<?php

// disable timeout for large sites.
set_time_limit(0);

/**
	Elgg 1.0
 */
function file_matrix_1_0($username)
{
	$matrix = "";
	
	$len = strlen($username);
	if ($len > 5)
		$len = 5;
	
	for ($n = 0; $n < $len; $n++) {
		if (ctype_alnum($username[$n]))
			$matrix .= $username[$n] . "/";
	}	

	return $matrix.$username."/";
}


/**
	Elgg 1.1, 1.2 and 1.5
 */
function file_matrix_1_1($filename)
{
	$matrix = "";
	
	$name = $filename;
	$filename = mb_str_split($filename);
	if (!$filename) return false;
	
	$len = count($filename);
	if ($len > 5)
		$len = 5;
	
	for ($n = 0; $n < $len; $n++) {
		$matrix .= $filename[$n] . "/";
	}	

	return $matrix.$name."/";
}

function mb_str_split($string, $charset = 'UTF8')
{
	if (is_callable('mb_substr'))
	{
		$length = mb_strlen($string);
		$array = array();
		
		while ($length)
		{
			$array[] = mb_substr($string, 0, 1, $charset);
			$string = mb_substr($string, 1, $length, $charset);
			
			$length = mb_strlen($string);
		}
		
		return $array;
	}
	else
		return str_split($string);
	
	return false;
}


/**
	Elgg 1.6
 */
function file_matrix_1_6($filename)
{
	$invalid_fs_chars = '*\'\\/"!$%^&*.%(){}[]#~?<>;|¬`@-+=';
	
	$matrix = "";
	
	$name = $filename;
	$filename = mb_str_split($filename);
	if (!$filename) return false;
	
	$len = count($filename);
	if ($len > 5)
		$len = 5;
	
	for ($n = 0; $n < $len; $n++) {
		
		// Prevent a matrix being formed with unsafe characters
		$char = $filename[$n];
		if (strpos($invalid_fs_chars, $char)!==false)
			$char = '_';
		
		$matrix .= $char . "/";
	}	

	return $matrix.$name."/";
}


/**
 * Scans a directory and moves any files from $from to $to 
 * preserving structure and handling existing paths.
 * Will no overwrite files in $to.
 *
 * TRAILING SLASHES REQUIRED.
 *
 * @param $from From dir.
 * @param $to To dir.
 * @param $move Bool. True to move, false to copy.
 * @param $preference str to|from If file collisions, which dir has preference.
 */
function merge_directories($from, $to, $move=false, $preference='to') {
	if (!$entries = scandir($from)) {
		return false;
	}
	
	// character filtering needs to be elsewhere.
	if (!is_dir($to)) {
		mkdir($to, 0700, true);
	}
	
	if ($move === true) {
		$f = 'rename';
	} else {
		$f = 'copy';
	}
	
	foreach ($entries as $entry) {
		if ($entry == '.' || $entry == '..') {
			continue;
		}
		
		$from_path = $from . $entry;
		$to_path = $to . $entry;
		
		// check to see if the path exists and is a dir, if so, recurse.
		if (is_dir($from_path) && is_dir($to_path)) {
			$from_path .= '/';
			$to_path .= '/';
			merge_directories($from_path, $to_path, $move, $preference);
			
			// since it's a dir that already exists we don't need to move it
			continue;
		}
		
		// only move if target doesn't exist or if preference is for the from dir
		if (!file_exists($to_path) || $preference == 'from') {
			
			if ($f($from_path, $to_path)) {
				//elgg_dump("Moved/Copied $from_path to $to_path");
			}
		} else {
			//elgg_dump("Ignoring $from_path -> $to_path");
		}
	}
}

function user_file_matrix($guid) {
	// lookup the entity
	$user = get_entity($guid);
	if ($user->type != 'user')
	{
		// only to be used for user directories
		return FALSE;
	}
	
	if (!$user->time_created) {
		// fall back to deprecated method
		return $this->deprecated_file_matrix($user->username);
	}
	
	$time_created = date('Y/m/d', $user->time_created);
	return "$time_created/$user->guid/";
}

global $DB_QUERY_CACHE, $DB_PROFILE, $ENTITY_CACHE;
/**
	Upgrade file locations
 */
$users = mysql_query("SELECT guid, username FROM {$CONFIG->dbprefix}users_entity WHERE username != ''");
while ($user = mysql_fetch_object($users)) {
	$DB_QUERY_CACHE = $DB_PROFILE = $ENTITY_CACHE = array();

	$to = $CONFIG->dataroot . user_file_matrix($user->guid);
	foreach (array('1_0', '1_1', '1_6') as $version) {
		$function = "file_matrix_$version";
		$from = $CONFIG->dataroot . $function($user->username);
		merge_directories($from, $to, $move=TRUE, $preference='from');
	}
}
