class etsis_Error
{
    /**
	 * Stores the list of errors.
	 *
	 * @since 6.1.14
	 * @var array
	 */
    public $errors = [];
    
    /**
	 * Stores the list of data for error codes.
	 *
	 * @since 6.1.14
	 * @var array
	 */
    public $error_data = [];
    
    /**
	 * Initialize the error.
	 *
	 * If `$code` is empty, the other parameters will be ignored.
	 * When `$code` is not empty, `$message` will be used even if
	 * it is empty. The `$data` parameter will be used only if it
	 * is not empty.
	 *
	 * Though the class is constructed with a single error code and
	 * message, multiple codes can be added using the `add()` method.
	 *
	 * @since 6.1.14
	 * @param string|int $code Error code
	 * @param string $message Error message
	 * @param mixed $data Optional. Error data.
	 */
    public function __construct($code = '', $message = '', $data = '')
    {
        if(empty($code)) {
            return;
        }
        
        $this->errors[$code][] = $message;
        
        if(!empty($data)) {
            $this->error_data[$code] = $data;
        }
    }
    
    /**
	 * Retrieve all error codes.
	 *
	 * @since 6.1.14
	 * @return array List of error codes, if available.
	 */
    public function get_error_codes() {
        if (empty($this->errors)) {
            return [];
        }
        
        return array_keys($this->errors);
    }
    
    /**
	 * Retrieve first error code available.
	 *
	 * @since 6.1.14
	 * @return string|int Empty string, if no error codes.
	 */
    public function get_error_code() {
        $codes = $this->get_error_codes();
        
        if(empty($codes)) {
            return '';
        }
        
        return $codes[0];
    }
    
    /**
	 * Retrieve all error messages or error messages matching code.
	 *
	 * @since 6.1.14
	 * @param string|int $code Optional. Retrieve messages matching code, if exists.
	 * @return array Error strings on success, or empty array on failure (if using code parameter).
	 */
    public function get_error_messages($code = '') {
        // Return all messages if no code specified.
        if(empty($code)) {
            $all_messages = [];
            foreach((array) $this->errors as $code => $messages) {
                $all_messages = array_merge($all_messages, $messages);
            }
            return $all_messages;
        }
        
        if(isset($this->errors[$code])) {
            return $this->errors[$code];
        } else {
            return [];
        }
    }
    
    /**
	 * Get single error message.
	 *
	 * This will get the first message available for the code. If no code is
	 * given then the first code available will be used.
	 *
	 * @since 6.1.14
	 * @param string|int $code Optional. Error code to retrieve message.
	 * @return string
	 */
    public function get_error_message($code = '') {
        if(empty($code)) {
            $code = $this->get_error_code();
        }
        $messages = $this->get_error_messages($code);
        if(empty($messages)) {
            return '';
        }
        return $messages[0];
    }
    
    /**
	 * Retrieve error data for error code.
	 *
	 * @since 6.1.14
	 * @param string|int $code Optional. Error code.
	 * @return mixed Error data, if it exists.
	 */
    public function get_error_data($code = '') {
        if(empty ($code)) {
            $code = $this->get_error_code();
        }
        if(isset($this->error_data[$code])) {
            return $this->error_data[$code];
        }
    }
    
    /**
	 * Add an error or append additional message to an existing error.
	 *
	 * @since 6.1.14
	 * @param string|int $code Error code.
	 * @param string $message Error message.
	 * @param mixed $data Optional. Error data.
	 */
    public function add($code, $message, $data = '') {
        $this->errors[$code][] = $message;
        if(!empty($data)) {
            $this->error_data[$code] = $data;
        }
    }
    
    /**
	 * Add data for error code.
	 *
	 * The error code can only contain one error data.
	 *
	 * @since 6.1.14
	 * @param mixed $data Error data.
	 * @param string|int $code Error code.
	 */
    public function add_data($data, $code = '') {
        if(empty($code)) {
            $code = $this->get_error_code();
        }
        
        $this->error_data[$code] = $data;
    }
    
    /**
	 * Removes the specified error.
	 *
	 * This function removes all error messages associated with the specified
	 * error code, along with any error data for that code.
	 *
	 * @since 6.1.14
	 * @param string|int $code Error code.
	 */
    public function remove($code) {
        unset($this->errors[$code]);
        unset($this->error_data[$code]);
    }
    
}