ImageManager.php

<?php
/**
 * 2007-2015 PrestaShop
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@prestashop.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade PrestaShop to newer
 * versions in the future. If you wish to customize PrestaShop for your
 * needs please refer to http://www.prestashop.com for more information.
 *
 * @author    PrestaShop SA <contact@prestashop.com>
 * @copyright 2007-2015 PrestaShop SA
 * @license   http://opensource.org/licenses/osl-3.0.php Open Software License (OSL 3.0)
 * International Registered Trademark & Property of PrestaShop SA
 */

/**
 * This class includes functions for image manipulation
 *
 * @since 1.5.0
 */
class ImageManagerCore
{
    const ERROR_FILE_NOT_EXIST = 1;
    const ERROR_FILE_WIDTH     = 2;
    const ERROR_MEMORY_LIMIT   = 3;

    /**
     * Generate a cached thumbnail for object lists (eg. carrier, order statuses...etc)
     *
     * @param string $image Real image filename
     * @param string $cache_image Cached filename
     * @param int $size Desired size
     * @param string $image_type Image type
     * @param bool $disable_cache When turned on a timestamp will be added to the image URI to disable the HTTP cache
     * @param bool $regenerate When turned on and the file already exist, the file will be regenerated
     * @return string
     */
    public static function thumbnail($image, $cache_image, $size, $image_type = 'jpg', $disable_cache = true, $regenerate = false)
    {
        if (!file_exists($image)) {
            return '';
        }

        if (file_exists(_PS_TMP_IMG_DIR_.$cache_image) && $regenerate) {
            @unlink(_PS_TMP_IMG_DIR_.$cache_image);
        }

        if ($regenerate || !file_exists(_PS_TMP_IMG_DIR_.$cache_image)) {
            $infos = getimagesize($image);

            // Evaluate the memory required to resize the image: if it's too much, you can't resize it.
            if (!ImageManager::checkImageMemoryLimit($image)) {
                return false;
            }

            $x = $infos[0];
            $y = $infos[1];
            $max_x = $size * 3;

            // Size is already ok
            if ($y < $size && $x <= $max_x) {
                copy($image, _PS_TMP_IMG_DIR_.$cache_image);
            }
            // We need to resize */
            else {
                $ratio_x = $x / ($y / $size);
                if ($ratio_x > $max_x) {
                    $ratio_x = $max_x;
                    $size = $y / ($x / $max_x);
                }

                ImageManager::resize($image, _PS_TMP_IMG_DIR_.$cache_image, $ratio_x, $size, $image_type);
            }
        }
        // Relative link will always work, whatever the base uri set in the admin
        if (Context::getContext()->controller->controller_type == 'admin') {
            return '<img src="../img/tmp/'.$cache_image.($disable_cache ? '?time='.time() : '').'" alt="" class="imgm img-thumbnail" />';
        } else {
            return '<img src="'._PS_TMP_IMG_.$cache_image.($disable_cache ? '?time='.time() : '').'" alt="" class="imgm img-thumbnail" />';
        }
    }

    /**
     * Check if memory limit is too long or not
     *
     * @param $image
     * @return bool
     */
    public static function checkImageMemoryLimit($image)
    {
        $infos = @getimagesize($image);

        if (!is_array($infos) || !isset($infos['bits'])) {
            return true;
        }

        $memory_limit = Tools::getMemoryLimit();
        // memory_limit == -1 => unlimited memory
        if (function_exists('memory_get_usage') && (int)$memory_limit != -1) {
            $current_memory = memory_get_usage();
            $channel = isset($infos['channels']) ? ($infos['channels'] / 8) : 1;

            // Evaluate the memory required to resize the image: if it's too much, you can't resize it.
            // For perfs, avoid computing static maths formulas in the code. pow(2, 16) = 65536 ; 1024 * 1024 = 1048576
            if (($infos[0] * $infos[1] * $infos['bits'] * $channel + 65536) * 1.8 + $current_memory > $memory_limit - 1048576) {
                return false;
            }
        }

        return true;
    }

    /**
     * Resize, cut and optimize image
     *
     * @param string $src_file   Image object from $_FILE
     * @param string $dst_file   Destination filename
     * @param int    $dst_width  Desired width (optional)
     * @param int    $dst_height Desired height (optional)
     * @param string $file_type
     * @param bool   $force_type
     * @param int    $error
     * @param int    $tgt_width
     * @param int    $tgt_height
     * @param int    $quality
     * @param int    $src_width
     * @param int    $src_height
     * @return bool Operation result
     */
    public static function resize($src_file, $dst_file, $dst_width = null, $dst_height = null, $file_type = 'jpg',
                                $force_type = false, &$error = 0, &$tgt_width = null, &$tgt_height = null, $quality = 5,
                                &$src_width = null, &$src_height = null)
    {
        if (PHP_VERSION_ID < 50300) {
            clearstatcache();
        } else {
            clearstatcache(true, $src_file);
        }

        if (!file_exists($src_file) || !filesize($src_file)) {
            return !($error = self::ERROR_FILE_NOT_EXIST);
        }

        list($tmp_width, $tmp_height, $type) = getimagesize($src_file);
        $rotate = 0;
        if (function_exists('exif_read_data') && function_exists('mb_strtolower')) {
            $exif = @exif_read_data($src_file);

            if ($exif && isset($exif['Orientation'])) {
                switch ($exif['Orientation']) {
                    case 3:
                        $src_width = $tmp_width;
                        $src_height = $tmp_height;
                        $rotate = 180;
                        break;

                    case 6:
                        $src_width = $tmp_height;
                        $src_height = $tmp_width;
                        $rotate = -90;
                        break;

                    case 8:
                        $src_width = $tmp_height;
                        $src_height = $tmp_width;
                        $rotate = 90;
                        break;

                    default:
                        $src_width = $tmp_width;
                        $src_height = $tmp_height;
                }
            } else {
                $src_width = $tmp_width;
                $src_height = $tmp_height;
            }
        } else {
            $src_width = $tmp_width;
            $src_height = $tmp_height;
        }

        // If PS_IMAGE_QUALITY is activated, the generated image will be a PNG with .jpg as a file extension.
        // This allow for higher quality and for transparency. JPG source files will also benefit from a higher quality
        // because JPG reencoding by GD, even with max quality setting, degrades the image.
        if (Configuration::get('PS_IMAGE_QUALITY') == 'png_all'
            || (Configuration::get('PS_IMAGE_QUALITY') == 'png' && $type == IMAGETYPE_PNG) && !$force_type) {
            $file_type = 'png';
        }

        if (!$src_width) {
            return !($error = self::ERROR_FILE_WIDTH);
        }
        if (!$dst_width) {
            $dst_width = $src_width;
        }
        if (!$dst_height) {
            $dst_height = $src_height;
        }

        $width_diff = $dst_width / $src_width;
        $height_diff = $dst_height / $src_height;

        $ps_image_generation_method = Configuration::get('PS_IMAGE_GENERATION_METHOD');
        if ($width_diff > 1 && $height_diff > 1) {
            $next_width = $src_width;
            $next_height = $src_height;
        } else {
            if ($ps_image_generation_method == 2 || (!$ps_image_generation_method && $width_diff > $height_diff)) {
                $next_height = $dst_height;
                $next_width = round(($src_width * $next_height) / $src_height);
                $dst_width = (int)(!$ps_image_generation_method ? $dst_width : $next_width);
            } else {
                $next_width = $dst_width;
                $next_height = round($src_height * $dst_width / $src_width);
                $dst_height = (int)(!$ps_image_generation_method ? $dst_height : $next_height);
            }
        }

        if (!ImageManager::checkImageMemoryLimit($src_file)) {
            return !($error = self::ERROR_MEMORY_LIMIT);
        }

        $tgt_width  = $dst_width;
        $tgt_height = $dst_height;

        $dest_image = imagecreatetruecolor($dst_width, $dst_height);

        // If image is a PNG and the output is PNG, fill with transparency. Else fill with white background.
        if ($file_type == 'png' && $type == IMAGETYPE_PNG) {
            imagealphablending($dest_image, false);
            imagesavealpha($dest_image, true);
            $transparent = imagecolorallocatealpha($dest_image, 255, 255, 255, 127);
            imagefilledrectangle($dest_image, 0, 0, $dst_width, $dst_height, $transparent);
        } else {
            $white = imagecolorallocate($dest_image, 255, 255, 255);
            imagefilledrectangle($dest_image, 0, 0, $dst_width, $dst_height, $white);
        }

        $src_image = ImageManager::create($type, $src_file);
        if ($rotate) {
            $src_image = imagerotate($src_image, $rotate, 0);
        }

        if ($dst_width >= $src_width && $dst_height >= $src_height) {
            imagecopyresized($dest_image, $src_image, (int)(($dst_width - $next_width) / 2), (int)(($dst_height - $next_height) / 2), 0, 0, $next_width, $next_height, $src_width, $src_height);
        } else {
            ImageManager::imagecopyresampled($dest_image, $src_image, (int)(($dst_width - $next_width) / 2), (int)(($dst_height - $next_height) / 2), 0, 0, $next_width, $next_height, $src_width, $src_height, $quality);
        }
        $write_file = ImageManager::write($file_type, $dest_image, $dst_file);
        @imagedestroy($src_image);
        return $write_file;
    }

    public static function imagecopyresampled(&$dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h, $quality = 3)
    {
        // Plug-and-Play fastimagecopyresampled function replaces much slower imagecopyresampled.
        // Just include this function and change all "imagecopyresampled" references to "fastimagecopyresampled".
        // Typically from 30 to 60 times faster when reducing high resolution images down to thumbnail size using the default quality setting.
        // Author: Tim Eckel - Date: 09/07/07 - Version: 1.1 - Project: FreeRingers.net - Freely distributable - These comments must remain.
        //
        // Optional "quality" parameter (defaults is 3). Fractional values are allowed, for example 1.5. Must be greater than zero.
        // Between 0 and 1 = Fast, but mosaic results, closer to 0 increases the mosaic effect.
        // 1 = Up to 350 times faster. Poor results, looks very similar to imagecopyresized.
        // 2 = Up to 95 times faster.  Images appear a little sharp, some prefer this over a quality of 3.
        // 3 = Up to 60 times faster.  Will give high quality smooth results very close to imagecopyresampled, just faster.
        // 4 = Up to 25 times faster.  Almost identical to imagecopyresampled for most images.
        // 5 = No speedup. Just uses imagecopyresampled, no advantage over imagecopyresampled.

        if (empty($src_image) || empty($dst_image) || $quality <= 0) {
            return false;
        }
        if ($quality < 5 && (($dst_w * $quality) < $src_w || ($dst_h * $quality) < $src_h)) {
            $temp = imagecreatetruecolor($dst_w * $quality + 1, $dst_h * $quality + 1);
            imagecopyresized($temp, $src_image, 0, 0, $src_x, $src_y, $dst_w * $quality + 1, $dst_h * $quality + 1, $src_w, $src_h);
            imagecopyresampled($dst_image, $temp, $dst_x, $dst_y, 0, 0, $dst_w, $dst_h, $dst_w * $quality, $dst_h * $quality);
            imagedestroy($temp);
        } else {
            imagecopyresampled($dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);
        }
        return true;
    }

    /**
     * Check if file is a real image
     *
     * @param string $filename File path to check
     * @param string $file_mime_type File known mime type (generally from $_FILES)
     * @param array $mime_type_list Allowed MIME types
     * @return bool
     */
    public static function isRealImage($filename, $file_mime_type = null, $mime_type_list = null)
    {
        // Detect mime content type
        $mime_type = false;
        if (!$mime_type_list) {
            $mime_type_list = array('image/gif', 'image/jpg', 'image/jpeg', 'image/pjpeg', 'image/png', 'image/x-png');
        }

        // Try 4 different methods to determine the mime type
        if (function_exists('getimagesize')) {
            $image_info = @getimagesize($filename);

            if ($image_info) {
                $mime_type = $image_info['mime'];
            } else {
                $file_mime_type = false;
            }
        } elseif (function_exists('finfo_open')) {
            $const = defined('FILEINFO_MIME_TYPE') ? FILEINFO_MIME_TYPE : FILEINFO_MIME;
            $finfo = finfo_open($const);
            $mime_type = finfo_file($finfo, $filename);
            finfo_close($finfo);
        } elseif (function_exists('mime_content_type')) {
            $mime_type = mime_content_type($filename);
        } elseif (function_exists('exec')) {
            $mime_type = trim(exec('file -b --mime-type '.escapeshellarg($filename)));
            if (!$mime_type) {
                $mime_type = trim(exec('file --mime '.escapeshellarg($filename)));
            }
            if (!$mime_type) {
                $mime_type = trim(exec('file -bi '.escapeshellarg($filename)));
            }
        }

        if ($file_mime_type && (empty($mime_type) || $mime_type == 'regular file' || $mime_type == 'text/plain')) {
            $mime_type = $file_mime_type;
        }

        // For each allowed MIME type, we are looking for it inside the current MIME type
        foreach ($mime_type_list as $type) {
            if (strstr($mime_type, $type)) {
                return true;
            }
        }

        return false;
    }

    /**
     * Check if image file extension is correct
     *
     * @param string $filename Real filename
     * @param array|null $authorized_extensions
     * @return bool True if it's correct
     */
    public static function isCorrectImageFileExt($filename, $authorized_extensions = null)
    {
        // Filter on file extension
        if ($authorized_extensions === null) {
            $authorized_extensions = array('gif', 'jpg', 'jpeg', 'jpe', 'png');
        }
        $name_explode = explode('.', $filename);
        if (count($name_explode) >= 2) {
            $current_extension = strtolower($name_explode[count($name_explode) - 1]);
            if (!in_array($current_extension, $authorized_extensions)) {
                return false;
            }
        } else {
            return false;
        }

        return true;
    }

    /**
     * Validate image upload (check image type and weight)
     *
     * @param array $file Upload $_FILE value
     * @param int $max_file_size Maximum upload size
     * @return bool|string Return false if no error encountered
     */
    public static function validateUpload($file, $max_file_size = 0, $types = null)
    {
        if ((int)$max_file_size > 0 && $file['size'] > (int)$max_file_size) {
            return sprintf(Tools::displayError('Image is too large (%1$d kB). Maximum allowed: %2$d kB'), $file['size'] / 1024, $max_file_size / 1024);
        }
        if (!ImageManager::isRealImage($file['tmp_name'], $file['type']) || !ImageManager::isCorrectImageFileExt($file['name'], $types) || preg_match('/\%00/', $file['name'])) {
            return Tools::displayError('Image format not recognized, allowed formats are: .gif, .jpg, .png');
        }
        if ($file['error']) {
            return sprintf(Tools::displayError('Error while uploading image; please change your server\'s settings. (Error code: %s)'), $file['error']);
        }
        return false;
    }

    /**
     * Validate icon upload
     *
     * @param array $file Upload $_FILE value
     * @param int $max_file_size Maximum upload size
     * @return bool|string Return false if no error encountered
     */
    public static function validateIconUpload($file, $max_file_size = 0)
    {
        if ((int)$max_file_size > 0 && $file['size'] > $max_file_size) {
            return sprintf(
                Tools::displayError('Image is too large (%1$d kB). Maximum allowed: %2$d kB'),
                $file['size'] / 1000,
                $max_file_size / 1000
            );
        }
        if (substr($file['name'], -4) != '.ico') {
            return Tools::displayError('Image format not recognized, allowed formats are: .ico');
        }
        if ($file['error']) {
            return Tools::displayError('Error while uploading image; please change your server\'s settings.');
        }
        return false;
    }

    /**
     * Cut image
     *
     * @param array $src_file Origin filename
     * @param string $dst_file Destination filename
     * @param int $dst_width Desired width
     * @param int $dst_height Desired height
     * @param string $file_type
     * @param int $dst_x
     * @param int $dst_y
     *
     * @return bool Operation result
     */
    public static function cut($src_file, $dst_file, $dst_width = null, $dst_height = null, $file_type = 'jpg', $dst_x = 0, $dst_y = 0)
    {
        if (!file_exists($src_file)) {
            return false;
        }

        // Source information
        $src_info = getimagesize($src_file);
        $src = array(
            'width' => $src_info[0],
            'height' => $src_info[1],
            'ressource' => ImageManager::create($src_info[2], $src_file),
        );

        // Destination information
        $dest = array();
        $dest['x'] = $dst_x;
        $dest['y'] = $dst_y;
        $dest['width'] = !is_null($dst_width) ? $dst_width : $src['width'];
        $dest['height'] = !is_null($dst_height) ? $dst_height : $src['height'];
        $dest['ressource'] = ImageManager::createWhiteImage($dest['width'], $dest['height']);

        $white = imagecolorallocate($dest['ressource'], 255, 255, 255);
        imagecopyresampled($dest['ressource'], $src['ressource'], 0, 0, $dest['x'], $dest['y'], $dest['width'], $dest['height'], $dest['width'], $dest['height']);
        imagecolortransparent($dest['ressource'], $white);
        $return = ImageManager::write($file_type, $dest['ressource'], $dst_file);
        @imagedestroy($src['ressource']);
        return    $return;
    }

    /**
     * Create an image with GD extension from a given type
     *
     * @param string $type
     * @param string $filename
     * @return resource
     */
    public static function create($type, $filename)
    {
        switch ($type) {
            case IMAGETYPE_GIF :
                return imagecreatefromgif($filename);
            break;

            case IMAGETYPE_PNG :
                return imagecreatefrompng($filename);
            break;

            case IMAGETYPE_JPEG :
            default:
                return imagecreatefromjpeg($filename);
            break;
        }
    }

    /**
     * Create an empty image with white background
     *
     * @param int $width
     * @param int $height
     * @return resource
     */
    public static function createWhiteImage($width, $height)
    {
        $image = imagecreatetruecolor($width, $height);
        $white = imagecolorallocate($image, 255, 255, 255);
        imagefill($image, 0, 0, $white);
        return $image;
    }

    /**
     * Generate and write image
     *
     * @param string $type
     * @param resource $resource
     * @param string $filename
     * @return bool
     */
    public static function write($type, $resource, $filename)
    {
        static $ps_png_quality = null;
        static $ps_jpeg_quality = null;

        if ($ps_png_quality === null) {
            $ps_png_quality = Configuration::get('PS_PNG_QUALITY');
        }

        if ($ps_jpeg_quality === null) {
            $ps_jpeg_quality = Configuration::get('PS_JPEG_QUALITY');
        }

        switch ($type) {
            case 'gif':
                $success = imagegif($resource, $filename);
            break;

            case 'png':
                $quality = ($ps_png_quality === false ? 7 : $ps_png_quality);
                $success = imagepng($resource, $filename, (int)$quality);
            break;

            case 'jpg':
            case 'jpeg':
            default:
                $quality = ($ps_jpeg_quality === false ? 90 : $ps_jpeg_quality);
                imageinterlace($resource, 1); /// make it PROGRESSIVE
                $success = imagejpeg($resource, $filename, (int)$quality);
            break;
        }
        imagedestroy($resource);
        @chmod($filename, 0664);
        return $success;
    }

    /**
     * Return the mime type by the file extension
     *
     * @param string $file_name
     * @return string
     */
    public static function getMimeTypeByExtension($file_name)
    {
        $types = array(
                        'image/gif' => array('gif'),
                        'image/jpeg' => array('jpg', 'jpeg'),
                        'image/png' => array('png')
                    );
        $extension = substr($file_name, strrpos($file_name, '.') + 1);

        $mime_type = null;
        foreach ($types as $mime => $exts) {
            if (in_array($extension, $exts)) {
                $mime_type = $mime;
                break;
            }
        }

        if ($mime_type === null) {
            $mime_type = 'image/jpeg';
        }

        return $mime_type;
    }
}