/*
 * producer_image.c -- a Qt/QImage based producer for MLT
 * Copyright (C) 2006-2022 Meltytech, LLC
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU 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.
 */

#include "qimage_wrapper.h"
#include <framework/mlt_cache.h>
#include <framework/mlt_events.h>
#include <framework/mlt_producer.h>

#include <ctype.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>

static void load_filenames(producer_qimage self, mlt_properties producer_properties);
static int producer_get_frame(mlt_producer parent, mlt_frame_ptr frame, int index);
static void producer_close(mlt_producer parent);

static void refresh_length(mlt_properties properties, producer_qimage self)
{
    if (self->count > mlt_properties_get_int(properties, "length")
        || mlt_properties_get_int(properties, "autolength")) {
        int ttl = mlt_properties_get_int(properties, "ttl");
        mlt_position length = self->count * ttl;
        mlt_properties_set_position(properties, "length", length);
        mlt_properties_set_position(properties, "out", length - 1);
    }
}

static void on_property_changed(mlt_service owner, mlt_producer producer, mlt_event_data event_data)
{
    const char *name = mlt_event_data_to_string(event_data);
    if (name && !strcmp(name, "ttl"))
        refresh_length(MLT_PRODUCER_PROPERTIES(producer), producer->child);
}

mlt_producer producer_qimage_init(mlt_profile profile,
                                  mlt_service_type type,
                                  const char *id,
                                  char *filename)
{
    producer_qimage self = calloc(1, sizeof(struct producer_qimage_s));
    if (self != NULL && mlt_producer_init(&self->parent, self) == 0) {
        mlt_producer producer = &self->parent;

        // Get the properties interface
        mlt_properties properties = MLT_PRODUCER_PROPERTIES(&self->parent);

        // Initialize KDE image plugins and get supported animation frame count
        self->count = init_qimage(producer, filename);
        if (!self->count) {
            mlt_producer_close(producer);
            free(self);
            return NULL;
        }

        // Callback registration
        producer->get_frame = producer_get_frame;
        producer->close = (mlt_destructor) producer_close;

        // Set the default properties
        mlt_properties_set(properties, "resource", filename);
        mlt_properties_set_int(properties, "ttl", self->count > 1 ? 1 : 25);
        mlt_properties_set_int(properties, "aspect_ratio", 1);
        mlt_properties_set_int(properties, "meta.media.progressive", 1);
        mlt_properties_set_int(properties, "seekable", 1);

        // Validate the resource
        if (self->count == 1 && filename) {
            load_filenames(self, properties);
        } else {
            refresh_length(properties, self);
        }
        if (self->count) {
            mlt_frame frame = mlt_frame_init(MLT_PRODUCER_SERVICE(producer));
            if (frame) {
                mlt_properties frame_properties = MLT_FRAME_PROPERTIES(frame);
                mlt_properties_set_data(frame_properties, "producer_qimage", self, 0, NULL, NULL);
                mlt_frame_set_position(frame, mlt_producer_position(producer));
                int enable_caching = self->count == 1;
                refresh_qimage(self, frame, enable_caching);
                if (enable_caching) {
                    mlt_cache_item_close(self->qimage_cache);
                }
                mlt_frame_close(frame);
            }
        }
        if (self->current_width == 0) {
            producer_close(producer);
            producer = NULL;
        } else {
            mlt_events_listen(properties,
                              self,
                              "property-changed",
                              (mlt_listener) on_property_changed);
        }
        return producer;
    }
    free(self);
    return NULL;
}

static int load_svg(producer_qimage self, mlt_properties properties, const char *filename)
{
    int result = 0;

    // Read xml string
    if (strstr(filename, "<svg")) {
        make_tempfile(self, filename);
        result = 1;
    }
    return result;
}

static int load_sequence_deprecated(producer_qimage self,
                                    mlt_properties properties,
                                    const char *filename)
{
    int result = 0;
    const char *start;

    // Obtain filenames with pattern containing a begin value, e.g. foo%1234d.png
    if ((start = strchr(filename, '%'))) {
        const char *end = ++start;
        while (isdigit(*end))
            end++;
        if (end > start && (end[0] == 'd' || end[0] == 'i' || end[0] == 'u')) {
            int n = end - start;
            char *s = calloc(1, n + 1);
            strncpy(s, start, n);
            mlt_properties_set(properties, "begin", s);
            free(s);
            s = calloc(1, strlen(filename) + 2);
            strncpy(s, filename, start - filename);
            sprintf(s + (start - filename), ".%d%s", n, end);
            result = load_sequence_sprintf(self, properties, s);
            free(s);
        }
    }
    return result;
}

static int load_sequence_querystring(producer_qimage self,
                                     mlt_properties properties,
                                     const char *filename)
{
    int result = 0;

    // Obtain filenames with pattern and begin value in query string
    if (strchr(filename, '%') && strchr(filename, '?')) {
        // Split filename into pattern and query string
        char *s = strdup(filename);
        char *querystring = strrchr(s, '?');
        *querystring++ = '\0';
        if (strstr(filename, "begin="))
            mlt_properties_set(properties, "begin", strstr(querystring, "begin=") + 6);
        else if (strstr(filename, "begin:"))
            mlt_properties_set(properties, "begin", strstr(querystring, "begin:") + 6);
        // Coerce to an int value so serialization does not have any extra query string cruft
        mlt_properties_set_int(properties, "begin", mlt_properties_get_int(properties, "begin"));
        result = load_sequence_sprintf(self, properties, s);
        free(s);
    }
    return result;
}

static void load_filenames(producer_qimage self, mlt_properties properties)
{
    char *filename = mlt_properties_get(properties, "resource");
    self->filenames = mlt_properties_new();

    if (!load_svg(self, properties, filename)
        && !load_sequence_querystring(self, properties, filename)
        && !load_sequence_sprintf(self, properties, filename)
        && !load_sequence_deprecated(self, properties, filename) && !load_folder(self, filename)) {
        mlt_properties_set(self->filenames, "0", filename);
    }
    self->count = mlt_properties_count(self->filenames);
    refresh_length(properties, self);
}

static int producer_get_image(mlt_frame frame,
                              uint8_t **buffer,
                              mlt_image_format *format,
                              int *width,
                              int *height,
                              int writable)
{
    int error = 0;

    // Obtain properties of frame and producer
    mlt_properties properties = MLT_FRAME_PROPERTIES(frame);
    producer_qimage self = mlt_properties_get_data(properties, "producer_qimage", NULL);
    mlt_producer producer = &self->parent;

    // Use the width and height suggested by the rescale filter because we can do our own scaling.
    if (mlt_properties_get_int(properties, "rescale_width") > 0)
        *width = mlt_properties_get_int(properties, "rescale_width");
    if (mlt_properties_get_int(properties, "rescale_height") > 0)
        *height = mlt_properties_get_int(properties, "rescale_height");
    mlt_service_lock(MLT_PRODUCER_SERVICE(&self->parent));
    int enable_caching = (self->count <= 1
                          || mlt_properties_get_int(MLT_PRODUCER_PROPERTIES(producer), "ttl") > 1);

    // Refresh the image
    if (enable_caching) {
        self->qimage_cache = mlt_service_cache_get(MLT_PRODUCER_SERVICE(producer), "qimage.qimage");
        self->qimage = mlt_cache_item_data(self->qimage_cache, NULL);
        self->image_cache = mlt_service_cache_get(MLT_PRODUCER_SERVICE(producer), "qimage.image");
        self->current_image = mlt_cache_item_data(self->image_cache, NULL);
        self->alpha_cache = mlt_service_cache_get(MLT_PRODUCER_SERVICE(producer), "qimage.alpha");
        self->current_alpha = mlt_cache_item_data(self->alpha_cache, &self->alpha_size);
    }
    refresh_image(self, frame, *format, *width, *height, enable_caching);

    // Get width and height (may have changed during the refresh)
    *width = mlt_properties_get_int(properties, "width");
    *height = mlt_properties_get_int(properties, "height");
    *format = self->format;

    // NB: Cloning is necessary with this producer (due to processing of images ahead of use)
    // The fault is not in the design of mlt, but in the implementation of the qimage producer...
    if (self->current_image) {
        int image_size
            = mlt_image_format_size(self->format, self->current_width, self->current_height, NULL);
        if (enable_caching) {
            // Clone the image and the alpha
            uint8_t *image_copy = mlt_pool_alloc(image_size);
            memcpy(image_copy, self->current_image, image_size);
            // Now update properties so we free the copy after
            mlt_frame_set_image(frame, image_copy, image_size, mlt_pool_release);
            // We're going to pass the copy on
            *buffer = image_copy;
            mlt_log_debug(MLT_PRODUCER_SERVICE(&self->parent),
                          "%dx%d (%s)\n",
                          self->current_width,
                          self->current_height,
                          mlt_image_format_name(*format));
            // Clone the alpha channel
            if (self->current_alpha) {
                if (!self->alpha_size)
                    self->alpha_size = self->current_width * self->current_height;
                uint8_t *alpha_copy = mlt_pool_alloc(self->alpha_size);
                memcpy(alpha_copy, self->current_alpha, self->alpha_size);
                mlt_frame_set_alpha(frame, alpha_copy, self->alpha_size, mlt_pool_release);
            }
        } else {
            // For image sequences with ttl = 1 we recreate self->current_image on each frame, no need to clone
            mlt_frame_set_image(frame, self->current_image, image_size, mlt_pool_release);
            *buffer = self->current_image;
            if (self->current_alpha) {
                if (!self->alpha_size)
                    self->alpha_size = self->current_width * self->current_height;
                mlt_frame_set_alpha(frame, self->current_alpha, self->alpha_size, mlt_pool_release);
            }
        }
    } else {
        error = 1;
    }

    if (enable_caching) {
        // Release references and locks
        mlt_cache_item_close(self->qimage_cache);
        mlt_cache_item_close(self->image_cache);
        mlt_cache_item_close(self->alpha_cache);
    }
    mlt_service_unlock(MLT_PRODUCER_SERVICE(&self->parent));

    return error;
}

static int producer_get_frame(mlt_producer producer, mlt_frame_ptr frame, int index)
{
    // Get the real structure for this producer
    producer_qimage self = producer->child;

    // Fetch the producers properties
    mlt_properties producer_properties = MLT_PRODUCER_PROPERTIES(producer);

    // Cache miss
    if (!self->filenames && !self->count && mlt_properties_get(producer_properties, "resource")) {
        self->count = init_qimage(producer, mlt_properties_get(producer_properties, "resource"));
        if (!self->count) {
            return 1;
        }
        if (self->count == 1) {
            load_filenames(self, producer_properties);
        } else {
            refresh_length(producer_properties, self);
        }
    }

    // Generate a frame
    *frame = mlt_frame_init(MLT_PRODUCER_SERVICE(producer));

    if (*frame != NULL && self->count > 0) {
        // Obtain properties of frame and producer
        mlt_properties properties = MLT_FRAME_PROPERTIES(*frame);

        // Set the producer on the frame properties
        mlt_properties_set_data(properties, "producer_qimage", self, 0, NULL, NULL);

        // Update timecode on the frame we're creating
        mlt_frame_set_position(*frame, mlt_producer_position(producer));

        // Refresh the image
        if (self->count == 1 || mlt_properties_get_int(producer_properties, "ttl") > 1) {
            self->qimage_cache = mlt_service_cache_get(MLT_PRODUCER_SERVICE(producer),
                                                       "qimage.qimage");
            self->qimage = mlt_cache_item_data(self->qimage_cache, NULL);
            refresh_qimage(self, *frame, 1);
            mlt_cache_item_close(self->qimage_cache);
        }

        // Set producer-specific frame properties
        mlt_properties_set_int(properties, "progressive", 1);
        mlt_properties_set_int(properties,
                               "format",
                               mlt_properties_get_int(producer_properties, "format"));
        double force_ratio = mlt_properties_get_double(producer_properties, "force_aspect_ratio");
        if (force_ratio > 0.0)
            mlt_properties_set_double(properties, "aspect_ratio", force_ratio);
        else
            mlt_properties_set_double(properties,
                                      "aspect_ratio",
                                      mlt_properties_get_double(producer_properties,
                                                                "aspect_ratio"));

        // Push the get_image method
        mlt_frame_push_get_image(*frame, producer_get_image);
    }

    // Calculate the next timecode
    mlt_producer_prepare_next(producer);

    return 0;
}

static void producer_close(mlt_producer parent)
{
    producer_qimage self = parent->child;
    parent->close = NULL;
    mlt_service_cache_purge(MLT_PRODUCER_SERVICE(parent));
    mlt_producer_close(parent);
    mlt_properties_close(self->filenames);
    free(self);
}
