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

#pragma once

#include "CoreMinimal.h"
#include "Fonts/SlateFontInfo.h"

// Insights
#include "Insights/ViewModels/BaseTimingTrack.h"
#include "Insights/ViewModels/TrackHeader.h"

namespace Trace
{
struct FLogMessage;
class ILogProvider;
}  // namespace Trace

struct FDrawContext;
struct FSlateBrush;
class FTimingTrackViewport;

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

struct FTimeMarkerBoxInfo
{
    float X;
    float W;
    FLinearColor Color;
};

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

struct FTimeMarkerTextInfo
{
    float X;
    FLinearColor Color;
    FString Category;  // truncated Category string
    FString Message;   // truncated Message string
};

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

class FMarkersTimingTrack: public FBaseTimingTrack
{
    friend class FTimeMarkerTrackBuilder;

    INSIGHTS_DECLARE_RTTI(FMarkersTimingTrack, FBaseTimingTrack)

public:
    FMarkersTimingTrack();
    virtual ~FMarkersTimingTrack();

    virtual void Reset() override;

    bool IsCollapsed() const { return Header.IsCollapsed(); }
    void Expand() { Header.SetIsCollapsed(false); }
    void Collapse() { Header.SetIsCollapsed(true); }
    void ToggleCollapsed() { Header.ToggleCollapsed(); }

    bool IsBookmarksTrack() const { return bUseOnlyBookmarks; }
    bool IsLogsTrack() const { return !bUseOnlyBookmarks; }
    void SetBookmarksTrackFlag(bool bInUseOnlyBookmarks)
    {
        bUseOnlyBookmarks = bInUseOnlyBookmarks;
        UpdateTrackNameAndHeight();
    }
    void SetBookmarksTrack() { SetBookmarksTrackFlag(true); }
    void SetLogsTrack() { SetBookmarksTrackFlag(false); }

    // Stats
    int32 GetNumLogMessages() const { return NumLogMessages; }
    int32 GetNumBoxes() const { return TimeMarkerBoxes.Num(); }
    int32 GetNumTexts() const { return TimeMarkerTexts.Num(); }

    // FBaseTimingTrack
    virtual void Update(const ITimingTrackUpdateContext& Context) override;
    virtual void PostUpdate(const ITimingTrackUpdateContext& Context) override;
    virtual void Draw(const ITimingTrackDrawContext& Context) const override;
    virtual void PostDraw(const ITimingTrackDrawContext& Context) const override;
    virtual FReply OnMouseButtonDown(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    virtual FReply OnMouseButtonDoubleClick(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    virtual void BuildContextMenu(FMenuBuilder& MenuBuilder) override;

private:
    void ResetCache()
    {
        TimeMarkerBoxes.Reset();
        TimeMarkerTexts.Reset();
    }

    void UpdateTrackNameAndHeight();
    void UpdateDrawState(const FTimingTrackViewport& Viewport);

private:
    TArray<FTimeMarkerBoxInfo> TimeMarkerBoxes;
    TArray<FTimeMarkerTextInfo> TimeMarkerTexts;

    bool bUseOnlyBookmarks;  // If true, uses only bookmarks; otherwise it uses all log messages.

    FTrackHeader Header;

    // Stats
    int32 NumLogMessages;
    mutable int32 NumDrawBoxes;
    mutable int32 NumDrawTexts;

    // Slate resources
    const FSlateBrush* WhiteBrush;
    const FSlateFontInfo Font;
};

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

class FTimeMarkerTrackBuilder
{
public:
    explicit FTimeMarkerTrackBuilder(FMarkersTimingTrack& InTrack, const FTimingTrackViewport& InViewport);

    /**
     * Non-copyable
     */
    FTimeMarkerTrackBuilder(const FTimeMarkerTrackBuilder&)            = delete;
    FTimeMarkerTrackBuilder& operator=(const FTimeMarkerTrackBuilder&) = delete;

    const FTimingTrackViewport& GetViewport() { return Viewport; }

    void BeginLog(const Trace::ILogProvider& LogProvider);
    void AddLogMessage(const Trace::FLogMessage& Message);
    void EndLog();

    static FLinearColor GetColorByCategory(const TCHAR* const Category);
    static FLinearColor GetColorByVerbosity(const ELogVerbosity::Type Verbosity);

private:
    void Flush(float AvailableTextW);
    void AddTimeMarker(const float X, const uint64 LogIndex, const ELogVerbosity::Type Verbosity, const TCHAR* const Category, const TCHAR* Message);

private:
    FMarkersTimingTrack& Track;
    const FTimingTrackViewport& Viewport;

    const TSharedRef<class FSlateFontMeasure> FontMeasureService;
    const FSlateFontInfo Font;

    const Trace::ILogProvider* LogProviderPtr;  // valid only between BeginLog() and EndLog()

    float LastX1;
    float LastX2;
    uint64 LastLogIndex;
    ELogVerbosity::Type LastVerbosity;
    const TCHAR* LastCategory;
    const TCHAR* LastMessage;
};

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