<?php
/**
 * Created by PhpStorm.
 * User: Zip
 * Date: 14/12/25
 * Time: 下午4:44
 */

namespace Hood\Core\Session;

use Hood\Debug\DebugException;

class SessionNamespace
{
    protected $_namespace = "session_default";

    protected static $_namespaceLocks = array();

    protected static $_writable = false;

    public function __construct($namespace = 'session_default', $singleInstance = false)
    {
        if ($namespace === '') {
            throw new DebugException('Session Namespace 不能为空.');
        }
        if ($namespace[0] == "_") {
            throw new DebugException('Session Namespace 不能已_开头.');
        }
        $this->_namespace = $namespace;
    }

    /**
     * 锁定Session NameSpace
     */
    public function lock()
    {
        self::$_namespaceLocks[$this->_namespace] = true;
    }

    /**
     * 解锁Session NameSpace
     */
    public function unlock()
    {
        unset(self::$_namespaceLocks[$this->_namespace]);
    }

    /**
     * 解锁全部Session NameSpace
     */
    public static function unlockAll()
    {
        self::$_namespaceLocks = array();
    }

    /**
     * 检查Session NameSpace是否有锁
     * @return bool
     */
    public function isLocked()
    {
        return isset(self::$_namespaceLocks[$this->_namespace]);
    }

    /**
     * 释放所有session
     */
    public function unsetAll()
    {
        return $this->_namespaceUnset($this->_namespace);
    }

    /**
     * 释放所有session
     * @param $namespace
     * @param null $name
     */
    private function _namespaceUnset($namespace, $name = null)
    {
        $name = (string)$name;
        if ($name === '') {
            unset($_SESSION[$namespace]);
        } else {
            unset($_SESSION[$namespace][$name]);
        }
    }

    /**
     * 存入一个Session
     * @param $name
     * @param $value
     * @throws Q_Exception
     */
    public function __set($name, $value)
    {
        if (isset(self::$_namespaceLocks[$this->_namespace])) {
            throw new DebugException('This session/namespace has been marked as read-only.');
        }
        if ($name === '') {
            throw new DebugException("The '$name' key must be a non-empty string");
        }
        $name = (string)$name;
        $_SESSION[$this->_namespace][$name] = $value;
    }

    /**
     * 获取一个Session
     * @param $name
     * @return mixed
     * @throws Q_Exception
     */
    public function __get($name)
    {
        if (isset(self::$_namespaceLocks[$this->_namespace])) {
            throw new DebugException('This session/namespace has been marked as read-only.');
        }
        if ($name === '') {
            throw new DebugException("The '$name' key must be a non-empty string");
        }
        return $this->_namespaceGet($this->_namespace, $name);
    }

    /**
     * 注销session
     * @param $name
     * @throws Q_Exception
     */
    public function __unset($name)
    {
        if ($name === '') {
            throw new DebugException("The '$name' key must be a non-empty string");
        }

        return $this->_namespaceUnset($this->_namespace, $name);
    }

    /**
     * @param $namespace
     * @param null $name
     * @return mixed
     */
    private function _namespaceGet($namespace, $name = null)
    {
        if ($name === null) {
            return empty($_SESSION[$namespace]) ? NULL : $_SESSION[$namespace];
        }
        return empty($_SESSION[$namespace][$name]) ? NULL : $_SESSION[$namespace][$name];
    }

    /**
     * 判断Session是否存在
     * @param $name
     * @return bool
     * @throws Q_Exception
     */
    public function __isset($name)
    {
        if ($name === '') {
            throw new DebugException("The '$name' key must be a non-empty string");
        }
        return $this->_namespaceIsset($this->_namespace, $name);
    }

    /**
     * @param $namespace
     * @param null $name
     * @return bool
     * @throws Q_Exception
     */
    private function _namespaceIsset($namespace, $name = null)
    {
        if ($name === null) {
            return isset($_SESSION[$namespace]);
        }
        return isset($_SESSION[$namespace][$name]);
    }
}