/*
 * filter_timer.c -- timer text overlay filter
 * Copyright (C) 2018-2019 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 <framework/mlt.h>

#include <math.h>
#include <stdlib.h>
#include <string.h>

#define MAX_TEXT_LEN 512

double time_to_seconds(char *time)
{
    int hours = 0;
    int mins = 0;
    double secs = 0;
    if (time)
        sscanf(time, "%d:%d:%lf", &hours, &mins, &secs);
    return (hours * 60.0 * 60.0) + (mins * 60.0) + secs;
}

static void get_timer_str(mlt_filter filter, mlt_frame frame, char *text)
{
    mlt_properties properties = MLT_FILTER_PROPERTIES(filter);
    double filter_speed = mlt_properties_get_double(properties, "speed");
    mlt_position current_frame = mlt_filter_get_position(filter, frame) * filter_speed;
    char *direction = mlt_properties_get(properties, "direction");
    double timer_start = time_to_seconds(mlt_properties_get(properties, "start"));
    double timer_duration = time_to_seconds(mlt_properties_get(properties, "duration"));
    double timer_offset = time_to_seconds(mlt_properties_get(properties, "offset"));
    double value = time_to_seconds(
        mlt_properties_frames_to_time(properties, current_frame, mlt_time_clock));

    if (timer_duration <= 0.0) {
        // "duration" of zero means entire length of the filter.
        mlt_position filter_length = mlt_filter_get_length2(filter, frame) - 1;
        double filter_duration = time_to_seconds(
            mlt_properties_frames_to_time(properties, filter_length, mlt_time_clock));
        timer_duration = (filter_duration - timer_start) * filter_speed;
    }

    if (value < timer_start * filter_speed) {
        // Hold at 0 until start time.
        value = 0.0;
    } else {
        value = value - timer_start * filter_speed;
        if (value > timer_duration) {
            // Hold at duration after the timer has elapsed.
            value = timer_duration;
        }
    }

    // Apply direction.
    if (direction && !strcmp(direction, "down")) {
        value = timer_duration - value;
    }

    // Apply offset
    value += timer_offset;

    int hours = value / (60 * 60);
    int mins = (value / 60) - (hours * 60);
    double secs = value - (double) (mins * 60) - (double) (hours * 60 * 60);
    char *format = mlt_properties_get(properties, "format");

    if (!strcmp(format, "HH:MM:SS")) {
        snprintf(text, MAX_TEXT_LEN, "%02d:%02d:%02d", hours, mins, (int) floor(secs));
    } else if (!strcmp(format, "HH:MM:SS.S")) {
        snprintf(text, MAX_TEXT_LEN, "%02d:%02d:%04.1f", hours, mins, floor(secs * 10.0) / 10.0);
    } else if (!strcmp(format, "MM:SS")) {
        snprintf(text, MAX_TEXT_LEN, "%02d:%02d", hours * 60 + mins, (int) floor(secs));
    } else if (!strcmp(format, "MM:SS.SS")) {
        snprintf(text, MAX_TEXT_LEN, "%02d:%05.2f", hours * 60 + mins, floor(secs * 100.0) / 100.0);
    } else if (!strcmp(format, "MM:SS.SSS")) {
        snprintf(text, MAX_TEXT_LEN, "%02d:%06.3f", hours * 60 + mins, floor(secs * 1000.0) / 1000.0);
    } else if (!strcmp(format, "SS")) {
        snprintf(text, MAX_TEXT_LEN, "%02d", (int) floor(value));
    } else if (!strcmp(format, "SS.S")) {
        snprintf(text, MAX_TEXT_LEN, "%04.1f", floor(value * 10.0) / 10.0);
    } else if (!strcmp(format, "SS.SS")) {
        snprintf(text, MAX_TEXT_LEN, "%05.2f", floor(value * 100.0) / 100.0);
    } else if (!strcmp(format, "SS.SSS")) {
        snprintf(text, MAX_TEXT_LEN, "%06.3f", floor(value * 1000.0) / 1000.0);
    }
}

static mlt_frame filter_process(mlt_filter filter, mlt_frame frame)
{
    mlt_properties properties = MLT_FILTER_PROPERTIES(filter);
    mlt_filter text_filter = mlt_properties_get_data(properties, "_text_filter", NULL);
    mlt_properties text_filter_properties
        = mlt_frame_unique_properties(frame, MLT_FILTER_SERVICE(text_filter));
    char *result = calloc(1, MAX_TEXT_LEN);
    get_timer_str(filter, frame, result);
    mlt_properties_set(text_filter_properties, "argument", result);
    free(result);
    mlt_properties_pass_list(
        text_filter_properties,
        properties,
        "geometry family size weight style fgcolour bgcolour olcolour pad halign valign outline");
    mlt_filter_set_in_and_out(text_filter, mlt_filter_get_in(filter), mlt_filter_get_out(filter));
    return mlt_filter_process(text_filter, frame);
}

/** Constructor for the filter.
*/
mlt_filter filter_timer_init(mlt_profile profile, mlt_service_type type, const char *id, char *arg)
{
    mlt_filter filter = mlt_filter_new();
    mlt_filter text_filter = mlt_factory_filter(profile, "qtext", NULL);

    if (!text_filter)
        text_filter = mlt_factory_filter(profile, "text", NULL);

    if (!text_filter)
        mlt_log_warning(MLT_FILTER_SERVICE(filter), "Unable to create text filter.\n");

    if (filter && text_filter) {
        mlt_properties my_properties = MLT_FILTER_PROPERTIES(filter);

        // Register the text filter for reuse/destruction
        mlt_properties_set_data(my_properties,
                                "_text_filter",
                                text_filter,
                                0,
                                (mlt_destructor) mlt_filter_close,
                                NULL);

        // Assign default values
        mlt_properties_set(my_properties, "format", "SS.SS");
        mlt_properties_set(my_properties, "start", "00:00:00.000");
        mlt_properties_set(my_properties, "duration", "00:10:00.000");
        mlt_properties_set(my_properties, "offset", "00:00:00.000");
        mlt_properties_set_double(my_properties, "speed", 1.0);
        mlt_properties_set(my_properties, "direction", "up");
        mlt_properties_set(my_properties, "geometry", "0%/0%:100%x100%:100%");
        mlt_properties_set(my_properties, "family", "Sans");
        mlt_properties_set(my_properties, "size", "48");
        mlt_properties_set(my_properties, "weight", "400");
        mlt_properties_set(my_properties, "style", "normal");
        mlt_properties_set(my_properties, "fgcolour", "0x000000ff");
        mlt_properties_set(my_properties, "bgcolour", "0x00000020");
        mlt_properties_set(my_properties, "olcolour", "0x00000000");
        mlt_properties_set(my_properties, "pad", "0");
        mlt_properties_set(my_properties, "halign", "left");
        mlt_properties_set(my_properties, "valign", "top");
        mlt_properties_set(my_properties, "outline", "0");
        mlt_properties_set_int(my_properties, "_filter_private", 1);

        filter->process = filter_process;
    } else {
        if (filter) {
            mlt_filter_close(filter);
        }

        if (text_filter) {
            mlt_filter_close(text_filter);
        }

        filter = NULL;
    }
    return filter;
}
