startup

rednet.open("bottom")
local sensor = peripheral.wrap("back")
local monitor = peripheral.wrap("top")
monitor.setTextScale(0.5)

if rs.getInput("top") then
  return
end

rs.setOutput("front",true)

function getCartAt(x,y,z)
  local carts = sensor.getMinecartIds()

  for num, id in pairs(carts) do
    local cart
    pcall(function() cart = sensor.getMinecartData(id) end)
    if cart then
      local pos = cart.position
      if (math.abs(x - pos.x) < 1.0) and (math.abs(y - pos.y) < 1.0) and (math.abs(z - pos.z) < 1.0) then
        return cart
      end
    end
  end
  return nil
end

local cart = nil

os.startTimer(1)

while true do
  local event, senderId, message = os.pullEvent()

  if event == "timer" then
    monitor.clear()

    cart = getCartAt(-1,1,1)
    --if cart then
      --print(cart.position.x..", "..cart.position.y..", "..cart.position.z)
      --os.sleep(10000)
    --end
    if cart then
      if cart.riddenBy then
        local username = cart.riddenBy.username
        local heldItem = cart.riddenBy.heldItem
        local validTicket = false
        local destination = "none"
        local ticketid = "ID: ungueltig"
        if heldItem then
          if heldItem.printout then
            local text = heldItem.printout.text
            if text then
              destination = text[1]
              ticketid = text[2]
              validTicket = true
            end
          end
        end
        if validTicket then
          monitor.setCursorPos(1,1)
          monitor.write("Gute Fahrt nach")
          monitor.setCursorPos(1,2)
          monitor.write(destination)
          monitor.setCursorPos(1,3)
          monitor.write(username..".")
          monitor.setCursorPos(1,5)
          monitor.write(ticketid)
          print("abfahrt")
          rednet.broadcast("abfahrt")
          rs.setOutput("front",false)
          os.sleep(3)
          rs.setOutput("front",true)
        else
          monitor.setCursorPos(1,1)
          monitor.write("Wilkommen")
          monitor.setCursorPos(1,2)
          monitor.write(username)
          monitor.setCursorPos(1,4)
          monitor.write("Die Fahrkarte")
          monitor.setCursorPos(1,5)
          monitor.write("vorzeigen bitte.")
        end
      end
    else
      rs.setOutput("left",true)
      os.sleep(0.1)
      rs.setOutput("left",false)
    end

    os.startTimer(1)
  end

  if event == "rednet_message" then
    if message then
      if message == "abfahrt" then
        print("Wait 3 sec...")
        os.sleep(3)
      end
    end
  end
end