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

#pragma once

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

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

struct FDrawContext;
struct FSlateBrush;
class FTimingTrackViewport;

namespace Insights
{

class ITimingViewExtender;

class FTimeMarker
{
public:
    FTimeMarker()
        : Time(0.0), Name(TEXT("T")), Color(FLinearColor(1.0f, 1.0f, 1.0f, 0.5f)), bIsVisible(true), bIsHighlighted(false), CrtTextWidth(0.0f)
    {}

    double GetTime() const { return Time; }
    void SetTime(const double InTime) { Time = InTime; }

    const FString& GetName() const { return Name; }
    void SetName(const FString& InName) { Name = InName; }

    const FLinearColor& GetColor() const { return Color; }
    void SetColor(const FLinearColor& InColor) { Color = InColor; }

    bool IsVisible() const { return bIsVisible; }
    void SetVisibility(bool bOnOff) { bIsVisible = bOnOff; }

    bool IsHighlighted() const { return bIsHighlighted; }
    void SetHighlighted(bool bOnOff) { bIsHighlighted = bOnOff; }

    float GetCrtTextWidth() const { return CrtTextWidth; }
    void SetCrtTextWidthAnimated(const float InTextWidth) const { CrtTextWidth = CrtTextWidth * 0.6f + InTextWidth * 0.4f; }

private:
    double Time;
    FString Name;
    FLinearColor Color;
    bool bIsVisible;
    bool bIsHighlighted;

    // Smoothed time marker text width to avoid flickering
    mutable float CrtTextWidth;
};

}  // namespace Insights

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

class FTimeRulerTrack: public FBaseTimingTrack
{
    INSIGHTS_DECLARE_RTTI(FTimeRulerTrack, FBaseTimingTrack)

public:
    FTimeRulerTrack();
    virtual ~FTimeRulerTrack();

    virtual void Reset() override;

    void SetSelection(const bool bInIsSelecting, const double InSelectionStartTime, const double InSelectionEndTime);

    void AddTimeMarker(TSharedRef<Insights::FTimeMarker> InTimeMarker);
    void RemoveTimeMarker(TSharedRef<Insights::FTimeMarker> InTimeMarker);

    TSharedPtr<Insights::FTimeMarker> GetTimeMarkerByName(const FString& InTimeMarkerName);
    TSharedPtr<Insights::FTimeMarker> GetTimeMarkerAtPos(const FVector2D& InPosition, const FTimingTrackViewport& InViewport);

    bool IsScrubbing() const { return bIsScrubbing; }
    TSharedRef<Insights::FTimeMarker> GetScrubbingTimeMarker() { return TimeMarkers.Last(); }
    void StartScrubbing(TSharedRef<Insights::FTimeMarker> InTimeMarker);
    void StopScrubbing();

    virtual void PostUpdate(const ITimingTrackUpdateContext& Context) override;
    void Draw(const ITimingTrackDrawContext& Context) const override;
    void PostDraw(const ITimingTrackDrawContext& Context) const override;

private:
    void DrawTimeMarker(const ITimingTrackDrawContext& Context, const Insights::FTimeMarker& TimeMarker) const;

public:
    // Slate resources
    const FSlateBrush* WhiteBrush;
    const FSlateFontInfo Font;

    // Smoothed mouse pos text width to avoid flickering
    mutable float CrtMousePosTextWidth;

private:
    bool bIsSelecting;
    double SelectionStartTime;
    double SelectionEndTime;

    /**
     * The sorted list of all registered time markers. It defines the draw order of time markers.
     * The time marker currenly scrubbing will be moved at the end of the list in order to be displayed on top of other markers.
     */
    TArray<TSharedRef<Insights::FTimeMarker>> TimeMarkers;

    /** True if the user is currently dragging a time marker. */
    bool bIsScrubbing;
};

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