#include "AudioConsumer.h"
#include "AudioRecorder.h"
#include "AudioFilter.h"
#include "../AudioInput.h"
#include "../filter/Filter.h"
#include "../filter/FilterVad.h"
#include "../filter/FilterThreshold.h"
#include "../filter/FilterState.h"
#include "../../logger.h"

using namespace std;
using namespace tc::audio;
using namespace tc::audio::recorder;

NAN_MODULE_INIT(AudioConsumerWrapper::Init) {
	auto klass = Nan::New<v8::FunctionTemplate>(AudioConsumerWrapper::NewInstance);
	klass->SetClassName(Nan::New("AudioConsumer").ToLocalChecked());
	klass->InstanceTemplate()->SetInternalFieldCount(1);

	Nan::SetPrototypeMethod(klass, "get_filters", AudioConsumerWrapper::_get_filters);
	Nan::SetPrototypeMethod(klass, "unregister_filter", AudioConsumerWrapper::_unregister_filter);

	Nan::SetPrototypeMethod(klass, "create_filter_vad", AudioConsumerWrapper::_create_filter_vad);
	Nan::SetPrototypeMethod(klass, "create_filter_threshold", AudioConsumerWrapper::_create_filter_threshold);
	Nan::SetPrototypeMethod(klass, "create_filter_state", AudioConsumerWrapper::_create_filter_state);

	constructor_template().Reset(klass);
	constructor().Reset(Nan::GetFunction(klass).ToLocalChecked());
}

NAN_METHOD(AudioConsumerWrapper::NewInstance) {
	if(!info.IsConstructCall())
		Nan::ThrowError("invalid invoke!");
}

AudioConsumerWrapper::AudioConsumerWrapper(AudioRecorderWrapper* h, const std::shared_ptr<tc::audio::AudioConsumer> &handle) : _handle(handle), _recorder(h) {
	log_allocate("AudioConsumerWrapper", this);
	{
		lock_guard read_lock(handle->on_read_lock);
		handle->on_read = [&](const void* buffer, size_t length){ this->process_data(buffer, length); };
	}

#ifdef DO_DEADLOCK_REF
	this->_recorder->js_ref(); /* FML Mem leak! (In general the consumer live is related to the recorder handle, but for nodejs testing we want to keep this reference ) */
#endif
}

AudioConsumerWrapper::~AudioConsumerWrapper() {
	log_free("AudioConsumerWrapper", this);

	lock_guard lock(this->execute_lock);
	this->unbind();
	if(this->_handle->handle) {
		this->_handle->handle->delete_consumer(this->_handle);
		this->_handle = nullptr;
	}

#ifdef DO_DEADLOCK_REF
	if(this->_recorder)
		this->_recorder->js_unref();
#endif
}

void AudioConsumerWrapper::do_wrap(const v8::Local<v8::Object> &obj) {
	this->Wrap(obj);

	this->_call_data = Nan::async_callback([&] {
		Nan::HandleScope scope;

		auto handle = this->handle();
		v8::Local<v8::Value> callback_function = handle->Get(Nan::New<v8::String>("callback_data").ToLocalChecked());
		if(callback_function.IsEmpty() || callback_function->IsNullOrUndefined() || !callback_function->IsFunction()) {
			lock_guard lock(this->_data_lock);
			this->_data_entries.clear();
		}

		std::unique_ptr<DataEntry> buffer;
		while(true) {
			{
				lock_guard lock(this->_data_lock);
				if(this->_data_entries.empty())
					break;
				buffer = move(this->_data_entries.front());
				this->_data_entries.pop_front();
			}

			const auto byte_length = buffer->sample_count * this->_handle->channel_count * 4;
			auto js_buffer = v8::ArrayBuffer::New(Nan::GetCurrentContext()->GetIsolate(), byte_length);
			auto js_fbuffer = v8::Float32Array::New(js_buffer, 0, byte_length / 4);

			memcpy(js_buffer->GetContents().Data(), buffer->buffer, byte_length);

			v8::Local<v8::Value> argv[1];
			argv[0] = js_fbuffer;
			callback_function.As<v8::Function>()->Call(Nan::GetCurrentContext(), Nan::Undefined(), 1, argv);
		}
	});

	this->_call_ended = Nan::async_callback([&]{
		Nan::HandleScope scope;

		auto handle = this->handle();
		v8::Local<v8::Value> callback_function = handle->Get(Nan::New<v8::String>("callback_ended").ToLocalChecked());
		if(callback_function.IsEmpty() || callback_function->IsNullOrUndefined() || !callback_function->IsFunction())
			return;
		callback_function.As<v8::Function>()->Call(Nan::GetCurrentContext(), Nan::Undefined(), 0, nullptr);
	});

	this->_call_started = Nan::async_callback([&]{
		Nan::HandleScope scope;

		auto handle = this->handle();
		v8::Local<v8::Value> callback_function = handle->Get(Nan::New<v8::String>("callback_started").ToLocalChecked());
		if(callback_function.IsEmpty() || callback_function->IsNullOrUndefined() || !callback_function->IsFunction())
			return;
		callback_function.As<v8::Function>()->Call(Nan::GetCurrentContext(), Nan::Undefined(), 0, nullptr);
	});

	Nan::Set(this->handle(), Nan::New<v8::String>("frame_size").ToLocalChecked(), Nan::New<v8::Number>(this->_handle->frame_size));
	Nan::Set(this->handle(), Nan::New<v8::String>("sample_rate").ToLocalChecked(), Nan::New<v8::Number>(this->_handle->sample_rate));
	Nan::Set(this->handle(), Nan::New<v8::String>("channels").ToLocalChecked(), Nan::New<v8::Number>(this->_handle->channel_count));
}

void AudioConsumerWrapper::unbind() {
	if(this->_handle) {
		lock_guard lock(this->_handle->on_read_lock);
		this->_handle->on_read = nullptr;
	}
}

void AudioConsumerWrapper::process_data(const void *buffer, size_t samples) {
	lock_guard lock(this->execute_lock);

	auto filters = this->filters();
	for(const auto& filter : filters) {
		auto _filter = filter->filter();
		if(!_filter) continue;

		if(_filter->frame_size() != samples) {
			cerr << "Tried to use a filter, but frame size does not match!" << endl;
			continue;
		}
		if(!_filter->process(buffer)) {
			if(!this->last_consumed) {
				this->last_consumed = true;
				this->_call_ended();
				unique_lock native_read_lock(this->native_read_callback_lock);
				if(this->native_read_callback) {
					auto callback = this->native_read_callback; /* copy */
					native_read_lock.unlock();
					callback(nullptr, 0); /* notify end */
				}
			}
			return;
		}
	}

	if(this->last_consumed)
		this->_call_started();
	this->last_consumed = false;

	{
		unique_lock native_read_lock(this->native_read_callback_lock);
		if(this->native_read_callback) {
			auto callback = this->native_read_callback; /* copy */
			native_read_lock.unlock();

			callback(buffer, samples);
			return;
		}
	}

	auto byte_length = samples * this->_handle->channel_count * 4;
	auto buf = make_unique<DataEntry>();
	buf->buffer = malloc(byte_length);
	memcpy(buf->buffer, buffer, byte_length);
	buf->sample_count = samples;

	{
		lock_guard lock(this->_data_lock);
		this->_data_entries.push_back(move(buf));
	}
	this->_call_data();
}



std::shared_ptr<AudioFilterWrapper> AudioConsumerWrapper::create_filter(const std::string& name, const std::shared_ptr<filter::Filter> &impl) {
	auto result = shared_ptr<AudioFilterWrapper>(new AudioFilterWrapper(name, impl), [](AudioFilterWrapper* ptr) {
		assert(v8::Isolate::GetCurrent());
		ptr->Unref();
	});

	/* wrap into object */
	{
		auto js_object = Nan::NewInstance(Nan::New(AudioFilterWrapper::constructor()), 0, nullptr).ToLocalChecked();
		result->do_wrap(js_object);
		result->Ref();
	}

	{
		lock_guard lock(this->_filters_lock);
		this->_filters.push_back(result);
	}

	return result;
}

void AudioConsumerWrapper::delete_filter(const AudioFilterWrapper* filter) {
	shared_ptr<AudioFilterWrapper> handle; /* need to keep the handle 'till everything has been finished */
	{
		lock_guard lock(this->_filters_lock);
		for(auto& c : this->_filters) {
			if(&*c == filter) {
				handle = c;
				break;
			}
		}
		if(!handle)
			return;

		{
			auto it = find(this->_filters.begin(), this->_filters.end(), handle);
			if(it != this->_filters.end())
				this->_filters.erase(it);
		}
	}

	{
		lock_guard lock(this->execute_lock); /* ensure that the filter isn't used right now */
		handle->_filter = nullptr;
	}
}


NAN_METHOD(AudioConsumerWrapper::_get_filters) {
	auto handle = ObjectWrap::Unwrap<AudioConsumerWrapper>(info.Holder());
	auto filters = handle->filters();

	auto result = Nan::New<v8::Array>(filters.size());

	for(size_t index = 0; index < filters.size(); index++)
		result->Set(index, filters[index]->handle());

	info.GetReturnValue().Set(result);
}

NAN_METHOD(AudioConsumerWrapper::_unregister_filter) {
	auto handle = ObjectWrap::Unwrap<AudioConsumerWrapper>(info.Holder());

	if(info.Length() != 1 || !info[0]->IsObject()) {
		Nan::ThrowError("invalid argument");
		return;
	}

	if(!Nan::New(AudioFilterWrapper::constructor_template())->HasInstance(info[0])) {
		Nan::ThrowError("invalid consumer");
		return;
	}

	auto consumer = ObjectWrap::Unwrap<AudioFilterWrapper>(info[0]->ToObject(Nan::GetCurrentContext()).ToLocalChecked());
	handle->delete_filter(consumer);
}


NAN_METHOD(AudioConsumerWrapper::_create_filter_vad) {
	auto handle = ObjectWrap::Unwrap<AudioConsumerWrapper>(info.Holder());
	auto consumer = handle->_handle;
	assert(consumer); /* should never be null! */

	if(info.Length() != 1 || !info[0]->IsNumber()) {
		Nan::ThrowError("invalid argument");
		return;
	}

	string error;
	auto filter = make_shared<filter::VadFilter>(consumer->channel_count,consumer->sample_rate,consumer->frame_size);
	if(!filter->initialize(error, info[0]->Int32Value(Nan::GetCurrentContext()).FromMaybe(0), 2)) {
		Nan::ThrowError(Nan::New<v8::String>("failed to initialize filter (" + error + ")").ToLocalChecked());
		return;
	}

	auto object = handle->create_filter("vad", filter);
	info.GetReturnValue().Set(object->handle());
}

NAN_METHOD(AudioConsumerWrapper::_create_filter_threshold) {
	auto handle = ObjectWrap::Unwrap<AudioConsumerWrapper>(info.Holder());
	auto consumer = handle->_handle;
	assert(consumer); /* should never be null! */

	if(info.Length() != 1 || !info[0]->IsNumber()) {
		Nan::ThrowError("invalid argument");
		return;
	}

	string error;
	auto filter = make_shared<filter::ThresholdFilter>(consumer->channel_count,consumer->sample_rate,consumer->frame_size);
	if(!filter->initialize(error, info[0]->Int32Value(Nan::GetCurrentContext()).FromMaybe(0), 2)) {
		Nan::ThrowError(Nan::New<v8::String>("failed to initialize filter (" + error + ")").ToLocalChecked());
		return;
	}

	auto object = handle->create_filter("threshold", filter);
	info.GetReturnValue().Set(object->handle());
}

NAN_METHOD(AudioConsumerWrapper::_create_filter_state) {
	auto handle = ObjectWrap::Unwrap<AudioConsumerWrapper>(info.Holder());
	auto consumer = handle->_handle;
	assert(consumer); /* should never be null! */

	string error;
	auto filter = make_shared<filter::StateFilter>(consumer->channel_count,consumer->sample_rate,consumer->frame_size);
	if(!filter->initialize(error)) {
		Nan::ThrowError(Nan::New<v8::String>("failed to initialize filter (" + error + ")").ToLocalChecked());
		return;
	}

	auto object = handle->create_filter("state", filter);
	info.GetReturnValue().Set(object->handle());
}