/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include <stdbool.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <syslog.h>

#include "cras_audio_area.h"
#include "cras_hfp_ag_profile.h"
#include "cras_hfp_iodev.h"
#include "cras_hfp_info.h"
#include "cras_hfp_slc.h"
#include "cras_iodev.h"
#include "cras_system_state.h"
#include "cras_util.h"
#include "utlist.h"

/* Implementation of bluetooth hands-free profile iodev.
 * Members:
 *    base - The cras_iodev structure base class.
 *    device - The assciated bt_device.
 *    slc - Handle to the HFP service level connection.
 *    info - hfp_info taking care of SCO data read/write.
 *    drain_complete - Flag to indicate if valid samples are drained
 *        in no stream state. Only used for output.
 *    filled_zeros - Number of zero data in frames have been filled
 *        to buffer of hfp_info in no stream state. Only used for output
 */
struct hfp_io {
	struct cras_iodev base;
	struct cras_bt_device *device;
	struct hfp_slc_handle *slc;
	struct hfp_info *info;
	bool drain_complete;
	unsigned int filled_zeros;
};

static int update_supported_formats(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	free(iodev->supported_rates);
	iodev->supported_rates = (size_t *)malloc(2 * sizeof(size_t));

	/* 16 bit, mono, 8kHz for narrowband and 16KHz for wideband */
	iodev->supported_rates[0] =
		(hfp_slc_get_selected_codec(hfpio->slc) == HFP_CODEC_ID_MSBC) ?
			16000 :
			8000;
	iodev->supported_rates[1] = 0;

	free(iodev->supported_channel_counts);
	iodev->supported_channel_counts = (size_t *)malloc(2 * sizeof(size_t));
	iodev->supported_channel_counts[0] = 1;
	iodev->supported_channel_counts[1] = 0;

	free(iodev->supported_formats);
	iodev->supported_formats =
		(snd_pcm_format_t *)malloc(2 * sizeof(snd_pcm_format_t));
	iodev->supported_formats[0] = SND_PCM_FORMAT_S16_LE;
	iodev->supported_formats[1] = 0;

	return 0;
}

static int no_stream(struct cras_iodev *iodev, int enable)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;
	struct timespec hw_tstamp;
	unsigned int hw_level;
	unsigned int level_target;

	if (iodev->direction != CRAS_STREAM_OUTPUT)
		return 0;

	hw_level = iodev->frames_queued(iodev, &hw_tstamp);
	if (enable) {
		if (!hfpio->drain_complete && (hw_level <= hfpio->filled_zeros))
			hfpio->drain_complete = 1;
		hfpio->filled_zeros += hfp_fill_output_with_zeros(
			hfpio->info, iodev->buffer_size);
		return 0;
	}

	/* Leave no stream state.*/
	level_target = iodev->min_cb_level;
	if (hfpio->drain_complete) {
		hfp_force_output_level(hfpio->info, level_target);
	} else {
		unsigned int valid_samples = 0;
		if (hw_level > hfpio->filled_zeros)
			valid_samples = hw_level - hfpio->filled_zeros;
		level_target = MAX(level_target, valid_samples);

		if (level_target > hw_level)
			hfp_fill_output_with_zeros(hfpio->info,
						   level_target - hw_level);
		else
			hfp_force_output_level(hfpio->info, level_target);
	}
	hfpio->drain_complete = 0;
	hfpio->filled_zeros = 0;

	return 0;
}

static int frames_queued(const struct cras_iodev *iodev,
			 struct timespec *tstamp)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	if (!hfp_info_running(hfpio->info))
		return -1;

	/* Do not enable timestamp mechanism on HFP device because last time
	 * stamp might be a long time ago and it is not really useful. */
	clock_gettime(CLOCK_MONOTONIC_RAW, tstamp);
	return hfp_buf_queued(hfpio->info, iodev->direction);
}

static int output_underrun(struct cras_iodev *iodev)
{
	/* Handle it the same way as cras_iodev_output_underrun(). */
	return cras_iodev_fill_odev_zeros(iodev, iodev->min_cb_level);
}

static int configure_dev(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;
	int sk, err, mtu;

	/* Assert format is set before opening device. */
	if (iodev->format == NULL)
		return -EINVAL;

	iodev->format->format = SND_PCM_FORMAT_S16_LE;
	cras_iodev_init_audio_area(iodev, iodev->format->num_channels);

	if (hfp_info_running(hfpio->info))
		goto add_dev;

	/*
	 * Might require a codec negotiation before building the sco connection.
	 */
	hfp_slc_codec_connection_setup(hfpio->slc);

	sk = cras_bt_device_sco_connect(hfpio->device,
					hfp_slc_get_selected_codec(hfpio->slc));
	if (sk < 0)
		goto error;

	mtu = cras_bt_device_sco_packet_size(
		hfpio->device, sk, hfp_slc_get_selected_codec(hfpio->slc));

	/* Start hfp_info */
	err = hfp_info_start(sk, mtu, hfp_slc_get_selected_codec(hfpio->slc),
			     hfpio->info);
	if (err)
		goto error;

	hfpio->drain_complete = 0;
	hfpio->filled_zeros = 0;
add_dev:
	hfp_info_add_iodev(hfpio->info, iodev->direction, iodev->format);
	hfp_set_call_status(hfpio->slc, 1);

	iodev->buffer_size = hfp_buf_size(hfpio->info, iodev->direction);

	return 0;
error:
	syslog(LOG_ERR, "Failed to open HFP iodev");
	return -1;
}

static int close_dev(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	hfp_info_rm_iodev(hfpio->info, iodev->direction);
	if (hfp_info_running(hfpio->info) && !hfp_info_has_iodev(hfpio->info)) {
		hfp_info_stop(hfpio->info);
		hfp_set_call_status(hfpio->slc, 0);
	}

	cras_iodev_free_format(iodev);
	cras_iodev_free_audio_area(iodev);
	return 0;
}

static void set_hfp_volume(struct cras_iodev *iodev)
{
	size_t volume;
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	volume = cras_system_get_volume();
	if (iodev->active_node)
		volume = cras_iodev_adjust_node_volume(iodev->active_node,
						       volume);

	hfp_event_speaker_gain(hfpio->slc, volume);
}

static int delay_frames(const struct cras_iodev *iodev)
{
	struct timespec tstamp;

	return frames_queued(iodev, &tstamp);
}

static int get_buffer(struct cras_iodev *iodev, struct cras_audio_area **area,
		      unsigned *frames)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;
	uint8_t *dst = NULL;

	if (!hfp_info_running(hfpio->info))
		return -1;

	hfp_buf_acquire(hfpio->info, iodev->direction, &dst, frames);

	iodev->area->frames = *frames;
	/* HFP is mono only. */
	iodev->area->channels[0].step_bytes =
		cras_get_format_bytes(iodev->format);
	iodev->area->channels[0].buf = dst;

	*area = iodev->area;
	return 0;
}

static int put_buffer(struct cras_iodev *iodev, unsigned nwritten)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	if (!hfp_info_running(hfpio->info))
		return -1;

	hfp_buf_release(hfpio->info, iodev->direction, nwritten);
	return 0;
}

static int flush_buffer(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;
	unsigned nframes;

	if (iodev->direction == CRAS_STREAM_INPUT) {
		nframes = hfp_buf_queued(hfpio->info, iodev->direction);
		hfp_buf_release(hfpio->info, iodev->direction, nframes);
	}
	return 0;
}

static void update_active_node(struct cras_iodev *iodev, unsigned node_idx,
			       unsigned dev_enabled)
{
}

int hfp_iodev_is_hsp(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;
	return hfp_slc_is_hsp(hfpio->slc);
}

void hfp_free_resources(struct hfp_io *hfpio)
{
	struct cras_ionode *node;
	node = hfpio->base.active_node;
	if (node) {
		cras_iodev_rm_node(&hfpio->base, node);
		free(node);
	}
	free(hfpio->base.supported_channel_counts);
	free(hfpio->base.supported_rates);
	free(hfpio->base.supported_formats);
	cras_iodev_free_resources(&hfpio->base);
}

struct cras_iodev *hfp_iodev_create(enum CRAS_STREAM_DIRECTION dir,
				    struct cras_bt_device *device,
				    struct hfp_slc_handle *slc,
				    enum cras_bt_device_profile profile,
				    struct hfp_info *info)
{
	struct hfp_io *hfpio;
	struct cras_iodev *iodev;
	struct cras_ionode *node;
	const char *name;

	hfpio = (struct hfp_io *)calloc(1, sizeof(*hfpio));
	if (!hfpio)
		goto error;

	iodev = &hfpio->base;
	iodev->direction = dir;

	hfpio->device = device;
	hfpio->slc = slc;

	/* Set iodev's name to device readable name or the address. */
	name = cras_bt_device_name(device);
	if (!name)
		name = cras_bt_device_object_path(device);

	snprintf(iodev->info.name, sizeof(iodev->info.name), "%s", name);
	iodev->info.name[ARRAY_SIZE(iodev->info.name) - 1] = 0;
	iodev->info.stable_id = cras_bt_device_get_stable_id(device);

	iodev->configure_dev = configure_dev;
	iodev->frames_queued = frames_queued;
	iodev->delay_frames = delay_frames;
	iodev->get_buffer = get_buffer;
	iodev->put_buffer = put_buffer;
	iodev->flush_buffer = flush_buffer;
	iodev->no_stream = no_stream;
	iodev->close_dev = close_dev;
	iodev->update_supported_formats = update_supported_formats;
	iodev->update_active_node = update_active_node;
	iodev->set_volume = set_hfp_volume;
	iodev->output_underrun = output_underrun;

	node = (struct cras_ionode *)calloc(1, sizeof(*node));
	node->dev = iodev;
	strcpy(node->name, iodev->info.name);

	node->plugged = 1;
	/* If headset mic doesn't support the wideband speech, report a
	 * different node type so UI can set different plug priority. */
	node->type = CRAS_NODE_TYPE_BLUETOOTH;
	if (!hfp_slc_get_wideband_speech_supported(hfpio->slc) &&
	    (dir == CRAS_STREAM_INPUT))
		node->type = CRAS_NODE_TYPE_BLUETOOTH_NB_MIC;

	node->volume = 100;
	gettimeofday(&node->plugged_time, NULL);

	/* Prepare active node before append, so bt_io can extract correct
	 * info from HFP iodev and node. */
	cras_iodev_add_node(iodev, node);
	cras_iodev_set_active_node(iodev, node);
	cras_bt_device_append_iodev(device, iodev, profile);

	hfpio->info = info;

	/* Record max supported channels into cras_iodev_info. */
	iodev->info.max_supported_channels = 1;

	ewma_power_disable(&iodev->ewma);

	return iodev;

error:
	if (hfpio) {
		hfp_free_resources(hfpio);
		free(hfpio);
	}
	return NULL;
}

void hfp_iodev_destroy(struct cras_iodev *iodev)
{
	struct hfp_io *hfpio = (struct hfp_io *)iodev;

	cras_bt_device_rm_iodev(hfpio->device, iodev);
	hfp_free_resources(hfpio);
	free(hfpio);
}