/* GStreamer

 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>

 *                    2000 Wim Taymans <wtay@chello.be>

 *

 * gstpadtemplate.c: Templates for pad creation

 *

 * 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.

 */

/**

 * SECTION:gstpadtemplate

 * @title: GstPadTemplate

 * @short_description: Describe the media type of a pad.

 * @see_also: #GstPad, #GstElementFactory

 *

 * Padtemplates describe the possible media types a pad or an elementfactory can

 * handle. This allows for both inspection of handled types before loading the

 * element plugin as well as identifying pads on elements that are not yet

 * created (request or sometimes pads).

 *

 * Pad and PadTemplates have #GstCaps attached to it to describe the media type

 * they are capable of dealing with. gst_pad_template_get_caps() or

 * GST_PAD_TEMPLATE_CAPS() are used to get the caps of a padtemplate. It's not

 * possible to modify the caps of a padtemplate after creation.

 *

 * PadTemplates have a #GstPadPresence property which identifies the lifetime

 * of the pad and that can be retrieved with GST_PAD_TEMPLATE_PRESENCE(). Also

 * the direction of the pad can be retrieved from the #GstPadTemplate with

 * GST_PAD_TEMPLATE_DIRECTION().

 *

 * The GST_PAD_TEMPLATE_NAME_TEMPLATE () is important for GST_PAD_REQUEST pads

 * because it has to be used as the name in the gst_element_get_request_pad()

 * call to instantiate a pad from this template.

 *

 * Padtemplates can be created with gst_pad_template_new() or with

 * gst_static_pad_template_get (), which creates a #GstPadTemplate from a

 * #GstStaticPadTemplate that can be filled with the

 * convenient GST_STATIC_PAD_TEMPLATE() macro.

 *

 * A padtemplate can be used to create a pad (see gst_pad_new_from_template()

 * or gst_pad_new_from_static_template ()) or to add to an element class

 * (see gst_element_class_add_static_pad_template ()).

 *

 * The following code example shows the code to create a pad from a padtemplate.

 * |[

 *   GstStaticPadTemplate my_template =

 *   GST_STATIC_PAD_TEMPLATE (

 *     "sink",          // the name of the pad

 *     GST_PAD_SINK,    // the direction of the pad

 *     GST_PAD_ALWAYS,  // when this pad will be present

 *     GST_STATIC_CAPS (        // the capabilities of the padtemplate

 *       "audio/x-raw, "

 *         "channels = (int) [ 1, 6 ]"

 *     )

 *   );

 *   void

 *   my_method (void)

 *   {

 *     GstPad *pad;

 *     pad = gst_pad_new_from_static_template (&my_template, "sink");

 *     ...

 *   }

 * ]|

 *

 * The following example shows you how to add the padtemplate to an

 * element class, this is usually done in the class_init of the class:

 * |[

 *   static void

 *   my_element_class_init (GstMyElementClass *klass)

 *   {

 *     GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

 *

 *     gst_element_class_add_static_pad_template (gstelement_class, &my_template);

 *   }

 * ]|

 */

#include "gst_private.h"

#include "gstpad.h"

#include "gstpadtemplate.h"

#include "gstenumtypes.h"

#include "gstutils.h"

#include "gstinfo.h"

#include "gsterror.h"

#include "gstvalue.h"

#define GST_CAT_DEFAULT GST_CAT_PADS

enum

{

  PROP_NAME_TEMPLATE = 1,

  PROP_DIRECTION,

  PROP_PRESENCE,

  PROP_CAPS,

  PROP_GTYPE,

};

enum

{

  TEMPL_PAD_CREATED,

  /* FILL ME */

  LAST_SIGNAL

};

static guint gst_pad_template_signals[LAST_SIGNAL] = { 0 };

static void gst_pad_template_dispose (GObject * object);

static void gst_pad_template_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec);

static void gst_pad_template_get_property (GObject * object, guint prop_id,

    GValue * value, GParamSpec * pspec);

#define gst_pad_template_parent_class parent_class

G_DEFINE_TYPE (GstPadTemplate, gst_pad_template, GST_TYPE_OBJECT);

static void

gst_pad_template_class_init (GstPadTemplateClass * klass)

{

  GObjectClass *gobject_class;

  GstObjectClass *gstobject_class;

  gobject_class = (GObjectClass *) klass;

  gstobject_class = (GstObjectClass *) klass;

  /**

   * GstPadTemplate::pad-created:

   * @pad_template: the object which received the signal.

   * @pad: the pad that was created.

   *

   * This signal is fired when an element creates a pad from this template.

   */

  gst_pad_template_signals[TEMPL_PAD_CREATED] =

      g_signal_new ("pad-created", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,

      G_STRUCT_OFFSET (GstPadTemplateClass, pad_created),

      NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_PAD);

  gobject_class->dispose = gst_pad_template_dispose;

  gobject_class->get_property = gst_pad_template_get_property;

  gobject_class->set_property = gst_pad_template_set_property;

  /**

   * GstPadTemplate:name-template:

   *

   * The name template of the pad template.

   */

  g_object_class_install_property (gobject_class, PROP_NAME_TEMPLATE,

      g_param_spec_string ("name-template", "Name template",

          "The name template of the pad template", NULL,

          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

  /**

   * GstPadTemplate:direction:

   *

   * The direction of the pad described by the pad template.

   */

  g_object_class_install_property (gobject_class, PROP_DIRECTION,

      g_param_spec_enum ("direction", "Direction",

          "The direction of the pad described by the pad template",

          GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,

          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

  /**

   * GstPadTemplate:presence:

   *

   * When the pad described by the pad template will become available.

   */

  g_object_class_install_property (gobject_class, PROP_PRESENCE,

      g_param_spec_enum ("presence", "Presence",

          "When the pad described by the pad template will become available",

          GST_TYPE_PAD_PRESENCE, GST_PAD_ALWAYS,

          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

  /**

   * GstPadTemplate:caps:

   *

   * The capabilities of the pad described by the pad template.

   */

  g_object_class_install_property (gobject_class, PROP_CAPS,

      g_param_spec_boxed ("caps", "Caps",

          "The capabilities of the pad described by the pad template",

          GST_TYPE_CAPS,

          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

  /**

   * GstPadTemplate:gtype:

   *

   * The type of the pad described by the pad template.

   *

   * Since: 1.14

   */

  g_object_class_install_property (gobject_class, PROP_GTYPE,

      g_param_spec_gtype ("gtype", "GType",

          "The GType of the pad described by the pad template",

          G_TYPE_NONE,

          G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));

  gstobject_class->path_string_separator = "*";

}

static void

gst_pad_template_init (GstPadTemplate * templ)

{

  /* GstPadTemplate objects are usually leaked */

  GST_OBJECT_FLAG_SET (templ, GST_OBJECT_FLAG_MAY_BE_LEAKED);

  GST_PAD_TEMPLATE_GTYPE (templ) = G_TYPE_NONE;

}

static void

gst_pad_template_dispose (GObject * object)

{

  GstPadTemplate *templ = GST_PAD_TEMPLATE (object);

  g_free (GST_PAD_TEMPLATE_NAME_TEMPLATE (templ));

  if (GST_PAD_TEMPLATE_CAPS (templ)) {

    gst_caps_unref (GST_PAD_TEMPLATE_CAPS (templ));

  }

  G_OBJECT_CLASS (parent_class)->dispose (object);

}

/* ALWAYS padtemplates cannot have conversion specifications (like src_%d),

 * since it doesn't make sense.

 * SOMETIMES padtemplates can do whatever they want, they are provided by the

 * element.

 * REQUEST padtemplates can have multiple specifiers in case of %d and %u, like

 * src_%u_%u, but %s only can be used once in the template.

 */

static gboolean

name_is_valid (const gchar * name, GstPadPresence presence)

{

  const gchar *str, *underscore = NULL;

  gboolean has_s = FALSE;

  if (presence == GST_PAD_ALWAYS) {

    if (strchr (name, '%')) {

      g_warning ("invalid name template %s: conversion specifications are not"

          " allowed for GST_PAD_ALWAYS padtemplates", name);

      return FALSE;

    }

  } else if (presence == GST_PAD_REQUEST) {

    str = strchr (name, '%');

    while (str) {

      if (*(str + 1) != 's' && *(str + 1) != 'd' && *(str + 1) != 'u') {

        g_warning

            ("invalid name template %s: conversion specification must be of"

            " type '%%d', '%%u' or '%%s' for GST_PAD_REQUEST padtemplate",

            name);

        return FALSE;

      }

      if (*(str + 1) == 's' && (*(str + 2) != '\0' || has_s)) {

        g_warning

            ("invalid name template %s: conversion specification of type '%%s'"

            "only can be used once in the GST_PAD_REQUEST padtemplate at the "

            "very end and not allowed any other characters with '%%s'", name);

        return FALSE;

      }

      if (*(str + 1) == 's') {

        has_s = TRUE;

      }

      underscore = strchr (str, '_');

      str = strchr (str + 1, '%');

      if (str && (!underscore || (underscore && str < underscore))) {

        g_warning

            ("invalid name template %s: each of conversion specifications "

            "must be separated by an underscore", name);

        return FALSE;

      }

    }

  }

  return TRUE;

}

G_DEFINE_POINTER_TYPE (GstStaticPadTemplate, gst_static_pad_template);

/**

 * gst_static_pad_template_get:

 * @pad_template: the static pad template

 *

 * Converts a #GstStaticPadTemplate into a #GstPadTemplate.

 *

 * Returns: (transfer floating) (nullable): a new #GstPadTemplate.

 */

/* FIXME0.11: rename to gst_pad_template_new_from_static_pad_template() */

GstPadTemplate *

gst_static_pad_template_get (GstStaticPadTemplate * pad_template)

{

  GstPadTemplate *new;

  GstCaps *caps;

  if (!name_is_valid (pad_template->name_template, pad_template->presence))

    return NULL;

  caps = gst_static_caps_get (&pad_template->static_caps);

  new = g_object_new (gst_pad_template_get_type (),

      "name", pad_template->name_template,

      "name-template", pad_template->name_template,

      "direction", pad_template->direction,

      "presence", pad_template->presence, "caps", caps, NULL);

  gst_caps_unref (caps);

  return new;

}

/**

 * gst_pad_template_new_from_static_pad_template_with_gtype:

 * @pad_template: the static pad template

 * @pad_type: The #GType of the pad to create

 *

 * Converts a #GstStaticPadTemplate into a #GstPadTemplate with a type.

 *

 * Returns: (transfer floating): a new #GstPadTemplate.

 *

 * Since: 1.14

 */

GstPadTemplate *

gst_pad_template_new_from_static_pad_template_with_gtype (GstStaticPadTemplate *

    pad_template, GType pad_type)

{

  GstPadTemplate *new;

  GstCaps *caps;

  g_return_val_if_fail (g_type_is_a (pad_type, GST_TYPE_PAD), NULL);

  if (!name_is_valid (pad_template->name_template, pad_template->presence))

    return NULL;

  caps = gst_static_caps_get (&pad_template->static_caps);

  new = g_object_new (gst_pad_template_get_type (),

      "name", pad_template->name_template,

      "name-template", pad_template->name_template,

      "direction", pad_template->direction,

      "presence", pad_template->presence, "caps", caps, "gtype", pad_type,

      NULL);

  gst_caps_unref (caps);

  return new;

}

/**

 * gst_pad_template_new:

 * @name_template: the name template.

 * @direction: the #GstPadDirection of the template.

 * @presence: the #GstPadPresence of the pad.

 * @caps: (transfer none): a #GstCaps set for the template.

 *

 * Creates a new pad template with a name according to the given template

 * and with the given arguments.

 *

 * Returns: (transfer floating) (nullable): a new #GstPadTemplate.

 */

GstPadTemplate *

gst_pad_template_new (const gchar * name_template,

    GstPadDirection direction, GstPadPresence presence, GstCaps * caps)

{

  GstPadTemplate *new;

  g_return_val_if_fail (name_template != NULL, NULL);

  g_return_val_if_fail (caps != NULL, NULL);

  g_return_val_if_fail (direction == GST_PAD_SRC

      || direction == GST_PAD_SINK, NULL);

  g_return_val_if_fail (presence == GST_PAD_ALWAYS

      || presence == GST_PAD_SOMETIMES || presence == GST_PAD_REQUEST, NULL);

  if (!name_is_valid (name_template, presence)) {

    return NULL;

  }

  new = g_object_new (gst_pad_template_get_type (),

      "name", name_template, "name-template", name_template,

      "direction", direction, "presence", presence, "caps", caps, NULL);

  return new;

}

/**

 * gst_pad_template_new_with_gtype:

 * @name_template: the name template.

 * @direction: the #GstPadDirection of the template.

 * @presence: the #GstPadPresence of the pad.

 * @caps: (transfer none): a #GstCaps set for the template.

 * @pad_type: The #GType of the pad to create

 *

 * Creates a new pad template with a name according to the given template

 * and with the given arguments.

 *

 * Returns: (transfer floating): a new #GstPadTemplate.

 *

 * Since: 1.14

 */

GstPadTemplate *

gst_pad_template_new_with_gtype (const gchar * name_template,

    GstPadDirection direction, GstPadPresence presence, GstCaps * caps,

    GType pad_type)

{

  GstPadTemplate *new;

  g_return_val_if_fail (name_template != NULL, NULL);

  g_return_val_if_fail (caps != NULL, NULL);

  g_return_val_if_fail (direction == GST_PAD_SRC

      || direction == GST_PAD_SINK, NULL);

  g_return_val_if_fail (presence == GST_PAD_ALWAYS

      || presence == GST_PAD_SOMETIMES || presence == GST_PAD_REQUEST, NULL);

  g_return_val_if_fail (g_type_is_a (pad_type, GST_TYPE_PAD), NULL);

  if (!name_is_valid (name_template, presence)) {

    return NULL;

  }

  new = g_object_new (gst_pad_template_get_type (),

      "name", name_template, "name-template", name_template,

      "direction", direction, "presence", presence, "caps", caps,

      "gtype", pad_type, NULL);

  return new;

}

/**

 * gst_static_pad_template_get_caps:

 * @templ: a #GstStaticPadTemplate to get capabilities of.

 *

 * Gets the capabilities of the static pad template.

 *

 * Returns: (transfer full): the #GstCaps of the static pad template.

 * Unref after usage. Since the core holds an additional

 * ref to the returned caps, use gst_caps_make_writable()

 * on the returned caps to modify it.

 */

GstCaps *

gst_static_pad_template_get_caps (GstStaticPadTemplate * templ)

{

  g_return_val_if_fail (templ, NULL);

  return gst_static_caps_get (&templ->static_caps);

}

/**

 * gst_pad_template_get_caps:

 * @templ: a #GstPadTemplate to get capabilities of.

 *

 * Gets the capabilities of the pad template.

 *

 * Returns: (transfer full): the #GstCaps of the pad template.

 * Unref after usage.

 */

GstCaps *

gst_pad_template_get_caps (GstPadTemplate * templ)

{

  GstCaps *caps;

  g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);

  caps = GST_PAD_TEMPLATE_CAPS (templ);

  return (caps ? gst_caps_ref (caps) : NULL);

}

/**

 * gst_pad_template_pad_created:

 * @templ: a #GstPadTemplate that has been created

 * @pad:   the #GstPad that created it

 *

 * Emit the pad-created signal for this template when created by this pad.

 */

void

gst_pad_template_pad_created (GstPadTemplate * templ, GstPad * pad)

{

  g_signal_emit (templ, gst_pad_template_signals[TEMPL_PAD_CREATED], 0, pad);

}

static void

gst_pad_template_set_property (GObject * object, guint prop_id,

    const GValue * value, GParamSpec * pspec)

{

  /* these properties are all construct-only */

  switch (prop_id) {

    case PROP_NAME_TEMPLATE:

      GST_PAD_TEMPLATE_NAME_TEMPLATE (object) = g_value_dup_string (value);

      break;

    case PROP_DIRECTION:

      GST_PAD_TEMPLATE_DIRECTION (object) =

          (GstPadDirection) g_value_get_enum (value);

      break;

    case PROP_PRESENCE:

      GST_PAD_TEMPLATE_PRESENCE (object) =

          (GstPadPresence) g_value_get_enum (value);

      break;

    case PROP_CAPS:

      GST_PAD_TEMPLATE_CAPS (object) = g_value_dup_boxed (value);

      if (GST_PAD_TEMPLATE_CAPS (object) != NULL) {

        /* GstPadTemplate are usually leaked so are their caps */

        GST_MINI_OBJECT_FLAG_SET (GST_PAD_TEMPLATE_CAPS (object),

            GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);

      }

      break;

    case PROP_GTYPE:

      GST_PAD_TEMPLATE_GTYPE (object) = g_value_get_gtype (value);

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}

static void

gst_pad_template_get_property (GObject * object, guint prop_id, GValue * value,

    GParamSpec * pspec)

{

  /* these properties are all construct-only */

  switch (prop_id) {

    case PROP_NAME_TEMPLATE:

      g_value_set_string (value, GST_PAD_TEMPLATE_NAME_TEMPLATE (object));

      break;

    case PROP_DIRECTION:

      g_value_set_enum (value, GST_PAD_TEMPLATE_DIRECTION (object));

      break;

    case PROP_PRESENCE:

      g_value_set_enum (value, GST_PAD_TEMPLATE_PRESENCE (object));

      break;

    case PROP_CAPS:

      g_value_set_boxed (value, GST_PAD_TEMPLATE_CAPS (object));

      break;

    case PROP_GTYPE:

      g_value_set_gtype (value, GST_PAD_TEMPLATE_GTYPE (object));

      break;

    default:

      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);

      break;

  }

}