Turtle Coordinate Tracker

print("Where Am I - Coordinates for turtles. Type help() for help.")
print("Also, do NOT use the normal turtle.forward and such functions, as that will mess up the internal coordinates of the turtle.")
if fs.exists("coords") then
  local file = fs.open("coords", "r")
  X = file.readLine()
  Y = file.readLine()
  Z = file.readLine()
  face = file.readLine()
  file.close()
  X = tonumber(X)
  Y = tonumber(Y)
  Z = tonumber(Z)
  face = tonumber(face)
  print("Initialized settings.")
end
if fs.exists("waypoints") then
  local file = fs.open("waypoints", "r")
  waypoints = {}
  local line = file.readLine()
  while line do
    table.insert(waypoints, line)
    line = file.readLine()
  end
  print("Waypoints Initilialized.")
end
function help(page)
  if type(page) == "nil" then
    page = 1
  end
  Page = tonumber(page)
  if type(Page) ~= "number" then
    error("Bad argument: Number expected, got "..page.."!")
  elseif Page > 6 or Page < 1 then
    error("Bad argument: Integer expected between 1 and 4, got "..Page.."!")
  end
  if Page == 1 then
    print("---------------Help menu---------------")
    print("----------Viewing Page 1 of 6----------")
    print("help(page)")
    print("-Shows these help text pages.")
    print("-Perameraters: Takes the page number you whish to view help on.")
    print("turtle.setCoords(x,y,z,dir)")
    print("-Will set the coords of the turtle.")
    print("-Perameraters: Integers for X,Y and Z, and the initial direction the turtle is facing.")
  elseif Page == 2 then
    print("---------------Help Menu---------------")
    print("----------Viewing Page 2 of 6----------")
    print("turtle.getCoords()")
    print("-Prints the current coordinates of the turtle.")
    print("turtle.move(dir, amount)")
    print("-Moves turtle in indicated direction.")
    print("-Perameraters: The direction the turtle should move, and how many blocks that way. Takes 'front', 'down', 'forward', 'back', 'left', and 'right' as arguments.")
  elseif Page == 3 then
    print("---------------Help Menu---------------")
    print("----------Viewing Page 3 of 6----------")
    print("turtle.turn(string direction)")
    print("-Turn the turtle in the specified direction.")
    print("-Perameraters: The direction the turtle should turn. (left, right, or back)")
  elseif Page == 4 then
    print("-----Help Menu-Viewing Page 4 of 6-----")
    print("setWaypoint(X,Y,Z,name,)")
    print("-Sets a named waypoint for the turtle at the indicated location. Also, if specified, will make the turtle go to height. Useful if the waypoint is under something.")
    print("-Perameraters: Takes Integers for X, Y, and Z. Takes a name for the waypoint. Will also take an integer for the height the turtle should reach before going.")
  elseif Page == 5 then
    print("---------------Help Menu---------------")
    print("----------Viewing Page 5 of 6----------")
    print("deleteWaypoint(name)")
    print("-Deletes the specified waypoint.")
    print("-Perameraters: Takes the name of the waypoint that should be deleted.")
    print("listWaypoints()")
    print("Lists all the available waypoints.")
    print("turtle.gotoWaypoint(name)")
  elseif Page == 6 then
    print("---------------Help Menu---------------")
    print("----------Viewing Page 6 of 6----------")
    print("-Has the turtle go to the waypoint.")
    print("-Perameraters: Takes the name of the waypoint the turtle should go to.")
    print("Coordinates are saved as follows: X coord: X, Y coord: Y, Z coord: Z, Direction: face")
  end
end
local function reinitialize()
  file = fs.open("coords", "w")
  file.writeLine(X)
  file.writeLine(Y)
  file.writeLine(Z)
  file.writeLine(face)
  file.close()
end
function turtle.setCoords(x,y,z,dir)
  X = x
  Y = y
  Z = z
  face = string.lower(dir)
  if face == "north" then
    face = 0
  elseif face == "south" then
    face = 2
  elseif face == "east" then
    face = 3
  elseif face == "west" then
    face = 1
  else
    face = 0
  end
  while type(X) ~= "number" do
    print("X is not a number.")
    X = tonumber(read())
  end
  while type(Y) ~= "number" do
    print("Y is not a number.")
    Y = tonumber(read())
  end
  while type(Z) ~= "number" do
    print("Z is not a number.")
    Z = tonumber(read())
  end
  reinitialize()
end
function turtle.getCoords()
  print("X: "..X)
  print("Y: "..Y)
  print("Z: "..Z)
  if face == 0 then
    print("facing: north")
  elseif face == 1 then
    print("facing: west")
  elseif face == 2 then
    print("facing: south")
  else
    print("facing: east")
  end
end
function turtle.turn(dir)
  if dir == "left" then
    turtle.turnLeft()
    face = ((face + 1) + 4) % 4
  elseif dir == "right" then
    turtle.turnRight()
    face = ((face - 1) + 4) % 4
  elseif dir == "back" then
    turtle.turnLeft()
    turtle.turnLeft()
    face = ((face + 2) + 4) % 4
  end
  reinitialize()
end
function turtle.move(dir,a)
  if a == nil then
    a = 1
  end
  if dir == "up" then
    for i=1,a do
      if turtle.up() then
        Y = Y + 1
      end
    end
  elseif dir == "down" then
    for i=1,a do
      if turtle.down() then
        Y = Y - 1
      end
    end
  elseif dir == "forward" then
    for i=1,a do
      if turtle.forward() then
        if face == 0 then
          Z = Z - 1
        elseif face == 2 then
          Z = Z + 1
        elseif face == 1 then
          X = X - 1
        elseif face == 3 then
          X = X + 1
        end
      end
    end
  elseif dir == "back" then
    for i=1,a do
      if turtle.back() then
        if face == 0 then
          Z = Z + 1
        elseif face == 2 then
          Z = Z - 1
        elseif face == 1 then
          X = X + 1
        elseif face == 3 then
          X = X - 1
        end
      end
    end
  elseif dir == "left" then
    for i=1,a do
      if turtle.turnLeft() then
        face = ((face + 1) + 4) % 4
      end
      if turtle.forward() then
        if face == 0 then
          Z = Z - 1
        elseif face == 2 then
          Z = Z + 1
        elseif face == 1 then
          X = X - 1
        elseif face == 3 then
          X = X + 1
        end
      end
      if turtle.turnRight() then
        face = ((face - 1) + 4) % 4
      end
    end
  elseif dir == "right" then
    for i=1,a do
      if turtle.turnRight() then
        face = ((face - 1) + 4) % 4
      end
      if turtle.forward() then
        if face == 0 then
          Z = Z - 1
        elseif face == 2 then
          Z = Z + 1
        elseif face == 1 then
          X = X - 1
        elseif face == 3 then
          X = X + 1
        end
      end
      if turtle.turnLeft() then
        face = ((face + 1) + 4) % 4
      end
    end
  end
  reinitialize()
end
function setWaypoint(x,y,z,name,yLimit)
  if waypoints == nil then
    waypoints = {}
  end
  if yLimit == nil then
    yLimit = 256
  end
  table.insert(waypoints,name)
  local x = tonumber(x)
  local y = tonumber(y)
  local z = tonumber(z)
  local yLimit = tonumber(yLimit)
  while type(x) ~= "number" do
    print("X is not an integer")
    x = tonumber(read())
  end
  while type(y) ~= "number" do
    print("Y is not an integer")
    y = tonumber(read())
  end
  while type(z) ~= "number" do
    print("Z is not an integer")
    z = tonumber(read)
  end
  while type(yLimit) ~= "number" do
    print("The Y Limit is not an integer")
    yLimit = tonumber(read())
  end
  table.insert(waypoints,x)
  table.insert(waypoints,y)
  table.insert(waypoints,z)
  table.insert(waypoints,yLimit)
  file = fs.open("waypoints", "a")
  file.writeLine(name)
  file.writeLine(x)
  file.writeLine(y)
  file.writeLine(z)
  file.writeLine(yLimit)
  file.close()
end
function deleteWaypoint(name)
  for i=#waypoints,1,-1 do
    if waypoints[i] == name then
      table.remove(waypoints, i)
      table.remove(waypoints, i)
      table.remove(waypoints, i)
      table.remove(waypoints, i)
      table.remove(waypoints, i)
      local file = fs.open("waypoints", "w")
      for key,value in pairs(waypoints) do
        file.writeLine(value)
      end
      file.close()
    end
  end
end
function listWaypoints()
  for i=1,#waypoints do
    if type(tonumber(waypoints[i])) == "nil" then
      print(waypoints[i])
    end
  end
end
function turtle.gotoWaypoint(name)
  local turtleGo = false
  for key,value in pairs(waypoints) do
    if value == name then
      gotoX = waypoints[key + 1]
      gotoY = waypoints[key + 2]
      gotoZ = waypoints[key + 3]
      yLimit = waypoints[key + 4]
      gotoX = tonumber(gotoX)
      gotoY = tonumber(gotoY)
      gotoZ = tonumber(gotoZ)
      yLimit = tonumber(yLimit)
      turtleGo = true
    end
  end
  if turtleGo == false then
    error("Bad argument: Expected listed waypoint, got "..name.."!")
  end
  while (((gotoX ~= X) or (gotoY ~= Y)) or (gotoZ ~= Z)) and turtleGo do
    if yLimit > Y then
      local skyDif = yLimit - Y
      turtle.move("up",skyDif)
    elseif yLimit < Y then
      local skyDif = Y - yLimit
      turtle.move("down",skyDif)
    end
    while gotoX ~= X do
      if gotoX > X then
        local Xdif = gotoX - X
        if face == 0 then
          turtle.turn("right")
        elseif face == 1 then
          turtle.turn("back")
        elseif face == 2 then
          turtle.turn("left")
        end
        turtle.move("forward",Xdif)
      else
        local Xdif = X - gotoX
        if face == 0 then
          turtle.turn("left")
        elseif face == 3 then
          turtle.turn("back")
        elseif face == 2 then
          turtle.turn("right")
        end
        turtle.move("forward",Xdif)
      end
    end
    while gotoZ ~= Z do
      if gotoZ > Z then
        local Zdif = gotoZ - Z
        if face == 0 then
          turtle.turn("back")
        elseif face == 1 then
          turtle.turn("left")
        elseif face == 3 then
          turtle.turn("right")
        end
        turtle.move("forward",Zdif)
      else
        local Zdif = Z - gotoZ
        if face == 1 then
          turtle.turn("right")
        elseif face == 2 then
          turtle.turn("back")
        elseif face == 3 then
          turtle.turn("left")
        end
        turtle.move("forward",Zdif)
      end
    end
    while gotoY ~= Y do
      if gotoY < Y then
        local Ydif = Y - gotoY
        turtle.move("down",Ydif)
      elseif gotoY > Y then
        local Ydif = gotoY - Y
        turtle.move("up",Ydif)
      end
    end
  end
end