Carla/source/modules/juce_gui_basics/filebrowser/juce_ContentSharer.cpp

/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

#if JUCE_CONTENT_SHARING
//==============================================================================
class ContentSharer::PrepareImagesThread    : private Thread
{
public:
    PrepareImagesThread (ContentSharer& cs, const Array<Image>& imagesToUse,
                         ImageFileFormat* imageFileFormatToUse)
        : Thread ("ContentSharer::PrepareImagesThread"),
          owner (cs),
          images (imagesToUse),
          imageFileFormat (imageFileFormatToUse == nullptr ? new PNGImageFormat()
                                                           : imageFileFormatToUse),
          extension (imageFileFormat->getFormatName().toLowerCase())
    {
        startThread();
    }

    ~PrepareImagesThread() override
    {
        signalThreadShouldExit();
        waitForThreadToExit (10000);
    }

private:
    void run() override
    {
        for (const auto& image : images)
        {
            if (threadShouldExit())
                return;

            File tempFile = File::createTempFile (extension);

            if (! tempFile.create().wasOk())
                break;

            std::unique_ptr<FileOutputStream> outputStream (tempFile.createOutputStream());

            if (outputStream == nullptr)
                break;

            if (imageFileFormat->writeImageToStream (image, *outputStream))
                owner.temporaryFiles.add (tempFile);
        }

        finish();
    }

    void finish()
    {
        MessageManager::callAsync ([this] () { owner.filesToSharePrepared(); });
    }

    ContentSharer& owner;
    const Array<Image> images;
    std::unique_ptr<ImageFileFormat> imageFileFormat;
    String extension;
};

//==============================================================================
class ContentSharer::PrepareDataThread    : private Thread
{
public:
    PrepareDataThread (ContentSharer& cs, const MemoryBlock& mb)
        : Thread ("ContentSharer::PrepareDataThread"),
          owner (cs),
          data (mb)
    {
        startThread();
    }

    ~PrepareDataThread() override
    {
        signalThreadShouldExit();
        waitForThreadToExit (10000);
    }

private:
    void run() override
    {
        File tempFile = File::createTempFile ("data");

        if (tempFile.create().wasOk())
        {
            if (auto outputStream = std::unique_ptr<FileOutputStream> (tempFile.createOutputStream()))
            {
                size_t pos = 0;
                size_t totalSize = data.getSize();

                while (pos < totalSize)
                {
                    if (threadShouldExit())
                        return;

                    size_t numToWrite = std::min ((size_t) 8192, totalSize - pos);

                    outputStream->write (data.begin() + pos, numToWrite);

                    pos += numToWrite;
                }

                owner.temporaryFiles.add (tempFile);
            }
        }

        finish();
    }

    void finish()
    {
        MessageManager::callAsync ([this] () { owner.filesToSharePrepared(); });
    }

    ContentSharer& owner;
    const MemoryBlock data;
};
#endif

//==============================================================================
JUCE_IMPLEMENT_SINGLETON (ContentSharer)

ContentSharer::ContentSharer() {}
ContentSharer::~ContentSharer() { clearSingletonInstance(); }

void ContentSharer::shareFiles (const Array<URL>& files,
                                std::function<void(bool, const String&)> callbackToUse)
{
  #if JUCE_CONTENT_SHARING
    startNewShare (callbackToUse);
    pimpl->shareFiles (files);
  #else
    ignoreUnused (files);

    // Content sharing is not available on this platform!
    jassertfalse;

    if (callbackToUse)
        callbackToUse (false, "Content sharing is not available on this platform!");
  #endif
}

#if JUCE_CONTENT_SHARING
void ContentSharer::startNewShare (std::function<void(bool, const String&)> callbackToUse)
{
    // You should not start another sharing operation before the previous one is finished.
    // Forcibly stopping a previous sharing operation is rarely a good idea!
    jassert (pimpl == nullptr);
    pimpl.reset();

    prepareDataThread = nullptr;
    prepareImagesThread = nullptr;

    deleteTemporaryFiles();

    // You need to pass a valid callback.
    jassert (callbackToUse);
    callback = std::move (callbackToUse);

    pimpl.reset (createPimpl());
}
#endif

void ContentSharer::shareText (const String& text,
                               std::function<void(bool, const String&)> callbackToUse)
{
  #if JUCE_CONTENT_SHARING
    startNewShare (callbackToUse);
    pimpl->shareText (text);
  #else
    ignoreUnused (text);

    // Content sharing is not available on this platform!
    jassertfalse;

    if (callbackToUse)
        callbackToUse (false, "Content sharing is not available on this platform!");
  #endif
}

void ContentSharer::shareImages (const Array<Image>& images,
                                 std::function<void(bool, const String&)> callbackToUse,
                                 ImageFileFormat* imageFileFormatToUse)
{
  #if JUCE_CONTENT_SHARING
    startNewShare (callbackToUse);
    prepareImagesThread.reset (new PrepareImagesThread (*this, images, imageFileFormatToUse));
  #else
    ignoreUnused (images, imageFileFormatToUse);

    // Content sharing is not available on this platform!
    jassertfalse;

    if (callbackToUse)
        callbackToUse (false, "Content sharing is not available on this platform!");
  #endif
}

#if JUCE_CONTENT_SHARING
void ContentSharer::filesToSharePrepared()
{
    Array<URL> urls;

    for (const auto& tempFile : temporaryFiles)
        urls.add (URL (tempFile));

    prepareImagesThread = nullptr;
    prepareDataThread = nullptr;

    pimpl->shareFiles (urls);
}
#endif

void ContentSharer::shareData (const MemoryBlock& mb,
                               std::function<void(bool, const String&)> callbackToUse)
{
  #if JUCE_CONTENT_SHARING
    startNewShare (callbackToUse);
    prepareDataThread.reset (new PrepareDataThread (*this, mb));
  #else
    ignoreUnused (mb);

    if (callbackToUse)
        callbackToUse (false, "Content sharing not available on this platform!");
  #endif
}

void ContentSharer::sharingFinished (bool succeeded, const String& errorDescription)
{
    deleteTemporaryFiles();

    std::function<void(bool, String)> cb;
    std::swap (cb, callback);

    String error (errorDescription);

  #if JUCE_CONTENT_SHARING
    pimpl.reset();
  #endif

    if (cb)
        cb (succeeded, error);
}

void ContentSharer::deleteTemporaryFiles()
{
    for (auto& f : temporaryFiles)
        f.deleteFile();

    temporaryFiles.clear();
}

} // namespace juce