<?php
/**
 * phpBB Studio's Dice extension for the phpBB Forum Software package.
 *
 * @copyright (c) 2019 phpBB Studio <https://www.phpbbstudio.com>
 * @license GNU General Public License, version 2 (GPL-2.0)
 */

namespace phpbbstudio\dice\exception;

/**
 * phpBB Studio's Dice Base exception
 */
class base extends \Exception
{
	/**
	 * Null if the message is a string, array if the message was submitted as an array.
	 * @var string|array
	 */
	protected $message_full;

	protected $previous;

	/**
	 * Constructor.
	 *
	 * Different from normal exceptions in that we do not enforce $message to be a string.
	 *
	 * @param  string|array		$message
	 * @param  int				$code
	 * @param  \Exception		$previous
	 * @access public
	 */
	public function __construct($message = null, $code = 0, \Exception $previous = null)
	{
		parent::__construct();

		$this->message = $message;

		if (is_array($message))
		{
			$this->message = (string) $message[0];
		}

		/**
		 * We're slightly changing the way exceptions work
		 * Tools, such as xdebug, expect the message to be a string, so to prevent errors
		 * with those tools, we store our full message in message_full and only a string in message
		 */
		$this->message_full = $message;

		$this->code = $code;
		$this->previous = $previous;
	}

	/**
	 * Basic message translation for our exceptions.
	 *
	 * @param  \phpbb\language\language		$lang	Language object
	 * @return string
	 * @access public
	 */
	public function get_message(\phpbb\language\language $lang)
	{
		// Make sure our language file has been loaded
		$this->add_lang($lang);

		if (is_array($this->message_full))
		{
			return call_user_func_array([$lang, 'lang'], $this->message_full);
		}

		return $lang->lang($this->message_full);
	}

	/**
	 * Translate all portions of the message sent to the exception.
	 *
	 * Goes through each element of the array and tries to translate them
	 *
	 * @param  \phpbb\language\language		$lang				Language object
	 * @param  string|array					$message_portions	The message portions to translate
	 * @param  string|null					$parent_message		Send a string to translate all of the
	 *    														portions with the parent message (typically used to format a string
	 *    														with the given message portions). Null to ignore. Default: Null
	 * @return array|string										Array if $parent_message === null else a string
	 * @access protected
	 */
	protected function translate_portions(\phpbb\language\language $lang, $message_portions, $parent_message = null)
	{
		// Make sure our language file has been loaded
		$this->add_lang($lang);

		// Ensure we have an array
		if (!is_array($message_portions))
		{
			$message_portions = [$message_portions];
		}

		// Translate each message portion
		foreach ($message_portions as &$message)
		{
			// Attempt to translate each portion
			$translated_message = $lang->lang('EXCEPTION_' . $message);

			// Check if translating did anything
			if ($translated_message !== 'EXCEPTION_' . $message)
			{
				// It did, so replace message with the translated version
				$message = $translated_message;
			}
		}
		// Always unset a variable passed by reference in a foreach loop
		unset($message);

		if ($parent_message !== null)
		{
			// Prepend the parent message to the message portions
			array_unshift($message_portions, (string) $parent_message);

			// We return a string
			return call_user_func_array([$lang, 'lang'], $message_portions);
		}

		// We return an array
		return $message_portions;
	}

	/**
	 * Add our language file.
	 *
	 * @param  \phpbb\language\language		$lang		Language object
	 * @return void
	 * @access public
	 */
	public function add_lang(\phpbb\language\language $lang)
	{
		static $is_loaded = false;

		// We only need to load the language file once
		if ($is_loaded)
		{
			return;
		}

		// Add our language file
		$lang->add_lang('dice_exceptions', 'phpbbstudio/dice');

		// So the language file is only loaded once
		$is_loaded = true;
	}

	/**
	 * Output a string of this error message.
	 *
	 * This will hopefully be never called, always catch the expected exceptions
	 * and call get_message to translate them into an error that a user can
	 * understand
	 *
	 * @return string
	 * @access public
	 */
	public function __toString()
	{
		return is_array($this->message_full) ? (string) var_export($this->message_full, true) : (string) $this->message_full;
	}
}