<?php


set_time_limit(0);
error_reporting(E_ERROR);

$FTP_HOST = '0.0.0.0';
$FTP_PORT = 2121;
$FTP_USER = 'root';
$FTP_PASS = 'Mjoshanitcm7717';
$FTP_ROOT = realpath(__DIR__ . '/../storage/app/public');

$envFile = __DIR__ . '/../.env';
if (file_exists($envFile)) {
    foreach (file($envFile) as $line) {
        $line = trim($line);
        if (strpos($line, '=') === false || strpos($line, '#') === 0) continue;
        [$key, $val] = explode('=', $line, 2);
        $key = trim($key); $val = trim($val, "\" \t\n\r");
        if ($key === 'FTP_PORT')  $FTP_PORT = (int)$val;
        if ($key === 'FTP_USER')  $FTP_USER = $val;
        if ($key === 'FTP_PASS')  $FTP_PASS = $val;
        if ($key === 'FTP_ROOT')  $FTP_ROOT = $val;
    }
}

if (!$FTP_ROOT || !is_dir($FTP_ROOT)) {
    die("ERROR: Root dir not found: {$FTP_ROOT}\n");
}

$server = @stream_socket_server("tcp://{$FTP_HOST}:{$FTP_PORT}", $errno, $errstr);
if (!$server) {
    die("ERROR: Cannot start FTP server on port {$FTP_PORT}: {$errstr}\n"
      . "Hint: Run as Administrator or change FTP_PORT in .env\n");
}

echo "=========================================\n";
echo "  matab-panel FTP Server\n";
echo "=========================================\n";
echo "Port : {$FTP_PORT}\n";
echo "User : {$FTP_USER}\n";
echo "Root : {$FTP_ROOT}\n";
echo "Press Ctrl+C to stop\n\n";

while ($ctrl = stream_socket_accept($server, -1)) {
    $peer = stream_socket_get_name($ctrl, true);
    echo "[" . date('H:i:s') . "] Connected: {$peer}\n";
    try {
        ftpSession($ctrl, $FTP_USER, $FTP_PASS, $FTP_ROOT);
    } catch (\Throwable $e) {
        echo "Error: " . $e->getMessage() . "\n";
    }
    fclose($ctrl);
    echo "[" . date('H:i:s') . "] Disconnected: {$peer}\n";
}
fclose($server);


function ftpSend($ctrl, string $msg): void
{
    fwrite($ctrl, $msg . "\r\n");
}

function ftpRead($ctrl): string
{
    $line = fgets($ctrl, 8192);
    return $line ? rtrim($line, "\r\n") : '';
}

function ftpOpenData(&$pasvSock): mixed
{
    if (!$pasvSock) return null;
    stream_set_timeout($pasvSock, 15);
    $data = stream_socket_accept($pasvSock, 15);
    fclose($pasvSock);
    $pasvSock = null;
    return $data ?: null;
}

function ftpResolvePath(string $cwd, string $arg, string $root): ?string
{
    if ($arg === '') {
        $path = $cwd;
    } elseif ($arg[0] === '/') {
        $path = $arg;
    } else {
        $path = rtrim($cwd, '/') . '/' . $arg;
    }
    // Normalize
    $parts = explode('/', $path);
    $out = [];
    foreach ($parts as $p) {
        if ($p === '' || $p === '.') continue;
        if ($p === '..') { array_pop($out); } else { $out[] = $p; }
    }
    $path = '/' . implode('/', $out);
    $real = realpath($root . $path);
    if ($real !== false && strpos($real, realpath($root)) !== 0) return null;
    return $path;
}

function ftpSession($ctrl, string $user, string $pass, string $root): void
{
    $cwd      = '/';
    $authed   = false;
    $pendUser = '';
    $pasvSock = null;

    stream_set_timeout($ctrl, 300); 
    ftpSend($ctrl, '220 matab-panel FTP Server');

    while (!feof($ctrl)) {
        $line = ftpRead($ctrl);
        if ($line === '') {
            $info = stream_get_meta_data($ctrl);
            if ($info['timed_out']) continue;
            break; 
        }

        $parts = explode(' ', $line, 2);
        $cmd   = strtoupper($parts[0]);
        $arg   = isset($parts[1]) ? trim($parts[1]) : '';

        switch ($cmd) {

            case 'USER':
                $pendUser = $arg;
                ftpSend($ctrl, '331 Password required');
                break;

            case 'PASS':
                if ($pendUser === $user && $arg === $pass) {
                    $authed = true;
                    ftpSend($ctrl, '230 Login successful');
                    echo "  Auth OK\n";
                } else {
                    ftpSend($ctrl, '530 Login incorrect');
                }
                break;

            case 'SYST':
                ftpSend($ctrl, '215 UNIX Type: L8');
                break;

            case 'FEAT':
                ftpSend($ctrl, "211-Features:\r\n PASV\r\n211 End");
                break;

            case 'TYPE':
                ftpSend($ctrl, '200 Type set to ' . ($arg ?: 'I'));
                break;

            case 'PWD': case 'XPWD':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                ftpSend($ctrl, '257 "' . $cwd . '"');
                break;

            case 'CWD': case 'XCWD':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $p = ftpResolvePath($cwd, $arg, $root);
                if ($p !== null && is_dir($root . $p)) {
                    $cwd = $p;
                    ftpSend($ctrl, '250 OK');
                } else {
                    ftpSend($ctrl, '550 No such directory');
                }
                break;

            case 'CDUP':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $cwd = dirname($cwd) ?: '/';
                ftpSend($ctrl, '200 OK');
                break;

            case 'MKD': case 'XMKD':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $p = ftpResolvePath($cwd, $arg, $root);
                if ($p !== null) {
                    $full = $root . $p;
                    if (!is_dir($full)) mkdir($full, 0755, true);
                    ftpSend($ctrl, '257 "' . $p . '" created');
                } else {
                    ftpSend($ctrl, '550 Failed');
                }
                break;

            case 'PASV':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                if ($pasvSock) fclose($pasvSock);
                $pasvPort = rand(60000, 60020); // fixed range — must match firewall rule
                $pasvSock = @stream_socket_server("tcp://0.0.0.0:{$pasvPort}", $e1, $e2);
                if (!$pasvSock) { ftpSend($ctrl, '425 Cannot open passive connection'); break; }
                $localAddr = stream_socket_get_name($ctrl, false);
                $localIp   = explode(':', $localAddr)[0];
                $p1 = intdiv($pasvPort, 256);
                $p2 = $pasvPort % 256;
                ftpSend($ctrl, '227 Entering Passive Mode (' . str_replace('.', ',', $localIp) . ",{$p1},{$p2})");
                break;

            case 'LIST': case 'NLST':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $data = ftpOpenData($pasvSock);
                if (!$data) { ftpSend($ctrl, '425 No data connection'); break; }
                ftpSend($ctrl, '150 Opening data connection');
                $dirPath = $root . $cwd;
                $list    = '';
                if (is_dir($dirPath)) {
                    foreach (scandir($dirPath) as $f) {
                        if ($f === '.' || $f === '..') continue;
                        $fp   = $dirPath . '/' . $f;
                        $size = is_file($fp) ? filesize($fp) : 0;
                        $type = is_dir($fp) ? 'd' : '-';
                        $list .= "{$type}rw-r--r-- 1 root root {$size} Jan  1 00:00 {$f}\r\n";
                    }
                }
                fwrite($data, $list);
                fclose($data);
                ftpSend($ctrl, '226 Transfer complete');
                break;

            case 'STOR':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $p = ftpResolvePath($cwd, $arg, $root);
                if ($p === null) { ftpSend($ctrl, '550 Invalid path'); break; }
                $full = $root . $p;
                $dir  = dirname($full);
                if (!is_dir($dir)) mkdir($dir, 0755, true);
                $fp = @fopen($full, 'wb');
                if (!$fp) { ftpSend($ctrl, '550 Cannot write file'); break; }
                $data = ftpOpenData($pasvSock);
                if (!$data) { fclose($fp); ftpSend($ctrl, '425 No data connection'); break; }
                ftpSend($ctrl, '150 Ready to receive');
                stream_set_timeout($data, 30);
                stream_copy_to_stream($data, $fp);
                fclose($fp);
                fclose($data);
                echo "  STOR: {$p} (" . number_format(filesize($full)) . " bytes)\n";
                ftpSend($ctrl, '226 Transfer complete');
                break;

            case 'RETR':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $p = ftpResolvePath($cwd, $arg, $root);
                if ($p === null || !file_exists($root . $p)) { ftpSend($ctrl, '550 File not found'); break; }
                $data = ftpOpenData($pasvSock);
                if (!$data) { ftpSend($ctrl, '425 No data connection'); break; }
                ftpSend($ctrl, '150 Opening data connection');
                $fp = fopen($root . $p, 'rb');
                while (!feof($fp)) {
                    $buf = fread($fp, 65536);
                    if ($buf !== false && $buf !== '') fwrite($data, $buf);
                }
                fclose($fp);
                fclose($data);
                echo "  RETR: {$p}\n";
                ftpSend($ctrl, '226 Transfer complete');
                break;

            case 'SIZE':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                $p = ftpResolvePath($cwd, $arg, $root);
                if ($p !== null && file_exists($root . $p)) {
                    ftpSend($ctrl, '213 ' . filesize($root . $p));
                } else {
                    ftpSend($ctrl, '550 File not found');
                }
                break;

            case 'OPTS':
                ftpSend($ctrl, '200 OK');
                break;

            case 'PBSZ':
                ftpSend($ctrl, '200 PBSZ=0');
                break;

            case 'PROT':
                ftpSend($ctrl, '200 Protection level set to ' . ($arg ?: 'C'));
                break;

            case 'EPSV':
                if (!$authed) { ftpSend($ctrl, '530 Not logged in'); break; }
                if ($pasvSock) fclose($pasvSock);
                $pasvPort = rand(60000, 60020);
                $pasvSock = @stream_socket_server("tcp://0.0.0.0:{$pasvPort}", $e1, $e2);
                if (!$pasvSock) { ftpSend($ctrl, '425 Cannot open passive connection'); break; }
                ftpSend($ctrl, "229 Entering Extended Passive Mode (|||{$pasvPort}|)");
                break;

            case 'EPRT':
                ftpSend($ctrl, '200 OK');
                break;

            case 'NOOP':
                ftpSend($ctrl, '200 OK');
                break;

            case 'QUIT':
                ftpSend($ctrl, '221 Goodbye');
                return;

            default:
                echo "  [UNKNOWN CMD] {$cmd} {$arg}\n";
                ftpSend($ctrl, '502 Not implemented: ' . $cmd);
        }
    }
}