#include "OpenGLVideoIOBridge.h"

#include "HealthTelemetry.h"
#include "RenderEngine.h"

#include <chrono>

OpenGLVideoIOBridge::OpenGLVideoIOBridge(
	VideoIODevice& videoIO,
	RenderEngine& renderEngine,
	HealthTelemetry& healthTelemetry) :
	mVideoIO(videoIO),
	mRenderEngine(renderEngine),
	mHealthTelemetry(healthTelemetry)
{
}

void OpenGLVideoIOBridge::RecordFramePacing(VideoIOCompletionResult completionResult)
{
	const auto now = std::chrono::steady_clock::now();
	if (mLastPlayoutCompletionTime != std::chrono::steady_clock::time_point())
	{
		mCompletionIntervalMilliseconds = std::chrono::duration_cast<std::chrono::duration<double, std::milli>>(now - mLastPlayoutCompletionTime).count();
		if (mSmoothedCompletionIntervalMilliseconds <= 0.0)
			mSmoothedCompletionIntervalMilliseconds = mCompletionIntervalMilliseconds;
		else
			mSmoothedCompletionIntervalMilliseconds = mSmoothedCompletionIntervalMilliseconds * 0.9 + mCompletionIntervalMilliseconds * 0.1;
		if (mCompletionIntervalMilliseconds > mMaxCompletionIntervalMilliseconds)
			mMaxCompletionIntervalMilliseconds = mCompletionIntervalMilliseconds;
	}
	mLastPlayoutCompletionTime = now;

	if (completionResult == VideoIOCompletionResult::DisplayedLate)
		++mLateFrameCount;
	else if (completionResult == VideoIOCompletionResult::Dropped)
		++mDroppedFrameCount;
	else if (completionResult == VideoIOCompletionResult::Flushed)
		++mFlushedFrameCount;

	mHealthTelemetry.TryRecordFramePacingStats(
		mCompletionIntervalMilliseconds,
		mSmoothedCompletionIntervalMilliseconds,
		mMaxCompletionIntervalMilliseconds,
		mLateFrameCount,
		mDroppedFrameCount,
		mFlushedFrameCount);
}

void OpenGLVideoIOBridge::VideoFrameArrived(const VideoIOFrame& inputFrame)
{
	const VideoIOState& state = mVideoIO.State();
	mHealthTelemetry.TryReportSignalStatus(!inputFrame.hasNoInputSource, state.inputFrameSize.width, state.inputFrameSize.height, state.inputDisplayModeName);

	if (inputFrame.hasNoInputSource || inputFrame.bytes == nullptr)
		return;							// don't transfer texture when there's no input

	mRenderEngine.TryUploadInputFrame(inputFrame, state);
}

void OpenGLVideoIOBridge::PlayoutFrameCompleted(const VideoIOCompletion& completion)
{
	RecordFramePacing(completion.result);

	VideoIOOutputFrame outputFrame;
	if (!mVideoIO.BeginOutputFrame(outputFrame))
		return;
	const VideoIOState& state = mVideoIO.State();
	RenderPipelineFrameContext frameContext;
	frameContext.videoState = state;
	frameContext.completion = completion;

	mRenderEngine.RenderOutputFrame(frameContext, outputFrame);

	mVideoIO.EndOutputFrame(outputFrame);

	mVideoIO.AccountForCompletionResult(completion.result);

	// Schedule the next frame for playout after the GL bridge is released so
	// input uploads are not blocked by non-GL output bookkeeping.
	mVideoIO.ScheduleOutputFrame(outputFrame);
}