/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Video Redirection Virtual Channel - PulseAudio Device
 *
 * Copyright 2010-2011 Vic Lee
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <freerdp/config.h>
#include <freerdp/utils/helpers.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <winpr/crt.h>

#include <pulse/pulseaudio.h>

#include "tsmf_audio.h"

typedef struct
{
	ITSMFAudioDevice iface;

	char device[32];
	pa_threaded_mainloop* mainloop;
	pa_context* context;
	pa_sample_spec sample_spec;
	pa_stream* stream;
} TSMFPulseAudioDevice;

static void tsmf_pulse_context_state_callback(pa_context* context, void* userdata)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)userdata;
	pa_context_state_t state = pa_context_get_state(context);

	switch (state)
	{
		case PA_CONTEXT_READY:
			DEBUG_TSMF("PA_CONTEXT_READY");
			pa_threaded_mainloop_signal(pulse->mainloop, 0);
			break;

		case PA_CONTEXT_FAILED:
		case PA_CONTEXT_TERMINATED:
			DEBUG_TSMF("state %d", state);
			pa_threaded_mainloop_signal(pulse->mainloop, 0);
			break;

		default:
			DEBUG_TSMF("state %d", state);
			break;
	}
}

static BOOL tsmf_pulse_connect(TSMFPulseAudioDevice* pulse)
{
	pa_context_state_t state = PA_CONTEXT_FAILED;

	if (!pulse->context)
		return FALSE;

	if (pa_context_connect(pulse->context, nullptr, 0, nullptr))
	{
		WLog_ERR(TAG, "pa_context_connect failed (%d)", pa_context_errno(pulse->context));
		return FALSE;
	}

	pa_threaded_mainloop_lock(pulse->mainloop);

	if (pa_threaded_mainloop_start(pulse->mainloop) < 0)
	{
		pa_threaded_mainloop_unlock(pulse->mainloop);
		WLog_ERR(TAG, "pa_threaded_mainloop_start failed (%d)", pa_context_errno(pulse->context));
		return FALSE;
	}

	for (;;)
	{
		state = pa_context_get_state(pulse->context);

		if (state == PA_CONTEXT_READY)
			break;

		if (!PA_CONTEXT_IS_GOOD(state))
		{
			DEBUG_TSMF("bad context state (%d)", pa_context_errno(pulse->context));
			break;
		}

		pa_threaded_mainloop_wait(pulse->mainloop);
	}

	pa_threaded_mainloop_unlock(pulse->mainloop);

	if (state == PA_CONTEXT_READY)
	{
		DEBUG_TSMF("connected");
		return TRUE;
	}
	else
	{
		pa_context_disconnect(pulse->context);
		return FALSE;
	}
}

static BOOL tsmf_pulse_open(ITSMFAudioDevice* audio, const char* device)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;

	if (device)
	{
		strncpy(pulse->device, device, sizeof(pulse->device) - 1);
	}

	pulse->mainloop = pa_threaded_mainloop_new();

	if (!pulse->mainloop)
	{
		WLog_ERR(TAG, "pa_threaded_mainloop_new failed");
		return FALSE;
	}

	pulse->context = pa_context_new(pa_threaded_mainloop_get_api(pulse->mainloop),
	                                freerdp_getApplicationDetailsString());

	if (!pulse->context)
	{
		WLog_ERR(TAG, "pa_context_new failed");
		return FALSE;
	}

	pa_context_set_state_callback(pulse->context, tsmf_pulse_context_state_callback, pulse);

	if (!tsmf_pulse_connect(pulse))
	{
		WLog_ERR(TAG, "tsmf_pulse_connect failed");
		return FALSE;
	}

	DEBUG_TSMF("open device %s", pulse->device);
	return TRUE;
}

static void tsmf_pulse_stream_success_callback(WINPR_ATTR_UNUSED pa_stream* stream,
                                               WINPR_ATTR_UNUSED int success, void* userdata)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)userdata;
	pa_threaded_mainloop_signal(pulse->mainloop, 0);
}

static void tsmf_pulse_wait_for_operation(TSMFPulseAudioDevice* pulse, pa_operation* operation)
{
	if (operation == nullptr)
		return;

	while (pa_operation_get_state(operation) == PA_OPERATION_RUNNING)
	{
		pa_threaded_mainloop_wait(pulse->mainloop);
	}

	pa_operation_unref(operation);
}

static void tsmf_pulse_stream_state_callback(pa_stream* stream, void* userdata)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)userdata;
	WINPR_ASSERT(pulse);

	pa_stream_state_t state = pa_stream_get_state(stream);

	switch (state)
	{
		case PA_STREAM_READY:
			DEBUG_TSMF("PA_STREAM_READY");
			pa_threaded_mainloop_signal(pulse->mainloop, 0);
			break;

		case PA_STREAM_FAILED:
		case PA_STREAM_TERMINATED:
			DEBUG_TSMF("state %d", state);
			pa_threaded_mainloop_signal(pulse->mainloop, 0);
			break;

		default:
			DEBUG_TSMF("state %d", state);
			break;
	}
}

static void tsmf_pulse_stream_request_callback(WINPR_ATTR_UNUSED pa_stream* stream,
                                               WINPR_ATTR_UNUSED size_t length, void* userdata)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)userdata;
	DEBUG_TSMF("%" PRIdz "", length);
	pa_threaded_mainloop_signal(pulse->mainloop, 0);
}

static BOOL tsmf_pulse_close_stream(TSMFPulseAudioDevice* pulse)
{
	if (!pulse->context || !pulse->stream)
		return FALSE;

	DEBUG_TSMF("");
	pa_threaded_mainloop_lock(pulse->mainloop);
	pa_stream_set_write_callback(pulse->stream, nullptr, nullptr);
	tsmf_pulse_wait_for_operation(
	    pulse, pa_stream_drain(pulse->stream, tsmf_pulse_stream_success_callback, pulse));
	pa_stream_disconnect(pulse->stream);
	pa_stream_unref(pulse->stream);
	pulse->stream = nullptr;
	pa_threaded_mainloop_unlock(pulse->mainloop);
	return TRUE;
}

static BOOL tsmf_pulse_open_stream(TSMFPulseAudioDevice* pulse)
{
	pa_stream_state_t state = PA_STREAM_FAILED;
	pa_buffer_attr buffer_attr = WINPR_C_ARRAY_INIT;

	if (!pulse->context)
		return FALSE;

	DEBUG_TSMF("");
	pa_threaded_mainloop_lock(pulse->mainloop);
	pulse->stream = pa_stream_new(pulse->context, freerdp_getApplicationDetailsString(),
	                              &pulse->sample_spec, nullptr);

	if (!pulse->stream)
	{
		pa_threaded_mainloop_unlock(pulse->mainloop);
		WLog_ERR(TAG, "pa_stream_new failed (%d)", pa_context_errno(pulse->context));
		return FALSE;
	}

	pa_stream_set_state_callback(pulse->stream, tsmf_pulse_stream_state_callback, pulse);
	pa_stream_set_write_callback(pulse->stream, tsmf_pulse_stream_request_callback, pulse);
	buffer_attr.maxlength = (uint32_t)pa_usec_to_bytes(500000, &pulse->sample_spec);
	buffer_attr.tlength = (uint32_t)pa_usec_to_bytes(250000, &pulse->sample_spec);
	buffer_attr.prebuf = (UINT32)-1;
	buffer_attr.minreq = (UINT32)-1;
	buffer_attr.fragsize = (UINT32)-1;

	if (pa_stream_connect_playback(
	        pulse->stream, pulse->device[0] ? pulse->device : nullptr, &buffer_attr,
	        PA_STREAM_ADJUST_LATENCY | PA_STREAM_INTERPOLATE_TIMING | PA_STREAM_AUTO_TIMING_UPDATE,
	        nullptr, nullptr) < 0)
	{
		pa_threaded_mainloop_unlock(pulse->mainloop);
		WLog_ERR(TAG, "pa_stream_connect_playback failed (%d)", pa_context_errno(pulse->context));
		return FALSE;
	}

	for (;;)
	{
		state = pa_stream_get_state(pulse->stream);

		if (state == PA_STREAM_READY)
			break;

		if (!PA_STREAM_IS_GOOD(state))
		{
			WLog_ERR(TAG, "bad stream state (%d)", pa_context_errno(pulse->context));
			break;
		}

		pa_threaded_mainloop_wait(pulse->mainloop);
	}

	pa_threaded_mainloop_unlock(pulse->mainloop);

	if (state == PA_STREAM_READY)
	{
		DEBUG_TSMF("connected");
		return TRUE;
	}
	else
	{
		tsmf_pulse_close_stream(pulse);
		return FALSE;
	}
}

static BOOL tsmf_pulse_set_format(ITSMFAudioDevice* audio, UINT32 sample_rate, UINT32 channels,
                                  WINPR_ATTR_UNUSED UINT32 bits_per_sample)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;
	DEBUG_TSMF("sample_rate %" PRIu32 " channels %" PRIu32 " bits_per_sample %" PRIu32 "",
	           sample_rate, channels, bits_per_sample);
	pulse->sample_spec.rate = sample_rate;

	WINPR_ASSERT(channels <= UINT8_MAX);
	pulse->sample_spec.channels = (uint8_t)channels;
	pulse->sample_spec.format = PA_SAMPLE_S16LE;
	return tsmf_pulse_open_stream(pulse);
}

static BOOL tsmf_pulse_play(ITSMFAudioDevice* audio, const BYTE* data, UINT32 data_size)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;
	const BYTE* src = nullptr;
	size_t len = 0;
	int ret = 0;
	DEBUG_TSMF("data_size %" PRIu32 "", data_size);

	if (pulse->stream)
	{
		pa_threaded_mainloop_lock(pulse->mainloop);
		src = data;

		while (data_size > 0)
		{
			while ((len = pa_stream_writable_size(pulse->stream)) == 0)
			{
				DEBUG_TSMF("waiting");
				pa_threaded_mainloop_wait(pulse->mainloop);
			}

			if (len == (size_t)-1)
				break;

			if (len > data_size)
				len = data_size;

			ret = pa_stream_write(pulse->stream, src, len, nullptr, 0LL, PA_SEEK_RELATIVE);

			if (ret < 0)
			{
				DEBUG_TSMF("pa_stream_write failed (%d)", pa_context_errno(pulse->context));
				break;
			}

			src += len;
			data_size -= len;
		}

		pa_threaded_mainloop_unlock(pulse->mainloop);
	}

	return TRUE;
}

static UINT64 tsmf_pulse_get_latency(ITSMFAudioDevice* audio)
{
	pa_usec_t usec = 0;
	UINT64 latency = 0;
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;

	if (pulse->stream && pa_stream_get_latency(pulse->stream, &usec, nullptr) == 0)
	{
		latency = ((UINT64)usec) * 10LL;
	}

	return latency;
}

static BOOL tsmf_pulse_flush(ITSMFAudioDevice* audio)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;
	pa_threaded_mainloop_lock(pulse->mainloop);
	tsmf_pulse_wait_for_operation(
	    pulse, pa_stream_flush(pulse->stream, tsmf_pulse_stream_success_callback, pulse));
	pa_threaded_mainloop_unlock(pulse->mainloop);
	return TRUE;
}

static void tsmf_pulse_free(ITSMFAudioDevice* audio)
{
	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)audio;
	DEBUG_TSMF("");
	tsmf_pulse_close_stream(pulse);

	if (pulse->mainloop)
	{
		pa_threaded_mainloop_stop(pulse->mainloop);
	}

	if (pulse->context)
	{
		pa_context_disconnect(pulse->context);
		pa_context_unref(pulse->context);
		pulse->context = nullptr;
	}

	if (pulse->mainloop)
	{
		pa_threaded_mainloop_free(pulse->mainloop);
		pulse->mainloop = nullptr;
	}

	free(pulse);
}

FREERDP_ENTRY_POINT(UINT VCAPITYPE pulse_freerdp_tsmf_client_audio_subsystem_entry(void* ptr))
{
	ITSMFAudioDevice** sptr = (ITSMFAudioDevice**)ptr;
	WINPR_ASSERT(sptr);
	*sptr = nullptr;

	TSMFPulseAudioDevice* pulse = (TSMFPulseAudioDevice*)calloc(1, sizeof(TSMFPulseAudioDevice));

	if (!pulse)
		return ERROR_OUTOFMEMORY;

	pulse->iface.Open = tsmf_pulse_open;
	pulse->iface.SetFormat = tsmf_pulse_set_format;
	pulse->iface.Play = tsmf_pulse_play;
	pulse->iface.GetLatency = tsmf_pulse_get_latency;
	pulse->iface.Flush = tsmf_pulse_flush;
	pulse->iface.Free = tsmf_pulse_free;
	*sptr = &pulse->iface;
	return CHANNEL_RC_OK;
}
