/* Copyright (C) 2006 Tim-Philipp Müller <tim centricular net>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the Free

 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

#include "gstalsa.h"

#include <gst/audio/multichannel.h>

static GstCaps *

gst_alsa_detect_rates (GstObject * obj, snd_pcm_hw_params_t * hw_params,

    GstCaps * in_caps)

{

  GstCaps *caps;

  guint min, max;

  gint err, dir, min_rate, max_rate, i;

  GST_LOG_OBJECT (obj, "probing sample rates ...");

  if ((err = snd_pcm_hw_params_get_rate_min (hw_params, &min, &dir)) < 0)

    goto min_rate_err;

  if ((err = snd_pcm_hw_params_get_rate_max (hw_params, &max, &dir)) < 0)

    goto max_rate_err;

  min_rate = min;

  max_rate = max;

  if (min_rate < 4000)

    min_rate = 4000;            /* random 'sensible minimum' */

  if (max_rate <= 0)

    max_rate = G_MAXINT;        /* or maybe just use 192400 or so? */

  else if (max_rate > 0 && max_rate < 4000)

    max_rate = MAX (4000, min_rate);

  GST_DEBUG_OBJECT (obj, "Min. rate = %u (%d)", min_rate, min);

  GST_DEBUG_OBJECT (obj, "Max. rate = %u (%d)", max_rate, max);

  caps = gst_caps_make_writable (in_caps);

  for (i = 0; i < gst_caps_get_size (caps); ++i) {

    GstStructure *s;

    s = gst_caps_get_structure (caps, i);

    if (min_rate == max_rate) {

      gst_structure_set (s, "rate", G_TYPE_INT, min_rate, NULL);

    } else {

      gst_structure_set (s, "rate", GST_TYPE_INT_RANGE,

          min_rate, max_rate, NULL);

    }

  }

  return caps;

  /* ERRORS */

min_rate_err:

  {

    GST_ERROR_OBJECT (obj, "failed to query minimum sample rate: %s",

        snd_strerror (err));

    gst_caps_unref (in_caps);

    return NULL;

  }

max_rate_err:

  {

    GST_ERROR_OBJECT (obj, "failed to query maximum sample rate: %s",

        snd_strerror (err));

    gst_caps_unref (in_caps);

    return NULL;

  }

}

static const struct

{

  const int width;

  const int depth;

  const int sformat;

  const int uformat;

} pcmformats[] = {

  {

  8, 8, SND_PCM_FORMAT_S8, SND_PCM_FORMAT_U8}, {

  16, 16, SND_PCM_FORMAT_S16, SND_PCM_FORMAT_U16}, {

  32, 24, SND_PCM_FORMAT_S24, SND_PCM_FORMAT_U24}, {

#if (G_BYTE_ORDER == G_LITTLE_ENDIAN)   /* no endian-unspecific enum available */

  24, 24, SND_PCM_FORMAT_S24_3LE, SND_PCM_FORMAT_U24_3LE}, {

#else

  24, 24, SND_PCM_FORMAT_S24_3BE, SND_PCM_FORMAT_U24_3BE}, {

#endif

  32, 32, SND_PCM_FORMAT_S32, SND_PCM_FORMAT_U32}

};

static GstCaps *

gst_alsa_detect_formats (GstObject * obj, snd_pcm_hw_params_t * hw_params,

    GstCaps * in_caps)

{

  snd_pcm_format_mask_t *mask;

  GstStructure *s;

  GstCaps *caps;

  gint i;

  snd_pcm_format_mask_malloc (&mask);

  snd_pcm_hw_params_get_format_mask (hw_params, mask);

  caps = gst_caps_new_empty ();

  for (i = 0; i < gst_caps_get_size (in_caps); ++i) {

    GstStructure *scopy;

    gint w, width = 0, depth = 0;

    s = gst_caps_get_structure (in_caps, i);

    if (!gst_structure_has_name (s, "audio/x-raw-int")) {

      GST_WARNING_OBJECT (obj, "skipping non-int format");

      continue;

    }

    if (!gst_structure_get_int (s, "width", &width) ||

        !gst_structure_get_int (s, "depth", &depth))

      continue;

    if (width == 0 || (width % 8) != 0)

      continue;                 /* Only full byte widths are valid */

    for (w = 0; w < G_N_ELEMENTS (pcmformats); w++)

      if (pcmformats[w].width == width && pcmformats[w].depth == depth)

        break;

    if (w == G_N_ELEMENTS (pcmformats))

      continue;                 /* Unknown format */

    if (snd_pcm_format_mask_test (mask, pcmformats[w].sformat) &&

        snd_pcm_format_mask_test (mask, pcmformats[w].uformat)) {

      /* template contains { true, false } or just one, leave it as it is */

      scopy = gst_structure_copy (s);

    } else if (snd_pcm_format_mask_test (mask, pcmformats[w].sformat)) {

      scopy = gst_structure_copy (s);

      gst_structure_set (scopy, "signed", G_TYPE_BOOLEAN, TRUE, NULL);

    } else if (snd_pcm_format_mask_test (mask, pcmformats[w].uformat)) {

      scopy = gst_structure_copy (s);

      gst_structure_set (scopy, "signed", G_TYPE_BOOLEAN, FALSE, NULL);

    } else {

      scopy = NULL;

    }

    if (scopy) {

      if (width > 8) {

        /* TODO: proper endianness detection, for now it's CPU endianness only */

        gst_structure_set (scopy, "endianness", G_TYPE_INT, G_BYTE_ORDER, NULL);

      }

      gst_caps_append_structure (caps, scopy);

    }

  }

  snd_pcm_format_mask_free (mask);

  gst_caps_unref (in_caps);

  return caps;

}

/* we don't have channel mappings for more than this many channels */

#define GST_ALSA_MAX_CHANNELS 8

static GstStructure *

get_channel_free_structure (const GstStructure * in_structure)

{

  GstStructure *s = gst_structure_copy (in_structure);

  gst_structure_remove_field (s, "channels");

  return s;

}

static void

caps_add_channel_configuration (GstCaps * caps,

    const GstStructure * in_structure, gint min_chans, gint max_chans)

{

  GstAudioChannelPosition pos[8] = {

    GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,

    GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,

    GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,

    GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT,

    GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,

    GST_AUDIO_CHANNEL_POSITION_LFE,

    GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,

    GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT

  };

  GstStructure *s = NULL;

  gint c;

  if (min_chans == max_chans && max_chans <= 2) {

    s = get_channel_free_structure (in_structure);

    gst_structure_set (s, "channels", G_TYPE_INT, max_chans, NULL);

    gst_caps_append_structure (caps, s);

    return;

  }

  g_assert (min_chans >= 1);

  /* mono and stereo don't need channel configurations */

  if (min_chans == 2) {

    s = get_channel_free_structure (in_structure);

    gst_structure_set (s, "channels", G_TYPE_INT, 2, NULL);

    gst_caps_append_structure (caps, s);

  } else if (min_chans == 1 && max_chans >= 2) {

    s = get_channel_free_structure (in_structure);

    gst_structure_set (s, "channels", GST_TYPE_INT_RANGE, 1, 2, NULL);

    gst_caps_append_structure (caps, s);

  }

  /* don't know whether to use 2.1 or 3.0 here - but I suspect

   * alsa might work around that/fix it somehow. Can we tell alsa

   * what our channel layout is like? */

  if (max_chans >= 3 && min_chans <= 3) {

    GstAudioChannelPosition pos_21[3] = {

      GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,

      GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,

      GST_AUDIO_CHANNEL_POSITION_LFE

    };

    s = get_channel_free_structure (in_structure);

    gst_structure_set (s, "channels", G_TYPE_INT, 3, NULL);

    gst_audio_set_channel_positions (s, pos_21);

    gst_caps_append_structure (caps, s);

  }

  /* everything else (4, 6, 8 channels) needs a channel layout */

  for (c = MAX (4, min_chans); c <= 8; c += 2) {

    if (max_chans >= c) {

      s = get_channel_free_structure (in_structure);

      gst_structure_set (s, "channels", G_TYPE_INT, c, NULL);

      gst_audio_set_channel_positions (s, pos);

      gst_caps_append_structure (caps, s);

    }

  }

  for (c = MAX (9, min_chans); c <= max_chans; ++c) {

    GstAudioChannelPosition *ch_layout;

    guint i;

    ch_layout = g_new (GstAudioChannelPosition, c);

    for (i = 0; i < c; ++i) {

      ch_layout[i] = GST_AUDIO_CHANNEL_POSITION_NONE;

    }

    s = get_channel_free_structure (in_structure);

    gst_structure_set (s, "channels", G_TYPE_INT, c, NULL);

    gst_audio_set_channel_positions (s, ch_layout);

    gst_caps_append_structure (caps, s);

    g_free (ch_layout);

  }

}

static GstCaps *

gst_alsa_detect_channels (GstObject * obj, snd_pcm_hw_params_t * hw_params,

    GstCaps * in_caps)

{

  GstCaps *caps;

  guint min, max;

  gint min_chans, max_chans;

  gint err, i;

  GST_LOG_OBJECT (obj, "probing channels ...");

  if ((err = snd_pcm_hw_params_get_channels_min (hw_params, &min)) < 0)

    goto min_chan_error;

  if ((err = snd_pcm_hw_params_get_channels_max (hw_params, &max)) < 0)

    goto max_chan_error;

  /* note: the above functions may return (guint) -1 */

  min_chans = min;

  max_chans = max;

  if (min_chans < 0) {

    min_chans = 1;

    max_chans = GST_ALSA_MAX_CHANNELS;

  } else if (max_chans < 0) {

    max_chans = GST_ALSA_MAX_CHANNELS;

  }

  if (min_chans > max_chans) {

    gint temp;

    GST_WARNING_OBJECT (obj, "minimum channels > maximum channels (%d > %d), "

        "please fix your soundcard drivers", min, max);

    temp = min_chans;

    min_chans = max_chans;

    max_chans = temp;

  }

  /* pro cards seem to return large numbers for min_channels */

  if (min_chans > GST_ALSA_MAX_CHANNELS) {

    GST_DEBUG_OBJECT (obj, "min_chans = %u, looks like a pro card", min_chans);

    if (max_chans < min_chans) {

      max_chans = min_chans;

    } else {

      /* only support [max_chans; max_chans] for these cards for now

       * to avoid inflating the source caps with loads of structures ... */

      min_chans = max_chans;

    }

  } else {

    min_chans = MAX (min_chans, 1);

    max_chans = MIN (GST_ALSA_MAX_CHANNELS, max_chans);

  }

  GST_DEBUG_OBJECT (obj, "Min. channels = %d (%d)", min_chans, min);

  GST_DEBUG_OBJECT (obj, "Max. channels = %d (%d)", max_chans, max);

  caps = gst_caps_new_empty ();

  for (i = 0; i < gst_caps_get_size (in_caps); ++i) {

    GstStructure *s;

    GType field_type;

    gint c_min = min_chans;

    gint c_max = max_chans;

    s = gst_caps_get_structure (in_caps, i);

    /* the template caps might limit the number of channels (like alsasrc),

     * in which case we don't want to return a superset, so hack around this

     * for the two common cases where the channels are either a fixed number

     * or a min/max range). Example: alsasrc template has channels = [1,2] and 

     * the detection will claim to support 8 channels for device 'plughw:0' */

    field_type = gst_structure_get_field_type (s, "channels");

    if (field_type == G_TYPE_INT) {

      gst_structure_get_int (s, "channels", &c_min);

      gst_structure_get_int (s, "channels", &c_max);

    } else if (field_type == GST_TYPE_INT_RANGE) {

      const GValue *val;

      val = gst_structure_get_value (s, "channels");

      c_min = CLAMP (gst_value_get_int_range_min (val), min_chans, max_chans);

      c_max = CLAMP (gst_value_get_int_range_max (val), min_chans, max_chans);

    } else {

      c_min = min_chans;

      c_max = max_chans;

    }

    caps_add_channel_configuration (caps, s, c_min, c_max);

  }

  gst_caps_unref (in_caps);

  return caps;

  /* ERRORS */

min_chan_error:

  {

    GST_ERROR_OBJECT (obj, "failed to query minimum channel count: %s",

        snd_strerror (err));

    return NULL;

  }

max_chan_error:

  {

    GST_ERROR_OBJECT (obj, "failed to query maximum channel count: %s",

        snd_strerror (err));

    return NULL;

  }

}

snd_pcm_t *

gst_alsa_open_iec958_pcm (GstObject * obj)

{

  char *iec958_pcm_name = NULL;

  snd_pcm_t *pcm = NULL;

  int res;

  char devstr[256];             /* Storage for local 'default' device string */

  /*

   * Try and open our default iec958 device. Fall back to searching on card x

   * if this fails, which should only happen on older alsa setups

   */

  /* The string will be one of these:

   * SPDIF_CON: Non-audio flag not set:

   *    spdif:{AES0 0x0 AES1 0x82 AES2 0x0 AES3 0x2}

   * SPDIF_CON: Non-audio flag set:

   *    spdif:{AES0 0x2 AES1 0x82 AES2 0x0 AES3 0x2}

   */

  sprintf (devstr,

      "iec958:{AES0 0x%02x AES1 0x%02x AES2 0x%02x AES3 0x%02x}",

      IEC958_AES0_CON_EMPHASIS_NONE | IEC958_AES0_NONAUDIO,

      IEC958_AES1_CON_ORIGINAL | IEC958_AES1_CON_PCM_CODER,

      0, IEC958_AES3_CON_FS_48000);

  GST_DEBUG_OBJECT (obj, "Generated device string \"%s\"", devstr);

  iec958_pcm_name = devstr;

  res = snd_pcm_open (&pcm, iec958_pcm_name, SND_PCM_STREAM_PLAYBACK, 0);

  if (G_UNLIKELY (res < 0)) {

    GST_DEBUG_OBJECT (obj, "failed opening IEC958 device: %s",

        snd_strerror (res));

    pcm = NULL;

  }

  return pcm;

}

/*

 * gst_alsa_probe_supported_formats:

 *

 * Takes the template caps and returns the subset which is actually

 * supported by this device.

 *

 */

GstCaps *

gst_alsa_probe_supported_formats (GstObject * obj, snd_pcm_t * handle,

    const GstCaps * template_caps)

{

  snd_pcm_hw_params_t *hw_params;

  snd_pcm_stream_t stream_type;

  GstCaps *caps;

  gint err;

  snd_pcm_hw_params_malloc (&hw_params);

  if ((err = snd_pcm_hw_params_any (handle, hw_params)) < 0)

    goto error;

  stream_type = snd_pcm_stream (handle);

  caps = gst_caps_copy (template_caps);

  if (!(caps = gst_alsa_detect_formats (obj, hw_params, caps)))

    goto subroutine_error;

  if (!(caps = gst_alsa_detect_rates (obj, hw_params, caps)))

    goto subroutine_error;

  if (!(caps = gst_alsa_detect_channels (obj, hw_params, caps)))

    goto subroutine_error;

  /* Try opening IEC958 device to see if we can support that format (playback

   * only for now but we could add SPDIF capture later) */

  if (stream_type == SND_PCM_STREAM_PLAYBACK) {

    snd_pcm_t *pcm = gst_alsa_open_iec958_pcm (obj);

    if (G_LIKELY (pcm)) {

      gst_caps_append (caps, gst_caps_new_simple ("audio/x-iec958", NULL));

      snd_pcm_close (pcm);

    }

  }

  snd_pcm_hw_params_free (hw_params);

  return caps;

  /* ERRORS */

error:

  {

    GST_ERROR_OBJECT (obj, "failed to query formats: %s", snd_strerror (err));

    snd_pcm_hw_params_free (hw_params);

    return NULL;

  }

subroutine_error:

  {

    GST_ERROR_OBJECT (obj, "failed to query formats");

    snd_pcm_hw_params_free (hw_params);

    return NULL;

  }

}

static gchar *

gst_alsa_find_device_name_no_handle (GstObject * obj, const gchar * devcard,

    gint device_num, snd_pcm_stream_t stream)

{

  snd_ctl_card_info_t *info = NULL;

  snd_ctl_t *ctl = NULL;

  gchar *ret = NULL;

  gint dev = -1;

  GST_LOG_OBJECT (obj, "[%s] device=%d", devcard, device_num);

  if (snd_ctl_open (&ctl, devcard, 0) < 0)

    return NULL;

  snd_ctl_card_info_malloc (&info);

  if (snd_ctl_card_info (ctl, info) < 0)

    goto done;

  while (snd_ctl_pcm_next_device (ctl, &dev) == 0 && dev >= 0) {

    if (dev == device_num) {

      snd_pcm_info_t *pcminfo;

      snd_pcm_info_malloc (&pcminfo);

      snd_pcm_info_set_device (pcminfo, dev);

      snd_pcm_info_set_subdevice (pcminfo, 0);

      snd_pcm_info_set_stream (pcminfo, stream);

      if (snd_ctl_pcm_info (ctl, pcminfo) < 0) {

        snd_pcm_info_free (pcminfo);

        break;

      }

      ret = g_strdup (snd_pcm_info_get_name (pcminfo));

      snd_pcm_info_free (pcminfo);

      GST_LOG_OBJECT (obj, "name from pcminfo: %s", GST_STR_NULL (ret));

    }

  }

  if (ret == NULL) {

    char *name = NULL;

    gint card;

    GST_LOG_OBJECT (obj, "no luck so far, trying backup");

    card = snd_ctl_card_info_get_card (info);

    snd_card_get_name (card, &name);

    ret = g_strdup (name);

    free (name);

  }

done:

  snd_ctl_card_info_free (info);

  snd_ctl_close (ctl);

  return ret;

}

gchar *

gst_alsa_find_device_name (GstObject * obj, const gchar * device,

    snd_pcm_t * handle, snd_pcm_stream_t stream)

{

  gchar *ret = NULL;

  if (device != NULL) {

    gchar *dev, *comma;

    gint devnum;