visual studio - C# Uploading image to Cheverto's upload.php -

i have c# application takes screenshots , creates image files. can't seem find out how create uploading method file path passed using cheverto's upload.php. cheverto image gallery system.

here there api: https://chevereto.com/docs/api-v1

here upload.php stored on server: https://pastebin.com/bu4ejavx

<?php  namespace chv; use g, exception;  class upload { // filename => name.ext // file => /full/path/to/name.ext // name => name  public $source; public $uploaded;  // sets type of resource being uploaded public function settype($type) {     $this->type = $type; }  // set source public function setsource($source) {     $this->source = $source;     $this->type = g\is_url($this->source) ? 'url' : 'file'; }  // set destination public function setdestination($destination) {     $this->destination = g\forward_slash($destination); }  // set storage public function setstorageid($storage_id) {     $this->storage_id = is_numeric($storage_id) ? $storage_id : null; }  // set file basename public function setfilename($name) {     $this->name = $name; }  // set options public function setoptions($options) {     $this->options = $options; }  // set individual option public function setoption($key, $value) {     $this->options[$key] = $value; }  // default options public static function getdefaultoptions() {     return array(         'max_size'          => g\get_bytes('2 mb'), // should 'max_filesize'         'filenaming'        => 'original',         'exif'              => true,         'allowed_formats'   => self::getavailableimageformats(), // array     ); }  /**  * thing  * @exeption 4xx  */ public function exec() {      // merge options     $this->options = array_merge(self::getdefaultoptions(), (array) $this->options);      $this->validateinput(); // exception 1      $this->fetchsource(); // exception 2      $this->validatesourcefile(); // exception 3      if(!is_array($this->options['allowed_formats'])) {         $this->options['allowed_formats'] = explode(',', $this->options['allowed_formats']);     }      // save source name     $this->source_name = g\get_filename_without_extension($this->type == "url" ? $this->source : $this->source["name"]);      // set file extension     $this->extension = $this->source_image_fileinfo["extension"];      // workaround $name     if(!$this->name) {         $this->name = $this->source_name;     }      // fix conflicting starting dots (some apache installs)     $this->name = ltrim($this->name, '.');      // fix file extension     if(g\get_file_extension($this->name) == $this->extension) {         $this->name = g\get_filename_without_extension($this->name);     }      // set fixed filename     $this->fixed_filename = preg_replace('/(.*)\.(th|md|original|lg)\.([\w]+)$/', '$1.$3', $this->name . '.' . $this->extension);      // workaround jpeg exif data     if($this->extension == 'jpg' , array_key_exists('exif', $this->options)) {         $this->source_image_exif = null;         if($this->options['exif']) {             // fetch jpeg exif data (when available)             if(function_exists('exif_read_data')) {                 $this->source_image_exif = @exif_read_data($this->downstream);                 if($this->source_image_exif) {                     $this->source_image_exif['filename'] = $this->source_filename;                 }             }         } else {             // remove jpeg exif data             $img = imagecreatefromjpeg($this->downstream);             if($img) {                 imagejpeg($img, $this->downstream, 90);                 imagedestroy($img);             }         }     }      /*      * set uploaded_file      * local storage uploads allocated @ target destination      * external storage allocated temp directory      */     $this->uploaded_file = g\name_unique_file($this->destination, $this->options['filenaming'], $this->fixed_filename);      $this->source = [         'filename'      => $this->source_filename, // file.ext         'name'          => $this->source_name, // file         'image_exif'    => $this->source_image_exif, // exif-data array         'fileinfo'      => g\get_image_fileinfo($this->downstream), // fileinfo array     ];      // fix image orientation     if($this->source_image_exif , $this->source_image_exif["orientation"]) {         $this->fiximageorientation($this->downstream, $this->source_image_exif);     }      $uploaded = @rename($this->downstream, $this->uploaded_file);     @unlink($this->downstream);      if(file_exists($this->downstream)) {         error_log("warning: temp file " . $this->downstream . "wasn't removed.");     }      if(!$uploaded) {         throw new uploadexception("can't move temp file destination", 400);     }      // php environments     if(!$this->storage_id) {         @chmod($this->uploaded_file, 0644);     }      $this->uploaded = array(         'file'      => $this->uploaded_file,         'filename'  => g\get_filename($this->uploaded_file),         'name'      => g\get_filename_without_extension($this->uploaded_file),         'fileinfo'  => g\get_image_fileinfo($this->uploaded_file)     );  }  // available (supported) extensions public static function getavailableimageformats() {     $formats = settings::get('upload_available_image_formats');     return explode(',', $formats); }  // failover since v3.8.12 public static function getenabledimageformats() {     return image::getenabledimageformats(); }  /**  * validate_input aka "first stage validation"  * checks valid input source data  * @exception 1xx  */ protected function validateinput() {      $check_missing = ["type", "source", "destination"];     missing_values_to_exception($this, "chv\uploadexception", $check_missing, 100);      // validate $type     if(!preg_match("/^(url|file)$/", $this->type)) {         throw new uploadexception('invalid $type "'.$this->type.'"', 110);     }      // handle flood     $flood = self::handleflood();     if($flood) {         throw new uploadexception(strtr('flood detected. can upload %limit% images per %time%', ['%limit%' => $flood['limit'], '%time%' => $flood['by']]), 130);     }      // validate $source     if($this->type == 'file') {         if(count($this->source) < 5) { // valid $_files ?             throw new uploadexception("invalid file source", 120);         }     } else if($this->type == "url") {         if(!g\is_image_url($this->source) && !g\is_url($this->source)) {             throw new uploadexception("invalid image url", 122);         }     }      // validate $destination     if(!is_dir($this->destination)) { // try create missing directory          $base_dir = g\add_ending_slash(g_root_path . explode('/', preg_replace('#'.g_root_path.'#', '', $this->destination, 1))[0]);         $base_perms = fileperms($base_dir);          $old_umask = umask(0);         $make_destination = mkdir($this->destination, $base_perms, true);         chmod($this->destination, $base_perms);         umask($old_umask);          if(!$make_destination) {             throw new uploadexception('$destination '.$this->destination.' not dir', 130);         }      }      // can read $destination dir?     if(!is_readable($this->destination)) {         throw new uploadexception("can't read target destination dir", 131);     }      // can write $destination dir?     if(!is_writable($this->destination)) {         throw new uploadexception("can't write target destination dir", 132);     }      // fix $destination trailing     $this->destination = g\add_ending_slash($this->destination);  }  /**  * fetch $source file  * @exception 2xx  */ protected function fetchsource() {      // set downstream file           $this->downstream = @tempnam(sys_get_temp_dir(), 'chvtemp');      if(!$this->downstream || !@is_writable($this->downstream)) {         $this->downstream = @tempnam($this->destination, 'chvtemp');         if(!$this->downstream) {             throw new uploadexception("can't tempnam", 200);         }     }      if($this->type == 'file') {          if($this->source['error'] !== upload_err_ok) {              switch($this->source['error']) {                 case upload_err_ini_size: // 1                     throw new uploadexception('file big', 201);                 break;                 case upload_err_form_size: // 2                     throw new uploadexception('file exceeds form max size', 201);                 break;                 case upload_err_partial: // 3                     throw new uploadexception('file partially uploaded', 201);                 break;                 case upload_err_no_file: // 4                     throw new uploadexception('no file uploaded', 201);                 break;                 case upload_err_no_tmp_dir: // 5                     throw new uploadexception('missing temp folder', 201);                 break;                 case upload_err_cant_write: // 6                     throw new uploadexception('system write error', 201);                 break;                 case upload_err_extension: // 7                     throw new uploadexception('the upload stopped', 201);                 break;             }          }          if(!@rename($this->source['tmp_name'], $this->downstream)) {             throw new uploadexception("can't move temp file target upload dir", 203);         }      } else if($this->type == "url") {         try {             g\fetch_url($this->source, $this->downstream);         } catch(exception $e) {             throw new uploadexception($e->getmessage(), 202);         }     }      $this->source_filename = basename($this->type == "file" ? $this->source["name"] : $this->source);  }  protected function fiximageorientation($image_filename, $exif) {     if($exif['orientation'] == 1) return;     switch($this->extension) {         case 'jpg':             $image = imagecreatefromjpeg($image_filename);         break;     }     switch($exif['orientation']) {         case 3:             $image = imagerotate($image, 180, 0);         break;         case 6:             $image = imagerotate($image, -90, 0);         break;         case 8:             $image = imagerotate($image, 90, 0);         break;     }     imagejpeg($image, $image_filename, 90); }  /**  * validate_source_file aka "second stage validation"  * checks valid input source data  * @exception 3xx  */ protected function validatesourcefile() {      // nothing here     if(!file_exists($this->downstream)) {         throw new uploadexception("can't fetch target upload source (downstream)", 300);     }      $this->source_image_fileinfo = g\get_image_fileinfo($this->downstream);      // file info?     if(!$this->source_image_fileinfo) {         throw new uploadexception("can't target upload source info", 310);     }      // valid image fileinto?     if($this->source_image_fileinfo['width'] == '' || $this->source_image_fileinfo['height'] == '') {         throw new uploadexception("invalid image", 311);     }      // available image format?     if(!in_array($this->source_image_fileinfo['extension'], self::getavailableimageformats())) {         throw new uploadexception("unavailable image format", 313);     }      // enabled image format?     if(!in_array($this->source_image_fileinfo['extension'], $this->options['allowed_formats'])) {         throw new uploadexception(sprintf("disabled image format (%s)", $this->source_image_fileinfo['extension']), 314);     }      // mime     if(!$this->isvalidimagemime($this->source_image_fileinfo["mime"])) {         throw new uploadexception("invalid image mimetype", 312);     }      // size     if(!$this->options['max_size']) {         $this->options['max_size'] = self::getdefaultoptions()['max_size'];     }     if($this->source_image_fileinfo["size"] > $this->options["max_size"]) {         throw new uploadexception("file big - max " . g\format_bytes($this->options["max_size"]), 313);     }      // bmp?     if($this->source_image_fileinfo['extension'] == 'bmp') {         $this->imageconvert = new imageconvert($this->downstream, "png", $this->downstream);         $this->downstream = $this->imageconvert->out;         $this->source_image_fileinfo = g\get_image_fileinfo($this->downstream);     }  }  // handle flood uploads protected static function handleflood() {      $logged_user = login::getuser();      if(!getsetting('flood_uploads_protection') || $logged_user['is_admin']) {         return false;     }      $flood_limit = [];     foreach(['minute', 'hour', 'day', 'week', 'month'] $v) {         $flood_limit[$v] = getsetting('flood_uploads_' . $v);     }      try {         $db = db::getinstance();         $flood_db = $db->queryfetchsingle(         "select             count(if(image_date_gmt >= date_sub(utc_timestamp(), interval 1 minute), 1, null)) minute,             count(if(image_date_gmt >= date_sub(utc_timestamp(), interval 1 hour), 1, null)) hour,             count(if(image_date_gmt >= date_sub(utc_timestamp(), interval 1 day), 1, null)) day,             count(if(image_date_gmt >= date_sub(utc_timestamp(), interval 1 week), 1, null)) week,             count(if(image_date_gmt >= date_sub(utc_timestamp(), interval 1 month), 1, null)) month         ".db::gettable('images')." image_uploader_ip='".g\get_client_ip()."' , image_date_gmt >= date_sub(utc_timestamp(), interval 1 month)");     } catch(exception $e) {} // silence      $is_flood = false;     $flood_by = '';     foreach(['minute', 'hour', 'day', 'week', 'month'] $v) {         if($flood_limit[$v] > 0 , $flood_db[$v] >= $flood_limit[$v]) {             $flood_by = $v;             $is_flood = true;             break;         }     }      if($is_flood) {         if(getsetting('flood_uploads_notify') , !$_session['flood_uploads_notify'][$flood_by]) {             try {                 $message = strtr('flooding ip <a href="'.g\get_base_url('search/images/?q=ip:%ip').'">%ip</a>', ['%ip' => g\get_client_ip()]) . '<br>';                 if($logged_user) {                     $message .= 'user <a href="'.$logged_user['url'].'">'.$logged_user['name'].'</a><br>';                 }                 $message .= '<br>';                 $message .= '<b>uploads per time period</b>'."<br>";                 $message .= 'minute: '.$flood_db['minute']."<br>";                 $message .= 'hour: '.$flood_db['hour']."<br>";                 $message .= 'week: '.$flood_db['day']."<br>";                 $message .= 'month: '.$flood_db['week']."<br>";                 system_notification_email(['subject' => 'flood report ip '. g\get_client_ip(), 'message' => $message]);                 $_session['flood_uploads_notify'][$flood_by] = true;             } catch(exception $e) {} // silence         }          return ['flood' => true, 'limit' => $flood_limit[$flood_by], 'count' => $flood_db[$flood_by], 'by' => $flood_by];     }      return false; }  protected function isvalidimagemime($mime) {     return preg_match("@image/(gif|pjpeg|jpeg|png|x-png|bmp|x-ms-bmp|x-windows-bmp)$@", $mime); }  protected function isvalidnamingoption($string) {     return in_array($string, array("mixed", "random", "original")); } }  class uploadexception extends exception {} 

thank or guidance!