ComputerCraft Elevator Turtle Code

-- Define some constants for the elevator - make editing for other elevators easier

-- Optionally give names to some floors. If a name is specified, it will be matched against this list to be converted to a floor number.
floorNames =
{lobby = 1, ground = 1, cafe = 7,
penthouse = 19, basement = 0,
cloudcafe = 7, library = 3,
storage = 2, cave = -13}

-- The highest floor number the elevator can travel to.
highFloor = 19

-- The lowest floor number to which the elevator can travel. Not required to be 1 - 1 usually represents a ground floor, and there can be basements and sub-basements as well.
lowFloor = -13

-- The floor it is assumed the turtle is on if it can move no further down. This can be lower, but not higher, than lowFloor.
shaftBottom = -13

-- Floors which cannot be chosen as elevator destinations. Attempting to take an elevator to such a floor from within will fail. Attempting to call the elevator to the floor from outside will still succeed.
invalidFloors =
{6, 8, 18, -10, -11, -12}

-- Use the above list as a blacklist instead of a blacklist.
blacklistFloors = true

-- The distance in blocks an elevator must travel from one floor to be on the next.
floorDistance = 6

-- Do lighting?
doLighting = false

-- These functions are for moving.
function u(m)
  n = m or 1
  for a = 1, n do
    if turtle.detectUp() then
      return false
    end
    if doLighting then rs.setOutput("front", false) end
    while not turtle.up() do end
    if doLighting then rs.setOutput("front", true) end
  end
  return true
end
function d(m)
  n = m or 1
  for a = 1, n do
    if turtle.detectDown() then
      return false
    end
    if doLighting then rs.setOutput("front", false) end
    while not turtle.down() do end
    if doLighting then rs.setOutput("front", true) end
  end
  return true
end

currFloor = 0
callToFloor = 0

function startup()
  if doLighting then rs.setOutput("front", true)
    else rs.setOutput("front", false) end
  rednet.open("right")
  rednet.broadcast("TO " .. shaftBottom)
  rs.setOutput("left", true)
  while d() do end
  currFloor = shaftBottom
  callToFloor = currFloor
  rednet.broadcast("AT " .. currFloor)
  run = true
  while run do
    callToFloor = -32768
    rs.setOutput("back", true)
    parallel.waitForAny(acceptCall, queryFloor)
    rs.setOutput("back", false)
    if callToFloor ~= -32768 then
      travelToFloor(callToFloor)
    else
      run = false
    end
  end
end

acceptCall = function()
  sleep(10)
  waitingForCall = true
  while waitingForCall do
    sender, message, distance = rednet.receive()
    if string.sub(message, 1, 5) == "CALL " then
      callToFloor = tonumber(string.sub(message, 6))
      if callToFloor ~= nil then waitingForCall = false
        else callToFloor = currFloor end
    end
  end
end

queryFloor = function()
  invalidInput = true
  while invalidInput do
    print("Enter the floor to which to travel: ")
    query = io.read():lower()
    if tonumber(query) == nil then query = floorNames[query]
      else query = tonumber(query) end
    if query ~= nil then
      query = math.floor(query)
      if query >= lowFloor and query <= highFloor then
        invalidFloor = false
        for a = 1, #invalidFloors do
          if query == invalidFloors[a] then invalidFloor = true end
        end
        invalidInput = (invalidFloor and blacklistFloors) or (not invalidFloor and not blacklistFloors)
      end
    end
    if invalidInput then print("I'm sorry but that is not a valid floor. Please try again.") end
  end
  callToFloor = query
end

function travelToFloor(destination)
  print("Traveling to floor " .. destination)
  sleep(0.1)
  rednet.broadcast("TO " .. destination)
  while currFloor ~= destination do
    if currFloor > destination then travelOneFloor(false)
    else travelOneFloor(true) end
  end
end

function travelOneFloor(up)
  if up then
    u(floorDistance)
    currFloor = currFloor + 1
  else
    d(floorDistance)
    currFloor = currFloor - 1
  end
  rednet.broadcast("AT " .. currFloor)
end

startup()