<?php
/*
 * Name: Handle ICO
 * Author: Shish <webmaster@shishnet.org>
 * Description: Handle windows icons
 */

class IcoFileHandler extends Extension
{
    public function onDataUpload(DataUploadEvent $event)
    {
        if ($this->supported_ext($event->type) && $this->check_contents($event->tmpname)) {
            $hash = $event->hash;
            $ha = substr($hash, 0, 2);
            move_upload_to_archive($event);
            send_event(new ThumbnailGenerationEvent($event->hash, $event->type));
            $image = $this->create_image_from_data("images/$ha/$hash", $event->metadata);
            if (is_null($image)) {
                throw new UploadException("Icon handler failed to create image object from data");
            }
            $iae = new ImageAdditionEvent($image);
            send_event($iae);
            $event->image_id = $iae->image->id;
        }
    }

    public function onThumbnailGeneration(ThumbnailGenerationEvent $event)
    {
        if ($this->supported_ext($event->type)) {
            $this->create_thumb($event->hash);
        }
    }

    public function onDisplayingImage(DisplayingImageEvent $event)
    {
        global $page;
        if ($this->supported_ext($event->image->ext)) {
            $this->theme->display_image($page, $event->image);
        }
    }

    private function supported_ext(string $ext): bool
    {
        $exts = ["ico", "ani", "cur"];
        return in_array(strtolower($ext), $exts);
    }

    private function create_image_from_data(string $filename, array $metadata)
    {
        $image = new Image();

        $fp = fopen($filename, "r");
        $header = unpack("Snull/Stype/Scount", fread($fp, 6));

        $subheader = unpack("Cwidth/Cheight/Ccolours/Cnull/Splanes/Sbpp/Lsize/loffset", fread($fp, 16));
        fclose($fp);

        $width = $subheader['width'];
        $height = $subheader['height'];
        $image->width = $width == 0 ? 256 : $width;
        $image->height = $height == 0 ? 256 : $height;

        $image->filesize  = $metadata['size'];
        $image->hash      = $metadata['hash'];
        $image->filename  = $metadata['filename'];
        $image->ext       = $metadata['extension'];
        $image->tag_array = is_array($metadata['tags']) ? $metadata['tags'] : Tag::explode($metadata['tags']);
        $image->source    = $metadata['source'];

        return $image;
    }

    private function check_contents(string $file): bool
    {
        if (!file_exists($file)) {
            return false;
        }
        $fp = fopen($file, "r");
        $header = unpack("Snull/Stype/Scount", fread($fp, 6));
        fclose($fp);
        return ($header['null'] == 0 && ($header['type'] == 0 || $header['type'] == 1));
    }

    private function create_thumb(string $hash): bool
    {
        global $config;

        $inname  = warehouse_path("images", $hash);
        $outname = warehouse_path("thumbs", $hash);

        $w = $config->get_int("thumb_width");
        $h = $config->get_int("thumb_height");
        $q = $config->get_int("thumb_quality");
        $mem = $config->get_int("thumb_mem_limit") / 1024 / 1024; // IM takes memory in MB

        if ($config->get_bool("ico_convert")) {
            // "-limit memory $mem" broken?
            exec("convert {$inname}[0] -geometry {$w}x{$h} -quality {$q} jpg:$outname");
        } else {
            copy($inname, $outname);
        }

        return true;
    }
}