/* concat muxer plugin for GStreamer
 * Copyright (C) 2004 Renato Filhps <renato.filho@indt.org.br>
 *
 * 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-concatmux
 * @short_description: Concat that takes one or several digital streams
 * and muxes them to a single stream.
 *
 * <refsect2>
 * <title>Sample pipelines</title>
 * <para>
 * Here is a simple pipeline to concat 2 files into a another file:
 * <programlisting>
 * gst-launch concatmux name=m ! filesink location=output.txt  filesrc location=file_a.txt !  m. filesrc location=file_b.txt ! m.
 * </programlisting>
 * </para>
 * </refsect2>
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <gst/gst.h>
#include <gst/base/gstcollectpads.h>

#include <string.h>

GST_DEBUG_CATEGORY_STATIC (gst_concat_mux_debug);
#define GST_CAT_DEFAULT gst_concat_mux_debug

#define GST_TYPE_CONCAT_MUX (gst_concat_mux_get_type())
#define GST_CONCAT_MUX(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_CONCAT_MUX, GstConcatMux))
#define GST_CONCAT_MUX_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_CONCAT_MUX, GstConcatMux))
#define GST_IS_CONCAT_MUX(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_CONCAT_MUX))
#define GST_IS_CONCAT_MUX_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_CONCAT_MUX))

typedef struct _GstConcatMux GstConcatMux;
typedef struct _GstConcatMuxClass GstConcatMuxClass;

/**
 * GstConcatMux:
 *
 * The opaque #GstConcatMux structure.
 */
struct _GstConcatMux
{
  GstElement element;

  /* Caps */
  GstCaps *sink_caps;

  /* pad */
  GstPad *srcpad;
  GstPad *sinkpad;

  /* sinkpads */
  GSList *sinks;
  gint numpads;

  /* offset in stream */
  guint64 offset;
  guint64 timeoffset;
  guint64 start_time;

  gboolean negotiated;
  gboolean resync;
  gboolean done;
};

struct _GstConcatMuxClass
{
  GstElementClass parent_class;
};

/* elementfactory information */
static const GstElementDetails gst_concat_mux_details =
GST_ELEMENT_DETAILS ("Concat muxer",
    "Codec/Muxer",
    "mux concat streams",
    "Renato Filho <renato.filho@indt.org>");

static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS_ANY
    );

static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink_%d",
    GST_PAD_SINK,
    GST_PAD_REQUEST,
    GST_STATIC_CAPS_ANY         
    );

static void gst_concat_mux_base_init (gpointer g_class);
static void gst_concat_mux_class_init (GstConcatMuxClass * klass);
static void gst_concat_mux_init (GstConcatMux * concat_mux);

static void gst_concat_mux_finalize (GObject * object);

static gboolean gst_concat_mux_handle_src_event (GstPad * pad,
    GstEvent * event);
static gboolean gst_concat_mux_handle_sink_event (GstPad * pad,
    GstEvent * event);

static GstPad *gst_concat_mux_request_new_pad (GstElement * element,
    GstPadTemplate * templ, const gchar * name);
static GstStateChangeReturn gst_concat_mux_change_state (GstElement *
    element, GstStateChange transition);

static GstFlowReturn gst_concat_mux_chain (GstPad * pad,  GstBuffer * buf);
static void gst_concat_mux_clear (GstConcatMux *mux);


static GstElementClass *parent_class = NULL;

GType
gst_concat_mux_get_type (void)
{
  static GType concat_mux_type = 0;

  if (!concat_mux_type) {
    static const GTypeInfo concat_mux_info = {
      sizeof (GstConcatMuxClass),
      gst_concat_mux_base_init,
      NULL,
      (GClassInitFunc) gst_concat_mux_class_init,
      NULL,
      NULL,
      sizeof (GstConcatMux),
      0,
      (GInstanceInitFunc) gst_concat_mux_init,
    };

    concat_mux_type =
        g_type_register_static (GST_TYPE_ELEMENT, "GstConcatMux",
        &concat_mux_info, 0);
  }
  return concat_mux_type;
}

static void
gst_concat_mux_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&src_factory));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&sink_factory));

  gst_element_class_set_details (element_class, &gst_concat_mux_details);
}

static void
gst_concat_mux_class_init (GstConcatMuxClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_peek_parent (klass);

  gobject_class->finalize = gst_concat_mux_finalize;

  gstelement_class->request_new_pad = gst_concat_mux_request_new_pad;
  gstelement_class->change_state = gst_concat_mux_change_state;
}

static void
gst_concat_mux_init (GstConcatMux * concat_mux)
{
  GstElementClass *klass = GST_ELEMENT_GET_CLASS (concat_mux);

  concat_mux->srcpad =
      gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
          "src"), "src");
  gst_pad_set_event_function (concat_mux->srcpad,
      gst_concat_mux_handle_src_event);
  gst_element_add_pad (GST_ELEMENT (concat_mux), concat_mux->srcpad);
}

static void
gst_concat_mux_finalize (GObject * object)
{
  GstConcatMux *concat_mux;

  concat_mux = GST_CONCAT_MUX (object);
  gst_concat_mux_clear (GST_CONCAT_MUX (object));

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gst_concat_mux_free_pad (gpointer data,
                            gpointer user_data)
{
   GMutex *mux;

   mux = gst_pad_get_element_private (GST_PAD (data));
   g_mutex_unlock (mux);
   g_mutex_free (mux);
   gst_object_unref (GST_OBJECT (data)); 
}

static void
gst_concat_mux_clear (GstConcatMux *mux)
{
  mux->resync = TRUE;
  mux->timeoffset = 0;
  mux->offset = 0;
  mux->negotiated = FALSE;
  mux->done = TRUE;
  if (mux->sinks != NULL) {
    g_slist_foreach (mux->sinks, gst_concat_mux_free_pad, mux);
    g_slist_free (mux->sinks);
    mux->sinks = NULL;
  }
}


static GstPadLinkReturn
gst_concat_mux_sinkconnect (GstPad * pad, GstPad * peer)
{
  gchar *pad_name = NULL;
  GstConcatMux *concat_mux;

  concat_mux = GST_CONCAT_MUX (gst_pad_get_parent (pad));

  if (concat_mux->sink_caps != NULL) {
      GstCaps *peer_caps = gst_pad_get_caps (peer);
      GstCaps *intersect;

      intersect =  gst_caps_intersect (concat_mux->sink_caps, peer_caps);
      if (intersect == NULL) {
          gst_caps_unref (peer_caps);
          return GST_PAD_LINK_NOFORMAT;
      }
      gst_caps_unref (peer_caps);
      gst_caps_unref (intersect);
  } else {
      concat_mux->sink_caps = gst_pad_get_caps (pad);
  }

  pad_name = gst_pad_get_name (pad);

  GST_DEBUG_OBJECT (concat_mux, "sinkconnect triggered on %s", pad_name);

  g_free (pad_name);

  gst_object_unref (concat_mux);

  return GST_PAD_LINK_OK;
}

static GstPad *
gst_concat_mux_request_new_pad (GstElement * element,
    GstPadTemplate * templ, const gchar * req_name)
{
  GstConcatMux *concat_mux;
  GstPad *newpad;
  GstElementClass *klass = GST_ELEMENT_GET_CLASS (element);
  GMutex *mutex;

  g_return_val_if_fail (templ != NULL, NULL);

  if (templ->direction != GST_PAD_SINK) {
    g_warning ("concat_mux: request pad that is not a SINK pad\n");
    return NULL;
  }

  g_return_val_if_fail (GST_IS_CONCAT_MUX (element), NULL);

  concat_mux = GST_CONCAT_MUX (element);

  if (templ == gst_element_class_get_pad_template (klass, "sink_%d")) {
    gchar *name;

    /* create new pad with the name */
    name = g_strdup_printf ("sink_%02d", concat_mux->numpads);
    g_debug ("NEw pad %s", name);
    newpad = gst_pad_new_from_template (templ, name);
    g_free (name);
    concat_mux->sinks = g_slist_append (concat_mux->sinks, newpad);
    g_debug ("New sink %p / %d", newpad, g_slist_length (concat_mux->sinks));
    concat_mux->numpads++;
  } else {
    g_warning ("concat_mux: this is not our template!\n");
    return NULL;
  }

  mutex = g_mutex_new ();

  if (concat_mux->sinkpad == NULL) {
      concat_mux->sinkpad = newpad;
  }
  else {
      g_mutex_lock (mutex);
  }

  gst_pad_set_element_private (newpad, mutex);
  /* setup some pad functions */
  gst_pad_set_link_function (newpad, gst_concat_mux_sinkconnect);
  gst_pad_set_event_function (newpad, gst_concat_mux_handle_sink_event);
  gst_pad_set_chain_function (newpad, gst_concat_mux_chain);

  /* add the pad to the element */
  gst_element_add_pad (element, newpad);

  return newpad;
}

/* handle events */
static gboolean
gst_concat_mux_handle_src_event (GstPad * pad, GstEvent * event)
{
  GstConcatMux *concat_mux;
  GstEventType type;

  concat_mux = GST_CONCAT_MUX (gst_pad_get_parent (pad));

  type = event ? GST_EVENT_TYPE (event) : GST_EVENT_UNKNOWN;

  switch (type) {
    case GST_EVENT_SEEK:
      /* disable seeking for now */
      return FALSE;
    default:
      break;
  }

  gst_object_unref (concat_mux);

  return gst_pad_event_default (pad, event);
}

/* handle events */
static gboolean
gst_concat_mux_handle_sink_event (GstPad * pad, GstEvent * event)
{
  GstConcatMux *mux;
  GstEventType type;

  mux = GST_CONCAT_MUX (gst_pad_get_parent (pad));

  type = event ? GST_EVENT_TYPE (event) : GST_EVENT_UNKNOWN;

  switch (type) {
    case GST_EVENT_EOS:
    {
        mux->resync = TRUE;
        g_debug ("sink EOS %p / %d", pad, g_slist_length (mux->sinks));
        /* mark pad eos */
        mux->sinks  = g_slist_remove (mux->sinks, pad);
        g_debug ("sink len %d", g_slist_length (mux->sinks));
        if (g_slist_length (mux->sinks) != 0) {
           GMutex *mutex;
           mux->sinkpad = mux->sinks->data;
           mutex = (GMutex *) gst_pad_get_element_private (mux->sinkpad);
           g_mutex_unlock (mutex);
           g_debug ("sink pad %p", mux->sinkpad);
           return TRUE;
        }

        g_debug ("sink list is empty");
    }
    default:
      break;
  }

  gst_object_unref (mux);

  return gst_pad_event_default (pad, event);
}

static GstFlowReturn
gst_concat_mux_chain (GstPad * pad,  GstBuffer * buf)
{
  GstConcatMux *mux = (GstConcatMux *) GST_PAD_PARENT (pad);
  GstBuffer *databuf = NULL;
  GstFlowReturn ret = GST_FLOW_OK;
  GMutex *mutex;


  mutex = (GMutex*) gst_pad_get_element_private (pad);

  g_mutex_lock (mutex);
  if (mux->done) {
      g_debug ("DONE pad %p", pad);
      return GST_FLOW_OK;
  }

  databuf = gst_buffer_make_metadata_writable (buf);

  if (!mux->negotiated) {
      /*
    GstCaps *newcaps;
    newcaps = gst_pad_get_caps (mux->sinkpad);

    g_debug ("CAPS: %s",gst_caps_to_string (newcaps));

    if (!gst_pad_set_caps (mux->srcpad, newcaps))
      goto nego_error;
    */
    mux->negotiated = TRUE;            
  } 

  g_debug ("Running [%s]\n"
        "\tTOFFSET    [%"G_GUINT64_FORMAT"]\n"
        "\tB_TSTAMP   [%"G_GUINT64_FORMAT"]\n"
        "\tB_DURATION [%"G_GUINT64_FORMAT"]\n"
        "\tOFFSET     [%"G_GUINT64_FORMAT"]\n"
        "\tB_OFFSET   [%"G_GUINT64_FORMAT"]",
        gst_element_get_name (mux),
        mux->timeoffset, 
        GST_BUFFER_TIMESTAMP (databuf),
        GST_BUFFER_DURATION (databuf),
        mux->offset,
        GST_BUFFER_OFFSET (databuf));


  if (mux->resync) {
    g_debug ("RESYNC [%s]", gst_element_get_name (mux));
    mux->timeoffset += GST_BUFFER_TIMESTAMP (databuf);
    GST_BUFFER_TIMESTAMP (databuf) = mux->timeoffset;
    mux->timeoffset += GST_BUFFER_DURATION (databuf);

    mux->offset += GST_BUFFER_OFFSET (databuf);
    GST_BUFFER_OFFSET (databuf) = mux->offset;
    mux->offset += GST_BUFFER_SIZE (databuf);
    mux->resync = FALSE;
  } else {

    GST_BUFFER_TIMESTAMP (databuf) = mux->timeoffset;
    mux->timeoffset += GST_BUFFER_DURATION (databuf);

    GST_BUFFER_OFFSET (databuf) = mux->offset;
    mux->offset += GST_BUFFER_SIZE (databuf);
  }

  gst_buffer_set_caps (databuf, GST_PAD_CAPS (pad));
  ret = gst_pad_push (mux->srcpad, databuf);

  //gst_buffer_unref (buf);

  g_mutex_unlock (mutex);
  return ret;
/*
nego_error:
  {
    GST_WARNING_OBJECT (mux, "failed to set caps");
    GST_ELEMENT_ERROR (mux, CORE, NEGOTIATION, (NULL), (NULL));
    return GST_FLOW_NOT_NEGOTIATED;
  }
  */
  /*
no_caps:
  {
    GST_WARNING_OBJECT (mux, "no caps on the incoming buffer %p", best->buffer);
    GST_ELEMENT_ERROR (mux, CORE, NEGOTIATION, (NULL), (NULL));
    ret = GST_FLOW_NOT_NEGOTIATED;
    goto beach;
  }
  */
}

static GstStateChangeReturn
gst_concat_mux_change_state (GstElement * element, GstStateChange transition)
{
  GstConcatMux *concat_mux;
  GstStateChangeReturn ret;

  concat_mux = GST_CONCAT_MUX (element);

  switch (transition) {
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      concat_mux->done = FALSE;
      concat_mux->resync = TRUE;
      GST_DEBUG_OBJECT (concat_mux, "starting collect pads");
      break;
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      GST_DEBUG_OBJECT (concat_mux, "stopping collect pads");
      gst_concat_mux_clear (concat_mux);
      break;
    default:
      break;
  }

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
  if (ret == GST_STATE_CHANGE_FAILURE)
    return ret;

  switch (transition) {
    default:
      break;
  }

  return ret;
}

gboolean
gst_concat_mux_plugin_init (GstPlugin * plugin)
{
#ifdef ENABLE_NLS
  setlocale (LC_ALL, "");
  bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
#endif /* ENABLE_NLS */

  GST_DEBUG_CATEGORY_INIT (gst_concat_mux_debug, "concatmux", 0,
      "concat muxer");
      
  return gst_element_register (plugin, "concatmux", GST_RANK_NONE,
      GST_TYPE_CONCAT_MUX);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "concat muxer",
    "Concat streamers",
     plugin_init, VERSION, "LGPL", "ConcatMux", "")