cacti

local fuelSlot = 16

local length = 8
local width = 8

function tF(d)
  for i = 1,d do
    while(not turtle.forward()) do
      sleep(1)
    end
  end
end

function tRefuel()
  while (turtle.getFuelLevel() < 200) do
    turtle.select(fuelSlot) --charcol in this slot
    turtle.refuel(1)
    print("Refueled")
  end
  print( "Fuel Level: ", turtle.getFuelLevel() )
end

local function selectCactus()
    turtle.select(1)
    if turtle.getItemCount(1) > 1 then
        return true
    else
        for otherSlot = 2, 15 do
            if (turtle.compareTo(otherSlot)) then
                turtle.select(otherSlot)
                return true
            end
        end
    end
    return false
end

function plant()
   selectCactus()
   turtle.placeDown()
end

function harvestRow()
  for i=1, length do
    tF(1)
    tF(1)
    if (turtle.detectDown()) then
      turtle.digDown()
      turtle.down()
      turtle.digDown()
      turtle.up()
    end
  end
end

function harvestField()
  for i=1, width do
    harvestRow()
    if (i % 2 == 0) then
      tF(1)
      turtle.turnRight()
      tF(1)
      turtle.turnRight()
    else
      tF(1)
      turtle.turnLeft()
      tF(1)
      turtle.turnLeft()
    end
  end
end

turtle.up()
turtle.up()
harvestField()
turtle.turnLeft()
tF(width)
turtle.turnLeft()
turtle.down()
turtle.down()