// Copyright 1998-2015 Epic Games, Inc. All Rights Reserved.

#include "ProfilerPrivatePCH.h"

// @TODO yrx 2014-04-18 Move SProfilerWindow later
#define LOCTEXT_NAMESPACE "SProfilerGraphPanel"

SProfilerGraphPanel::SProfilerGraphPanel()
	: bLockMiniViewState( false )
	, NumDataPoints( 0 )
	, NumVisiblePoints( 0 )
	, GraphOffset( 0 )
	, ViewMode( EProfilerViewMode::InvalidOrMax )
{}

SProfilerGraphPanel::~SProfilerGraphPanel()
{
	// Remove ourselves from the profiler manager.
	auto ProfilerManager = FProfilerManager::Get();
	if( ProfilerManager.IsValid() )
	{
		ProfilerManager->OnTrackedStatChanged().RemoveAll( this );
		ProfilerManager->OnSessionInstancesUpdated().RemoveAll( this );
		ProfilerManager->OnViewModeChanged().RemoveAll( this );

		DataGraph->OnSelectionChangedForIndex().RemoveAll( ProfilerManager.Get() );

		if( ProfilerMiniView.Pin().IsValid() )
		{
			ProfilerMiniView.Pin()->OnSelectionBoxChanged().RemoveAll( this );
		}
	}

	ThreadView->OnViewPositionXChanged().RemoveAll( this );
	ThreadView->OnViewPositionYChanged().RemoveAll( this );
}

void SProfilerGraphPanel::Construct( const FArguments& InArgs )
{
	ChildSlot
	[
		SNew( SBorder )
		.BorderImage( FEditorStyle::GetBrush( "ToolPanel.GroupBorder" ) )
		.Padding( 2.0f )
		[
			SNew( SHorizontalBox )

			+ SHorizontalBox::Slot()
			.FillWidth( 1.0f )
			[
				SNew( SVerticalBox )

				// At this moment only one widget of these two can be visible at once.
				//
				// DataGraph
				+SVerticalBox::Slot()
				.FillHeight( 1.0f )
				[
					SAssignNew( DataGraph, SDataGraph )
					.OnGraphOffsetChanged( this, &SProfilerGraphPanel::OnDataGraphGraphOffsetChanged )
				]

				// ThreadView
				+ SVerticalBox::Slot()
				.FillHeight( 1.0f )
				[
					SAssignNew( ThreadView, SProfilerThreadView )
				]

				+ SVerticalBox::Slot()
				.AutoHeight()
				[
					SAssignNew( HorizontalScrollBar, SScrollBar )
					.Orientation( Orient_Horizontal )
					.AlwaysShowScrollbar( true )
					.Visibility( EVisibility::Visible )
					.Thickness( FVector2D( 8.0f, 8.0f ) )
					.OnUserScrolled( this, &SProfilerGraphPanel::HorizontalScrollBar_OnUserScrolled )
				]
			]

			+ SHorizontalBox::Slot()
			.AutoWidth()
			[
				SAssignNew( VerticalScrollBar, SScrollBar )
				.Orientation( Orient_Vertical )
				.AlwaysShowScrollbar( true )
				.Visibility( EVisibility::Visible )
				.Thickness( FVector2D( 8.0f, 8.0f ) )
				.OnUserScrolled( this, &SProfilerGraphPanel::VerticalScrollBar_OnUserScrolled )
			]
		]
	];

	HorizontalScrollBar->SetState( 0.0f, 1.0f );
	VerticalScrollBar->SetState( 0.0f, 1.0f );

	// Register ourselves with the profiler manager.
	FProfilerManager::Get()->OnTrackedStatChanged().AddSP( this, &SProfilerGraphPanel::ProfilerManager_OnTrackedStatChanged );
	FProfilerManager::Get()->OnViewModeChanged().AddSP( this, &SProfilerGraphPanel::ProfilerManager_OnViewModeChanged );

	DataGraph->OnSelectionChangedForIndex().AddSP( FProfilerManager::Get().ToSharedRef(), &FProfilerManager::DataGraph_OnSelectionChangedForIndex );

	ThreadView->OnViewPositionXChanged().AddSP( this, &SProfilerGraphPanel::ThreadView_OnViewPositionXChanged );
	ThreadView->OnViewPositionYChanged().AddSP( this, &SProfilerGraphPanel::ThreadView_OnViewPositionYChanged );
}


void SProfilerGraphPanel::Tick( const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime )
{
	UpdateInternals();
}

void SProfilerGraphPanel::HorizontalScrollBar_OnUserScrolled( float ScrollOffset )
{
	if( ViewMode == EProfilerViewMode::LineIndexBased )
	{
		const float ThumbSizeFraction = FMath::Min( (float)NumVisiblePoints / (float)NumDataPoints, 1.0f );
		ScrollOffset = FMath::Min( ScrollOffset, 1.0f - ThumbSizeFraction );

		HorizontalScrollBar->SetState( ScrollOffset, ThumbSizeFraction );

		GraphOffset = FMath::TruncToInt( ScrollOffset * NumDataPoints );
		DataGraph->ScrollTo( GraphOffset );

		ProfilerMiniView.Pin()->MoveWithoutZoomSelectionBox( GraphOffset, GraphOffset + NumVisiblePoints );
	}
	else if( ViewMode == EProfilerViewMode::ThreadViewTimeBased )
	{
		ThreadView->SetPositionXToByScrollBar( ScrollOffset );
	}
}


void SProfilerGraphPanel::VerticalScrollBar_OnUserScrolled( float ScrollOffset )
{
	// @TODO yrx 2014-04-24 Broadcast?
	if( ViewMode == EProfilerViewMode::LineIndexBased )
	{

	}
	else if( ViewMode == EProfilerViewMode::ThreadViewTimeBased )
	{
		// @TODO yrx 2014-04-23 
		ThreadView->SetPositonYTo( ScrollOffset );
	}
}


void SProfilerGraphPanel::ProfilerManager_OnTrackedStatChanged( const FTrackedStat& TrackedStat, bool bIsTracked )
{
	if( bIsTracked )
	{
		DataGraph->AddInnerGraph( TrackedStat.StatID, TrackedStat.ColorAverage, TrackedStat.ColorBackground, TrackedStat.ColorExtremes, TrackedStat.CombinedGraphDataSource );
	}
	else
	{
		DataGraph->RemoveInnerGraph( TrackedStat.StatID );
	}
}

void SProfilerGraphPanel::OnDataGraphGraphOffsetChanged( int32 InGraphOffset )
{
	GraphOffset = InGraphOffset;
	SetScrollBarState();
	ProfilerMiniView.Pin()->MoveWithoutZoomSelectionBox( InGraphOffset, InGraphOffset + NumVisiblePoints );
}

void SProfilerGraphPanel::MiniView_OnSelectionBoxChanged( int32 FrameStart, int32 FrameEnd )
{
	if( ViewMode == EProfilerViewMode::LineIndexBased )
	{
		GraphOffset = FrameStart;
		SetScrollBarState();
		DataGraph->ScrollTo( GraphOffset );
	}
	else if( ViewMode == EProfilerViewMode::ThreadViewTimeBased )
	{
		TGuardValue<bool> LockedMiniViewState( bLockMiniViewState, true );
		// Update thread-view state.
		ThreadView->SetFrameRange( FrameStart, FrameEnd );
	}
}

void SProfilerGraphPanel::ThreadView_OnViewPositionXChanged( double FrameStartMS, double FrameEndMS, double MaxEndTimeMS, int32 FrameStart, int32 FrameEnd )
{
	const double MinStartTimeMS = 0.0f;
	const double TotalRangeMS = MaxEndTimeMS - MinStartTimeMS;
	const double ThisFrameRangeMS = FrameEndMS - FrameStartMS;

	const double ThumbSizeFraction = ThisFrameRangeMS / TotalRangeMS;
	const double OffsetFraction = FrameStartMS / MaxEndTimeMS;

	// Update horizontal scroll bar state.
	HorizontalScrollBar->SetState( (float)OffsetFraction, (float)ThumbSizeFraction );

	if( !bLockMiniViewState )
	{
		// Update profiler mini-view state.
		ProfilerMiniView.Pin()->MoveAndZoomSelectionBox( FrameStart, FrameEnd );
	}
}

void SProfilerGraphPanel::ThreadView_OnViewPositionYChanged( double PosStartY, double PosYEnd, double MaxPosY )
{
	const double MinPosY = 0.0f;
	const double TotalRangeY = MaxPosY - MinPosY;
	const double ThisRangeY = PosYEnd - PosStartY;

	const double ThumbSizeFraction = ThisRangeY / TotalRangeY;
	const double OffsetFraction = PosStartY / MaxPosY;

	VerticalScrollBar->SetState( (float)OffsetFraction, (float)ThumbSizeFraction );
}

void SProfilerGraphPanel::ProfilerManager_OnViewModeChanged( EProfilerViewMode::Type NewViewMode )
{
	if( NewViewMode == EProfilerViewMode::LineIndexBased )
	{
		VerticalScrollBar->SetVisibility( EVisibility::Collapsed );
		VerticalScrollBar->SetEnabled( false );

		DataGraph->SetVisibility( EVisibility::Visible );
		DataGraph->SetEnabled( true );
		ThreadView->SetVisibility( EVisibility::Collapsed );
		ThreadView->SetEnabled( false );
	}
	else if( NewViewMode == EProfilerViewMode::ThreadViewTimeBased )
	{
		VerticalScrollBar->SetVisibility( EVisibility::Visible );
		VerticalScrollBar->SetEnabled( true );

		DataGraph->SetVisibility( EVisibility::Collapsed );
		DataGraph->SetEnabled( false );
		ThreadView->SetVisibility( EVisibility::Visible );
		ThreadView->SetEnabled( true );
	}

	ViewMode = NewViewMode;
}


void SProfilerGraphPanel::UpdateInternals()
{
	if( ViewMode == EProfilerViewMode::LineIndexBased )
	{
		NumVisiblePoints = DataGraph->GetNumVisiblePoints();
		NumDataPoints = DataGraph->GetNumDataPoints();

		SetScrollBarState();
		ProfilerMiniView.Pin()->MoveWithoutZoomSelectionBox( GraphOffset, GraphOffset + NumVisiblePoints );

		if( FProfilerManager::Get()->IsLivePreview() )
		{
			// Scroll to the end.
			HorizontalScrollBar_OnUserScrolled( 1.0f );
		}
	}
	else if( ViewMode == EProfilerViewMode::ThreadViewTimeBased )
	{
		// @TODO yrx 2014-04-23 
	}
}

void SProfilerGraphPanel::SetScrollBarState()
{
	// Note that the maximum offset is 1.0-ThumbSizeFraction.
	// If the user can view 1/3 of the items in a single page, the maximum offset will be ~0.667f
	const float ThumbSizeFraction = FMath::Min( (float)NumVisiblePoints / (float)NumDataPoints, 1.0f );
	const float OffsetFraction = (float)GraphOffset / (float)NumDataPoints;
	HorizontalScrollBar->SetState( OffsetFraction, ThumbSizeFraction );
}



#undef LOCTEXT_NAMESPACE