<?php

namespace Icinga\Authentication;

use Icinga\Application\Logger as Logger;

class PhpSession extends Session
{
    const SESSION_NAME = "Icinga2Web";
    private $isOpen = false;
    private $isFlushed = false;
    
    private static $DEFAULT_COOKIEOPTIONS = array(
        'use_trans_sid'           => false,
        'use_cookies'             => true,
        'use_only_cooies'         => true,
        'cookie_httponly'         => true,
        'use_only_cookies'        => true,
        'hash_function'           => true,
        'hash_bits_per_character' => 5,
    );


    public function __construct(array $options = null)
    {
        if ($options !== null) {
            $options = array_merge(PhpSession::DEFAULT_COOKIEOPTIONS, $options);
        }
        foreach ($options as $sessionVar => $value) {
            if (ini_set("session.".$sessionVar, $value) === false) {
                Logger::warn(
                    "Could not set php.ini setting %s = %s. This might affect your sessions behaviour.",
                    $sessionVar,
                    $value
                );
            }
        }
    }

    private function sessionCanBeChanged()
    {
        if ($this->isFlushed) {
            Logger::error("Tried to work on a closed session, session changes will be ignored");
            return false;
        }
        return true;
    }
    
    private function sessionCanBeOpened()
    {
        if ($this->isOpen) {
            Logger::warn("Tried to open a session more than once");
            return false;
        }
        return $this->sessionCanBeChanged();
    }
 
    public function open()
    {
        if (!$this->sessionCanBeOpened()) {
            return false;
        }
            
        session_name(PhpSession::SESSION_NAME);
        session_start();
        $this->isOpen = true;
        $this->setAll($_SESSION);
        return true;
    }
  
    private function ensureOpen()
    {
        // try to open first
        if (!$this->isOpen) {
            if (!$this->open()) {
                return false;
            }
        }
        return true;
    }
 
    public function read($keepOpen = false)
    {
        if (!$this->ensureOpen) {
            return false;
        }
        if ($keepOpen) {
            return true;
        }
        $this->close();
        return true;
    }
 
    public function write($keepOpen = false)
    {
        if (!$this->ensureOpen) {
            return false;
        }
        foreach ($this->getAll() as $key => $value) {
            $_SESSION[$key] = $value;
        }
        if ($keepOpen) {
            return;
        }
        $this->close();
    }
    
    public function close()
    {
        if (!$this->isFlushed) {
            session_write_close();
        }
        $this->isFlushed = true;
    }

    public function purge()
    {
        if (!$this->ensureOpen() && !$this->isFlushed) {
            session_destroy();
        }
    }
}