/* Generic video mixer plugin

 *

 * GStreamer

 * Copyright (C) 2015 Matthew Waters <matthew@centricular.com>

 *

 * 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., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <gst/gst.h>

#include <gst/video/video.h>

#include "gstglbasemixer.h"

#define GST_CAT_DEFAULT gst_gl_base_mixer_debug

GST_DEBUG_CATEGORY (gst_gl_base_mixer_debug);

static void gst_gl_base_mixer_pad_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec);

static void gst_gl_base_mixer_pad_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec);

static void gst_gl_base_mixer_set_context (GstElement * element,

    GstContext * context);

static GstStateChangeReturn gst_gl_base_mixer_change_state (GstElement *

    element, GstStateChange transition);

struct _GstGLBaseMixerPrivate

{

  gboolean negotiated;

  GstGLContext *other_context;

};

#define gst_gl_base_mixer_parent_class parent_class

G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GstGLBaseMixer, gst_gl_base_mixer,

    GST_TYPE_VIDEO_AGGREGATOR);

G_DEFINE_TYPE (GstGLBaseMixerPad, gst_gl_base_mixer_pad,

    GST_TYPE_VIDEO_AGGREGATOR_PAD);

static void

gst_gl_base_mixer_pad_class_init (GstGLBaseMixerPadClass * klass)

{

  GObjectClass *gobject_class = (GObjectClass *) klass;

  GstVideoAggregatorPadClass *vaggpad_class =

      (GstVideoAggregatorPadClass *) klass;

  gobject_class->set_property = gst_gl_base_mixer_pad_set_property;

  gobject_class->get_property = gst_gl_base_mixer_pad_get_property;

  vaggpad_class->prepare_frame = NULL;

  vaggpad_class->clean_frame = NULL;

}

static void

gst_gl_base_mixer_pad_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec)

{

  switch (prop_id) {

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static void

gst_gl_base_mixer_pad_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec)

{

  switch (prop_id) {

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static gboolean

_find_local_gl_context (GstGLBaseMixer * mix)

{

  if (gst_gl_query_local_gl_context (GST_ELEMENT (mix), GST_PAD_SRC,

          &mix->context))

    return TRUE;

  if (gst_gl_query_local_gl_context (GST_ELEMENT (mix), GST_PAD_SINK,

          &mix->context))

    return TRUE;

  return FALSE;

}

static gboolean

_get_gl_context (GstGLBaseMixer * mix)

{

  GstGLBaseMixerClass *mix_class = GST_GL_BASE_MIXER_GET_CLASS (mix);

  GError *error = NULL;

  if (!gst_gl_ensure_element_data (mix, &mix->display,

          &mix->priv->other_context))

    return FALSE;

  gst_gl_display_filter_gl_api (mix->display, mix_class->supported_gl_api);

  _find_local_gl_context (mix);

  GST_OBJECT_LOCK (mix->display);

  if (!mix->context) {

    do {

      if (mix->context) {

        gst_object_unref (mix->context);

        mix->context = NULL;

      }

      /* just get a GL context.  we don't care */

      mix->context =

          gst_gl_display_get_gl_context_for_thread (mix->display, NULL);

      if (!mix->context) {

        if (!gst_gl_display_create_context (mix->display,

                mix->priv->other_context, &mix->context, &error)) {

          GST_OBJECT_UNLOCK (mix->display);

          goto context_error;

        }

      }

    } while (!gst_gl_display_add_context (mix->display, mix->context));

  }

  GST_OBJECT_UNLOCK (mix->display);

  {

    GstGLAPI current_gl_api = gst_gl_context_get_gl_api (mix->context);

    if ((current_gl_api & mix_class->supported_gl_api) == 0)

      goto unsupported_gl_api;

  }

  return TRUE;

unsupported_gl_api:

  {

    GstGLAPI gl_api = gst_gl_context_get_gl_api (mix->context);

    gchar *gl_api_str = gst_gl_api_to_string (gl_api);

    gchar *supported_gl_api_str =

        gst_gl_api_to_string (mix_class->supported_gl_api);

    GST_ELEMENT_ERROR (mix, RESOURCE, BUSY,

        ("GL API's not compatible context: %s supported: %s", gl_api_str,

            supported_gl_api_str), (NULL));

    g_free (supported_gl_api_str);

    g_free (gl_api_str);

    return FALSE;

  }

context_error:

  {

    GST_ELEMENT_ERROR (mix, RESOURCE, NOT_FOUND, ("%s", error->message),

        (NULL));

    g_clear_error (&error);

    return FALSE;

  }

}

static gboolean

gst_gl_base_mixer_propose_allocation (GstAggregator * agg,

    GstAggregatorPad * aggpad, GstQuery * decide_query, GstQuery * query)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (agg);

  if (!_get_gl_context (mix))

    return FALSE;

  return TRUE;

}

static gboolean

gst_gl_base_mixer_sink_query (GstAggregator * agg, GstAggregatorPad * bpad,

    GstQuery * query)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (agg);

  GST_TRACE ("QUERY %" GST_PTR_FORMAT, query);

  switch (GST_QUERY_TYPE (query)) {

    case GST_QUERY_CONTEXT:

    {

      if (gst_gl_handle_context_query ((GstElement *) mix, query,

              mix->display, mix->context, mix->priv->other_context))

        return TRUE;

      break;

    }

    default:

      break;

  }

  return GST_AGGREGATOR_CLASS (parent_class)->sink_query (agg, bpad, query);;

}

static void

gst_gl_base_mixer_pad_init (GstGLBaseMixerPad * mixerpad)

{

}

/* GLBaseMixer signals and args */

enum

{

  /* FILL ME */

  LAST_SIGNAL

};

enum

{

  PROP_0,

  PROP_CONTEXT

};

static gboolean gst_gl_base_mixer_src_query (GstAggregator * agg,

    GstQuery * query);

static gboolean

gst_gl_base_mixer_src_activate_mode (GstAggregator * aggregator,

    GstPadMode mode, gboolean active);

static gboolean gst_gl_base_mixer_stop (GstAggregator * agg);

static gboolean gst_gl_base_mixer_start (GstAggregator * agg);

static void gst_gl_base_mixer_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec);

static void gst_gl_base_mixer_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec);

static gboolean gst_gl_base_mixer_decide_allocation (GstAggregator * agg,

    GstQuery * query);

static void

gst_gl_base_mixer_class_init (GstGLBaseMixerClass * klass)

{

  GObjectClass *gobject_class;

  GstElementClass *element_class;

  GstAggregatorClass *agg_class = (GstAggregatorClass *) klass;

  GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "glmixer", 0, "opengl mixer");

  gobject_class = (GObjectClass *) klass;

  element_class = GST_ELEMENT_CLASS (klass);

  gobject_class->get_property = gst_gl_base_mixer_get_property;

  gobject_class->set_property = gst_gl_base_mixer_set_property;

  element_class->set_context =

      GST_DEBUG_FUNCPTR (gst_gl_base_mixer_set_context);

  element_class->change_state = gst_gl_base_mixer_change_state;

  agg_class->sink_query = gst_gl_base_mixer_sink_query;

  agg_class->src_query = gst_gl_base_mixer_src_query;

  agg_class->src_activate = gst_gl_base_mixer_src_activate_mode;

  agg_class->stop = gst_gl_base_mixer_stop;

  agg_class->start = gst_gl_base_mixer_start;

  agg_class->decide_allocation = gst_gl_base_mixer_decide_allocation;

  agg_class->propose_allocation = gst_gl_base_mixer_propose_allocation;

  g_object_class_install_property (gobject_class, PROP_CONTEXT,

      g_param_spec_object ("context",

          "OpenGL context",

          "Get OpenGL context",

          GST_TYPE_GL_CONTEXT, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  /* Register the pad class */

  g_type_class_ref (GST_TYPE_GL_BASE_MIXER_PAD);

  klass->supported_gl_api = GST_GL_API_ANY;

}

static void

gst_gl_base_mixer_init (GstGLBaseMixer * mix)

{

  mix->priv = gst_gl_base_mixer_get_instance_private (mix);

}

static void

gst_gl_base_mixer_set_context (GstElement * element, GstContext * context)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (element);

  GstGLBaseMixerClass *mix_class = GST_GL_BASE_MIXER_GET_CLASS (mix);

  gst_gl_handle_set_context (element, context, &mix->display,

      &mix->priv->other_context);

  if (mix->display)

    gst_gl_display_filter_gl_api (mix->display, mix_class->supported_gl_api);

  GST_ELEMENT_CLASS (parent_class)->set_context (element, context);

}

static gboolean

gst_gl_base_mixer_activate (GstGLBaseMixer * mix, gboolean active)

{

  GstGLBaseMixerClass *mix_class = GST_GL_BASE_MIXER_GET_CLASS (mix);

  gboolean result = TRUE;

  if (active) {

    if (!gst_gl_ensure_element_data (mix, &mix->display,

            &mix->priv->other_context))

      return FALSE;

    gst_gl_display_filter_gl_api (mix->display, mix_class->supported_gl_api);

  }

  return result;

}

static gboolean

gst_gl_base_mixer_src_activate_mode (GstAggregator * aggregator,

    GstPadMode mode, gboolean active)

{

  GstGLBaseMixer *mix;

  gboolean result = FALSE;

  mix = GST_GL_BASE_MIXER (aggregator);

  switch (mode) {

    case GST_PAD_MODE_PUSH:

    case GST_PAD_MODE_PULL:

      result = gst_gl_base_mixer_activate (mix, active);

      break;

    default:

      result = TRUE;

      break;

  }

  return result;

}

static gboolean

gst_gl_base_mixer_src_query (GstAggregator * agg, GstQuery * query)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (agg);

  switch (GST_QUERY_TYPE (query)) {

    case GST_QUERY_CONTEXT:

    {

      if (gst_gl_handle_context_query ((GstElement *) mix, query,

              mix->display, mix->context, mix->priv->other_context))

        return TRUE;

      break;

    }

    default:

      break;

  }

  return GST_AGGREGATOR_CLASS (parent_class)->src_query (agg, query);

}

static gboolean

gst_gl_base_mixer_decide_allocation (GstAggregator * agg, GstQuery * query)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (agg);

  if (!_get_gl_context (mix))

    return FALSE;

  return TRUE;

}

static void

gst_gl_base_mixer_get_property (GObject * object,

    guint prop_id, GValue * value, GParamSpec * pspec)

{

  GstGLBaseMixer *mixer = GST_GL_BASE_MIXER (object);

  switch (prop_id) {

    case PROP_CONTEXT:

      g_value_set_object (value, mixer->context);

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static void

gst_gl_base_mixer_set_property (GObject * object,

    guint prop_id, const GValue * value, GParamSpec * pspec)

{

  switch (prop_id) {

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static gboolean

gst_gl_base_mixer_start (GstAggregator * agg)

{

  return GST_AGGREGATOR_CLASS (parent_class)->start (agg);;

}

static gboolean

gst_gl_base_mixer_stop (GstAggregator * agg)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (agg);

  if (mix->context) {

    gst_object_unref (mix->context);

    mix->context = NULL;

  }

  return TRUE;

}

static GstStateChangeReturn

gst_gl_base_mixer_change_state (GstElement * element, GstStateChange transition)

{

  GstGLBaseMixer *mix = GST_GL_BASE_MIXER (element);

  GstGLBaseMixerClass *mix_class = GST_GL_BASE_MIXER_GET_CLASS (mix);

  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;

  GST_DEBUG_OBJECT (mix, "changing state: %s => %s",

      gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),

      gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));

  switch (transition) {

    case GST_STATE_CHANGE_NULL_TO_READY:

      if (!gst_gl_ensure_element_data (element, &mix->display,

              &mix->priv->other_context))

        return GST_STATE_CHANGE_FAILURE;

      gst_gl_display_filter_gl_api (mix->display, mix_class->supported_gl_api);

      break;

    default:

      break;

  }

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

  if (ret == GST_STATE_CHANGE_FAILURE)

    return ret;

  switch (transition) {

    case GST_STATE_CHANGE_READY_TO_NULL:

      if (mix->priv->other_context) {

        gst_object_unref (mix->priv->other_context);

        mix->priv->other_context = NULL;

      }

      if (mix->display) {

        gst_object_unref (mix->display);

        mix->display = NULL;

      }

      break;

    default:

      break;

  }

  return ret;

}