<?php

if (defined("MODULES_LOADED")) return;
define("MODULES_LOAD", 1);

class Module
{
	protected $name;
	protected $id;
	protected $state;
	protected $filename;
	protected $classname;
	protected $pid;
	protected $sock;
	protected $commands = array();

	const STATE_DISABLED = 0;
	const STATE_LOADING = 1;
	const STATE_LOADED = 2;
	const STATE_UNLOADING = 3;
	const STATE_UNLOADED = 4;
	const MESSAGE = 5;

	public function __construct($modulename)
	{
		log_debug("(new Module()) module name: " . var_dump($modulename));
		include VarManager::get_filename("modules");
		$this->$name = $modules[$modulename]['name'];
		$this->$id = $modulename;
		$this->$state = ($modules[$modulename]['enabled'])? Module::STATE_UNLOADED : Module::STATE_DISABLED;
		$this->$filename = $modules[$modulename]['filename'];
		$this->$classname = $modules[$modulename]['classname'];
	}

	protected function wait_answer($answer_type, &$buf)
	{
		if(is_string($answer_type)) $answer_type = array($answer_type);
		socket_set_block($this->$sock);
		$time = microtime(true);
		do
		{
			if(($answer = socket_read ($this->$sock, 1024, PHP_NORMAL_READ)) !== false)
			{
				if (trim($answer) == "") continue;
				$buf .= trim($answer) . "\n";
				
				foreach ($answer_type as $answer_type_a)
				{
					$answer_array = explode(" ", trim($answer));
					
					if ($answer_array[0] == $answer_type_a)	return $answer_array;
				}
			}
			else if (socket_last_error() == 104)
			{
				$this->$state = Module::STATE_UNLOADED;
				$buf .= "Module " . $this->getName() . " crashed.";
				throw new Exception ($buf);
			}
		} while ((microtime(true) - $time) <3);
		$buf .= "Got no " . implode(", no ", $answer_type) . " answer from module " . $this->getName() . " in the 3 seconds timeout\n";
	}	

	public function getName()
	{
		return $this->$name;
	}

	public function getState()
	{
		return $this->$state;
	}

	public function setState(int $state_num)
	{
		switch ($state_num)
		{
			case Module::STATE_DISABLED:
				break;
			case Module::STATE_LOADING:
			case Module::STATE_LOADED:
				break;
			case Module::STATE_UNLOADING:
			case Module::STATE_UNLOADED:
				break;
			default:
				return -1;
		}
	}
	
	// Creates a pair socket, then split the processes, and stock them in this class
	private function load(&$messages = NULL)
	{
		$sockets = array();
		$this->$state = STATE_LOADING;
		if (socket_create_pair(AF_UNIX, SOCK_STREAM, 0, $sockets) === false)
		{
			log_debug("Error creating socket for loading module " . $this->getName());
			$this->$state = Module::STATE_UNLOADED;
			throw new Exception("Error creating socket for loading module " . $this->getName() . ": " . socket_strerror(socket_last_error()));
		}
		$this->$sock = $sockets[1];
		$this->$pid = pcntl_fork();
		if ($this->$pid === -1)
		{
			$this->$state = Module::STATE_UNLOADED;
			throw new Exception("Failed forking child for module inclusion.");
		}
		else if ($this->$pid)
		{
			$answer = $this->wait_answer(array(Module::STATE_LOADED, Module::STATE_UNLOADED), $messages, $given_answer);
			switch ($given_answer)
			{
				case Module::STATE_LOADED:
					return $this->$state = Module::STATE_LOADED;
				case Module::STATE_UNLOADED:
					$this->$state = Module::STATE_UNLOADED;
					$msg .= "Module " . $this->getName() . " stopped.";
					throw new Exception ($msg);
			}
			return -1;
		}
		else
		{
			$this->$sock = $sockets[0];
			require (MODULES_DIR . "/" . $this->$id . "/" . $filename);
			call_user_func(array($this->$classname, 'init'));
			socket_write($this->$sock, Module::STATE_LOADED . "\n");
//			$this->listen();
		}
	}

	protected function listen()
	{
		socket_set_block($this->$sock);

	}

	public function send_command($command)
	{
		if($this->$pid == 0) return;
		socket_write($this->$sock, $command . "\n");
		socket_set_block($this->$sock);

		
	}

	private function unload()
	{
		call_user_func(array($this->$classname, 'stop'));

	}

	private function enable()
	{
	}

	private function disable()
	{
	}
}