class BinaryData

class BinaryData extends PrimitiveBase implements BinaryInterface {
    
    /**
     * The file resource URI.
     *
     * @var string
     */
    protected $uri;
    
    /**
     * A generic file resource handle.
     *
     * @var resource
     */
    public $handle = NULL;
    
    /**
     * {@inheritdoc}
     */
    public function getValue() {
        // If the value has been set by (absolute) stream resource URI, access the
        // resource now.
        if (!isset($this->handle) && isset($this->uri)) {
            $this->handle = is_readable($this->uri) ? fopen($this->uri, 'rb') : FALSE;
        }
        return $this->handle;
    }
    
    /**
     * Overrides TypedData::setValue().
     *
     * Supports a PHP file resource or an (absolute) stream resource URI as value.
     */
    public function setValue($value, $notify = TRUE) {
        if (!isset($value)) {
            $this->handle = NULL;
            $this->uri = NULL;
        }
        elseif (is_string($value)) {
            // Note: For performance reasons we store the given URI and access the
            // resource upon request. See BinaryData::getValue()
            $this->uri = $value;
            $this->handle = NULL;
        }
        else {
            $this->handle = $value;
        }
        // Notify the parent of any changes.
        if ($notify && isset($this->parent)) {
            $this->parent
                ->onChange($this->name);
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function getString() {
        // Return the file content.
        $contents = '';
        while (!feof($this->getValue())) {
            $contents .= fread($this->handle, 8192);
        }
        return $contents;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getCastedValue() {
        return $this->getValue();
    }

}