Main Turtle Program

---------------------------------------
--------   GLOBAL VARIABLES    --------
---------------------------------------

height = 0

---------------------------------------
-- BASIC FUNCTIONS FOR TURTLE CONTROL -
---------------------------------------

local function gf(n)
  if n==nil then
    n=1
  end
  for i=1,n,1 do
    turtle.forward()
  end
end
local function gb(n)
  if n==nil then
    n=1
  end
  for i=1,n,1 do
    turtle.back()
  end
end
local function gu(n)
  if n==nil then
    n=1
  end
  for i=1,n,1 do
    turtle.up()
  end
end
local function gd(n)
  if n==nil then
    n=1
  end
  for i=1,n,1 do
    turtle.down()
  end
end
local function tl()
  turtle.turnLeft()
end
local function tr()
  turtle.turnRight()
end
local function pf()  turtle.place()       end
local function pu()  turtle.placeUp()     end
local function pd()  turtle.placeDown()   end
local function df()  return turtle.dig()  end
local function du()  turtle.digUp()       end
local function dd()  turtle.digDown()     end
local function sf()  turtle.suck()        end
local function su(n)
  if n==nil then
    while turtle.suckUp() do end
  else
    for i=1,n do
      turtle.suckUp()
    end
  end
end
local function sd(n)
  if n==nil then
    while turtle.suckDown() do end
  else
    for i=1,n do
      turtle.suckDown()
    end
  end
end
local function Df()  turtle.drop()       end
local function Du()  turtle.dropUp()     end
local function Dd(n)
  if n==nil then n=64 end
  turtle.dropDown(n)
end
local function ss(s) turtle.select(s)    end
local function cf() turtle.compare()     end
local function cu() turtle.compareUp()   end

---------------------------------------
--          BUILDING BLOCKS          --
---------------------------------------

function messageHandler()
    local event, senderId, message, protocol = os.pullEvent("rednet_message")
    if protocol ~= "worker" then
        return
    elseif message == "location" then
        print("Sending location to ID#"..tostring(senderId))
        sendLocation(senderId)
    elseif message == "dig" then
        rednet.send(senderId,"Digging...","home")
        print("Digging...")
        clearArea(4,4)
    elseif message == "reboot" then
        rednet.send(senderId,"Rebooting...","home")
        shell.run("reboot")
    else
        print("Invalid message:"..message)
    end
end

function sendLocation(host)
    local x, y, z = gps.locate()
    --print("ID:" .. homeid)
    local message = tostring(x) .. " " .. tostring(y) .. " " .. tostring(z)
    rednet.send(host,message,"home")
end

function digColumn()
    local height = 0
    while turtle.inspect() do
        df()
    end
    gf()
    while turtle.inspectUp() do
        while turtle.inspectUp() do
            du()
        end
        gu()
        height = height + 1
    end
    while height > 0 do
        gd()
        height = height - 1
    end
end

function clearArea(length, width)
    local x1,y1,z1 = gps.locate()
    local x2,y2,z2 = x1,y1,z1
    digColumn()
    x2,y2,z2 = gps.locate()

end

---------------------------------------
--           MAIN PROGRAM            --
---------------------------------------


print("Starting main...")

--Register for Rednet

rednet.host("worker","ana")
rednet.open("right")

--clearArea(4,4)

--while true do
     --messageHandler()
--end