Paper Server Manager [Auto-updating, auto-restarting] (CMD)

@echo off
rem ---  CONFIG  ---

set Version=1.16.1
set AutoUpdate=TRUE
set ListVersions=FALSE
set AutoRestart=TRUE
set MaxRam=4096M
set MinRam=4096M
set JavaExe=java
set "ExtraArgs=nogui"

rem NOTE: If you do not have cURL installed, set AutoUpdate to FALSE.
rem       You can check if you have it installed by opening cmd and
rem       typing curl and pressing enter.



rem ---  DO NOT EDIT BELOW UNLESS YOU KNOW WHAT YOU ARE DOING!  ---

title Paper Server Manager
if /I %ListVersions%==TRUE (
  for /f "tokens=*" %%a in ('curl -s https://papermc.io/api/v1/paper') do set URL=%%a
  echo [BATCH] Supported Versions: %URL:~31,-2%
  echo [BATCH] Press any key to exit.
  pause >nul
  exit /B
)
set LEN=0
:LOOP
for /f "tokens=*" %%a in ('echo %%Version:~^%LEN%') do set CUT=%%a%%
for /f "tokens=*" %%a in ('echo %CUT%') do set CUT=%%a
if not "%CUT%"=="ECHO is on." set /A LEN+=1 && goto :LOOP
set /A "CUT=52+%LEN%"
if /I %AutoUpdate%==TRUE (
  echo [BATCH] Checking for updates...
  for /f "tokens=*" %%a in ('curl -s https://papermc.io/api/v1/paper/%Version%') do set URL=%%a
  for /f "tokens=*" %%a in ('echo %%URL:~^%CUT%') do set LEN=%%a%%
  for /f "tokens=1,* delims=," %%a in ('echo %LEN%') do set URL=%%a
  If exist Paper-%Version%-%URL:~0,-1%.jar (
    echo [BATCH] Paper up to date!
    set FILE=Paper-%Version%-%URL:~0,-1%.jar
    goto :EOF
  )
  call :FINDFILE
  if not %FILE%==x del %FILE%
  echo [BATCH] Downloading update.
  echo.
  curl https://papermc.io/api/v1/paper/%Version%/%URL:~0,-1%/download -o Paper-%Version%-%URL:~0,-1%.jar
  echo.
  echo [BATCH] Paper updated!
  set FILE=Paper-%Version%-%URL:~0,-1%.jar
) else ( call :FINDFILE )

:START
echo [BATCH] Starting server...
echo.
%JavaExe% -Xmx%MaxRam% -Xms%MinRam% -jar %FILE% %ExtraArgs%
echo.
if /I %AutoRestart%==TRUE (
  echo [BATCH] CTRL+C to exit (Auto-restarting in 5 seconds).
  ping -n 5 127.0.0.1 >nul 2>nul
  if %errorlevel%==0 goto START
)
exit /B

:FINDFILE
set FILE=x
for /F "tokens=*" %%g IN ('dir /B ^| findstr /I paper ^| findstr /I .jar') do set FILE=%%g
goto :EOF