_file = $file;
$this->_chunk_start = $this->getFile()->tell();
$this->_readed = 0;
$size = ($this->getFile()->getSize() - $this->_chunk_start);
if($size < 0) throw new IOException("Chunk size length is too small ($size bytes)");
$this->_chunk_size = min($size, $chunk_size);
}
/**
* @return void
*/
public function rewind():void {
$this->_readed = 0;
$this->getFile()->seek($this->_chunk_start);
}
/**
* @return int
*/
public function getSize():int {
return $this->_chunk_size;
}
/**
* @return FileStream
*/
public function getFile():FileStream {
return $this->_file;
}
/**
* @param int|false $length
*
* @return false|string
*/
public function readPiece($length=false) {
if(!$length || $length > self::CHUNK_SIZE_PIECE) $length = self::CHUNK_SIZE_PIECE;
return $this->read($length);
}
/**
* @param int $length
*
* @return int
*/
public function length(int $length):int {
if($this->_readed + $length > $this->_chunk_size) $length = $this->_chunk_size - $this->_readed;
return $length;
}
/**
* @param int $length
*
* @return false|string
*/
public function read(int $length) {
$length = $this->length($length);
if($length <= 0) return false;
$this->_readed += $length;
return $this->getFile()->read($length);
}
/**
* @return bool
*/
public function eof():bool {
return $this->getFile()->eof();
}
/**
* @param string $algorithm
*
* @return string
*/
public function getHash(string $algorithm, $binary=false):string {
$this->rewind();
$ctx = hash_init($algorithm);
while (($data = $this->read(self::CHUNK_SIZE_PIECE)) !== false) hash_update($ctx, $data);
$this->rewind();
return hash_final($ctx, $binary);
}
/**
* @return string
*/
public function __toString(): string {
return "Chunk -> " . json_encode([
'file' => $this->_file->getFile(),
'chunk_size' => $this->_chunk_size,
'chunk_start' => $this->_chunk_start,
'read' => $this->_readed,
]);
}
}