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<?php
/**
 * autoResizeOnUpload
 * 
 * Description: Automatically resizes images uploaded through the MODX File Manager
 * if they exceed the dimensions specified in the config settings below and the
 * file extension is included in the upload_images System Setting.
 * 
 * Provides basic filename sanitization.
 * 
 * How it works: plugin is called on each OnFileManagerUpload event.  if multiple files are uploaded simultaneously the plugin is called for each file.
 * 
 * Dependancies: Resizer Extra (http://modx.com/extras/package/resizer)
 * 
 * Configuration: set plugin to fire on system event: OnFileManagerUpload
 *                adjust variables in Settings section below to suit your requirements.
 * 
 * Credit: Inspired by the work of Vasiliy Naumkin <bezumkin@yandex.ru> (https://bezumkin.ru/sections/components/118/)
 * Credit: Forum posts by Bruno (http://forums.modx.com/u/Bruno17)
 * Credit: Forum posts by LuK (http://forums.modx.com/u/exside)
 * Author: Chris Dempsey
 * 
 * 
 */

if ( !isset( $modx ) ) return;

if( $modx->Event->name != 'OnFileManagerUpload' )  {
    return;
}

/**
 * Settings
 * 
 * Adjust as required.
 * Disable logging in production environment otherwise MODX error log will fill up with
 * unnecessary entries.
 * 
 */

// logging
$logging = false;            // perform logging both in MODX and Resizer debug

// config to pass to Resizer which supports a subset of phpThumb options (https://github.com/oo12/Resizer#options)
$config = array ( 
    'w'     =>  1600,       // max width
    'h'     =>  1600,       // max height
    'zc'    =>  0,          // zoom crop 
    'bg'    =>  '#FFF',     // backgroud, only required if zc = 0 
    'q'     =>  78,         // quality 
    'scale' =>  1           // scale
);

/*********************************
 * No need to edit below this line
 ********************************/
 
 
 
 
 
 
$file = $modx->event->params[ 'files' ][ 'file' ]; 

// abort on error
if ( $file['error']  !=  0 )  {
    $modx->log( modX::LOG_LEVEL_ERROR, 'autoResizeOnUpload: $file["error"] occured.' );
    return;
}

$directory_uploaded_to = $modx->event->params [ 'directory' ];      // get upload directory from OnFileManagerUpload event
$file_name = $file[ 'name' ];                                       // get the filename eg. picture.jpg

/**
 * sanitize file_name
 */
 
// replace non alphanumeric characters with dash
$file_name_safe = preg_replace( '/[^a-zA-Z0-9-_\.]/','-', $file_name );

// file_name could end up with consecutive dashes for replaced characters eg.
// image (2014).jpg becomes: image--2014-.jpg so remove consecutive dashes
$file_name_safe = preg_replace( '/--+/', '-', $file_name_safe );

// create array of upload_images extensions from system settings
$allowed_extensions = explode ( ',' , $modx->getOption ( 'upload_images' ) );

// trim white space
$allowed_extensions = array_map('trim', $allowed_extensions);

/**
 * Get media source properties for default media source
 * 
 */

// get id of default_media_source
$default_media_source   = $modx->getOption('default_media_source');

// get modMediaSource object using default_media_source id
$obj_media_source       = $modx->getObject( 'modMediaSource', array( 'id' => $default_media_source ) );

// get modMediaSource properties
$ms_props               = $obj_media_source->get( 'properties' );
$ms_basePath            = $ms_props[ 'basePath' ][ 'value' ];

$file_path_abs  = MODX_BASE_PATH . $ms_basePath . $directory_uploaded_to . $file_name;

$file_path_abs_safe  = MODX_BASE_PATH . $ms_basePath . $directory_uploaded_to . $file_name_safe;

// extension of uploaded file
$file_ext       = substr ( strrchr( $file_name,  '.' ),  1 );

// get properties of image as array, includes file type and a height/width text string
$file_dimensions = getimagesize ( $file_path_abs );

/**
 * Final check before running Resizer
 * 
 * Is image filetype is in allowed extensions +
 * are dimensions of uploaded file greater than sizes allowed in config
 * 
 */
if  ( (in_array ($file_ext, $allowed_extensions) ) && ( ($file_dimensions[0] > $config['w'] || $file_dimensions[1] > $config['h']) ) ) {

    // example code source for resizer: https://github.com/oo12/Resizer#snippet-developers
    //$modx->loadClass( 'Resizer', MODX_CORE_PATH . 'components/resizer/model/', true, true );
    
    if (!$modx->loadClass( 'Resizer', MODX_CORE_PATH . 'components/resizer/model/', true, true )) {
        // Resizer not installed, log error and exit
        $modx->log(modX::LOG_LEVEL_ERROR, 'Error: autoResizeOnUpload Plugin - Resizer component not found.');
        return;
    }
    
    $resizer = new Resizer( $modx );  // pass in the modx object
   
    if ( $logging == true ) {
        $resizer->debug = true;  // (optional) Enable debugging messages.
    }
    
    $resizer->processImage(
        $file_path_abs,         // input image file (path can be absolute or relative to MODX_BASE_PATH)
        $file_path_abs_safe,    // output image file. Extension determines image format.
        $config                 // config array
    );
    
    // now have a copy of the uploaded file with safe name, delete the original image file but only if
    // the filename does not match the original, otherwise we'll delete the resized image.
    
    if( $file_path_abs !== $file_path_abs_safe ) {
    
        if ( !unlink( $file_path_abs ) ) {
            if ( $logging == true ) {
                $log_resizer .= 'Delete original file: failed.' . PHP_EOL;
            }
        } else {
            if ( $logging == true ) {
                $log_resizer .= 'Delete original file: success.' . PHP_EOL;
            }
        }

    }
    
    
    // (optional) record Resizer debug message array for the modx error log
    if ( $logging == true ) {
        $log_resizer .= PHP_EOL . '=======[ Resizer Log ]=======' . PHP_EOL;
        $log_resizer .= substr(print_r($resizer->debugmessages, TRUE), 7, -2);
    }

}

/**
 * Debug logging
 */
 
if ( $logging == true ) {
    $log_autoResizeOnUpload .= PHP_EOL . '=======[ autoResizeOnUpload Plugin - Debug Log ]=======' . PHP_EOL;
    
    // OnFileManagerUpload fired
    $log_autoResizeOnUpload .= 'OnFileManagerUpload event fired.' . PHP_EOL;
    
    // ms_basePath
    $log_autoResizeOnUpload .= '$ms_basePath = ' . $ms_basePath . PHP_EOL;
    
    // file
    $log_autoResizeOnUpload .= '$file = ' . $file . PHP_EOL;
    
    // directory_uploaded_to
    $log_autoResizeOnUpload .= '$directory_uploaded_to = ' . $directory_uploaded_to . PHP_EOL;
    
    // file_path_abs
    $log_autoResizeOnUpload .= '$file_path_abs = ' . $file_path_abs . PHP_EOL;
    
    // file_path_abs_safe
    $log_autoResizeOnUpload .= '$file_path_abs_safe = ' . $file_path_abs_safe . PHP_EOL;
    
    // file_name
    $log_autoResizeOnUpload .= '$file_name = ' . $file_name . PHP_EOL;

    // file_ext
    $log_autoResizeOnUpload .= '$file_ext = ' . $file_ext . PHP_EOL;
    
    // file_dimensions
    $log_autoResizeOnUpload .= '$file_dimensions = ' . $file_dimensions . PHP_EOL;
    
    // width of uploaded file
    $log_autoResizeOnUpload .= 'WIDTH = ' . $file_dimensions[0] . PHP_EOL;
    
    // heght of uploaded file
    $log_autoResizeOnUpload .= 'HEIGHT = ' . $file_dimensions[1] . PHP_EOL;
    
    // resizer log
    $log_autoResizeOnUpload .= PHP_EOL . '$resizer_log: ' . PHP_EOL . $log_resizer;
    
    // commit details to MODX error log
    $modx->log( modX::LOG_LEVEL_ERROR, $log_autoResizeOnUpload );
}

<?php
/**
 * ResizeOnUpload Plugin
 *
 * Events: OnFileManagerUpload
 * Author: Vasiliy Naumkin <bezumkin@yandex.ru>
 * Required: PhpThumbOf snippet for resizing images
 */

if ($modx->event->name != 'OnFileManagerUpload') {return;}

/* Settings */
$config = array(
    '/' => array(           // default config
        'w' => 800          // max width of uploaded images
        ,'h' => 600         // max height of uploaded images
        ,'zc' => 0          // zoom & crop
        ,'bg' => '#fff'     // backgroud, needed only for zc=0
        ,'q' => 100         // quality
    )
    //,'/assets/images/' => array()
);

/*----------*/
$file = $modx->event->params['files']['file'];
$directory = $modx->event->params['directory'];
if ($file['error'] != 0) {return;}

$name = $file['name'];
$extensions = explode(',', $modx->getOption('upload_images'));

if (array_key_exists($directory, $config)) {
	$config = $config[$directory];
}
else {
	$config = $config['/'];
}

$filename = MODX_BASE_PATH . $directory . $name;
$ext = substr(strrchr($name, '.'), 1);
if (in_array($ext, $extensions)) {
	$sizes = getimagesize($filename);
	$format = substr($sizes['mime'],6);
	if ($sizes[0] > $config['w'] || $sizes[1] > $config['h']) {
		if ($sizes[0] < $config['w']) {$config['w'] = $sizes[0];}
		if ($sizes[1] < $config['h']) {$config['h'] = $sizes[1];}
		
		$options = '';
		foreach ($config as $k => $v) {
			$options .= '&'.$k.'='.$v;
		}
		$resized = $modx->runSnippet('PhpThumbOf', array(
			'input' => $directory.$name
			,'options' => $options
		));
		rename(MODX_BASE_PATH . substr($resized, 1), $filename);
	}
}

// source: https://bezumkin.ru/sections/components/118/