<?php
/* For licensing terms, see /license.txt */

/**
 * Image class
 * This class provides a layer to manage images
 * @author Julio Montoya <gugli100@gmail.com>
 * @package chamilo.include.image
 * @todo move in a DB configuration setting
 */
class Image
{
    public $image_wrapper = null;

    /**
     * Image constructor.
     * @param string $path
     */
    public function __construct($path)
    {
        if (IMAGE_PROCESSOR == 'gd') {
            $this->image_wrapper = new GDWrapper($path);
        } else {
            if (class_exists('Imagick')) {
                $this->image_wrapper = new ImagickWrapper($path);
            } else {
                echo Display::return_message('Class Imagick not found', 'warning');
                exit;
            }
        }
    }

    public function resize($max_size_for_picture)
    {
        $image_size = $this->get_image_size($this->image_wrapper->path);
        $width = $image_size['width'];
        $height = $image_size['height'];
        if ($width >= $height) {
            if ($width >= $max_size_for_picture) {
                // scale height
                $new_height = round($height * ($max_size_for_picture / $width));
                $this->image_wrapper->resize($max_size_for_picture, $new_height, 0);
            }
        } else { // height > $width
            if ($height >= $max_size_for_picture) {
                // scale width
                $new_width = round($width * ($max_size_for_picture / $height));
                 $this->image_wrapper->resize($new_width, $max_size_for_picture, 0);
            }
        }
    }

    public function crop($cropParameters)
    {
        $image_size = $this->get_image_size($this->image_wrapper->path);
        $src_width = $image_size['width'];
        $src_height = $image_size['height'];
        $cropParameters = explode(",", $cropParameters);
        $x = intval($cropParameters[0]);
        $y = intval($cropParameters[1]);
        $width = intval($cropParameters[2]);
        $height = intval($cropParameters[3]);

        $image = $this->image_wrapper->crop($x, $y, $width, $height, $src_width, $src_height);
        return $image;
    }

    public function send_image(
        $file = '',
        $compress = -1,
        $convert_file_to = null
    ) {
        return $this->image_wrapper->send_image(
            $file,
            $compress,
            $convert_file_to
        );
    }

    public function get_image_size()
    {
        return $this->image_wrapper->get_image_size();
    }

    public function get_image_info()
    {
        return $this->image_wrapper->get_image_info();
    }

    public function convert2bw()
    {
        $this->image_wrapper->convert2bw();
    }
}

/**
 * Image wrapper class
 *
 * @package chamilo.include.image
 */
abstract class ImageWrapper
{
    public $debug = true;
    public $path;
    public $width;
    public $height;
    public $type;
    public $allowed_extensions = array('jpeg', 'jpg', 'png', 'gif');
    public $image_validated = false;

    public function __construct($path)
    {
        if (empty($path)) {
            return false;
        }
        $this->path = $path;
        $this->set_image_wrapper(); //Creates image obj
    }

    abstract function set_image_wrapper();
    abstract function fill_image_info();
    abstract function get_image_size();
    abstract function resize($thumbw, $thumbh, $border, $specific_size = false);
    abstract function crop($x, $y, $width, $height, $src_width, $src_height);
    abstract function send_image($file = '', $compress = -1, $convert_file_to = null);

    public function get_image_info()
    {
        return array(
            'width' => $this->width,
            'height' => $this->height,
            'type' => $this->type,
        );
    }
}

/**
 * Imagick Chamilo wrapper
 *
 * @author jmontoya
 *
 * @package chamilo.include.image
 */
class ImagickWrapper extends ImageWrapper
{
    public $image;
    public $filter = Imagick::FILTER_LANCZOS;

    /**
     * ImagickWrapper constructor.
     * @param $path
     */
    public function __construct($path)
    {
          parent::__construct($path);
    }

    public function set_image_wrapper()
    {
        if ($this->debug) error_log('Image::set_image_wrapper loaded');
        try {
            if (file_exists($this->path)) {
                $this->image = new Imagick($this->path);

                if ($this->image) {
                    $this->fill_image_info(); //Fills height, width and type
                }
            } else {
                if ($this->debug) error_log('Image::image does not exist');
            }
        } catch (ImagickException $e) {
            if ($this->debug) error_log($e->getMessage());
        }
    }

    public function fill_image_info()
    {
        $image_info      = $this->image->identifyImage();

        $this->width     = $image_info['geometry']['width'];
        $this->height    = $image_info['geometry']['height'];
        $this->type      = strtolower($this->image->getImageFormat());

        if (in_array($this->type, $this->allowed_extensions)) {
            $this->image_validated = true;
            if ($this->debug) error_log('image_validated true');
        }
    }

    public function get_image_size()
    {
        $imagesize = array('width'=>0, 'height'=>0);
        if ($this->image_validated) {
            $imagesize = $this->image->getImageGeometry();
        }
        return $imagesize;
    }

    //@todo implement border logic case for Imagick
    public function resize($thumbw, $thumbh, $border, $specific_size = false)
    {
        if (!$this->image_validated) return false;

        if ($specific_size) {
            $width = $thumbw;
            $height = $thumbh;
        } else {
            $scale  = ($this->width > 0 && $this->height > 0) ? min($thumbw / $this->width, $thumbh / $this->height) : 0;
            $width  = (int) ($this->width * $scale);
            $height = (int) ($this->height * $scale);
        }
        $result = $this->image->resizeImage($width, $height, $this->filter, 1);
        $this->width  = $thumbw;
        $this->height = $thumbh;
    }

    /**
     * @author José Loguercio <jose.loguercio@beeznest.com>
     * @param int $x coordinate of the cropped region top left corner
     * @param int $y coordinate of the cropped region top left corner
     * @param int $width the width of the crop
     * @param int $height the height of the crop
     * @param int $src_width the source width of the original image
     * @param int $src_height the source height of the original image
     */
    public function crop($x, $y, $width, $height, $src_width, $src_height)
    {
        if (!$this->image_validated) {
            return false;
        }
        $this->image->cropimage($width, $height, $x, $y);
        $this->width = $width;
        $this->height = $height;
    }

    public function send_image($file = '', $compress = -1, $convert_file_to = null)
    {
        if (!$this->image_validated) {
            return false;
        }
        $type = $this->type;
        if (!empty($convert_file_to) && in_array($convert_file_to, $this->allowed_extensions)) {
            $type = $convert_file_to;
        }
        switch ($type) {
            case 'jpeg':
            case 'jpg':
                if (!$file) {
                    header("Content-type: image/jpeg");
                }
                break;
            case 'png':
                if (!$file) {
                    header("Content-type: image/png");
                }
                break;
            case 'gif':
                if (!$file) {
                    header("Content-type: image/gif");
                }
                break;
        }
        $result = false;
        try {
            $result = $this->image->writeImage($file);
        } catch (ImagickException $e) {
            if ($this->debug) {
                error_log($e->getMessage());
            }
        }

        if (!$file) {
            echo $this->image;
            $this->image->clear();
            $this->image->destroy();
        } else {
            $this->image->clear();
            $this->image->destroy();
            return $result;
        }
    }
}

/**
 * php-gd wrapper
 * @package chamilo.include.image
 */
class GDWrapper extends ImageWrapper
{
    public $bg;
    public function __construct($path)
    {
        parent::__construct($path);
    }

    public function set_image_wrapper()
    {
        $handler = null;
        $this->fill_image_info();

        switch ($this->type) {
            case 0:
                $handler = false;
                break;
            case 1:
                $handler = @imagecreatefromgif($this->path);
                $this->type = 'gif';
                break;
            case 2:
                $handler = @imagecreatefromjpeg($this->path);
                $this->type = 'jpg';
                break;
            case 3:
                $handler = @imagecreatefrompng($this->path);
                $this->type = 'png';
                break;
        }
        if ($handler) {
            $this->image_validated = true;
            $this->bg = $handler;
            @imagealphablending($this->bg, false);
            @imagesavealpha($this->bg, true);
        }
    }

    public function get_image_size()
    {
        $return_array = array('width'=>0, 'height'=>0);
        if ($this->image_validated) {
            $return_array = array('width'=>$this->width, 'height'=>$this->height);
        }
        return $return_array;
    }

    public function fill_image_info()
    {
        if (file_exists($this->path)) {
            $image_info = getimagesize($this->path);
            $this->width = $image_info[0];
            $this->height = $image_info[1];
            $this->type = $image_info[2];
        } else {
            $this->width = 0;
            $this->height = 0;
            $this->type = 0;
        }
    }

    public function resize($thumbw, $thumbh, $border, $specific_size = false)
    {
        if (!$this->image_validated) {
            return false;
        }
        if ($border == 1) {
            if ($specific_size) {
                $width = $thumbw;
                $height = $thumbh;
            } else {
                $scale = min($thumbw / $this->width, $thumbh / $this->height);
                $width = (int) ($this->width * $scale);
                $height = (int) ($this->height * $scale);
            }
            $deltaw = (int) (($thumbw - $width) / 2);
            $deltah = (int) (($thumbh - $height) / 2);
            $dst_img = @ImageCreateTrueColor($thumbw, $thumbh);
            @imagealphablending($dst_img, false);
            @imagesavealpha($dst_img, true);

            if (!empty($this->color)) {
                @imagefill($dst_img, 0, 0, $this->color);
            }
            $this->width = $thumbw;
            $this->height = $thumbh;
        } elseif ($border == 0) {
            if ($specific_size) {
                $width = $thumbw;
                $height = $thumbh;
            } else {
                $scale = ($this->width > 0 && $this->height > 0) ? min($thumbw / $this->width, $thumbh / $this->height) : 0;
                $width  = (int) ($this->width * $scale);
                $height = (int) ($this->height * $scale);
            }
            $deltaw = 0;
            $deltah = 0;
            $dst_img = @ImageCreateTrueColor($width, $height);
            @imagealphablending($dst_img, false);
            @imagesavealpha($dst_img, true);
            $this->width = $width;
            $this->height = $height;
        }
        $src_img = $this->bg;
        @ImageCopyResampled(
            $dst_img,
            $src_img,
            $deltaw,
            $deltah,
            0,
            0,
            $width,
            $height,
            ImageSX($src_img),
            ImageSY($src_img)
        );
        $this->bg = $dst_img;
        @imagedestroy($src_img);
    }

    /**
     * @author José Loguercio <jose.loguercio@beeznest.com>
     * @param int $x coordinate of the cropped region top left corner
     * @param int $y coordinate of the cropped region top left corner
     * @param int $width the width of the crop
     * @param int $height the height of the crop
     * @param int $src_width the source width of the original image
     * @param int $src_height the source height of the original image
     */
    public function crop($x, $y, $width, $height, $src_width, $src_height)
    {
        if (!$this->image_validated) {
            return false;
        }
        $this->width = $width;
        $this->height = $height;
        $src = null;
        $dest = @imagecreatetruecolor($width, $height);
        $type = $this->type;
        switch ($type) {
            case 'jpeg':
            case 'jpg':
                $src = @imagecreatefromjpeg($this->path);
                @imagecopy($dest, $src, 0, 0, $x, $y, $src_width, $src_height);
                @imagejpeg($dest, $this->path);
                break;
            case 'png':
                $src = @imagecreatefrompng($this->path);
                @imagecopy($dest, $src, 0, 0, $x, $y, $src_width, $src_height);
                @imagepng($dest, $this->path);
                break;
            case 'gif':
                $src = @imagecreatefromgif($this->path);
                @imagecopy($dest, $src, 0, 0, $x, $y, $src_width, $src_height);
                @imagegif($dest, $this->path);
                break;
            default:
                return 0;
        }
        @imagedestroy($dest);
        @imagedestroy($src);
    }

    public function send_image($file = '', $compress = -1, $convert_file_to = null)
    {
        if (!$this->image_validated) {
            return false;
        }
        $compress = (int) $compress;
        $type = $this->type;
        if (!empty($convert_file_to) && in_array($convert_file_to, $this->allowed_extensions)) {
            $type = $convert_file_to;
        }
        switch ($type) {
            case 'jpeg':
            case 'jpg':
                if (!$file) {
                    header("Content-type: image/jpeg");
                }
                if ($compress == -1) {
                    $compress = 100;
                }

                return imagejpeg($this->bg, $file, $compress);
                break;
            case 'png':
                if (!$file) {
                    header("Content-type: image/png");
                }
                if ($compress != -1) {
                    @imagetruecolortopalette($this->bg, true, $compress);
                }

                return imagepng($this->bg, $file, $compress);
                break;
            case 'gif':
                if (!$file) {
                    header("Content-type: image/gif");
                }
                if ($compress != -1) {
                    @imagetruecolortopalette($this->bg, true, $compress);
                }

                return imagegif($this->bg, $file, $compress);
                break;
            default:
                return 0;
        }
        // TODO: Occupied memory is not released, because the following fragment of code is actually dead.
        @imagedestroy($this->bg);
    }

    /**
     * Convert image to black & white
     */
    function convert2bw()
    {
        if (!$this->image_validated) {
            return false;
        }

        $dest_img = imagecreatetruecolor(imagesx($this->bg), imagesy($this->bg));
        /* copy ignore the transparent color
         * so that we can use black (0,0,0) as transparent, which is what
         * the image is filled with when created.
         */
        $transparent = imagecolorallocate($dest_img, 0, 0, 0);
        imagealphablending($dest_img, false);
        imagesavealpha($dest_img, true);
        imagecolortransparent($dest_img, $transparent);
        imagecopy($dest_img, $this->bg, 0, 0, 0, 0, imagesx($this->bg), imagesx($this->bg));
        imagefilter($dest_img, IMG_FILTER_GRAYSCALE);
        $this->bg = $dest_img;

        return true;
    }
}