/*
 * filter_audiolevel.cpp -- audio level visualization filter
 * Copyright (c) 2021-2022 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 "common.h"
#include "graph.h"
#include <cstring> // memset
#include <framework/mlt.h>
#include <framework/mlt_log.h>
#include <math.h> //pow
#include <QImage>
#include <QPainter>
#include <QVector>

namespace {
// Private Types
typedef struct
{
    mlt_filter levels_filter;
    int preprocess_warned;
} private_data;
} // namespace

static int filter_get_audio(mlt_frame frame,
                            void **buffer,
                            mlt_audio_format *format,
                            int *frequency,
                            int *channels,
                            int *samples)
{
    mlt_filter filter = (mlt_filter) mlt_frame_pop_audio(frame);
    private_data *pdata = (private_data *) filter->child;

    // Create the audiolevel filter the first time.
    if (!pdata->levels_filter) {
        mlt_profile profile = mlt_service_profile(MLT_FILTER_SERVICE(filter));
        pdata->levels_filter = mlt_factory_filter(profile, "audiolevel", NULL);
        if (!pdata->levels_filter) {
            mlt_log_warning(MLT_FILTER_SERVICE(filter), "Unable to create audiolevel filter.\n");
            return 1;
        }
    }

    // The service must stay locked while using the private data
    mlt_service_lock(MLT_FILTER_SERVICE(filter));

    // Perform audio level processing on the frame
    mlt_filter_process(pdata->levels_filter, frame);
    mlt_frame_get_audio(frame, buffer, format, frequency, channels, samples);

    mlt_service_unlock(MLT_FILTER_SERVICE(filter));

    return 0;
}

double get_level_from_frame(mlt_frame frame, int channel)
{
    char prop_str[30];
    snprintf(prop_str, 30, "meta.media.audio_level.%d", channel);
    return mlt_properties_get_double(MLT_FRAME_PROPERTIES(frame), prop_str);
}

static void convert_levels(mlt_filter filter, mlt_frame frame, int channels, float *levels)
{
    mlt_properties filter_properties = MLT_FILTER_PROPERTIES(filter);
    mlt_properties frame_properties = MLT_FRAME_PROPERTIES(frame);
    int reverse = mlt_properties_get_int(filter_properties, "reverse");
    int real_channels = mlt_properties_get_int(frame_properties, "audio_channels");
    if (real_channels == 0)
        real_channels = 1;

    int chan_index = 0;
    for (chan_index = 0; chan_index < channels; chan_index++) {
        double level = 0.0;
        if (channels == 1) {
            // For 1 channel display, average all channel levels
            int real_chan_index = 0;
            for (real_chan_index = 0; real_chan_index < real_channels; real_chan_index++) {
                level += get_level_from_frame(frame, real_chan_index);
            }
            level /= real_channels;
        } else {
            int real_chan_index = chan_index % real_channels;
            level = get_level_from_frame(frame, real_chan_index);
        }

        if (reverse) {
            levels[channels - chan_index - 1] = level;
        } else {
            levels[chan_index] = level;
        }
    }
}

static void draw_levels(mlt_filter filter, mlt_frame frame, QImage *qimg, int width, int height)
{
    mlt_properties filter_properties = MLT_FILTER_PROPERTIES(filter);
    mlt_position position = mlt_filter_get_position(filter, frame);
    mlt_position length = mlt_filter_get_length2(filter, frame);
    mlt_profile profile = mlt_service_profile(MLT_FILTER_SERVICE(filter));
    mlt_rect rect = mlt_properties_anim_get_rect(filter_properties, "rect", position, length);
    if (strchr(mlt_properties_get(filter_properties, "rect"), '%')) {
        rect.x *= qimg->width();
        rect.w *= qimg->width();
        rect.y *= qimg->height();
        rect.h *= qimg->height();
    }
    double scale = mlt_profile_scale_width(profile, width);
    rect.x *= scale;
    rect.w *= scale;
    scale = mlt_profile_scale_height(profile, height);
    rect.y *= scale;
    rect.h *= scale;
    char *graph_type = mlt_properties_get(filter_properties, "type");
    int mirror = mlt_properties_get_int(filter_properties, "mirror");
    int segments = mlt_properties_anim_get_int(filter_properties, "segments", position, length);
    int segment_gap = mlt_properties_anim_get_int(filter_properties, "segment_gap", position, length)
                      * scale;
    int segment_width = mlt_properties_anim_get_int(filter_properties, "thickness", position, length)
                        * scale;
    QVector<QColor> colors = get_graph_colors(filter_properties, position, length);

    QRectF r(rect.x, rect.y, rect.w, rect.h);
    QPainter p(qimg);

    if (mirror) {
        // Draw two half rectangle instead of one full rectangle.
        r.setHeight(r.height() / 2.0);
    }

    setup_graph_painter(p, r, filter_properties, position, length);
    setup_graph_pen(p, r, filter_properties, scale, position, length);

    int channels = mlt_properties_anim_get_int(filter_properties, "channels", position, length);
    if (channels == 0) {
        // "0" means use number of channels in the frame
        channels = mlt_properties_get_int(MLT_FRAME_PROPERTIES(frame), "audio_channels");
    }
    if (channels == 0)
        channels = 1;
    float *levels = (float *) mlt_pool_alloc(channels * sizeof(float));

    convert_levels(filter, frame, channels, levels);

    if (graph_type && graph_type[0] == 'b') {
        paint_bar_graph(p, r, channels, levels);
    } else {
        paint_segment_graph(p, r, channels, levels, colors, segments, segment_gap, segment_width);
    }

    if (mirror) {
        // Second rectangle is mirrored.
        p.translate(0, r.y() * 2 + r.height() * 2);
        p.scale(1, -1);
        if (graph_type && graph_type[0] == 'b') {
            paint_bar_graph(p, r, channels, levels);
        } else {
            paint_segment_graph(p, r, channels, levels, colors, segments, segment_gap, segment_width);
        }
    }

    mlt_pool_release(levels);

    p.end();
}
/** Get the image.
*/
static int filter_get_image(mlt_frame frame,
                            uint8_t **image,
                            mlt_image_format *format,
                            int *width,
                            int *height,
                            int writable)
{
    int error = 0;
    mlt_filter filter = (mlt_filter) mlt_frame_pop_service(frame);
    private_data *pdata = (private_data *) filter->child;
    mlt_properties frame_properties = MLT_FRAME_PROPERTIES(frame);

    if (mlt_properties_get(frame_properties, "meta.media.audio_level.0")) {
        // Get the current image
        *format = mlt_image_rgba;
        error = mlt_frame_get_image(frame, image, format, width, height, 1);

        // Draw the audio levels
        if (!error) {
            QImage qimg(*width, *height, QImage::Format_ARGB32);
            convert_mlt_to_qimage_rgba(*image, &qimg, *width, *height);
            draw_levels(filter, frame, &qimg, *width, *height);
            convert_qimage_to_mlt_rgba(&qimg, *image, *width, *height);
        }
    } else {
        if (pdata->preprocess_warned++ == 2) {
            // This filter depends on the consumer processing the audio before
            // the video.
            mlt_log_warning(MLT_FILTER_SERVICE(filter), "Audio not preprocessed.\n");
        }
        mlt_frame_get_image(frame, image, format, width, height, writable);
    }

    return error;
}

/** Filter processing.
*/
static mlt_frame filter_process(mlt_filter filter, mlt_frame frame)
{
    if (mlt_frame_is_test_card(frame)) {
        // The producer does not generate video. This filter will create an
        // image on the producer's behalf.
        mlt_properties frame_properties = MLT_FRAME_PROPERTIES(frame);
        mlt_profile profile = mlt_service_profile(MLT_FILTER_SERVICE(filter));
        mlt_properties_set_int(frame_properties, "progressive", 1);
        mlt_properties_set_double(frame_properties, "aspect_ratio", mlt_profile_sar(profile));
        mlt_properties_set_int(frame_properties, "meta.media.width", profile->width);
        mlt_properties_set_int(frame_properties, "meta.media.height", profile->height);
        // Tell the framework that there really is an image.
        mlt_properties_set_int(frame_properties, "test_image", 0);
        // Push a callback to create the image.
        mlt_frame_push_get_image(frame, create_image);
    }

    mlt_frame_push_audio(frame, filter);
    mlt_frame_push_audio(frame, (void *) filter_get_audio);
    mlt_frame_push_service(frame, filter);
    mlt_frame_push_get_image(frame, filter_get_image);
    return frame;
}

static void filter_close(mlt_filter filter)
{
    private_data *pdata = (private_data *) filter->child;

    if (pdata) {
        mlt_filter_close(pdata->levels_filter);
        free(pdata);
    }
    filter->child = NULL;
    filter->close = NULL;
    filter->parent.close = NULL;
    mlt_service_close(&filter->parent);
}

/** Constructor for the filter.
*/

extern "C" {

mlt_filter filter_audiolevelgraph_init(mlt_profile profile,
                                       mlt_service_type type,
                                       const char *id,
                                       char *arg)
{
    mlt_filter filter = mlt_filter_new();
    private_data *pdata = (private_data *) calloc(1, sizeof(private_data));

    if (filter && pdata && createQApplicationIfNeeded(MLT_FILTER_SERVICE(filter))) {
        mlt_properties properties = MLT_FILTER_PROPERTIES(filter);
        mlt_properties_set_int(properties, "_filter_private", 1);
        mlt_properties_set(properties, "type", "bar");
        mlt_properties_set(properties, "bgcolor", "0x00000000");
        mlt_properties_set(properties, "color.1", "0xffffffff");
        mlt_properties_set(properties, "rect", "0% 0% 100% 100%");
        mlt_properties_set(properties, "thickness", "0");
        mlt_properties_set(properties, "fill", "0");
        mlt_properties_set(properties, "mirror", "0");
        mlt_properties_set(properties, "reverse", "0");
        mlt_properties_set(properties, "angle", "0");
        mlt_properties_set(properties, "gorient", "v");
        mlt_properties_set_int(properties, "channels", 2);
        mlt_properties_set_int(properties, "segment_gap", 10);

        pdata->levels_filter = 0;

        filter->close = filter_close;
        filter->process = filter_process;
        filter->child = pdata;
    } else {
        mlt_log_error(MLT_FILTER_SERVICE(filter), "Filter audio level graph failed\n");

        if (filter) {
            mlt_filter_close(filter);
        }

        if (pdata) {
            free(pdata);
        }

        filter = NULL;
    }
    return filter;
}
}
