/**
 * \file mlt_producer.c
 * \brief abstraction for all producer services
 * \see mlt_producer_s
 *
 * Copyright (C) 2003-2022 Meltytech, LLC
 *
 * 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 2.1 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "mlt_producer.h"
#include "mlt_factory.h"
#include "mlt_frame.h"
#include "mlt_log.h"
#include "mlt_parser.h"
#include "mlt_profile.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>  // for stat()
#include <sys/types.h> // for stat()
#include <time.h>      // for strftime() and gtime()
#include <unistd.h>    // for stat()

/* Forward references. */

static int producer_get_frame(mlt_service self, mlt_frame_ptr frame, int index);
static void mlt_producer_property_changed(mlt_service owner, mlt_producer self, mlt_event_data);
static void mlt_producer_service_changed(mlt_service owner, mlt_producer self);

/* for debugging */
//#define _MLT_PRODUCER_CHECKS_ 1
#ifdef _MLT_PRODUCER_CHECKS_
static int producers_created = 0;
static int producers_destroyed = 0;
#endif

/** Initialize a producer service.
 *
 * \public \memberof mlt_producer_s
 * \param self the producer structure to initialize
 * \param child a pointer to the child object for the subclass
 * \return true if there was an error
 */

int mlt_producer_init(mlt_producer self, void *child)
{
    // Check that we haven't received NULL
    int error = self == NULL;

    // Continue if no error
    if (error == 0) {
#ifdef _MLT_PRODUCER_CHECKS_
        producers_created++;
#endif

        // Initialise the producer
        memset(self, 0, sizeof(struct mlt_producer_s));

        // Associate with the child
        self->child = child;

        // Initialise the service
        if (mlt_service_init(&self->parent, self) == 0) {
            // The parent is the service
            mlt_service parent = &self->parent;

            // Define the parent close
            parent->close = (mlt_destructor) mlt_producer_close;
            parent->close_object = self;

            // For convenience, we'll assume the close_object is self
            self->close_object = self;

            // Get the properties of the parent
            mlt_properties properties = MLT_SERVICE_PROPERTIES(parent);

            // Set the default properties
            mlt_properties_set(properties, "mlt_type", "mlt_producer");
            mlt_properties_set_position(properties, "_position", 0.0);
            mlt_properties_set_double(properties, "_frame", 0);
            mlt_properties_set_double(properties, "_speed", 1.0);
            mlt_properties_set_position(properties, "in", 0);
            char *e = getenv("MLT_DEFAULT_PRODUCER_LENGTH");
            int p = e ? atoi(e) : 15000;
            mlt_properties_set_position(properties, "out", MAX(0, p - 1));
            mlt_properties_set_position(properties, "length", p);
            mlt_properties_set(properties, "eof", "pause");
            mlt_properties_set(properties, "resource", "<producer>");

            // Override service get_frame
            parent->get_frame = producer_get_frame;

            mlt_events_listen(properties,
                              self,
                              "service-changed",
                              (mlt_listener) mlt_producer_service_changed);
            mlt_events_listen(properties,
                              self,
                              "property-changed",
                              (mlt_listener) mlt_producer_property_changed);
            mlt_events_register(properties, "producer-changed");
        }
    }

    return error;
}

/** Listener for property changes.
 *
 * If the in, out, or length properties changed, fire a "producer-changed" event.
 *
 * \private \memberof mlt_producer_s
 * \param owner a service (ignored)
 * \param self the producer
 * \param name the property that changed
 */

static void mlt_producer_property_changed(mlt_service owner,
                                          mlt_producer self,
                                          mlt_event_data event_data)
{
    const char *name = mlt_event_data_to_string(event_data);
    if (!name)
        return;
    if (!strcmp(name, "in") || !strcmp(name, "out") || !strcmp(name, "length"))
        mlt_events_fire(MLT_PRODUCER_PROPERTIES(mlt_producer_cut_parent(self)),
                        "producer-changed",
                        mlt_event_data_none());
}

/** Listener for service changes.
 *
 * Fires the "producer-changed" event.
 *
 * \private \memberof mlt_producer_s
 * \param owner a service (ignored)
 * \param self the producer
 */

static void mlt_producer_service_changed(mlt_service owner, mlt_producer self)
{
    mlt_events_fire(MLT_PRODUCER_PROPERTIES(mlt_producer_cut_parent(self)),
                    "producer-changed",
                    mlt_event_data_none());
}

/** Create and initialize a new producer.
 *
 * \public \memberof mlt_producer_s
 * \return the new producer
 */

mlt_producer mlt_producer_new(mlt_profile profile)
{
    mlt_producer self = malloc(sizeof(struct mlt_producer_s));
    if (self) {
        if (mlt_producer_init(self, NULL) == 0) {
            mlt_properties_set_data(MLT_PRODUCER_PROPERTIES(self),
                                    "_profile",
                                    profile,
                                    0,
                                    NULL,
                                    NULL);
            mlt_properties_set_double(MLT_PRODUCER_PROPERTIES(self),
                                      "aspect_ratio",
                                      mlt_profile_sar(profile));
        } else {
            free(self);
            return NULL;
        }
    }
    return self;
}

/** Determine if producer is a cut.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return true if \p self is a "cut" producer
 * \see mlt_producer_cut
 */

int mlt_producer_is_cut(mlt_producer self)
{
    return mlt_properties_get_int(MLT_PRODUCER_PROPERTIES(self), "_cut");
}

/** Determine if producer is a mix.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return true if \p self is a "mix" producer
 * \todo Define a mix producer.
 */

int mlt_producer_is_mix(mlt_producer self)
{
    mlt_properties properties = self != NULL ? MLT_PRODUCER_PROPERTIES(self) : NULL;
    mlt_tractor tractor = properties != NULL ? mlt_properties_get_data(properties, "mlt_mix", NULL)
                                             : NULL;
    return tractor != NULL;
}

/** Determine if the producer is a blank.
 *
 * Blank producers should only appear as an item in a playlist.
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return true if \p self is a "blank" producer
 * \see mlt_playlist_insert_blank
 */

int mlt_producer_is_blank(mlt_producer self)
{
    if (self) {
        const char *resource = mlt_properties_get(MLT_PRODUCER_PROPERTIES(
                                                      mlt_producer_cut_parent(self)),
                                                  "resource");
        return (resource && !strcmp("blank", resource));
    }
    return (self == NULL);
}

/** Obtain the parent producer.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return either the parent producer if \p self is a "cut" producer or \p self otherwise.
 */

mlt_producer mlt_producer_cut_parent(mlt_producer self)
{
    mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);
    if (mlt_producer_is_cut(self))
        return mlt_properties_get_data(properties, "_cut_parent", NULL);
    else
        return self;
}

/** Create a cut of this producer.
 *
 * A "cut" is a portion of another (parent) producer.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param in the beginning
 * \param out the end
 * \return the new producer
 * \todo Expand on the value of a cut.
 */

mlt_producer mlt_producer_cut(mlt_producer self, int in, int out)
{
    mlt_producer result = mlt_producer_new(mlt_service_profile(MLT_PRODUCER_SERVICE(self)));
    mlt_producer parent = mlt_producer_cut_parent(self);
    mlt_properties properties = MLT_PRODUCER_PROPERTIES(result);
    mlt_properties parent_props = MLT_PRODUCER_PROPERTIES(parent);

    mlt_properties_set_lcnumeric(properties,
                                 mlt_properties_get_lcnumeric(MLT_PRODUCER_PROPERTIES(self)));

    mlt_events_block(MLT_PRODUCER_PROPERTIES(result), MLT_PRODUCER_PROPERTIES(result));
    // Special case - allow for a cut of the entire producer (this will squeeze all other cuts to 0)
    if (in <= 0)
        in = 0;
    if ((out < 0 || out >= mlt_producer_get_length(parent)) && !mlt_producer_is_blank(self))
        out = MAX(0, mlt_producer_get_length(parent) - 1);

    mlt_properties_inc_ref(parent_props);
    mlt_properties_set_int(properties, "_cut", 1);
    mlt_properties_set_data(properties,
                            "_cut_parent",
                            parent,
                            0,
                            (mlt_destructor) mlt_producer_close,
                            NULL);
    mlt_properties_set_position(properties,
                                "length",
                                mlt_properties_get_position(parent_props, "length"));
    mlt_properties_set_double(properties,
                              "aspect_ratio",
                              mlt_properties_get_double(parent_props, "aspect_ratio"));
    mlt_producer_set_in_and_out(result, in, out);

    return result;
}

/** Get the parent service object.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the service parent class
 * \see MLT_PRODUCER_SERVICE
 */

mlt_service mlt_producer_service(mlt_producer self)
{
    return self != NULL ? &self->parent : NULL;
}

/** Get the producer properties.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the producer's property list
 * \see MLT_PRODUCER_PROPERTIES
 */

mlt_properties mlt_producer_properties(mlt_producer self)
{
    return MLT_SERVICE_PROPERTIES(&self->parent);
}

/** Seek to a specified position.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param position set the "play head" position of the producer
 * \return false
 * \todo Document how the properties affect behavior.
 * \see mlt_producer_seek_time
 */

int mlt_producer_seek(mlt_producer self, mlt_position position)
{
    if (self->seek) {
        return self->seek(self, position);
    }

    // Determine eof handling
    mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);
    char *eof = mlt_properties_get(properties, "eof");
    int use_points = 1 - mlt_properties_get_int(properties, "ignore_points");

    // Recursive behaviour for cuts - repositions parent and then repositions cut
    // hence no return on this condition
    if (mlt_producer_is_cut(self))
        mlt_producer_seek(mlt_producer_cut_parent(self), position + mlt_producer_get_in(self));

    // Check bounds
    if (mlt_service_identify(MLT_PRODUCER_SERVICE(self)) == mlt_service_link_type) {
        // Do not bounds check a link.
    } else if (position < 0 || mlt_producer_get_playtime(self) == 0) {
        position = 0;
    } else if (use_points && (eof == NULL || !strcmp(eof, "pause"))
               && position >= mlt_producer_get_playtime(self)) {
        mlt_producer_set_speed(self, 0);
        position = mlt_producer_get_playtime(self) - 1;
    } else if (use_points && eof && !strcmp(eof, "loop")
               && position >= mlt_producer_get_playtime(self)) {
        position = (int) position % (int) mlt_producer_get_playtime(self);
    }

    // Set the position
    mlt_properties_set_position(MLT_PRODUCER_PROPERTIES(self), "_position", position);

    // Calculate the absolute frame
    mlt_properties_set_position(MLT_PRODUCER_PROPERTIES(self),
                                "_frame",
                                use_points * mlt_producer_get_in(self) + position);

    return 0;
}

/** Seek to a specified time string.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param time set the "play head" position of the producer to the time string
 * \return false
 * \see mlt_producer_seek
 */

int mlt_producer_seek_time(mlt_producer self, const char *time)
{
    mlt_properties_set(MLT_PRODUCER_PROPERTIES(self), "_seek_time", time);
    mlt_position position = mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "_seek_time");
    return mlt_producer_seek(self, position);
}

/** Get the current position (relative to in point).
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the position of the "play head" relative to its beginning
 */

mlt_position mlt_producer_position(mlt_producer self)
{
    return mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "_position");
}

/** Get the current position (relative to start of producer).
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the position of the "play head" regardless of the in point
 */

mlt_position mlt_producer_frame(mlt_producer self)
{
    return mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "_frame");
}

/** Get the current position (relative to start of producer) as a time string.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param format the time value format
 * \return the position of the "play head" regardless of the in point
 */

char *mlt_producer_frame_time(mlt_producer self, mlt_time_format format)
{
    return mlt_properties_get_time(MLT_PRODUCER_PROPERTIES(self), "_frame", format);
}

/** Set the playing speed.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param speed the new speed as a relative factor (1.0 = normal)
 * \return true if error
 */

int mlt_producer_set_speed(mlt_producer self, double speed)
{
    return mlt_properties_set_double(MLT_PRODUCER_PROPERTIES(self), "_speed", speed);
}

/** Get the playing speed.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the speed as a relative factor (1.0 = normal)
 */

double mlt_producer_get_speed(mlt_producer self)
{
    return mlt_properties_get_double(MLT_PRODUCER_PROPERTIES(self), "_speed");
}

/** Get the frames per second.
 *
 * This is determined by the producer's profile.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the video refresh rate
 */

double mlt_producer_get_fps(mlt_producer self)
{
    mlt_profile profile = mlt_service_profile(MLT_PRODUCER_SERVICE(self));
    return mlt_profile_fps(profile);
}

/** Set the in and out points.
 *
 * The in point is where play out should start relative to the natural start
 * of the underlying file. The out point is where play out should end, also
 * relative to the start of the underlying file. If the underlying resource is
 * a live stream, then the in point is an offset relative to first usable
 * sample.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param in the relative starting time; a negative value is the same as 0
 * \param out the relative ending time; a negative value is the same as length - 1
 * \return false
 */

int mlt_producer_set_in_and_out(mlt_producer self, mlt_position in, mlt_position out)
{
    if (self->set_in_and_out) {
        return self->set_in_and_out(self, in, out);
    }

    mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);

    // Correct ins and outs if necessary
    if (in < 0)
        in = 0;
    else if (in >= mlt_producer_get_length(self))
        in = MAX(0, mlt_producer_get_length(self) - 1);

    if (mlt_producer_is_blank(self) && out >= mlt_producer_get_length(self))
        // Extend the blank producer if needed.
        mlt_properties_set_position(MLT_PRODUCER_PROPERTIES(self), "length", out + 1);
    else if (out < 0 || out >= mlt_producer_get_length(self))
        // Get the out point from the length.
        out = MAX(0, mlt_producer_get_length(self) - 1);

    // Swap ins and outs if wrong
    if (out < in) {
        mlt_position t = in;
        in = out;
        out = t;
    }

    // Set the values
    mlt_events_block(properties, properties);
    mlt_properties_set_position(properties, "in", in);
    mlt_events_unblock(properties, properties);
    mlt_properties_set_position(properties, "out", out);

    return 0;
}

/** Physically reduce the producer (typically a cut) to a 0 length.
 *  Essentially, all 0 length cuts should be immediately removed by containers.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return false
 */

int mlt_producer_clear(mlt_producer self)
{
    if (self != NULL) {
        mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);
        mlt_events_block(properties, properties);
        mlt_properties_set_position(properties, "in", 0);
        mlt_events_unblock(properties, properties);
        mlt_properties_set_position(properties, "out", -1);
    }
    return 0;
}

/** Get the in point.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the in point
 */

mlt_position mlt_producer_get_in(mlt_producer self)
{
    return mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "in");
}

/** Get the out point.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the out point
 */

mlt_position mlt_producer_get_out(mlt_producer self)
{
    return mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "out");
}

/** Get the total play time.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the playable (based on in and out points) duration
 */

mlt_position mlt_producer_get_playtime(mlt_producer self)
{
    return mlt_producer_get_out(self) - mlt_producer_get_in(self) + 1;
}

/** Get the total, unedited length of the producer.
 *
 * The value returned by a live streaming producer is unknown.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the duration of the producer regardless of in and out points
 */

mlt_position mlt_producer_get_length(mlt_producer self)
{
    return mlt_properties_get_position(MLT_PRODUCER_PROPERTIES(self), "length");
}

/** Get the total, unedited length of the producer as a time string.
 *
 * The value returned by a live streaming producer is unknown.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param format the time value format
 * \return the duration of the producer regardless of in and out points
 */

char *mlt_producer_get_length_time(mlt_producer self, mlt_time_format format)
{
    return mlt_properties_get_time(MLT_PRODUCER_PROPERTIES(self), "length", format);
}

/** Prepare for next frame.
 *
 * Advance the play out position. If the speed is less than zero, it will
 * move the play out position in the reverse direction.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 */

void mlt_producer_prepare_next(mlt_producer self)
{
    if (mlt_producer_get_speed(self) != 0)
        mlt_producer_seek(self, mlt_producer_position(self) + mlt_producer_get_speed(self));
}

/** Get a frame.
 *
 * This is the implementation of the \p get_frame virtual function.
 * It requests a new frame object from the actual producer for the current
 * play out position. The producer and its filters can add information and
 * operations to the frame object in their get_frame handlers.
 *
 * \private \memberof mlt_producer_s
 * \param service a service
 * \param[out] frame a frame by reference
 * \param index as determined by the actual producer
 * \return true if there was an error
 * \todo Learn more about the details and document how certain properties affect
 * its behavior.
 */

static int producer_get_frame(mlt_service service, mlt_frame_ptr frame, int index)
{
    int result = 1;
    mlt_producer self = service != NULL ? service->child : NULL;

    if (self != NULL && !mlt_producer_is_cut(self)) {
        // Get the properties of this producer
        mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);

        // Determine eof handling
        char *eof = mlt_properties_get(MLT_PRODUCER_PROPERTIES(self), "eof");

        // Get the speed of the producer
        double speed = mlt_producer_get_speed(self);

        // We need to use the clone if it's specified
        mlt_producer clone = mlt_properties_get_data(properties, "use_clone", NULL);

        // If no clone is specified, use self
        clone = clone == NULL ? self : clone;

        // A properly instatiated producer will have a get_frame method...
        if (self->get_frame == NULL
            || (eof && !strcmp(eof, "continue")
                && mlt_producer_position(self) > mlt_producer_get_out(self))) {
            // Generate a test frame
            *frame = mlt_frame_init(service);

            // Set the position
            result = mlt_frame_set_position(*frame, mlt_producer_position(self));

            // Mark as a test card
            mlt_properties_set_int(MLT_FRAME_PROPERTIES(*frame), "test_image", 1);
            mlt_properties_set_int(MLT_FRAME_PROPERTIES(*frame), "test_audio", 1);

            // Calculate the next position
            mlt_producer_prepare_next(self);
        } else {
            // Get the frame from the implementation
            result = self->get_frame(clone, frame, index);
        }

        // Copy the fps and speed of the producer onto the frame
        properties = MLT_FRAME_PROPERTIES(*frame);
        mlt_properties_set_double(properties, "_speed", speed);
        mlt_properties_set_int(properties, "test_audio", mlt_frame_is_test_audio(*frame));
        mlt_properties_set_int(properties, "test_image", mlt_frame_is_test_card(*frame));
        if (mlt_properties_get_data(properties, "_producer", NULL) == NULL)
            mlt_properties_set_data(properties, "_producer", service, 0, NULL, NULL);
    } else if (self != NULL) {
        // Get the speed of the cut
        double speed = mlt_producer_get_speed(self);

        // Get the parent of the cut
        mlt_producer parent = mlt_producer_cut_parent(self);

        // Get the properties of the parent
        mlt_properties parent_properties = MLT_PRODUCER_PROPERTIES(parent);

        // Get the properties of the cut
        mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);

        // Determine the clone index
        int clone_index = mlt_properties_get_int(properties, "_clone");

        // Determine the clone to use
        mlt_producer clone = self;

        if (clone_index > 0) {
            char key[25];
            sprintf(key, "_clone.%d", clone_index - 1);
            clone = mlt_properties_get_data(MLT_PRODUCER_PROPERTIES(mlt_producer_cut_parent(self)),
                                            key,
                                            NULL);
            if (clone == NULL)
                mlt_log(service, MLT_LOG_ERROR, "requested clone doesn't exist %d\n", clone_index);
            clone = clone == NULL ? self : clone;
        } else {
            clone = parent;
        }

        // We need to seek to the correct position in the clone
        mlt_producer_seek(clone,
                          mlt_producer_get_in(self)
                              + mlt_properties_get_int(properties, "_position"));

        // Assign the clone property to the parent
        mlt_properties_set_data(parent_properties, "use_clone", clone, 0, NULL, NULL);

        // Now get the frame from the parents service
        result = mlt_service_get_frame(MLT_PRODUCER_SERVICE(parent), frame, index);

        // We're done with the clone now
        mlt_properties_set_data(parent_properties, "use_clone", NULL, 0, NULL, NULL);

        // This is useful and required by always_active transitions to determine in/out points of the cut
        if (mlt_properties_get_data(MLT_FRAME_PROPERTIES(*frame), "_producer", NULL)
            == MLT_PRODUCER_SERVICE(parent))
            mlt_properties_set_data(MLT_FRAME_PROPERTIES(*frame), "_producer", self, 0, NULL, NULL);

        mlt_properties_set_double(MLT_FRAME_PROPERTIES(*frame), "_speed", speed);
        mlt_producer_prepare_next(self);
    } else {
        *frame = mlt_frame_init(service);
        result = 0;
    }

    // Pass on all meta properties from the producer/cut on to the frame
    if (*frame != NULL && self != NULL) {
        mlt_properties p_props = MLT_PRODUCER_PROPERTIES(self);
        mlt_properties f_props = MLT_FRAME_PROPERTIES(*frame);
        mlt_properties_lock(p_props);
        mlt_properties_copy(f_props, p_props, "meta.");
        mlt_properties_pass(f_props, p_props, "set.");
        mlt_properties_unlock(p_props);
    }

    return result;
}

/** Attach a filter.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param filter the filter to attach
 * \return true if there was an error
 */

int mlt_producer_attach(mlt_producer self, mlt_filter filter)
{
    return mlt_service_attach(MLT_PRODUCER_SERVICE(self), filter);
}

/** Detach a filter.
 *
 * \public \memberof mlt_producer_s
 * \param self a service
 * \param filter the filter to detach
 * \return true if there was an error
 */

int mlt_producer_detach(mlt_producer self, mlt_filter filter)
{
    return mlt_service_detach(MLT_PRODUCER_SERVICE(self), filter);
}

/** Retrieve a filter.
 *
 * \public \memberof mlt_producer_s
 * \param self a service
 * \param index which filter to retrieve
 * \return the filter or null if there was an error
 */

mlt_filter mlt_producer_filter(mlt_producer self, int index)
{
    return mlt_service_filter(MLT_PRODUCER_SERVICE(self), index);
}

/** Clone a producer.
 *
 * \private \memberof mlt_producer_s
 * \param self a producer
 * \return a new producer that is a copy of \p self
 * \see mlt_producer_set_clones
 */

static mlt_producer mlt_producer_clone(mlt_producer self)
{
    mlt_producer clone = NULL;
    mlt_properties properties = MLT_PRODUCER_PROPERTIES(self);
    char *resource = mlt_properties_get(properties, "resource");
    char *service = mlt_properties_get(properties, "mlt_service");
    mlt_profile profile = mlt_service_profile(MLT_PRODUCER_SERVICE(self));

    mlt_events_block(mlt_factory_event_object(), mlt_factory_event_object());

    if (service != NULL)
        clone = mlt_factory_producer(profile, service, resource);

    if (clone == NULL && resource != NULL)
        clone = mlt_factory_producer(profile, NULL, resource);

    if (clone != NULL)
        mlt_properties_inherit(MLT_PRODUCER_PROPERTIES(clone), properties);

    mlt_events_unblock(mlt_factory_event_object(), mlt_factory_event_object());

    return clone;
}

/** Create clones.
 *
 * \private \memberof mlt_producer_s
 * \param self a producer
 * \param clones the number of copies to make
 * \see mlt_producer_optimise
 */

static void mlt_producer_set_clones(mlt_producer self, int clones)
{
    mlt_producer parent = mlt_producer_cut_parent(self);
    mlt_properties properties = MLT_PRODUCER_PROPERTIES(parent);
    int existing = mlt_properties_get_int(properties, "_clones");
    int i = 0;
    char key[25];

    // If the number of existing clones is different, then create/remove as necessary
    if (existing != clones) {
        if (existing < clones) {
            for (i = existing; i < clones; i++) {
                mlt_producer clone = mlt_producer_clone(parent);
                sprintf(key, "_clone.%d", i);
                mlt_properties_set_data(properties,
                                        key,
                                        clone,
                                        0,
                                        (mlt_destructor) mlt_producer_close,
                                        NULL);
            }
        } else {
            for (i = clones; i < existing; i++) {
                sprintf(key, "_clone.%d", i);
                mlt_properties_set_data(properties, key, NULL, 0, NULL, NULL);
            }
        }
    }

    // Ensure all properties on the parent are passed to the clones
    for (i = 0; i < clones; i++) {
        mlt_producer clone = NULL;
        sprintf(key, "_clone.%d", i);
        clone = mlt_properties_get_data(properties, key, NULL);
        if (clone != NULL)
            mlt_properties_pass(MLT_PRODUCER_PROPERTIES(clone), properties, "");
    }

    // Update the number of clones on the properties
    mlt_properties_set_int(properties, "_clones", clones);
}

/** \brief private to mlt_producer_s, used by mlt_producer_optimise() */

typedef struct
{
    int multitrack;
    int track;
    int position;
    int length;
    int offset;
} track_info;

/** \brief private to mlt_producer_s, used by mlt_producer_optimise() */

typedef struct
{
    mlt_producer cut;
    int start;
    int end;
} clip_references;

static int intersect(clip_references *a, clip_references *b)
{
    int diff = (a->start - b->start) + (a->end - b->end);
    return diff >= 0 && diff < (a->end - a->start + 1);
}

static int push(mlt_parser self, int multitrack, int track, int position)
{
    mlt_properties properties = mlt_parser_properties(self);
    mlt_deque stack = mlt_properties_get_data(properties, "stack", NULL);
    track_info *info = malloc(sizeof(track_info));
    info->multitrack = multitrack;
    info->track = track;
    info->position = position;
    info->length = 0;
    info->offset = 0;
    return mlt_deque_push_back(stack, info);
}

static track_info *pop(mlt_parser self)
{
    mlt_properties properties = mlt_parser_properties(self);
    mlt_deque stack = mlt_properties_get_data(properties, "stack", NULL);
    return mlt_deque_pop_back(stack);
}

static track_info *peek(mlt_parser self)
{
    mlt_properties properties = mlt_parser_properties(self);
    mlt_deque stack = mlt_properties_get_data(properties, "stack", NULL);
    return mlt_deque_peek_back(stack);
}

static int on_start_multitrack(mlt_parser self, mlt_multitrack object)
{
    track_info *info = peek(self);
    return push(self, info->multitrack++, info->track, info->position);
}

static int on_start_track(mlt_parser self)
{
    track_info *info = peek(self);
    info->position -= info->offset;
    info->length -= info->offset;
    return push(self, info->multitrack, info->track++, info->position);
}

static int on_start_producer(mlt_parser self, mlt_producer object)
{
    mlt_properties properties = mlt_parser_properties(self);
    mlt_properties producers = mlt_properties_get_data(properties, "producers", NULL);
    mlt_producer parent = mlt_producer_cut_parent(object);
    if (mlt_service_identify((mlt_service) mlt_producer_cut_parent(object))
            == mlt_service_producer_type
        && mlt_producer_is_cut(object)) {
        int ref_count = 0;
        clip_references *old_refs = NULL;
        clip_references *refs = NULL;
        char key[50];
        int count = 0;
        track_info *info = peek(self);
        sprintf(key, "%p", parent);
        mlt_properties_get_data(producers, key, &count);
        mlt_properties_set_data(producers, key, parent, ++count, NULL, NULL);
        old_refs = mlt_properties_get_data(properties, key, &ref_count);
        refs = malloc((ref_count + 1) * sizeof(clip_references));
        if (old_refs != NULL)
            memcpy(refs, old_refs, ref_count * sizeof(clip_references));
        mlt_properties_set_int(MLT_PRODUCER_PROPERTIES(object), "_clone", -1);
        refs[ref_count].cut = object;
        refs[ref_count].start = info->position;
        refs[ref_count].end = info->position + mlt_producer_get_playtime(object) - 1;
        mlt_properties_set_data(properties, key, refs, ++ref_count, free, NULL);
        info->position += mlt_producer_get_playtime(object);
        info->length += mlt_producer_get_playtime(object);
    }
    return 0;
}

static int on_end_track(mlt_parser self)
{
    track_info *track = pop(self);
    track_info *multi = peek(self);
    multi->length += track->length;
    multi->position += track->length;
    multi->offset = track->length;
    free(track);
    return 0;
}

static int on_end_multitrack(mlt_parser self, mlt_multitrack object)
{
    track_info *multi = pop(self);
    track_info *track = peek(self);
    track->position += multi->length;
    track->length += multi->length;
    free(multi);
    return 0;
}

/** Optimise for overlapping cuts from the same clip.
 *
 * \todo learn more about this
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return true if there was an error
 */

int mlt_producer_optimise(mlt_producer self)
{
    int error = 1;
    mlt_parser parser = mlt_parser_new();
    if (parser != NULL) {
        int i = 0, j = 0, k = 0;
        mlt_properties properties = mlt_parser_properties(parser);
        mlt_properties producers = mlt_properties_new();
        mlt_deque stack = mlt_deque_init();
        mlt_properties_set_data(properties,
                                "producers",
                                producers,
                                0,
                                (mlt_destructor) mlt_properties_close,
                                NULL);
        mlt_properties_set_data(properties,
                                "stack",
                                stack,
                                0,
                                (mlt_destructor) mlt_deque_close,
                                NULL);
        parser->on_start_producer = on_start_producer;
        parser->on_start_track = on_start_track;
        parser->on_end_track = on_end_track;
        parser->on_start_multitrack = on_start_multitrack;
        parser->on_end_multitrack = on_end_multitrack;
        push(parser, 0, 0, 0);
        mlt_parser_start(parser, MLT_PRODUCER_SERVICE(self));
        free(pop(parser));
        for (k = 0; k < mlt_properties_count(producers); k++) {
            char *name = mlt_properties_get_name(producers, k);
            int count = 0;
            int clones = 0;
            int max_clones = 0;
            mlt_producer producer = mlt_properties_get_data_at(producers, k, &count);
            if (producer != NULL && count > 1) {
                clip_references *refs = mlt_properties_get_data(properties, name, &count);
                for (i = 0; i < count; i++) {
                    clones = 0;
                    for (j = i + 1; j < count; j++) {
                        if (intersect(&refs[i], &refs[j])) {
                            clones++;
                            mlt_properties_set_int(MLT_PRODUCER_PROPERTIES(refs[j].cut),
                                                   "_clone",
                                                   clones);
                        }
                    }
                    if (clones > max_clones)
                        max_clones = clones;
                }

                for (i = 0; i < count; i++) {
                    mlt_producer cut = refs[i].cut;
                    if (mlt_properties_get_int(MLT_PRODUCER_PROPERTIES(cut), "_clone") == -1)
                        mlt_properties_set_int(MLT_PRODUCER_PROPERTIES(cut), "_clone", 0);
                }

                mlt_producer_set_clones(producer, max_clones);
            } else if (producer != NULL) {
                clip_references *refs = mlt_properties_get_data(properties, name, &count);
                for (i = 0; i < count; i++) {
                    mlt_producer cut = refs[i].cut;
                    mlt_properties_set_int(MLT_PRODUCER_PROPERTIES(cut), "_clone", 0);
                }
                mlt_producer_set_clones(producer, 0);
            }
        }
        mlt_parser_close(parser);
    }
    return error;
}

/** Close the producer.
 *
 * Destroys the producer and deallocates its resources managed by its
 * properties list. This will call the close virtual function. Therefore, a
 * subclass that defines its own close function should set its virtual close
 * function to NULL prior to calling this to avoid circular calls.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 */

void mlt_producer_close(mlt_producer self)
{
    if (self != NULL && mlt_properties_dec_ref(MLT_PRODUCER_PROPERTIES(self)) <= 0) {
        self->parent.close = NULL;

        if (self->close != NULL) {
            self->close(self->close_object);
        } else {
            int destroy = mlt_producer_is_cut(self);

#if _MLT_PRODUCER_CHECKS_ == 1
            // Show debug info
            mlt_properties_debug(MLT_PRODUCER_PROPERTIES(self), "Producer closing", stderr);
#endif

#ifdef _MLT_PRODUCER_CHECKS_
            // Show current stats - these should match when the app is closed
            mlt_log(MLT_PRODUCER_SERVICE(self),
                    MLT_LOG_DEBUG,
                    "Producers created %d, destroyed %d\n",
                    producers_created,
                    ++producers_destroyed);
#endif

            mlt_service_close(&self->parent);

            if (destroy)
                free(self);
        }
    }
}

/*
 * Boost implementation of timegm()
 * (C) Copyright Howard Hinnant
 * (C) Copyright 2010-2011 Vicente J. Botet Escriba
 */

static inline int32_t is_leap(int32_t year)
{
    if (year % 400 == 0)
        return 1;
    if (year % 100 == 0)
        return 0;
    if (year % 4 == 0)
        return 1;
    return 0;
}

static inline int32_t days_from_0(int32_t year)
{
    year--;
    return 365 * year + (year / 400) - (year / 100) + (year / 4);
}

static inline int32_t days_from_1970(int32_t year)
{
    const int days_from_0_to_1970 = days_from_0(1970);
    return days_from_0(year) - days_from_0_to_1970;
}

static inline int32_t days_from_1jan(int32_t year, int32_t month, int32_t day)
{
    static const int32_t days[2][12] = {{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334},
                                        {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335}};
    return days[is_leap(year)][month - 1] + day - 1;
}

static inline time_t internal_timegm(struct tm const *t)
{
    int year = t->tm_year + 1900;
    int month = t->tm_mon;
    if (month > 11) {
        year += month / 12;
        month %= 12;
    } else if (month < 0) {
        int years_diff = (-month + 11) / 12;
        year -= years_diff;
        month += 12 * years_diff;
    }
    month++;
    int day = t->tm_mday;
    int day_of_year = days_from_1jan(year, month, day);
    int days_since_epoch = days_from_1970(year) + day_of_year;

    time_t seconds_in_day = 3600 * 24;
    time_t result = seconds_in_day * days_since_epoch + 3600 * t->tm_hour + 60 * t->tm_min
                    + t->tm_sec;

    return result;
}

/* End of Boost implementation of timegm(). */

/** Get the creation time for the producer.
 *
 * The creation_time value is searched in the following order:
 *   - A "creation_time" property in ISO 8601 format (yyyy-mm-ddThh:mm:ss)
 *   - A "meta.attr.com.apple.quicktime.creationdate.markup" property in ISO 8601 format
 *   - A "meta.attr.creation_time.markup" property in ISO 8601 format
 *   - If the producer has a resource that is a file, the mtime of the file
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \return the creation time of the producer in seconds since the epoch
 */

int64_t mlt_producer_get_creation_time(mlt_producer self)
{
    mlt_producer producer = mlt_producer_cut_parent(self);
    // Prefer creation_time producer property if present
    char *datestr = mlt_properties_get(MLT_PRODUCER_PROPERTIES(producer), "creation_time");
    if (!datestr) {
        // Fall back to quicktime creationdate metadata (common for .mov files)
        // creationdate is preferred over creation_time metadata because
        // creation_time may be recalculated if the device re-encodes the file.
        datestr = mlt_properties_get(MLT_PRODUCER_PROPERTIES(producer),
                                     "meta.attr.com.apple.quicktime.creationdate.markup");
    }
    if (!datestr) {
        // Fall back to creation_time metadata (common for most media handled by ffmpeg)
        datestr = mlt_properties_get(MLT_PRODUCER_PROPERTIES(producer),
                                     "meta.attr.creation_time.markup");
    }
    if (datestr) {
        struct tm time_info = {0};
        double seconds;
        char offset_indicator = 0;
        int hour_offset = 0;
        int min_offset = 0;
        int ret = sscanf(datestr,
                         "%04d-%02d-%02dT%02d:%02d:%lf%c%02d%02d",
                         &time_info.tm_year,
                         &time_info.tm_mon,
                         &time_info.tm_mday,
                         &time_info.tm_hour,
                         &time_info.tm_min,
                         &seconds,
                         &offset_indicator,
                         &hour_offset,
                         &min_offset);

        if (ret >= 6) {
            time_info.tm_sec = (int) seconds;
            time_info.tm_mon -= 1;
            time_info.tm_year -= 1900;
            time_info.tm_isdst = -1;
            int64_t milliseconds = (int64_t) internal_timegm(&time_info) * 1000;
            milliseconds += (seconds - (double) time_info.tm_sec) * 1000.0;

            // Apply time zone offset if present.
            if (ret == 9 && offset_indicator == '-') {
                milliseconds += ((hour_offset * 60) + min_offset) * 60000;
            } else if (ret == 9 && offset_indicator == '+') {
                milliseconds -= ((hour_offset * 60) + min_offset) * 60000;
            }
            return milliseconds;
        }
    }

    // Fall back to file modification time.
    char *resource = mlt_properties_get(MLT_PRODUCER_PROPERTIES(producer), "resource");
    if (!resource) {
        resource = mlt_properties_get(MLT_PRODUCER_PROPERTIES(producer), "warp_resource");
    }
    if (resource) {
        struct stat file_info;
        if (!stat(resource, &file_info)) {
            return (int64_t) file_info.st_mtime * 1000;
        }
    }

    return 0;
}

/** Set the creation time for the producer.
 *
 * A "creation_time" property in ISO 8601 format (yyyy-mm-ddThh:mm:ss) will be
 * applied to the producer.
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
 * \param creation_time the creation time of the producer in seconds since the epoch
 */

void mlt_producer_set_creation_time(mlt_producer self, int64_t creation_time)
{
    time_t time = creation_time / 1000;
    mlt_producer parent = mlt_producer_cut_parent(self);
    char *datestr = calloc(1, 20);
    strftime(datestr, 20, "%Y-%m-%dT%H:%M:%S", gmtime(&time));
    mlt_properties_set(MLT_PRODUCER_PROPERTIES(parent), "creation_time", datestr);
    free(datestr);
}

/** Probe the producer to publish metadata properties.
 *
 * After this call the producer will publish meta.media properties
 *
 * \public \memberof mlt_producer_s
 * \param self a producer
  * \return true on error
 */

int mlt_producer_probe(mlt_producer self)
{
    if (self) {
        int (*probe)(mlt_producer) = mlt_properties_get_data(MLT_PRODUCER_PROPERTIES(self),
                                                             "mlt_producer_probe",
                                                             NULL);
        if (probe)
            return probe(self);
    }
    return 0;
}
