[ComputerCraft] Quarry: Mining Turtle

xCoord = 267
yCoord = 69
zCoord = -1594

xHome = 267
yHome = 69
zHome = -1594

xQuarry = 999
zQuarry = 999
yQuarry = 150

xProgress = 999
zProgress = 999
yProgress = 150
oProgress = 1

orientation = 3
orientations = {"north", "east", "south", "west"}

zDiff = {-1, 0, 1, 0}
xDiff = {0, 1, 0, -1}

lineLength = 10
lines = 10
yMin = 999

jobAvailable = true
manager = 9

function inventoryFull()
  turtle.select(9)
  full = turtle.getItemCount(9) > 0
  turtle.select(1)
  return full
end

function look(direction)
  while direction ~= orientations[orientation] do
    right()
  end
end

function moveForward()
  xCoord = xCoord + xDiff[orientation]
  zCoord = zCoord + zDiff[orientation]

  turtle.dig()
  moved = turtle.forward()
  while not(moved) do
    turtle.dig()
    moved = turtle.forward()
  end
end


function left()
  orientation = orientation - 1
  orientation = (orientation - 1) % 4
  orientation = orientation + 1

  turtle.turnLeft()
end

function right()
  orientation = orientation - 1
  orientation = (orientation + 1) % 4
  orientation = orientation + 1

  turtle.turnRight()
end

function moveUp()
  yCoord = yCoord + 1

  turtle.digUp()

  moved = false
  while not(moved) do
    moved = turtle.up()
  end
end

function moveDown()
  yCoord = yCoord - 1

  turtle.digDown()

  moved = false
  while not(moved) do
    moved = turtle.down()
  end

  if yMin > yCoord then
    yMin = yCoord
  end
end

function goto(xTarget, zTarget, yTarget)
  while yTarget < yCoord do
     moveDown()
  end
  while yTarget > yCoord do
    moveUp()
  end

  if xTarget < xCoord then
    look("west")
    while xTarget < xCoord do
       moveForward()
    end
  end
  if xTarget > xCoord then
    look("east")
    while xTarget > xCoord do
      moveForward()
    end
  end
  if zTarget < zCoord then
    look("north")
    while zTarget < zCoord do
      moveForward()
    end
  end
  if zTarget > zCoord then
    look("south")
    while zTarget > zCoord do
      moveForward()
    end
  end
end

function returnItems()
  xProgress = xCoord
  zProgress = zCoord
  yProgress = yCoord
  oProgress = orientation

  goto(xHome, zHome, yHome)
  look("north")
  for i = 1,9 do
    turtle.select(i)
    turtle.drop()
  end
  turtle.select(1)

  goto(xProgress, zProgress, yProgress)
  look(orientations[oProgress])
end

function digLine()
  for i = 1,lineLength do
    if inventoryFull() then
      returnItems()
    end
    moveForward()
  end
end

function digLayer()
  for i = 1,lines do
    digLine()
    if (i%2) == 1 and i < lines then
      left()
      moveForward()
      left()
    elseif i < lines then
      right()
      moveForward()
      right()
    end
  end
  goto(xQuarry, zQuarry, yCoord)
  look("north")
  moveDown()
end

function digQuarry(xTarget, zTarget, yTarget)
  xQuarry = xTarget
  zQuarry = zTarget
  yQuarry = yTarget

  goto(xQuarry, zQuarry, yQuarry)
  while yMin > 7 do
    digLayer()
  end
  goto(xQuarry, zQuarry, yQuarry)
  goto(xHome, zHome, yHome)
  yMin = 999
end

function getJob()
  while jobAvailable do
    print("Requesting job")
    rednet.send(manager, "getJob")
    id, message, dis = rednet.receive()

    if message == "yes" then
      id, xRec, dis = rednet.receive()
      id, zRec, dis = rednet.receive()
      id, yRec, dis = rednet.receive()

      xQuarry = tonumber(xRec)
      zQuarry = tonumber(zRec)
      yQuarry = tonumber(yRec)
      print("Job at "..xQuarry.." "..zQuarry.." "..yQuarry)

      digQuarry(xQuarry, zQuarry, yQuarry)
      print("Finished job")
    elseif message == "no" then
      print("No more jobs")
      jobAvailable = false
    end
  end
end

rednet.close("right")
rednet.open("right")

getJob(273, 69, -1594)