Carla/source/modules/juce_audio_devices/native/juce_android_Midi.cpp

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

   This file is part of the JUCE library.
   Copyright (c) 2016 - ROLI Ltd.

   Permission is granted to use this software under the terms of the ISC license
   http://www.isc.org/downloads/software-support-policy/isc-license/

   Permission to use, copy, modify, and/or distribute this software for any
   purpose with or without fee is hereby granted, provided that the above
   copyright notice and this permission notice appear in all copies.

   THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH REGARD
   TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
   FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT,
   OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
   USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
   TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
   OF THIS SOFTWARE.

   -----------------------------------------------------------------------------

   To release a closed-source product which uses other parts of JUCE not
   licensed under the ISC terms, commercial licenses are available: visit
   www.juce.com for more information.

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

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD) \
 METHOD (getJuceAndroidMidiInputDevices, "getJuceAndroidMidiInputDevices", "()[Ljava/lang/String;") \
 METHOD (getJuceAndroidMidiOutputDevices, "getJuceAndroidMidiOutputDevices", "()[Ljava/lang/String;") \
 METHOD (openMidiInputPortWithJuceIndex, "openMidiInputPortWithJuceIndex", "(IJ)L" JUCE_ANDROID_ACTIVITY_CLASSPATH "$JuceMidiPort;") \
 METHOD (openMidiOutputPortWithJuceIndex, "openMidiOutputPortWithJuceIndex", "(I)L" JUCE_ANDROID_ACTIVITY_CLASSPATH "$JuceMidiPort;") \
 METHOD (getInputPortNameForJuceIndex, "getInputPortNameForJuceIndex", "(I)Ljava/lang/String;") \
 METHOD (getOutputPortNameForJuceIndex, "getOutputPortNameForJuceIndex", "(I)Ljava/lang/String;")
 DECLARE_JNI_CLASS (MidiDeviceManager, JUCE_ANDROID_ACTIVITY_CLASSPATH "$MidiDeviceManager")
#undef JNI_CLASS_MEMBERS

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD) \
 METHOD (start, "start", "()V" )\
 METHOD (stop, "stop", "()V") \
 METHOD (close, "close", "()V") \
 METHOD (sendMidi, "sendMidi", "([BII)V")
 DECLARE_JNI_CLASS (JuceMidiPort, JUCE_ANDROID_ACTIVITY_CLASSPATH "$JuceMidiPort")
#undef JNI_CLASS_MEMBERS


//==============================================================================
class AndroidMidiInput
{
public:
    AndroidMidiInput (MidiInput* midiInput, int portIdx,
                      juce::MidiInputCallback* midiInputCallback, jobject deviceManager)
        : juceMidiInput (midiInput),
          callback (midiInputCallback),
          midiConcatenator (2048),
          javaMidiDevice (getEnv()->CallObjectMethod (deviceManager,
                                                      MidiDeviceManager.openMidiInputPortWithJuceIndex,
                                                      (jint) portIdx,
                                                      (jlong) this))
    {
    }

    ~AndroidMidiInput()
    {
        if (jobject d = javaMidiDevice.get())
        {
            getEnv()->CallVoidMethod (d, JuceMidiPort.close);
            javaMidiDevice.clear();
        }
    }

    bool isOpen() const noexcept
    {
        return javaMidiDevice != nullptr;
    }

    void start()
    {
        if (jobject d = javaMidiDevice.get())
            getEnv()->CallVoidMethod (d, JuceMidiPort.start);
    }

    void stop()
    {
        if (jobject d = javaMidiDevice.get())
            getEnv()->CallVoidMethod (d, JuceMidiPort.stop);

        callback = nullptr;
    }

    void receive (jbyteArray byteArray, jlong offset, jint len, jlong timestamp)
    {
        jassert (byteArray != nullptr);
        jbyte* data = getEnv()->GetByteArrayElements (byteArray, nullptr);

        HeapBlock<uint8> buffer (len);
        std::memcpy (buffer.getData(), data + offset, len);

        midiConcatenator.pushMidiData (buffer.getData(),
                                       len, static_cast<double> (timestamp) * 1.0e-9,
                                       juceMidiInput, *callback);

        getEnv()->ReleaseByteArrayElements (byteArray, data, 0);
    }

private:
    MidiInput* juceMidiInput;
    MidiInputCallback* callback;
    GlobalRef javaMidiDevice;
    MidiDataConcatenator midiConcatenator;
};

//==============================================================================
class AndroidMidiOutput
{
public:
    AndroidMidiOutput (jobject midiDevice)
        : javaMidiDevice (midiDevice)
    {
    }

    ~AndroidMidiOutput()
    {
        if (jobject d = javaMidiDevice.get())
        {
            getEnv()->CallVoidMethod (d, JuceMidiPort.close);
            javaMidiDevice.clear();
        }
    }

    void send (jbyteArray byteArray, jint offset, jint len)
    {
        if (jobject d = javaMidiDevice.get())
            getEnv()->CallVoidMethod (d,
                                      JuceMidiPort.sendMidi,
                                      byteArray, offset, len);
    }

private:
    GlobalRef javaMidiDevice;
};

JUCE_JNI_CALLBACK (JUCE_JOIN_MACRO (JUCE_ANDROID_ACTIVITY_CLASSNAME, _00024JuceMidiInputPort), handleReceive,
                   void, (JNIEnv* env, jobject device, jlong host, jbyteArray byteArray,
                          jint offset, jint count, jlong timestamp))
{
    // Java may create a Midi thread which JUCE doesn't know about and this callback may be
    // received on this thread. Java will have already created a JNI Env for this new thread,
    // which we need to tell Juce about
    setEnv (env);

    reinterpret_cast<AndroidMidiInput*> (host)->receive (byteArray, offset, count, timestamp);
}

//==============================================================================
class AndroidMidiDeviceManager
{
public:
    AndroidMidiDeviceManager()
        : deviceManager (android.activity.callObjectMethod (JuceAppActivity.getAndroidMidiDeviceManager))
    {
    }

    String getInputPortNameForJuceIndex (int idx)
    {
        if (jobject dm = deviceManager.get())
        {
            LocalRef<jstring> string ((jstring) getEnv()->CallObjectMethod (dm, MidiDeviceManager.getInputPortNameForJuceIndex, idx));
            return juceString (string);
        }

        return String();
    }

    String getOutputPortNameForJuceIndex (int idx)
    {
        if (jobject dm = deviceManager.get())
        {
            LocalRef<jstring> string ((jstring) getEnv()->CallObjectMethod (dm, MidiDeviceManager.getOutputPortNameForJuceIndex, idx));
            return juceString (string);
        }

        return String();
    }

    StringArray getDevices (bool input)
    {
        if (jobject dm = deviceManager.get())
        {
            jobjectArray jDevices
                = (jobjectArray) getEnv()->CallObjectMethod (dm, input ? MidiDeviceManager.getJuceAndroidMidiInputDevices
                                                                  : MidiDeviceManager.getJuceAndroidMidiOutputDevices);

            // Create a local reference as converting this
            // to a JUCE string will call into JNI
            LocalRef<jobjectArray> devices (jDevices);
            return javaStringArrayToJuce (devices);
        }

        return StringArray();
    }

    AndroidMidiInput* openMidiInputPortWithIndex (int idx, MidiInput* juceMidiInput, juce::MidiInputCallback* callback)
    {
        if (jobject dm = deviceManager.get())
        {
            ScopedPointer<AndroidMidiInput> androidMidiInput (new AndroidMidiInput (juceMidiInput, idx, callback, dm));

            if (androidMidiInput->isOpen())
                return androidMidiInput.release();
        }

        return nullptr;
    }

    AndroidMidiOutput* openMidiOutputPortWithIndex (int idx)
    {
        if (jobject dm = deviceManager.get())
            if (jobject javaMidiPort = getEnv()->CallObjectMethod (dm, MidiDeviceManager.openMidiOutputPortWithJuceIndex, (jint) idx))
                return new AndroidMidiOutput (javaMidiPort);

        return nullptr;
    }

private:
    static StringArray javaStringArrayToJuce (jobjectArray jStrings)
    {
        StringArray retval;

        JNIEnv* env = getEnv();
        const int count = env->GetArrayLength (jStrings);

        for (int i = 0; i < count; ++i)
        {
            LocalRef<jstring> string ((jstring) env->GetObjectArrayElement (jStrings, i));
            retval.add (juceString (string));
        }

        return retval;
    }

    GlobalRef deviceManager;
};

//==============================================================================
StringArray MidiOutput::getDevices()
{
    AndroidMidiDeviceManager manager;
    return manager.getDevices (false);
}

int MidiOutput::getDefaultDeviceIndex()
{
    return 0;
}

MidiOutput* MidiOutput::openDevice (int index)
{
    if (index < 0)
        return nullptr;

    AndroidMidiDeviceManager manager;

    String midiOutputName = manager.getOutputPortNameForJuceIndex (index);

    if (midiOutputName.isEmpty())
    {
        // you supplied an invalid device index!
        jassertfalse;
        return nullptr;
    }

    if (AndroidMidiOutput* midiOutput = manager.openMidiOutputPortWithIndex (index))
    {
        MidiOutput* retval = new MidiOutput (midiOutputName);
        retval->internal = midiOutput;

        return retval;
    }

    return nullptr;
}

MidiOutput::~MidiOutput()
{
    stopBackgroundThread();

    delete reinterpret_cast<AndroidMidiOutput*> (internal);
}

void MidiOutput::sendMessageNow (const MidiMessage& message)
{
    if (AndroidMidiOutput* androidMidi = reinterpret_cast<AndroidMidiOutput*>(internal))
    {
        JNIEnv* env = getEnv();
        const int messageSize = message.getRawDataSize();

        LocalRef<jbyteArray> messageContent = LocalRef<jbyteArray> (env->NewByteArray (messageSize));
        jbyteArray content = messageContent.get();

        jbyte* rawBytes = env->GetByteArrayElements (content, nullptr);
        std::memcpy (rawBytes, message.getRawData(), messageSize);
        env->ReleaseByteArrayElements (content, rawBytes, 0);

        androidMidi->send (content, (jint) 0, (jint) messageSize);
    }
}

//==============================================================================
MidiInput::MidiInput (const String& nm)  : name (nm)
{
}

StringArray MidiInput::getDevices()
{
    AndroidMidiDeviceManager manager;
    return manager.getDevices (true);
}

int MidiInput::getDefaultDeviceIndex()
{
    return 0;
}

MidiInput* MidiInput::openDevice (int index, juce::MidiInputCallback* callback)
{
    if (index < 0)
        return nullptr;

    AndroidMidiDeviceManager manager;

    String midiInputName = manager.getInputPortNameForJuceIndex (index);

    if (midiInputName.isEmpty())
    {
        // you supplied an invalid device index!
        jassertfalse;
        return nullptr;
    }

    ScopedPointer<MidiInput> midiInput (new MidiInput (midiInputName));

    midiInput->internal = manager.openMidiInputPortWithIndex (index, midiInput, callback);

    return midiInput->internal != nullptr ? midiInput.release()
                                          : nullptr;
}

void MidiInput::start()
{
    if (AndroidMidiInput* mi = reinterpret_cast<AndroidMidiInput*> (internal))
        mi->start();
}

void MidiInput::stop()
{
    if (AndroidMidiInput* mi = reinterpret_cast<AndroidMidiInput*> (internal))
        mi->stop();
}

MidiInput::~MidiInput()
{
    delete reinterpret_cast<AndroidMidiInput*> (internal);
}