false;
        OnVisibilityChanged();
    }
    void ToggleVisibility()
    {
        bIsVisible = !bIsVisible;
        OnVisibilityChanged();
    }
    void SetVisibilityFlag(bool bOnOff)
    {
        bIsVisible = bOnOff;
        OnVisibilityChanged();
    }
    /*virtual*/ void OnVisibilityChanged() {}

    /** Whether this column should be initially visible. */
    bool ShouldBeVisible() const { return EnumHasAnyFlags(Flags, ETableColumnFlags::ShouldBeVisible); }

    /** Whether this column can be hidden. */
    bool CanBeHidden() const { return EnumHasAnyFlags(Flags, ETableColumnFlags::CanBeHidden); }

    /** Whether this column can be used for filtering displayed results. */
    bool CanBeFiltered() const { return EnumHasAnyFlags(Flags, ETableColumnFlags::CanBeFiltered); }

    /** Whether this column is the hierarcy (name) column, in a tree view. */
    bool IsHierarchy() const { return EnumHasAnyFlags(Flags, ETableColumnFlags::IsHierarchy); }

    void SetFlags(ETableColumnFlags InFlags) { Flags = InFlags; }

    //////////////////////////////////////////////////
    // Alignment and Width

    EHorizontalAlignment GetHorizontalAlignment() const { return HorizontalAlignment; }
    void SetHorizontalAlignment(EHorizontalAlignment InHorizontalAlignment) { HorizontalAlignment = InHorizontalAlignment; }

    float GetInitialWidth() const { return InitialWidth; }
    void SetInitialWidth(float InWidth) { InitialWidth = InWidth; }

    float GetMinWidth() const { return MinWidth; }
    void SetMinWidth(float InWidth) { MinWidth = InWidth; }

    float GetMaxWidth() const { return MaxWidth; }
    void SetMaxWidth(float InWidth) { MaxWidth = InWidth; }

    // float GetWidth() const { return Width; }
    // void SetWidth(float InWidth) { Width = InWidth; }

    /** If MinWidth == MaxWidth, this column has fixed width and cannot be resized. */
    bool IsFixedWidth() const { return MinWidth == MaxWidth; }

    //////////////////////////////////////////////////
    // Data Type

    ETableCellDataType GetDataType() const { return DataType; }
    void SetDataType(ETableCellDataType InDataType) { DataType = InDataType; }

    //////////////////////////////////////////////////
    // Aggregation

    ETableColumnAggregation GetAggregation() const { return Aggregation; }
    void SetAggregation(ETableColumnAggregation InAggregation) { Aggregation = InAggregation; }

    //////////////////////////////////////////////////
    // Value Getter

    static TSharedRef<ITableCellValueGetter> GetDefaultValueGetter();

    TSharedRef<ITableCellValueGetter> GetValueGetter() const { return ValueGetter; }
    void SetValueGetter(TSharedRef<ITableCellValueGetter> InValueGetter) { ValueGetter = InValueGetter; }

    const TOptional<FTableCellValue> GetValue(const FBaseTreeNode& InNode) const;

    //////////////////////////////////////////////////
    // Value Formatter

    static TSharedRef<ITableCellValueFormatter> GetDefaultValueFormatter();

    TSharedRef<ITableCellValueFormatter> GetValueFormatter() const { return ValueFormatter; }
    void SetValueFormatter(TSharedRef<ITableCellValueFormatter> InValueFormatter) { ValueFormatter = InValueFormatter; }

    FText GetValueAsText(const FBaseTreeNode& InNode) const;
    FText GetValueAsTooltipText(const FBaseTreeNode& InNode) const;

    //////////////////////////////////////////////////
    // Value Sorter (can be nullptr)

    TSharedPtr<ITableCellValueSorter> GetValueSorter() const { return ValueSorter; }
    void SetValueSorter(TSharedPtr<ITableCellValueSorter> InValueSorter) { ValueSorter = InValueSorter; }

    /** Whether this column can be used for sorting. */
    bool CanBeSorted() const { return ValueSorter.IsValid(); }

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

    TWeakPtr<FTable> GetParentTable() const { return ParentTable; }
    void SetParentTable(TWeakPtr<FTable> InParentTable) { ParentTable = InParentTable; }

private:
    /** Id of the column. */
    FName Id;

    /** Order value, to sort columns in the list/tree view. */
    int32 Order;

    /** Column index in source table. */
    int32 Index;

    /** Short name of the column, displayed in the column header. */
    FText ShortName;

    /** Title name of the column, displayed as title in the column tooltip. */
    FText TitleName;

    /** Long name of the column, displayed in the column tooltip. */
    FText Description;

    /** Is this column visible? */
    bool bIsVisible;

    /** Other on/off switches. */
    ETableColumnFlags Flags;

    /** Horizontal alignment of the content in this column. */
    EHorizontalAlignment HorizontalAlignment;

    float InitialWidth; /**< Initial column width. */
    float MinWidth;     /**< Minimum column width. */
    float MaxWidth;     /**< Maximum column width. */
    // float Width; /**< Current column width. */

    /** Data type for this column. */
    ETableCellDataType DataType;

    /** Aggregation for values in this column, when grouped. */
    ETableColumnAggregation Aggregation;  // TODO: make this an object (Aggregator)

    /** Custom getter for values identified by this column. */
    TSharedRef<ITableCellValueGetter> ValueGetter;

    /** Custom formater for values displayed by this column. */
    TSharedRef<ITableCellValueFormatter> ValueFormatter;

    /** Custom sorter for values displayed by this column. */
    TSharedPtr<ITableCellValueSorter> ValueSorter;

    /* Parent table. Only one table instance can own this column. */
    TWeakPtr<FTable> ParentTable;
};

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

}  // namespace Insights