[CC] extensions installer

local installed = fs.exists( "extensions" )
if installed then
  print "Extensions already downloaded, reinstall? (y/n)"
  while true do
    local _, key = os.pullEvent( "key" )
    -- remove any stray character events
    os.startTimer(0.1)
    os.pullEvent()
    if key == keys.y then
      shell.run( "delete extensions", "w" )
      if fs.exists( "extensions.cfg" ) then
        local file = fs.open( "extensions.cfg", "r" )
        local text = file.readAll()
        file.close()
        if text:find( "^return " ) then
          print "Fixing old configuration file"
          file = fs.open( "extensions.cfg", "w" )
          text = text:gsub( "^return ", "" )
          file.write( text )
          file.close()
        end
      end
      break
    elseif key == keys.n then
      print "Canceling installation"
      return
    end
  end
end

print "Installing extensions"
shell.run( "pastebin get 7Nq6R70n extensions" )

if installed then
  shell.run( "extensions reload" )
else
  shell.run( "extensions" )
  print "Adding extensions to startup"
  local file = fs.open("startup", fs.exists("startup") and "a" or "w")
  file.writeLine( 'shell.run( "extensions" )' )
  file.close()
end