9x9_farm_setup

--[[
This program is designed to setup a 9x9 farm on a level surface with a
water source block in the middle. These dimensions account for the
maximum range a tilled dirt can be from water. If you would prefer to
have the farm level with your terrain rather than raised one above it
you need only clear a 9x9 hole in the ground and ensure your turtle is
placed at the block height you want the farm built at. This program
can handle wheat, carrots, and potatoes. A farming turtle will require
the following items in it's inventory slots:

1) 64 dirt
2) 16 dirt
4) bucket of water
5) 64 seeds, carrots, or potatoes
6) 16 seeds, carrots, or potatoes
16) Fuel (preferably coal, charcoal, or a lava bucket)

Future versions will support pumpkins and melons along with
harvesting/replanting code.
]]--

local step = 1 --used to track progression
local count = 64 --used to track inventory slots
local n = 1 --used to track slot selection

function fuel()
  if turtle.getFuelLevel() < 10 then
    select(16)
    turtle.refuel(1)
  end
end

--assorted functions to shorten/tidy my actual code
function left(reps)
  for x=1,reps do
   turtle.turnLeft()
  end
end

function right(reps)
  for x=1,reps do
   turtle.turnRight()
  end
end

function back(reps)
  for x=1,reps do
   fuel()
   turtle.back()
  end
end

function forward(reps)
  for x=1,reps do
   fuel()
   turtle.forward()
  end
end

function up(reps)
  for x=1,reps do
   fuel()
   turtle.up()
  end
end

function down(reps)
  for x=1,reps do
   fuel()
   turtle.down()
  end
end

function pDown()
  turtle.placeDown()
end

function pUp()
  turtle.placeUp()
end

function place()
  turtle.place()
end

function dDown()
  turtle.digDown()
end

function select(slot)
  turtle.select(slot)
end

--Turtle positions itself and begins creating the farm
up(1)
right(2)
back(1)
select(1)
pDown()
count = count - 1

--Turtle creates the farm when z == 1 and then tills and plants when z == 2
for z=1,2 do
  for x=1,9 do
    for y=1,8 do
      if z == 1 then
        if count > 0 then
          n=1
        else
          n=2
        end
      else
        if count > 0 then
          n=5
        else
          n=6
        end
      end
      if turtle.getItemCount(1) == 24 and count == 24 then --tracks for water placement
        back(2)
        down(1)
        select(4)
        place()
        up(1)
        forward(1)
      else
        back(1)
        select(n)
        pDown()
      end
      count = count - 1
    end
    if step == 1 then
      select(n)
      pDown()
      right(1)
      back(1)
      right(1)
      if not pDown() then
        select(n+1)
        pDown()
      end
      step = 2
      count = count - 2
    else
      select(n)
      pDown()
      left(1)
      back(1)
      left(1)
      if not pDown() then
        select(n+1)
        pDown()
      end
      step = 1
      count = count - 2
    end
  end
  for a=1,2 do
    right(1)
    forward(1)
  end
  up(1)
  count = 64
end