<?php

/**
 * MessageSource_SQLite class 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>
 * @package Prado\I18N\core
 */

namespace Prado\I18N\core;

/**
 * Get the MessageSource class file.
 */
require_once(dirname(__FILE__).'/MessageSource.php');

/**
 * Get the I18N utility file, contains the DSN parser.
 */
require_once(dirname(__FILE__).'/util.php');

/**
 * MessageSource_SQLite class.
 * 
 * Retrive the message translation from a SQLite database.
 *
 * See the MessageSource::factory() method to instantiate this class.
 *
 * @author Xiang Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @package Prado\I18N\core
 */
class MessageSource_SQLite extends MessageSource
{
	/**
	 * The SQLite datasource, the filename of the database.
	 * @var string 
	 */
	protected $source;
	
	/**
	 * Constructor.
	 * Create a new message source using SQLite.
	 * @see MessageSource::factory();
	 * @param string SQLite datasource, in PEAR's DB DSN format.
	 */
	function __construct($source)
	{
		$dsn = parseDSN((string)$source);
		$this->source = $dsn['database'];
	}
	
	/**
	 * Get an array of messages for a particular catalogue and cultural 
	 * variant.
	 * @param string the catalogue name + variant
	 * @return array translation messages.
	 */
	protected function &loadData($variant)
	{
		$variant = sqlite_escape_string($variant);
		
		$statement = 
			"SELECT t.id, t.source, t.target, t.comments
				FROM trans_unit t, catalogue c
 				WHERE c.cat_id =  t.cat_id
					AND c.name = '{$variant}' 
				ORDER BY id ASC";
	
		$db = sqlite_open($this->source);
		$rs = sqlite_query($statement, $db);
			
		$result = array();
		
		while($row = sqlite_fetch_array($rs,SQLITE_NUM))
		{
			$source = $row[1];
			$result[$source][] = $row[2]; //target
			$result[$source][] = $row[0]; //id
			$result[$source][] = $row[3]; //comments
		}

		sqlite_close($db);
		
		return $result;
	}
	
	/**
	 * Get the last modified unix-time for this particular catalogue+variant.
	 * We need to query the database to get the date_modified.
	 * @param string catalogue+variant
	 * @return int last modified in unix-time format.
	 */	
	protected function getLastModified($source)
	{
		$source = sqlite_escape_string($source);

		$db = sqlite_open($this->source);
		
		$rs = sqlite_query(
			"SELECT date_modified FROM catalogue WHERE name = '{$source}'",
			$db);
			
		$result = $rs ? (int)sqlite_fetch_single($rs) : 0;
		
		sqlite_close($db);		
	
		return $result;			
	}
	
	/**
	 * Check if a particular catalogue+variant exists in the database.
	 * @param string catalogue+variant
	 * @return boolean true if the catalogue+variant is in the database, 
	 * false otherwise.
	 */
	protected function isValidSource($variant)
	{
		$variant = sqlite_escape_string($variant);
		$db = sqlite_open($this->source);
		$rs = sqlite_query(
			"SELECT COUNT(*) FROM catalogue WHERE name = '{$variant}'",
			$db);
		$result = $rs && (int)sqlite_fetch_single($rs);	
		sqlite_close($db);

		return $result;
	}
	
	/**
	 * Get all the variants of a particular catalogue.
	 * @param string catalogue name
	 * @return array list of all variants for this catalogue. 
	 */
	protected function getCatalogueList($catalogue)
	{
		$variants = explode('_',$this->culture);
		
		$catalogues = array($catalogue);

		$variant = null;
				
		for($i = 0, $k = count($variants); $i < $k; ++$i)
		{						
			if(isset($variants[$i]{0}))
			{
				$variant .= ($variant)?'_'.$variants[$i]:$variants[$i];
				$catalogues[] = $catalogue.'.'.$variant;
			}
		}
		return array_reverse($catalogues);	
	}
	
	/**
	 * Retrive catalogue details, array($cat_id, $variant, $count).
	 * @param string catalogue
	 * @return array catalogue details, array($cat_id, $variant, $count). 
	 */
	private function getCatalogueDetails($catalogue='messages')
	{
		if(empty($catalogue))
			$catalogue = 'messages';

		$variant = $catalogue.'.'.$this->culture;
		
		$name = sqlite_escape_string($this->getSource($variant));	
			
		$db = sqlite_open($this->source);
		
		$rs = sqlite_query("SELECT cat_id
					FROM catalogue WHERE name = '{$name}'", $db);
		
		if(sqlite_num_rows($rs) != 1)
			return false;
		
		$cat_id = (int)sqlite_fetch_single($rs);
		
		//first get the catalogue ID
		$rs = sqlite_query(
			"SELECT count(msg_id)
				FROM trans_unit
				WHERE cat_id = {$cat_id}", $db);

		$count = (int)sqlite_fetch_single($rs);

		sqlite_close($db);	
		
		return array($cat_id, $variant, $count);
	}
	
	/**
	 * Update the catalogue last modified time.
	 * @return boolean true if updated, false otherwise. 
	 */
	private function updateCatalogueTime($cat_id, $variant, $db)
	{
		$time = time();
		
		$result = sqlite_query("UPDATE catalogue 
							SET date_modified = {$time}
							WHERE cat_id = {$cat_id}", $db);

		if(!empty($this->cache))		
			$this->cache->clean($variant, $this->culture);	
		
		return $result;
	}
		
	/**
	 * 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 the catalogue to add to
	 * @return boolean true if saved successfuly, false otherwise.
	 */
	function save($catalogue='messages')
	{
		$messages = $this->untranslated;
		
		if(count($messages) <= 0) return false;				
		
		$details = $this->getCatalogueDetails($catalogue);	
		
		if($details)
			list($cat_id, $variant, $count) = $details;
		else
			return false;
		
		if($cat_id <= 0) return false;
		$inserted = 0;
		
		$db = sqlite_open($this->source);
		$time = time();

		foreach($messages as $message)
		{
			$message = sqlite_escape_string($message);
			$statement = "INSERT INTO trans_unit
				(cat_id,id,source,date_added) VALUES
				({$cat_id}, {$count},'{$message}',$time)";
			if(sqlite_query($statement, $db))
			{
				$count++; $inserted++;			
			}
		}
		if($inserted > 0)
			$this->updateCatalogueTime($cat_id, $variant, $db);
	
		sqlite_close($db);	
		
		return $inserted > 0;		
	}	
		
	/**
	 * Update the translation.
	 * @param string the source string.
	 * @param string the new translation string.
	 * @param string comments
	 * @param string the catalogue of the translation.
	 * @return boolean true if translation was updated, false otherwise. 
	 */	
	function update($text, $target, $comments, $catalogue='messages')
	{
		$details = $this->getCatalogueDetails($catalogue);
		if($details)
			list($cat_id, $variant, $count) = $details;
		else
			return false;
		
		$comments = sqlite_escape_string($comments);
		$target = sqlite_escape_string($target);
		$text = sqlite_escape_string($text);
		
		$time = time();
		
		$db = sqlite_open($this->source);
		
		$statement = "UPDATE trans_unit SET
						target = '{$target}',
						comments = '{$comments}',
						date_modified = '{$time}'
					WHERE cat_id = {$cat_id} 
						AND source = '{$text}'";
		
		$updated = false;
		
		if(sqlite_query($statement, $db))
			$updated = $this->updateCatalogueTime($cat_id, $variant, $db);
		
		sqlite_close($db);			
				
		return $updated;
	}	
	
	/**
	 * Delete a particular message from the specified catalogue.
	 * @param string the source message to delete.
	 * @param string the catalogue to delete from.
	 * @return boolean true if deleted, false otherwise. 
	 */
	function delete($message, $catalogue='messages')
	{
		$details = $this->getCatalogueDetails($catalogue);
		if($details)
			list($cat_id, $variant, $count) = $details;
		else
			return false;
			
		$db = sqlite_open($this->source);
		$text = sqlite_escape_string($message);
		
		$statement = "DELETE FROM trans_unit WHERE
						cat_id = {$cat_id} AND source = '{$message}'";
		$deleted = false;
				
		if(sqlite_query($statement, $db))
			$deleted = $this->updateCatalogueTime($cat_id, $variant, $db);		
			
		sqlite_close($db);	
				
		return $deleted;
	}	
	
	/**
	 * Returns a list of catalogue as key and all it variants as value.
	 * @return array list of catalogues 
	 */
	function catalogues()
	{
		$db = sqlite_open($this->source);
		$statement = 'SELECT name FROM catalogue ORDER BY name';
		$rs = sqlite_query($statement, $db);
		$result = array();
		while($row = sqlite_fetch_array($rs,SQLITE_NUM))
		{
			$details = explode('.',$row[0]);
			if(!isset($details[1])) $details[1] = null;
			
			$result[] = $details;
		}
		sqlite_close($db);
		return $result;
	}	
}