/* 
 *  Squeezelite - lightweight headless squeezebox emulator
 *
 *  (c) Adrian Smith 2012-2015, triode1@btinternet.com
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

// Portaudio output

#include "squeezelite.h"

#if PORTAUDIO

#include <portaudio.h>
#if OSX
#include <pa_mac_core.h>
#endif

// ouput device
static struct {
	unsigned rate;
	PaStream *stream;
} pa;

static log_level loglevel;

static bool running = true;

extern struct outputstate output;
extern struct buffer *outputbuf;

#define LOCK   mutex_lock(outputbuf->mutex)
#define UNLOCK mutex_unlock(outputbuf->mutex)

extern u8_t *silencebuf;
#if DSD
extern u8_t *silencebuf_dop;
#endif

void list_devices(void) {
	PaError err;
	int i;

	if ((err = Pa_Initialize()) != paNoError) {
		LOG_WARN("error initialising port audio: %s", Pa_GetErrorText(err));
		return;
	}
	
	printf("Output devices:\n");
	for (i = 0; i < Pa_GetDeviceCount(); ++i) {
		if (Pa_GetDeviceInfo(i)->maxOutputChannels) {
			printf("  %i - %s [%s]\n", i, Pa_GetDeviceInfo(i)->name, Pa_GetHostApiInfo(Pa_GetDeviceInfo(i)->hostApi)->name);
		}
	}
	printf("\n");
	
	if ((err = Pa_Terminate()) != paNoError) {
		LOG_WARN("error closing port audio: %s", Pa_GetErrorText(err));
	}
}

void set_volume(unsigned left, unsigned right) {
	LOG_DEBUG("setting internal gain left: %u right: %u", left, right);
	LOCK;
	output.gainL = left;
	output.gainR = right;
	UNLOCK;
}

static int pa_device_id(const char *device) {
	int len = strlen(device);
	int i;

	if (!strncmp(device, "default", 7)) {
		return Pa_GetDefaultOutputDevice();
	}
	if (len >= 1 && len <= 2 && device[0] >= '0' && device[0] <= '9') {
		return atoi(device);
	}

#define DEVICE_ID_MAXLEN 256
	for (i = 0; i < Pa_GetDeviceCount(); ++i) {
		char tmp[DEVICE_ID_MAXLEN];
		snprintf(tmp, DEVICE_ID_MAXLEN, "%s [%s]", Pa_GetDeviceInfo(i)->name, Pa_GetHostApiInfo(Pa_GetDeviceInfo(i)->hostApi)->name);
		if (!strncmp(tmp, device, len)) {
			return i;
		}
	}

	return -1;
}

static int pa_callback(const void *pa_input, void *pa_output, unsigned long pa_frames_wanted, 
					   const PaStreamCallbackTimeInfo *timeInfo, PaStreamCallbackFlags statusFlags, void *userData);

bool test_open(const char *device, unsigned rates[]) {
	PaStreamParameters outputParameters;
	PaError err;
	unsigned ref[] TEST_RATES;
	int device_id, i, ind;

	if ((device_id = pa_device_id(device)) == -1) {
		LOG_INFO("device %s not found", device);
		return false;
	}

	outputParameters.device = device_id;
	outputParameters.channelCount = 2;
	outputParameters.sampleFormat = paInt32;
	outputParameters.suggestedLatency =
		output.latency ? (double)output.latency/(double)1000 : Pa_GetDeviceInfo(outputParameters.device)->defaultHighOutputLatency;
	outputParameters.hostApiSpecificStreamInfo = NULL;

	// check supported sample rates
	// Note use Pa_OpenStream as it appears more reliable than Pa_IsFormatSupported on some windows apis
	for (i = 0, ind = 0; ref[i]; ++i) {
		err = Pa_OpenStream(&pa.stream, NULL, &outputParameters, (double)ref[i], paFramesPerBufferUnspecified, paNoFlag, 
							pa_callback, NULL);
		if (err == paNoError) {
			Pa_CloseStream(pa.stream);
			rates[ind++] = ref[i];
		}
	}

	if (!rates[0]) {
		LOG_WARN("no available rate found");
		return false;
	}

	pa.stream = NULL;
	return true;
}

static void pa_stream_finished(void *userdata) {
	if (running) {
		LOG_INFO("stream finished");
		LOCK;
		output.pa_reopen = true;
		wake_controller();
		UNLOCK;
	}
}

static thread_type monitor_thread;
bool monitor_thread_running = false;

static void *pa_monitor() {
	bool output_off;

	LOCK;

	if (monitor_thread_running) {
		LOG_DEBUG("monitor thread already running");
		UNLOCK;
		return 0;
	}

	LOG_DEBUG("start monitor thread");

	monitor_thread_running = true;
	output_off = (output.state == OUTPUT_OFF);

	while (monitor_thread_running) {
		if (output_off) {
			if (output.state != OUTPUT_OFF) {
				LOG_INFO("output on");
				break;
			}
		} else {
			// this is a hack to partially support hot plugging of devices
			// we rely on terminating and reinitalising PA to get an updated list of devices and use name for output.device
			LOG_INFO("probing device %s", output.device);
			Pa_Terminate();
			Pa_Initialize();
			pa.stream = NULL;
			if (pa_device_id(output.device) != -1) {
				LOG_INFO("device reopen");
				break;
			}
		}

		UNLOCK;
		sleep(output_off ? 1 : 5);
		LOCK;
	}

	LOG_DEBUG("end monitor thread");

	monitor_thread_running = false;
	pa.stream = NULL;

	_pa_open();

	UNLOCK;

	return 0;
}

void _pa_open(void) {
	PaStreamParameters outputParameters;
	PaError err = paNoError;
	int device_id;

	if (pa.stream) {
		if ((err = Pa_CloseStream(pa.stream)) != paNoError) {
			LOG_WARN("error closing stream: %s", Pa_GetErrorText(err));
		}
	}

	if (output.state == OUTPUT_OFF) {
		// we get called when transitioning to OUTPUT_OFF to create the probe thread
		// set err to avoid opening device and logging messages
		err = 1;

	} else if ((device_id = pa_device_id(output.device)) == -1) {
		LOG_INFO("device %s not found", output.device);
		err = 1;

	} else {

		outputParameters.device = device_id;
		outputParameters.channelCount = 2;
		outputParameters.sampleFormat = paInt32;
		outputParameters.suggestedLatency =
			output.latency ? (double)output.latency/(double)1000 : Pa_GetDeviceInfo(outputParameters.device)->defaultHighOutputLatency;
		outputParameters.hostApiSpecificStreamInfo = NULL;
		
#if OSX
		// enable pro mode which aims to avoid resampling if possible
		// see http://code.google.com/p/squeezelite/issues/detail?id=11 & http://code.google.com/p/squeezelite/issues/detail?id=37
		// command line controls osx_playnice which is -1 if not specified, 0 or 1 - choose playnice if -1 or 1
		PaMacCoreStreamInfo macInfo;
		unsigned long streamInfoFlags;
	 	if (output.osx_playnice) {
			LOG_INFO("opening device in PlayNice mode");
			streamInfoFlags = paMacCorePlayNice;
		} else {
			LOG_INFO("opening device in Pro mode");
			streamInfoFlags = paMacCorePro;
		}
		PaMacCore_SetupStreamInfo(&macInfo, streamInfoFlags);
		outputParameters.hostApiSpecificStreamInfo = &macInfo;
#endif
	}

	if (!err &&
		(err = Pa_OpenStream(&pa.stream, NULL, &outputParameters, (double)output.current_sample_rate, paFramesPerBufferUnspecified,
							 paPrimeOutputBuffersUsingStreamCallback | paDitherOff, pa_callback, NULL)) != paNoError) {
		LOG_WARN("error opening device %i - %s : %s", outputParameters.device, Pa_GetDeviceInfo(outputParameters.device)->name, 
				 Pa_GetErrorText(err));
	}

	if (!err) {
		LOG_INFO("opened device %i - %s at %u latency %u ms", outputParameters.device, Pa_GetDeviceInfo(outputParameters.device)->name,
				 (unsigned int)Pa_GetStreamInfo(pa.stream)->sampleRate, (unsigned int)(Pa_GetStreamInfo(pa.stream)->outputLatency * 1000));

		pa.rate = output.current_sample_rate;

		if ((err = Pa_SetStreamFinishedCallback(pa.stream, pa_stream_finished)) != paNoError) {
			LOG_WARN("error setting finish callback: %s", Pa_GetErrorText(err));
		}
	
		UNLOCK; // StartStream can call pa_callback in a sychronised thread on freebsd, remove lock while it is called

		if ((err = Pa_StartStream(pa.stream)) != paNoError) {
			LOG_WARN("error starting stream: %s", Pa_GetErrorText(err));
		}

		LOCK;
	}

	if (err && !monitor_thread_running) {
		vis_stop();

		// create a thread to check for output state change or device return
#if LINUX || OSX || FREEBSD
		pthread_create(&monitor_thread, NULL, pa_monitor, NULL);
#endif
#if WIN
		monitor_thread = CreateThread(NULL, OUTPUT_THREAD_STACK_SIZE, (LPTHREAD_START_ROUTINE)&pa_monitor, NULL, 0, NULL);
#endif
	}

	output.error_opening = !!err;
}

static u8_t *optr;

static int _write_frames(frames_t out_frames, bool silence, s32_t gainL, s32_t gainR,
						 s32_t cross_gain_in, s32_t cross_gain_out, s32_t **cross_ptr) {
	
	if (!silence) {
		
		if (output.fade == FADE_ACTIVE && output.fade_dir == FADE_CROSS && *cross_ptr) {
			_apply_cross(outputbuf, out_frames, cross_gain_in, cross_gain_out, cross_ptr);
		}
		
		if (gainL != FIXED_ONE || gainR!= FIXED_ONE) {
			_apply_gain(outputbuf, out_frames, gainL, gainR);
		}

		IF_DSD(
			if (output.dop) {
				update_dop((u32_t *) outputbuf->readp, out_frames, output.invert);
			}
		)

		memcpy(optr, outputbuf->readp, out_frames * BYTES_PER_FRAME);

	} else {

		u8_t *buf = silencebuf;

		IF_DSD(
			if (output.dop) {
				buf = silencebuf_dop;
				update_dop((u32_t *) buf, out_frames, false); // don't invert silence
			}
		)

		memcpy(optr, buf, out_frames * BYTES_PER_FRAME);
	}
	
	optr += out_frames * BYTES_PER_FRAME;

	return (int)out_frames;
}

static int pa_callback(const void *pa_input, void *pa_output, unsigned long pa_frames_wanted, 
					   const PaStreamCallbackTimeInfo *time_info, PaStreamCallbackFlags statusFlags, void *userData) {
	int ret;
	double stream_time;
	frames_t frames;

	optr = (u8_t *)pa_output;

	LOCK;

	stream_time = Pa_GetStreamTime(pa.stream);

	if (time_info->outputBufferDacTime > stream_time) {
		// workaround for wdm-ks which can return outputBufferDacTime with a different epoch
		output.device_frames = (unsigned)((time_info->outputBufferDacTime - stream_time) * output.current_sample_rate);
	} else {
		output.device_frames = 0;
	}

	output.updated = gettime_ms();
	output.frames_played_dmp = output.frames_played;

	do {
		frames = _output_frames(pa_frames_wanted);
		pa_frames_wanted -= frames;
	} while (pa_frames_wanted > 0 && frames != 0);

	if (pa_frames_wanted > 0) {
		LOG_DEBUG("pad with silence");
		memset(optr, 0, pa_frames_wanted * BYTES_PER_FRAME);
	}

	if (output.state == OUTPUT_OFF) {
		LOG_INFO("output off");
		ret = paComplete;
	} else if (pa.rate != output.current_sample_rate) {
		ret = paComplete;
	} else {
		ret = paContinue;
	}

	UNLOCK;

	return ret;
}

void output_init_pa(log_level level, const char *device, unsigned output_buf_size, char *params, unsigned rates[], unsigned rate_delay,
					unsigned idle) {
	PaError err;
	unsigned latency = 0;
	int osx_playnice = -1;

	char *l = next_param(params, ':');
	char *p = next_param(NULL, ':');

	if (l) latency = (unsigned)atoi(l);
	if (p) osx_playnice = atoi(p);

	loglevel = level;

	LOG_INFO("init output");

	memset(&output, 0, sizeof(output));

	output.latency = latency;
	output.osx_playnice = osx_playnice;
	output.format = 0;
	output.start_frames = 0;
	output.write_cb = &_write_frames;
	output.rate_delay = rate_delay;
	pa.stream = NULL;

	LOG_INFO("requested latency: %u", output.latency);

	if ((err = Pa_Initialize()) != paNoError) {
		LOG_WARN("error initialising port audio: %s", Pa_GetErrorText(err));
		exit(0);
	}

	output_init_common(level, device, output_buf_size, rates, idle);

	LOCK;

	_pa_open();

	UNLOCK;
}

void output_close_pa(void) {
	PaError err;

	LOG_INFO("close output");

	LOCK;

	running = false;
	monitor_thread_running = false;

	if (pa.stream) {
		if ((err = Pa_AbortStream(pa.stream)) != paNoError) {
			LOG_WARN("error closing stream: %s", Pa_GetErrorText(err));
		}
	}

	if ((err = Pa_Terminate()) != paNoError) {
		LOG_WARN("error closing port audio: %s", Pa_GetErrorText(err));
	}

	UNLOCK;

	output_close_common();
}

#endif // PORTAUDIO