/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.

*

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

* modify it under the terms of the GNU Lesser 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

* Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser 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.

*

* Description:

*

*/

//  Include Files  

#include "GstAudioRecordBin.h"

#include "gstfactorylists.h"

#include <gst/gst.h>

#include <string.h>

#include <stdlib.h>

GST_DEBUG_CATEGORY_STATIC (aud_recbin_cat);     // define category (statically)

#define GST_CAT_DEFAULT aud_recbin_cat     // set as default

/** Macro to enable weak ref monitoring, used to track

 * ref / unref problems. 

 * NOTE : DO NOT USE IN HARDWARE, can be used in EMULATOR ONLY */

//#define WEAK_REF

#ifdef WEAK_REF

#define MONITOR_REF(gobj) if( G_IS_OBJECT(gobj) ) g_object_weak_ref( G_OBJECT(gobj), sWeakNotify, (gpointer) #gobj)

/** Weak Ref callback */

static void sWeakNotify (gpointer  data, GObject  *where_the_object_was);

#else

#define MONITOR_REF(gobj) /* NOP */

#endif // WEAK_REF

/** Enable the caps filter */

//#define ENABLE_CAPS_FILTER

/** The struct used to indicated the filter criteria for gst plugin factory */

typedef struct

{

    /** The type of the factory */

    GstFactoryListType type;

    /** The caps expected to be supported by a sink pad */

    GstCaps* sinkCaps;

    /** The caps expected to be supported by a src pad */

    GstCaps* srcCaps;

} FilterData;

/** Create the capability filter */

static GstElement* sCreateCapsFilter( GstCaps* encCaps);

/** Creates the element , which accepts \a sinkcaps and 

 * provides \a srccaps on the src pad */

GstElement* sCreateCompatibleFilter(GstFactoryListType type,

        const gchar* name, GstCaps* sinkcaps, GstCaps* srccaps);

/** Utility function to create the caps depending on the mimetype, fills in the default

 * values

 * */

static GstCaps* sCreateCaps( const char* mimetype );

/**

 * Checks if a given element \a factory can accpet the \a caps on a pad

 * of given \a direction.

 */

gboolean gst_element_factory_can_accept_caps (GstElementFactory * factory,

    const GstCaps * caps, GstPadDirection direction )

{

  GList *templates;

  g_return_val_if_fail (factory != NULL, FALSE);

  g_return_val_if_fail (caps != NULL, FALSE);

  templates = factory->staticpadtemplates;

  while (templates) {

    GstStaticPadTemplate *template1 = (GstStaticPadTemplate *) templates->data;

    if (template1->direction == direction ) {

      if (gst_caps_is_subset( caps, gst_static_caps_get(&template1->static_caps)))

        return TRUE;

    }

    templates = g_list_next (templates);

  }

  return FALSE;

}

/**

 * Checks if the element factory has the \a klass_type and checks if the filter data

 * criteria ( accepts sinkCaps & srcCaps ) is met.

 */

static inline gboolean element_klass_filter (GstElementFactory * factory, const gchar *klass_type, FilterData* pData)

{

    const gchar *klass = NULL;

    gboolean sink_caps_supported = FALSE;

    gboolean src_caps_supported = FALSE;

    klass = gst_element_factory_get_klass (factory);

    GST_DEBUG("klass = %s\n", klass);

    if (strstr (klass, klass_type) != NULL)

    {

        sink_caps_supported = gst_element_factory_can_accept_caps( factory, pData->sinkCaps, GST_PAD_SINK );               

        src_caps_supported = gst_element_factory_can_accept_caps( factory, pData->srcCaps, GST_PAD_SRC );

        GST_INFO("%s fact name = %s, can sink %d can src %d \n",

                klass_type,

                GST_PLUGIN_FEATURE_NAME(factory),

                sink_caps_supported, src_caps_supported

                );

        return TRUE && sink_caps_supported && src_caps_supported;

    }

    return FALSE;

}

/**

 * gst_factory_list_is_type:

 * @factory: a #GstElementFactory

 * @type: a #GstFactoryListType

 *

 * Check if @factory if of the given types.

 *

 * Returns: %TRUE if @factory is of @type.

 */

gboolean gst_factory_list_is_type (GstElementFactory * factory, FilterData * pData)

{

    gboolean res = FALSE;

    const char* encoder_klass_str = "Encoder";

    const char* muxer_klass_str = "Muxer";

    /* NOTE : GST_FACTORY_LIST_SINK, GST_FACTORY_LIST_DECODER, GST_FACTORY_LIST_SRC

     * ignored.

     */

    if (!res && (pData->type & GST_FACTORY_LIST_ENCODER))

        res = element_klass_filter (factory,encoder_klass_str, pData);

    if (!res && (pData->type & GST_FACTORY_LIST_MUXER))

        res = element_klass_filter (factory,muxer_klass_str, pData);

    return res;

}

/** The element filter used along with gst registry feature filter;

 * The filter criteria is indicated in \a pData. */ 

static gboolean element_filter (GstPluginFeature * feature, FilterData * pData)

{

    gboolean res;

    /* we only care about element factories */

    if (G_UNLIKELY (!GST_IS_ELEMENT_FACTORY (feature)))

        return FALSE;

    res = gst_factory_list_is_type (GST_ELEMENT_FACTORY_CAST (feature), pData);

    return res;

}

/* function used to sort element features, by comparing the ranks.

 * If ranks are same, then the plugin name is used. */

static gint compare_ranks(GstPluginFeature * f1, GstPluginFeature * f2)

{

  gint diff;

  const gchar *rname1, *rname2;

  diff = gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1);

  if (diff != 0)

    return diff;

  rname1 = gst_plugin_feature_get_name (f1);

  rname2 = gst_plugin_feature_get_name (f2);

  diff = strcmp (rname2, rname1);

  return diff;

}

/** Returns a GList of factory elements, of a given \a type and which accpets \a sinkCaps and

 * and provides \a srcCaps.

 * */

GList* gst_factory_list_get_elements (GstFactoryListType type, GstCaps* sinkCaps, GstCaps* srcCaps)

{

    FilterData* pData = NULL;

    GList *list = NULL;

    // construct the data

    pData = (FilterData*) calloc(sizeof(FilterData), 1);

    pData->sinkCaps = sinkCaps;

    pData->srcCaps = srcCaps;

    pData->type = type;

    /* get the feature list using the filter */

    list = gst_default_registry_feature_filter ((GstPluginFeatureFilter)

            element_filter, FALSE, pData);

    free( pData );

    // sort depending on the ranks

    if ( list )

        list = g_list_sort( list, (GCompareFunc) compare_ranks );

    GST_INFO("sort list done");

    return list;

}

/** Gets the pad depending on th pad template. */

static GstPad * gst_element_get_pad_from_template (GstElement * element, GstPadTemplate * templ)

{

    GstPad *ret = NULL;

    GstPadPresence presence;

    /* If this function is ever exported, we need check the validity of `element'

     * and `templ', and to make sure the template actually belongs to the

     * element. */

    presence = GST_PAD_TEMPLATE_PRESENCE (templ);

    switch (presence) {

        case GST_PAD_ALWAYS:

        case GST_PAD_SOMETIMES:

            GST_INFO("presence : always/sometimes");

            ret = gst_element_get_static_pad (element, templ->name_template);

            if (!ret && presence == GST_PAD_ALWAYS)

                g_warning

                    ("Element %s has an ALWAYS template %s, but no pad of the same name",

                     GST_OBJECT_NAME (element), templ->name_template);

            break;

        case GST_PAD_REQUEST:

            GST_INFO("presence : request audio_1");

            //ret = gst_element_request_pad (element, templ, NULL);

            ret = gst_element_get_request_pad( element, "audio_%d");

            break;

    }

    return ret;

}

/* Finds compatible muxer sink pad, for a given \a encoder \ref GstElement */

static inline GstPad * get_compatible_muxer_sink_pad (GstElement * muxer, GstElement * encoder) //pass in the right arguments here

{

    GstPad *srcpad = 0, *sinkpad = 0;

    GstPadTemplate *srctempl = 0;

    GstPadTemplate *sinktempl = 0;

    srcpad = gst_element_get_static_pad (encoder, "src");

    srctempl = gst_pad_get_pad_template (srcpad);

    GST_DEBUG (

            "Attempting to find pad from muxer %s compatible with %s:%s",

            GST_ELEMENT_NAME (muxer), GST_DEBUG_PAD_NAME (srcpad));

    gst_object_unref( srcpad );

    sinktempl = gst_element_get_compatible_pad_template (muxer, srctempl);

    if (G_UNLIKELY (sinktempl == NULL))

        goto no_template;

    sinkpad = gst_element_get_pad_from_template (muxer, sinktempl);

    return sinkpad;

no_template:

    {

        GST_ERROR ("No compatible pad available on muxer");

        return NULL;

    }

}

/**

 * Creates the encoder bin.

 * If the function is successful, A encoder bin with a ghost sink pad 

 * which accepts the \a encCaps and a ghost source pad which gives

 * \a muxCaps type is available.

 * 

 * Algo:

 * 

 * 1. Check if any pads of src give out encCaps

 * 1.1 If yes, 

 *      -> Create a list of muxers available in the gst plugin repository and select the appropriate muxer

 *      -> connect src -> muxer, create encbin.

 * 1.2 If no,

 *      -> Create a list of encoders availabe in the gst plugin repo and  select a appropriate enc

 *      -> connect src -> capsfilter (optional) -> enc -> muxer and return encbin

 *      

 * 

 * \param [in] src The source gst element

 * \param [in] encCaps The capability of the encoder being created.

 * \param [in] muxCaps The capability type of the muxer to create.

 * 

 * \return On successful the ptr to encoder bin gst element is returned, else NULL.

 */

EXPORT_C GstElement* CreateAudioRecordBin( GstElement* src, GstCaps* encCaps, GstCaps* muxCaps)

{

    GstElement *encbin = NULL; // The top level encoder bin

    GstPad *ghostsrc = NULL, *ghostsink = NULL; // Ghost src, sink pads of the enc bin

    GstElement *muxer = NULL; // The muxer

    GstElement *encoder = NULL; // The encoder

#ifdef ENABLE_CAPS_FILTER

    GstElement * audiofilter = NULL; // Audio filter

#endif // ENABLE_CAPS_FILTER

    GstPad* src_pad = 0;

    gboolean accept_src_pad = 0;

    GstCaps* src_caps = 0;

    if ( !src || !encCaps || !muxCaps )

    {

    		GST_ERROR("invalid args");

    		return NULL;

    }    

    /* gst initialization */

    if ( FALSE == gst_init_check(NULL, NULL,NULL) )

    {

        GST_ERROR("gst_init_check FAIL");

        return NULL;

    }

    /* Initialize the debug category */

    GST_DEBUG_CATEGORY_INIT (aud_recbin_cat, "AudioRecordBin",

            0, "Audio record bin plugin");

    /* 1. Create the bin */

    encbin = gst_bin_new("encbin");

    if ( !encbin )

    {

        GST_ERROR("encbin creation FAIL");

        return NULL;

    }

    MONITOR_REF(encbin);

    /* 2. Get the src pad, of the source element */

    src_pad = gst_element_get_pad (src, "src");

    src_caps = gst_pad_get_caps( src_pad );

    /* 2.1 Check if the src gst element can directly give the encCaps */

    accept_src_pad = gst_caps_is_subset( encCaps ,src_caps);   

    GST_INFO(" accept caps %d ", accept_src_pad );

    gst_object_unref (src_pad);

    gst_caps_unref( src_caps );

    if ( !accept_src_pad )

    {

        GstCaps* enc_in_caps = 0;

        /* The src pad does not directly give the encoded format,

         * fallback to x-raw-int / x-raw-float and construct the pipeline

         * */

        enc_in_caps = sCreateCaps("audio/x-raw-int");

        encoder = sCreateCompatibleFilter( GST_FACTORY_LIST_ENCODER, "encoder", enc_in_caps, encCaps);

        if (!encoder )

        {

            GST_ERROR("encoder creation FAIL");

            gst_caps_unref( enc_in_caps );

            goto CLEANUP;

        }

#ifdef ENABLE_CAPS_FILTER

        audiofilter = sCreateCapsFilter(enc_in_caps);

#endif // ENABLE_CAPS_FILTER

        gst_caps_unref( enc_in_caps );

        // add elements to the enc bin

        if (gst_bin_add(GST_BIN(encbin), encoder))

        {

            GST_INFO("Added encoder to bin");

        }

        else

        {

            GST_ERROR("Could not add encoder to bin");

            goto CLEANUP;

        }

    }

    /* construct the muxer which can accept the encCaps and give out muxCaps */

#ifdef ENABLE_CAPS_FILTER

    /* Add a caps filter, if not created above */

    if ( !audiofilter )

        audiofilter = sCreateCapsFilter(encCaps);

    if ( !audiofilter)

    {

        GST_ERROR("audio filter creation FAIL ");

        goto CLEANUP;

    }

    MONITOR_REF(audiofilter);

    // add elements to the enc bin

    if (gst_bin_add(GST_BIN(encbin), audiofilter))

    {

        GST_INFO("Added audio filter to bin");

    }

    else

    {

        GST_ERROR("Could not add audio filter to bin");

        goto CLEANUP;

    }

#endif // ENABLE_CAPS_FILTER

    // Create the muxer 

    muxer = sCreateCompatibleFilter( GST_FACTORY_LIST_MUXER, "muxer", encCaps, muxCaps );

    if ( !muxer )

    {

        GST_ERROR("no suitable muxer found");

        goto CLEANUP;

    }

    MONITOR_REF(muxer);

    if (gst_bin_add(GST_BIN(encbin), muxer))

    {

        GST_INFO("Added muxer to bin");

    }

    else

    {

        GST_ERROR("Could not add muxer to bin");

        goto CLEANUP;

    }

    // link the added elements.

    // If encoder is present, then the bin will have,

    // capsfilter -> encoder -> muxer

    // or else

    // capsfilter -> muxer.

    // Note that caps filter is optionally controlled by macro ENABLE_CAPS_FILTER

    if ( encoder )

    {

        GstPad* srcpad      = 0;

        GstPad* muxerpad    = 0;

#ifdef ENABLE_CAPS_FILTER

        GST_INFO("audiofilter -> encoder");

        if(!gst_element_link(audiofilter, encoder))

        {

            GST_ERROR("Could not link audiofilter -> encoder!!");

            goto CLEANUP;

        }

#endif //ENABLE_CAPS_FILTER

        // get the src pad

        srcpad = gst_element_get_static_pad (encoder, "src");

        // get the sink pad of muxer

        GST_INFO("get compatible mux sink pad ... ");

        muxerpad = get_compatible_muxer_sink_pad (muxer, encoder);

        // link 

        if (G_UNLIKELY (gst_pad_link (srcpad, muxerpad) != GST_PAD_LINK_OK))

        {

            GST_ERROR("gst_pad_link fail");

            goto CLEANUP;

        }

        gst_object_unref( srcpad );

        gst_object_unref( muxerpad );

        GST_INFO("gst_pad_link successful");

    }

#ifdef ENABLE_CAPS_FILTER

    else 

    {

        GST_INFO("audiofilter -> muxer ");

        if(!gst_element_link(audiofilter, muxer))

        {

            GST_ERROR("Could not link audiofilter to muxer!!");

            goto CLEANUP;

        }

    }

#endif //ENABLE_CAPS_FILTER

    GST_INFO("linking complete");

    // create the ghost pads

    // The ghost src pad is provided by the muxer

    ghostsrc = gst_element_get_static_pad(muxer, "src");

    // The ghost sink pad is determined by the availability

    // of audiofilter, encoder.

#ifdef ENABLE_CAPS_FILTER

    ghostsink = gst_element_get_static_pad(audiofilter, "sink");

#else

    if ( encoder )

        ghostsink = gst_element_get_static_pad(encoder, "sink");

    else

        ghostsink = gst_element_get_static_pad(muxer, "sink");

#endif //ENABLE_CAPS_FILTER

    MONITOR_REF( ghostsrc );

    MONITOR_REF( ghostsink );

    if(ghostsrc)

    {

        gst_element_add_pad(encbin, gst_ghost_pad_new("src",ghostsrc));

        gst_object_unref(GST_OBJECT(ghostsrc));

        GST_INFO("+ghost src");

    }

    if(ghostsink)

    {

        gst_element_add_pad(encbin, gst_ghost_pad_new("sink",ghostsink));

        gst_object_unref(GST_OBJECT(ghostsink));

        GST_INFO("+ghost sink");

    }

    return encbin;