/* GStreamer

 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>

 *

 * 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., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

/**

 * SECTION:element-mulawenc

 *

 * This element encode mulaw audio. Mulaw coding is also known as G.711.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gst/gst.h>

#include "mulaw-encode.h"

#include "mulaw-conversion.h"

extern GstStaticPadTemplate mulaw_enc_src_factory;

extern GstStaticPadTemplate mulaw_enc_sink_factory;

/* Stereo signals and args */

enum

{

  /* FILL ME */

  LAST_SIGNAL

};

enum

{

  ARG_0

};

static void gst_mulawenc_class_init (GstMuLawEncClass * klass);

static void gst_mulawenc_base_init (GstMuLawEncClass * klass);

static void gst_mulawenc_init (GstMuLawEnc * mulawenc);

static GstFlowReturn gst_mulawenc_chain (GstPad * pad, GstBuffer * buffer);

static GstElementClass *parent_class = NULL;

/*static guint gst_stereo_signals[LAST_SIGNAL] = { 0 }; */

static GstCaps *

mulawenc_getcaps (GstPad * pad)

{

  GstMuLawEnc *mulawenc;

  GstPad *otherpad;

  GstCaps *othercaps, *result;

  const GstCaps *templ;

  gchar *name;

  gint i;

  mulawenc = GST_MULAWENC (GST_PAD_PARENT (pad));

  /* figure out the name of the caps we are going to return */

  if (pad == mulawenc->srcpad) {

    name = "audio/x-mulaw";

    otherpad = mulawenc->sinkpad;

  } else {

    name = "audio/x-raw-int";

    otherpad = mulawenc->srcpad;

  }

  /* get caps from the peer, this can return NULL when there is no peer */

  othercaps = gst_pad_peer_get_caps (otherpad);

  /* get the template caps to make sure we return something acceptable */

  templ = gst_pad_get_pad_template_caps (pad);

  if (othercaps) {

    /* there was a peer */

    othercaps = gst_caps_make_writable (othercaps);

    /* go through the caps and remove the fields we don't want */

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

      GstStructure *structure;

      structure = gst_caps_get_structure (othercaps, i);

      /* adjust the name */

      gst_structure_set_name (structure, name);

      if (pad == mulawenc->srcpad) {

        /* remove the fields we don't want */

        gst_structure_remove_fields (structure, "width", "depth", "endianness",

            "signed", NULL);

      } else {

        /* add fixed fields */

        gst_structure_set (structure, "width", G_TYPE_INT, 16,

            "depth", G_TYPE_INT, 16,

            "endianness", G_TYPE_INT, G_BYTE_ORDER,

            "signed", G_TYPE_BOOLEAN, TRUE, NULL);

      }

    }

    /* filter against the allowed caps of the pad to return our result */

    result = gst_caps_intersect (othercaps, templ);

    gst_caps_unref (othercaps);

  } else {

    /* there was no peer, return the template caps */

    result = gst_caps_copy (templ);

  }

  return result;

}

static gboolean

mulawenc_setcaps (GstPad * pad, GstCaps * caps)

{

  GstMuLawEnc *mulawenc;

  GstPad *otherpad;

  GstStructure *structure;

  GstCaps *base_caps;

  mulawenc = GST_MULAWENC (gst_pad_get_parent (pad));

  structure = gst_caps_get_structure (caps, 0);

  gst_structure_get_int (structure, "channels", &mulawenc->channels);

  gst_structure_get_int (structure, "rate", &mulawenc->rate);

  if (pad == mulawenc->sinkpad) {

    otherpad = mulawenc->srcpad;

  } else {

    otherpad = mulawenc->sinkpad;

  }

  base_caps = gst_caps_copy (gst_pad_get_pad_template_caps (otherpad));

  structure = gst_caps_get_structure (base_caps, 0);

  gst_structure_set (structure, "rate", G_TYPE_INT, mulawenc->rate, NULL);

  gst_structure_set (structure, "channels", G_TYPE_INT, mulawenc->channels,

      NULL);

  gst_pad_set_caps (otherpad, base_caps);

  gst_object_unref (mulawenc);

  gst_caps_unref (base_caps);

  return TRUE;

}

GType

gst_mulawenc_get_type (void)

{

  static GType mulawenc_type = 0;

  if (!mulawenc_type) {

    static const GTypeInfo mulawenc_info = {

      sizeof (GstMuLawEncClass),

      (GBaseInitFunc) gst_mulawenc_base_init,

      NULL,

      (GClassInitFunc) gst_mulawenc_class_init,

      NULL,

      NULL,

      sizeof (GstMuLawEnc),

      0,

      (GInstanceInitFunc) gst_mulawenc_init,

    };

    mulawenc_type =

        g_type_register_static (GST_TYPE_ELEMENT, "GstMuLawEnc", &mulawenc_info,

        0);

  }

  return mulawenc_type;

}

static void

gst_mulawenc_base_init (GstMuLawEncClass * klass)

{

  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  const GstElementDetails mulawenc_details =

      GST_ELEMENT_DETAILS ("Mu Law audio encoder",

      "Codec/Encoder/Audio",

      "Convert 16bit PCM to 8bit mu law",

      "Zaheer Abbas Merali <zaheerabbas at merali dot org>");

  gst_element_class_add_pad_template (element_class,

      gst_static_pad_template_get (&mulaw_enc_src_factory));

  gst_element_class_add_pad_template (element_class,

      gst_static_pad_template_get (&mulaw_enc_sink_factory));

  gst_element_class_set_details (element_class, &mulawenc_details);

}

static void

gst_mulawenc_class_init (GstMuLawEncClass * klass)

{

  parent_class = g_type_class_peek_parent (klass);

}

static void

gst_mulawenc_init (GstMuLawEnc * mulawenc)

{

  mulawenc->sinkpad =

      gst_pad_new_from_static_template (&mulaw_enc_sink_factory, "sink");

  gst_pad_set_setcaps_function (mulawenc->sinkpad, mulawenc_setcaps);

  gst_pad_set_getcaps_function (mulawenc->sinkpad, mulawenc_getcaps);

  gst_pad_set_chain_function (mulawenc->sinkpad, gst_mulawenc_chain);

  gst_element_add_pad (GST_ELEMENT (mulawenc), mulawenc->sinkpad);

  mulawenc->srcpad =

      gst_pad_new_from_static_template (&mulaw_enc_src_factory, "src");

  gst_pad_set_setcaps_function (mulawenc->srcpad, mulawenc_setcaps);

  gst_pad_set_getcaps_function (mulawenc->srcpad, mulawenc_getcaps);

  gst_pad_use_fixed_caps (mulawenc->srcpad);

  gst_element_add_pad (GST_ELEMENT (mulawenc), mulawenc->srcpad);

  /* init rest */

  mulawenc->channels = 0;

  mulawenc->rate = 0;

}

static GstFlowReturn

gst_mulawenc_chain (GstPad * pad, GstBuffer * buffer)

{

  GstMuLawEnc *mulawenc;

  gint16 *linear_data;

  guint linear_size;

  guint8 *mulaw_data;

  guint mulaw_size;

  GstBuffer *outbuf;

  GstFlowReturn ret;

  GstClockTime timestamp, duration;

  mulawenc = GST_MULAWENC (gst_pad_get_parent (pad));

  if (!mulawenc->rate || !mulawenc->channels)

    goto not_negotiated;

  linear_data = (gint16 *) GST_BUFFER_DATA (buffer);

  linear_size = GST_BUFFER_SIZE (buffer);

  mulaw_size = linear_size / 2;

  timestamp = GST_BUFFER_TIMESTAMP (buffer);

  duration = GST_BUFFER_DURATION (buffer);

  ret = gst_pad_alloc_buffer_and_set_caps (mulawenc->srcpad,

      GST_BUFFER_OFFSET_NONE, mulaw_size, GST_PAD_CAPS (mulawenc->srcpad),

      &outbuf);

  if (ret != GST_FLOW_OK)

    goto alloc_failed;

  if (duration == -1) {

    duration = gst_util_uint64_scale_int (mulaw_size,

        GST_SECOND, mulawenc->rate * mulawenc->channels);

  }

  if (GST_BUFFER_SIZE (outbuf) < mulaw_size) {

    /* pad-alloc can suggest a smaller size */

    gst_buffer_unref (outbuf);

    outbuf = gst_buffer_new_and_alloc (mulaw_size);

  }

  mulaw_data = (guint8 *) GST_BUFFER_DATA (outbuf);

  /* copy discont flag */

  if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))

    GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);

  GST_BUFFER_TIMESTAMP (outbuf) = timestamp;

  GST_BUFFER_DURATION (outbuf) = duration;

  gst_buffer_set_caps (outbuf, GST_PAD_CAPS (mulawenc->srcpad));

  mulaw_encode (linear_data, mulaw_data, mulaw_size);

  gst_buffer_unref (buffer);

  ret = gst_pad_push (mulawenc->srcpad, outbuf);

done:

  gst_object_unref (mulawenc);

  return ret;

not_negotiated:

  {

    GST_DEBUG_OBJECT (mulawenc, "no format negotiated");

    ret = GST_FLOW_NOT_NEGOTIATED;

    gst_buffer_unref (buffer);

    goto done;

  }

alloc_failed:

  {

    GST_DEBUG_OBJECT (mulawenc, "pad alloc failed");

    gst_buffer_unref (buffer);

    goto done;

  }

}