<?php

use Sabre\DAV;
use Sabre\DAV\Auth;
use Sabre\DAV\Server;
use Sabre\DAV\Exception\Forbidden;
	
// The autoloader
require 'vendor/autoload.php';

$pdo = new \PDO('sqlite:/var/webuzo/db/webdisk.db');

// Throwing exceptions when PDO comes across an error:
$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);

// Creating the backend.
$authBackend = new Sabre\DAV\Auth\Backend\BasicCallBack(function($username, $password){
	
	//file_put_contents('/tmp/webdisk', $username.' - '.$password."\n", FILE_APPEND);
	
	// check the username and password here, and then just return true or false
	$pdo = $GLOBALS['pdo'];

	// Throwing exceptions when PDO comes across an error:
	$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
	
	$res = $pdo->query("SELECT * FROM users WHERE username = :username");
	$res->execute(['username' => $username]);
	
	$verify = false;
	
	if(!empty($res)){
		$user = $res->fetch();
		$verify = password_verify($password, $user['password']);
	}
	
	// If verification is successful
	if(!empty($verify) && !empty($_SERVER['PHP_AUTH_USER'])){
		
		$username = $_SERVER['PHP_AUTH_USER'];

		$res = $pdo->query("SELECT * FROM users WHERE username = :username");
		$res->execute(['username' => $username]);

		if(!empty($res)){
			$user = $res->fetch();
			$path = $user['homedir'];
		}
		
		$u = posix_getpwnam($user['owner']);
		posix_setgid($u['gid']);
		posix_setuid($u['uid']);
		
	}
	
	//$rootDirectory = new DAV\FS\Directory($path);
	//$GLOBALS['server']->tree = new Tree($rootDirectory);
	
	return $verify;
	
});

class SabreServerPlugin extends \Sabre\DAV\ServerPlugin{
	
	public const BEFORE_CREATE_FILE = 'beforeCreateFile';
	public const BEFORE_FILE_UPDATE = 'beforeWriteContent';
	public const BEFORE_CREATION_DUE_TO_UPDATE = 'beforeBind';
	public const BEFORE_DELETION_DUE_TO_UPDATE = 'beforeUnbind';
	public const BEFORE_LOCK = 'beforeLock';
	public const BEFORE_UNLOCK = 'beforeUnlock';
	public const BEFORE_PROPERTY_REQUEST = 'propFind';

	private Server $server;
	private Security $security;

	public function __construct(){
		// Do nothing
	}

	public function initialize(Server $server): void
	{
		$this->server = $server;
		$this->server->on(self::BEFORE_CREATE_FILE, [$this, 'beforeCreateFile']);
		$this->server->on(self::BEFORE_FILE_UPDATE, [$this, 'beforeFileUpdate']);
		$this->server->on(self::BEFORE_CREATION_DUE_TO_UPDATE, [$this, 'beforeCreationDueToUpdate']);
		$this->server->on(self::BEFORE_DELETION_DUE_TO_UPDATE, [$this, 'beforeDeletionDueToUpdate']);
		$this->server->on(self::BEFORE_LOCK, [$this, 'beforeLock']);
		$this->server->on(self::BEFORE_UNLOCK, [$this, 'beforeUnlock']);
		//$this->server->on(self::BEFORE_PROPERTY_REQUEST, [$this, 'beforePropertyRequest']);
	}

	public function beforeCreateFile(string $path, &$data, \Sabre\DAV\ICollection $parent, &$modified): void
	{
		throw new Forbidden();
	}

	public function beforeFileUpdate($path, \Sabre\DAV\IFile $node, &$data, &$modified): void
	{
		throw new Forbidden();
	}

	public function beforeCreationDueToUpdate($path): bool
	{
		throw new Forbidden();
		return true;
	}

	public function beforeDeletionDueToUpdate($path): bool
	{
		throw new Forbidden();
		return true;
	}

	public function beforeLock($path, \Sabre\DAV\Locks\LockInfo $lock): bool
	{
		throw new Forbidden();
		return true;
	}

	public function beforeUnlock($path, \Sabre\DAV\Locks\LockInfo $lock): bool
	{
		throw new Forbidden();
		return true;
	}

	public function beforePropertyRequest(\Sabre\DAV\PropFind $propfind, \Sabre\Dav\INode $node): void
	{
		throw new Forbidden();
	}
}

// Creating the plugin
$authPlugin = new Auth\Plugin($authBackend);

$path = '/var/webuzo-data/webdisk';

if(!empty($_SERVER['PHP_AUTH_USER'])){
		
	$username = $_SERVER['PHP_AUTH_USER'];

	$res = $pdo->query("SELECT * FROM users WHERE username = :username");
	$res->execute(['username' => $username]);

	if(!empty($res)){
		$user = $res->fetch();
		$path = $user['homedir'];
	}
	
	$u = posix_getpwnam($user['owner']);
	posix_setgid($u['gid']);
	posix_setuid($u['uid']);
	
}

// Are we still root ?
if(posix_getuid() == 0){
	$u = posix_getpwnam('nobody');
	posix_setgid($u['gid']);
	posix_setuid($u['uid']);
}

$rootDirectory = new DAV\FS\Directory($path);

// The server object is responsible for making sense out of the WebDAV protocol
$server = new DAV\Server($rootDirectory);

// If your server is not on your webroot, make sure the following line has the
// correct information
$server->setBaseUri('/');

$locksBackend = new Sabre\DAV\Locks\Backend\PDO($pdo);

// Add the plugin to the server.
$locksPlugin = new Sabre\DAV\Locks\Plugin($locksBackend);
$server->addPlugin($locksPlugin);

$server->addPlugin($authPlugin);

// This ensures that we get a pretty index in the browser, but it is
// optional.
//$server->addPlugin(new DAV\Browser\Plugin());

// Restrict writes if not allowed !
if(!empty($user) && !empty($user['permissions']) && !preg_match('/w/is', $user['permissions'])){
	$server->addPlugin(new SabreServerPlugin());
}

// All we need to do now, is to fire up the server
$server->exec();