/**
	 * @class User
	 * @author kovshenin
	 * @version 1.01
	 * For handling users data and meta
	 
	 * MySQL table structure should definately have `id` and `username`. The users meta table nees `id` chaining the users.id.
	 * Declaring can load a user. For multiple users you can use the UserSet class.
	 * Functions are to load() and loadMeta(). Parameter's either an id or the username.
	 * The user data will be put in $user->data.
	 * You can also change and save that data to the database: $user->save([param])
	 * And meta too: $user->saveMeta(); (you can use save(true) to save both)
	 */

	class User
	{
		protected $db;			// Ugh, database link
		protected $tb_users;	// The users table, duh
		protected $tb_meta;		// The users meta table, jeez
		
		protected $save_valid;		// Do we have valid user data? Used for saving and loading meta
		protected $save_meta_valid;	// Valid meta data (same as above)
		
		public $data;			// This is the data array (containing a "meta" array as the last element)
		
		function __construct($db, $query = false, $load_meta = false, $tb_users = "users", $tb_meta = "users_meta")
		{
			$this->db = $db;
			$this->tb_users = $tb_users;
			$this->tb_meta = $tb_meta;
			$this->save_valid = false;
			$this->save_meta_valid = false;
			
			if ($id) $this->load($query, $load_meta);
		}
		
		function __destruct() { }
		
		// Overloading
		public function __set($name, $value) {
	        $this->data[$name] = $value;
	    }
	
	    public function __get($name) {
	        if (array_key_exists($name, $this->data)) {
	            return $this->data[$name];
	        }
	
	        $trace = debug_backtrace();
	        trigger_error(
	            'Undefined property via __get(): ' . $name .
	            ' in ' . $trace[0]['file'] .
	            ' on line ' . $trace[0]['line'],
	            E_USER_NOTICE);
	        return null;
	 	}
		
		// I don't think there'll be much trouble here. We just load in a user (w/ or w/out meta). $query can be either a username or a user id.
		function load($query, $load_meta = false)
		{
			if (is_numeric($query))
				$sql = "SELECT * FROM `{$this->tb_users}` WHERE `id` = {$query} LIMIT 1";
			else
				$sql = "SELECT * FROM `{$this->tb_users}` WHERE `username` = {$query} LIMIT 1";
				
			$rs = mysql_query($sql, $this->db);
			if (!$rs || @mysql_num_rows($rs) == 0) return false;
			
			$this->clear();
			
			$row = mysql_fetch_assoc($rs);
			$this->data = $row;
			
			$this->save_valid = true;
			if ($load_meta) return $this->loadMeta();
			return true;
		}
		
		// Load the meta for the current user
		function loadMeta()
		{
			if ($this->save_valid)
			{
				$sql = "SELECT * FROM `{$this->tb_meta}` WHERE `id` = {$this->data["id"]} LIMIT 1";
				$rs = mysql_query($sql, $this->db);
				if (!$rs || @mysql_num_rows($rs) == 0) return false;
	
				$row = mysql_fetch_assoc($rs);
				foreach ($row as $key => $value)
					$this->data["meta_$key"] = $value;
					
				$this->save_meta_valid = true;
				
				return true;
			}
			else
				return false;
		}
		
		function save($save_meta = false)
		{
			if ($this->save_valid)
			{
				$id = $this->data["id"];
				$query = "";
				foreach($this->data as $key => $value)
				{
					if (substr($key, 0, 5) != "meta_" && $key != "id")
					{
						if (!is_numeric($value)) $value = "'{$value}'";
						$query .= "`{$key}` = {$value}, ";
					}
				}
				$query = rtrim($query, " ,");
				$sql = "UPDATE `{$this->tb_users}` SET {$query} WHERE `id` = {$id} LIMIT 1";
				$return = mysql_query($sql, $this->db);
				if ($save_meta) return $this->saveMeta();
				else return $return;
			}
			return false;
		}
		
		function saveMeta()
		{
			if ($this->save_meta_valid)
			{
				$id = $this->data["id"];
				$query = "";
				foreach($this->data as $key => $value)
				{
					if ($key != "id" && substr($key, 0,5) == "meta_")
					{
						$key = substr($key, 5);
						if (!is_numeric($value)) $value = "'{$value}'";
						$query .= "`{$key}` = {$value}, ";
					}
				}
				$query = rtrim($query, " ,");
				$sql = "UPDATE `{$this->tb_meta}` SET {$query} WHERE `id` = {$id} LIMIT 1";
				return mysql_query($sql, $this->db); 
			}
			return false;
		}
		
		function create($username, $load_meta = false)
		{
			$sql = "SELECT `id` FROM `{$this->tb_users}` WHERE `username` = '{$username}'";
			$rs = mysql_query($sql, $this->db);
			if (mysql_num_rows($rs) > 0) return false;
			
			$sql = "INSERT INTO `{$this->tb_users}` (`username`) VALUES ('$username')";
			if (!mysql_query($sql, $this->db)) return false;
			$id = mysql_insert_id($this->db);
			$sql = "INSERT INTO `{$this->tb_meta}` (`id`) VALUES ($id)";
			if (!mysql_query($sql, $this->db)) return false;
			
			return $this->load($id, $load_meta);
		}
		
		function validate()
		{
			$this->save_valid = true;
			$this->save_meta_valid = true;
		}
	
		function clear()
		{
			$this->data = array();
			$this->save_meta_valid = $this->save_valid = false;
		}
	}