/*
 * Copyright (C) 2020 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "RemoteCaptureSampleManager.h"

#include "Logging.h"
#include "RemoteCaptureSampleManagerMessages.h"
#include "SharedRingBufferStorage.h"
#include "WebProcess.h"
#include <WebCore/ImageTransferSessionVT.h>
#include <WebCore/RemoteVideoSample.h>
#include <WebCore/WebAudioBufferList.h>

#if PLATFORM(COCOA) && ENABLE(MEDIA_STREAM)

namespace WebKit {
using namespace WebCore;

RemoteCaptureSampleManager::RemoteCaptureSampleManager()
    : m_queue(WorkQueue::create("RemoteCaptureSampleManager", WorkQueue::QOS::UserInteractive))
{
}

RemoteCaptureSampleManager::~RemoteCaptureSampleManager()
{
    ASSERT(!m_connection);
}

void RemoteCaptureSampleManager::stopListeningForIPC()
{
    if (m_isRegisteredToParentProcessConnection)
        WebProcess::singleton().parentProcessConnection()->removeThreadMessageReceiver(Messages::RemoteCaptureSampleManager::messageReceiverName());
    setConnection(nullptr);
}

void RemoteCaptureSampleManager::setConnection(IPC::Connection* connection)
{
    if (m_connection == connection)
        return;

    auto* parentConnection = WebProcess::singleton().parentProcessConnection();
    if (connection == parentConnection) {
        if (!m_isRegisteredToParentProcessConnection) {
            m_isRegisteredToParentProcessConnection = true;
            parentConnection->addThreadMessageReceiver(Messages::RemoteCaptureSampleManager::messageReceiverName(), this);
        }
        return;
    }
    if (m_connection)
        m_connection->removeThreadMessageReceiver(Messages::RemoteCaptureSampleManager::messageReceiverName());

    m_connection = WTFMove(connection);

    if (m_connection)
        m_connection->addThreadMessageReceiver(Messages::RemoteCaptureSampleManager::messageReceiverName(), this);
}

void RemoteCaptureSampleManager::addSource(Ref<RemoteRealtimeAudioSource>&& source)
{
    ASSERT(WTF::isMainRunLoop());
    setConnection(source->connection());

    m_queue->dispatch([this, protectedThis = Ref { *this }, source = WTFMove(source)]() mutable {
        auto identifier = source->identifier();

        ASSERT(!m_audioSources.contains(identifier));
        m_audioSources.add(identifier, makeUnique<RemoteAudio>(WTFMove(source)));
    });
}

void RemoteCaptureSampleManager::addSource(Ref<RemoteRealtimeVideoSource>&& source)
{
    ASSERT(WTF::isMainRunLoop());
    setConnection(source->connection());

    m_queue->dispatch([this, protectedThis = Ref { *this }, source = WTFMove(source)]() mutable {
        auto identifier = source->identifier();

        ASSERT(!m_videoSources.contains(identifier));
        m_videoSources.add(identifier, makeUnique<RemoteVideo>(WTFMove(source)));
    });
}

void RemoteCaptureSampleManager::addSource(Ref<RemoteRealtimeDisplaySource>&& source)
{
    ASSERT(WTF::isMainRunLoop());
    setConnection(source->connection());

    m_queue->dispatch([this, protectedThis = Ref { *this }, source = WTFMove(source)]() mutable {
        auto identifier = source->identifier();

        ASSERT(!m_videoSources.contains(identifier));
        m_videoSources.add(identifier, makeUnique<RemoteVideo>(WTFMove(source)));
    });
}

void RemoteCaptureSampleManager::removeSource(WebCore::RealtimeMediaSourceIdentifier identifier)
{
    ASSERT(WTF::isMainRunLoop());
    m_queue->dispatch([this, protectedThis = Ref { *this }, identifier] {
        ASSERT(m_audioSources.contains(identifier) || m_videoSources.contains(identifier));
        if (!m_audioSources.remove(identifier))
            m_videoSources.remove(identifier);
    });
}

void RemoteCaptureSampleManager::didUpdateSourceConnection(IPC::Connection* connection)
{
    ASSERT(WTF::isMainRunLoop());
    setConnection(connection);
}

void RemoteCaptureSampleManager::dispatchToThread(Function<void()>&& callback)
{
    m_queue->dispatch(WTFMove(callback));
}

void RemoteCaptureSampleManager::audioStorageChanged(WebCore::RealtimeMediaSourceIdentifier identifier, const SharedMemory::IPCHandle& ipcHandle, const WebCore::CAAudioStreamDescription& description, uint64_t numberOfFrames, IPC::Semaphore&& semaphore, const MediaTime& mediaTime, size_t frameChunkSize)
{
    ASSERT(!WTF::isMainRunLoop());

    auto iterator = m_audioSources.find(identifier);
    if (iterator == m_audioSources.end()) {
        RELEASE_LOG_ERROR(WebRTC, "Unable to find source %llu for storageChanged", identifier.toUInt64());
        return;
    }
    iterator->value->setStorage(ipcHandle.handle, description, numberOfFrames, WTFMove(semaphore), mediaTime, frameChunkSize);
}

void RemoteCaptureSampleManager::videoSampleAvailable(RealtimeMediaSourceIdentifier identifier, RemoteVideoSample&& sample, VideoSampleMetadata metadata)
{
    ASSERT(!WTF::isMainRunLoop());

    auto iterator = m_videoSources.find(identifier);
    if (iterator == m_videoSources.end()) {
        RELEASE_LOG_ERROR(WebRTC, "Unable to find source %llu for remoteVideoSampleAvailable", identifier.toUInt64());
        return;
    }
    iterator->value->videoSampleAvailable(WTFMove(sample), metadata);
}

RemoteCaptureSampleManager::RemoteAudio::RemoteAudio(Ref<RemoteRealtimeAudioSource>&& source)
    : m_source(WTFMove(source))
{
}

RemoteCaptureSampleManager::RemoteAudio::~RemoteAudio()
{
    stopThread();
}

void RemoteCaptureSampleManager::RemoteAudio::stopThread()
{
    if (!m_thread)
        return;

    m_shouldStopThread = true;
    m_semaphore.signal();
    m_thread->waitForCompletion();
    m_thread = nullptr;
}

void RemoteCaptureSampleManager::RemoteAudio::startThread()
{
    ASSERT(!m_thread);
    m_shouldStopThread = false;
    auto threadLoop = [this]() mutable {
        m_readOffset = 0;
        do {
            // If wait fails, the semaphore on the other side was probably destroyed and we should just exit here and wait to launch a new thread.
            if (!m_semaphore.wait())
                break;
            if (m_shouldStopThread)
                break;

            auto currentTime = m_startTime + MediaTime { m_readOffset, static_cast<uint32_t>(m_description.sampleRate()) };
            m_ringBuffer->fetch(m_buffer->list(), m_frameChunkSize, m_readOffset);
            m_readOffset += m_frameChunkSize;

            m_source->remoteAudioSamplesAvailable(currentTime, *m_buffer, m_description, m_frameChunkSize);
        } while (!m_shouldStopThread);
    };
    m_thread = Thread::create("RemoteCaptureSampleManager::RemoteAudio thread", WTFMove(threadLoop), ThreadType::Audio, Thread::QOS::UserInteractive);
}

void RemoteCaptureSampleManager::RemoteAudio::setStorage(const SharedMemory::Handle& handle, const WebCore::CAAudioStreamDescription& description, uint64_t numberOfFrames, IPC::Semaphore&& semaphore, const MediaTime& mediaTime, size_t frameChunkSize)
{
    stopThread();

    if (!numberOfFrames) {
        m_ringBuffer = nullptr;
        m_buffer = nullptr;
        return;
    }

    m_semaphore = WTFMove(semaphore);
    m_description = description;
    m_startTime = mediaTime;
    m_frameChunkSize = frameChunkSize;

    m_ringBuffer = CARingBuffer::adoptStorage(makeUniqueRef<ReadOnlySharedRingBufferStorage>(handle), description, numberOfFrames).moveToUniquePtr();
    m_buffer = makeUnique<WebAudioBufferList>(description, m_frameChunkSize);

    startThread();
}

RemoteCaptureSampleManager::RemoteVideo::RemoteVideo(Source&& source)
    : m_source(WTFMove(source))
{
}

void RemoteCaptureSampleManager::RemoteVideo::videoSampleAvailable(RemoteVideoSample&& remoteSample, VideoSampleMetadata metadata)
{
    if (!m_imageTransferSession || m_imageTransferSession->pixelFormat() != remoteSample.videoFormat())
        m_imageTransferSession = ImageTransferSessionVT::create(remoteSample.videoFormat());

    if (!m_imageTransferSession) {
        ASSERT_NOT_REACHED();
        return;
    }

    auto sampleRef = m_imageTransferSession->createMediaSample(remoteSample);
    if (!sampleRef) {
        ASSERT_NOT_REACHED();
        return;
    }
    switchOn(m_source, [&](Ref<RemoteRealtimeVideoSource>& source) {
        source->videoSampleAvailable(*sampleRef, remoteSample.size(), metadata);
    }, [&](Ref<RemoteRealtimeDisplaySource>& source) {
        source->remoteVideoSampleAvailable(*sampleRef, metadata);
    });
}

}

#endif