<?php

/**
 * IMessageSource interface file.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the BSD License.
 *
 * Copyright(c) 2004 by Qiang Xue. All rights reserved.
 *
 * To contact the author write to {@link mailto:qiang.xue@gmail.com Qiang Xue}
 * The latest version of PRADO can be obtained from:
 * {@link http://prado.sourceforge.net/}
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 */

namespace Prado\I18N\core;

/**
 * IMessageSource interface.
 *
 * All messages source used by MessageFormat must be of IMessageSource.
 * It defines a set of operations to add and retrive messages from the
 * message source. In addition, message source can load a particular
 * catalogue.
 *
 * @author Xiang Wei Zhuo <weizhuo[at]gmail[dot]com>
 */
interface IMessageSource
{
	/**
	 * Load the translation table for this particular catalogue.
	 * The translation should be loaded in the following order.
	 *  # [1] call getCatalogeList($catalogue) to get a list of
	 *    variants for for the specified $catalogue.
	 *  # [2] for each of the variants, call getSource($variant)
	 *    to get the resource, could be a file or catalogue ID.
	 *  # [3] verify that this resource is valid by calling isValidSource($source)
	 *  # [4] try to get the messages from the cache
	 *  # [5] if a cache miss, call load($source) to load the message array
	 *  # [6] store the messages to cache.
	 *  # [7] continue with the foreach loop, e.g. goto [2].
	 *
	 * @param string $catalogue a catalogue to load
	 * @return bool true if loaded, false otherwise.
	 */
	public function load($catalogue = 'messages');

	/**
	 * Get the translation table. This includes all the loaded sections.
	 * It must return a 2 level array of translation strings.
	 * # "catalogue+variant" the catalogue and its variants.
	 * # "source string" translation keys, and its translations.
	 * <code>
	 *   array('catalogue+variant' =>
	 *       array('source string' => 'target string', ...)
	 *             ...),
	 *        ...);
	 * </code>
	 *
	 * @return array 2 level array translation table.
	 */
	public function read();

	/**
	 * Save the list of untranslated blocks to the translation source.
	 * If the translation was not found, you should add those
	 * strings to the translation source via the <b>append()</b> method.
	 * @param string $catalogue the catalogue to add to
	 * @return bool true if saved successfuly, false otherwise.
	 */
	public function save($catalogue = 'messages');

	/**
	 * Add a untranslated message to the source. Need to call save()
	 * to save the messages to source.
	 * @param string $message message to add
	 */
	public function append($message);

	/**
	 * Delete a particular message from the specified catalogue.
	 * @param string $message the source message to delete.
	 * @param string $catalogue the catalogue to delete from.
	 * @return bool true if deleted, false otherwise.
	 */
	public function delete($message, $catalogue = 'messages');

	/**
	 * Update the translation.
	 * @param string $text the source string.
	 * @param string $target the new translation string.
	 * @param string $comments comments
	 * @param string $catalogue the catalogue of the translation.
	 * @return bool true if translation was updated, false otherwise.
	 */
	public function update($text, $target, $comments, $catalogue = 'messages');

	/**
	 * Returns a list of catalogue as key and all it variants as value.
	 * @return array list of catalogues
	 */
	public function catalogues();

	/**
	 * Set the culture for this particular message source.
	 * @param string $culture the Culture name.
	 */
	public function setCulture($culture);

	/**
	 * Get the culture identifier for the source.
	 * @return string culture identifier.
	 */
	public function getCulture();
}