<?php
    $user = $_POST['username'];
    $password = $_POST['password'];
    $assignment = $_POST['assignment'];

    $true = chk_user($user, $password) && ($user == "rkala" || $user == "icm2014501" || $user == "pis2016001");

    if(!$true) {
        die("Login Failed");
    }

    $assignment_dir = "codes/Assignment-".$assignment;
    $target_dir = $assignment_dir;
    $uploadOk = 1;
    
    $dir = $target_dir;
    $zip_file = 'zips/Assignment-'.$assignment.'.zip';

    // Get real path for our folder
    $rootPath = realpath($dir);

    // Initialize archive object
    $zip = new ZipArchive();
    $zip->open($zip_file, ZipArchive::CREATE | ZipArchive::OVERWRITE);

    // Create recursive directory iterator
    /** @var SplFileInfo[] $files */
    $files = new RecursiveIteratorIterator(
        new RecursiveDirectoryIterator($rootPath),
        RecursiveIteratorIterator::LEAVES_ONLY
    );

    foreach ($files as $name => $file)
    {
        // Skip directories (they would be added automatically)
        if (!$file->isDir())
        {
            // Get real and relative path for current file
            $filePath = $file->getRealPath();
            $relativePath = substr($filePath, strlen($rootPath) + 1);

            // Add current file to archive
            $zip->addFile($filePath, $relativePath);
        }
    }

    // Zip archive will be created only after closing object
    $zip->close();


    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename='.basename($zip_file));
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($zip_file));
    readfile($zip_file);

    function chk_user( $uid, $pwd ) {
        if ($pwd) {
            $ds = ldap_connect("172.31.1.41");
            ldap_set_option($ds, LDAP_OPT_PROTOCOL_VERSION, 3);
            $a = ldap_search($ds, "dc=iiita,dc=ac,dc=in", "uid=".$uid );
            $b = ldap_get_entries( $ds, $a );
            $dn = $b[0]["dn"];
            $ldapbind=@ldap_bind($ds, $dn, $pwd);
            if ($ldapbind) {
                return 1;
            } else {
                return 0;
            }
            ldap_close($ds);
        } else {
            return 0;
        }
    }    
?>