/*****************************************************************************

 * meter.c : audio meter

 *****************************************************************************

 * Copyright (C) 2020 VLC authors and VideoLAN

 *

 * This program 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 2.1 of the License, or

 * (at your option) any later version.

 *

 * This program 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 program; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.

 *****************************************************************************/

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#include <assert.h>

#include <vlc_common.h>

#include <vlc_configuration.h>

#include <vlc_aout.h>

#include "aout_internal.h"

struct vlc_audio_meter_plugin

{

    char *name;

    config_chain_t *cfg;

    filter_t *filter;

    vlc_tick_t last_date;

    struct vlc_audio_meter_plugin_owner owner;

    struct vlc_list node;

};

void

(vlc_audio_meter_Init)(struct vlc_audio_meter *meter, vlc_object_t *obj)

{

    vlc_mutex_init(&meter->lock);

    meter->parent = obj;

    meter->fmt = NULL;

    vlc_list_init(&meter->plugins);

}

void

vlc_audio_meter_Destroy(struct vlc_audio_meter *meter)

{

    vlc_audio_meter_plugin *plugin;

    vlc_list_foreach(plugin, &meter->plugins, node)

        vlc_audio_meter_RemovePlugin(meter, plugin);

}

static void

vlc_audio_meter_OnLoudnessChanged(filter_t *filter,

                             const struct vlc_audio_loudness *loudness)

{

    vlc_audio_meter_plugin *plugin = filter->owner.sys;

    if (plugin->owner.cbs->on_loudness != NULL)

        plugin->owner.cbs->on_loudness(plugin->last_date, loudness, plugin->owner.sys);

}

static filter_t *

vlc_audio_meter_CreatePluginFilter(struct vlc_audio_meter *meter, vlc_audio_meter_plugin *plugin)

{

    static const struct filter_audio_callbacks audio_cbs = {

        .meter_loudness = { .on_changed = vlc_audio_meter_OnLoudnessChanged }

    };

    const filter_owner_t owner = {

        .audio = &audio_cbs,

        .sys = plugin,

    };

    return aout_filter_Create(meter->parent, &owner, "audio meter", plugin->name,

                              meter->fmt, meter->fmt, plugin->cfg, true);

}

vlc_audio_meter_plugin *

vlc_audio_meter_AddPlugin(struct vlc_audio_meter *meter, const char *chain,

                          const struct vlc_audio_meter_plugin_owner *owner)

{

    assert(owner != NULL && owner->cbs != NULL);

    vlc_audio_meter_plugin *plugin = malloc(sizeof(*plugin));

    if (plugin == NULL)

        return NULL;

    plugin->owner = *owner;

    plugin->last_date = VLC_TICK_INVALID;

    plugin->name = NULL;

    plugin->cfg = NULL;

    plugin->filter = NULL;

    free(config_ChainCreate(&plugin->name, &plugin->cfg, chain));

    if (plugin->name == NULL)

        goto error;

    vlc_mutex_lock(&meter->lock);

    if (meter->fmt != NULL)

    {

        plugin->filter = vlc_audio_meter_CreatePluginFilter(meter, plugin);

        if (plugin->filter == NULL)

        {

            vlc_mutex_unlock(&meter->lock);

            goto error;

        }

        assert(plugin->filter->ops->drain_audio == NULL); /* Not supported */

    }

    vlc_list_append(&plugin->node, &meter->plugins);

    vlc_mutex_unlock(&meter->lock);

    return plugin;

error:

    free(plugin->name);

    if (plugin->cfg != NULL)

        config_ChainDestroy(plugin->cfg);

    free(plugin);

    return NULL;

}

void

vlc_audio_meter_RemovePlugin(struct vlc_audio_meter *meter, vlc_audio_meter_plugin *plugin)

{

    vlc_mutex_lock(&meter->lock);

    if (plugin->filter != NULL)

    {

        vlc_filter_Delete(plugin->filter);

    }

    if (plugin->cfg != NULL)

        config_ChainDestroy(plugin->cfg);

    free(plugin->name);

    vlc_list_remove(&plugin->node);

    free(plugin);

    vlc_mutex_unlock(&meter->lock);

}

int

vlc_audio_meter_Reset(struct vlc_audio_meter *meter, const audio_sample_format_t *fmt)

{

    int ret = VLC_SUCCESS;

    vlc_mutex_lock(&meter->lock);

    meter->fmt = fmt;

    /* Reload every plugins using the new fmt */

    vlc_audio_meter_plugin *plugin;

    vlc_list_foreach(plugin, &meter->plugins, node)

    {

        if (plugin->filter != NULL)

        {

            vlc_filter_Delete(plugin->filter);

            plugin->filter = NULL;

        }

        plugin->last_date = VLC_TICK_INVALID;

        if (meter->fmt != NULL)

        {

            plugin->filter = vlc_audio_meter_CreatePluginFilter(meter, plugin);

            if (plugin->filter == NULL)

            {

                ret = VLC_EGENERIC;

                break;

            }

        }

    }

    vlc_mutex_unlock(&meter->lock);

    return ret;

}

void

vlc_audio_meter_Process(struct vlc_audio_meter *meter, block_t *block, vlc_tick_t date)

{

    vlc_mutex_lock(&meter->lock);

    vlc_audio_meter_plugin *plugin;

    vlc_list_foreach(plugin, &meter->plugins, node)

    {

        filter_t *filter = plugin->filter;

        if (filter != NULL)

        {

            plugin->last_date = date + block->i_length;

            block_t *same_block = filter->ops->filter_audio(filter, block);

            assert(same_block == block); (void) same_block;

        }

    }

    vlc_mutex_unlock(&meter->lock);

}

void

vlc_audio_meter_Flush(struct vlc_audio_meter *meter)

{

    vlc_mutex_lock(&meter->lock);

    vlc_audio_meter_plugin *plugin;

    vlc_list_foreach(plugin, &meter->plugins, node)

    {

        filter_t *filter = plugin->filter;

        if (filter != NULL)

            filter_Flush(filter);

    }

    vlc_mutex_unlock(&meter->lock);

}