farm

-- NO EDIT
local CHEST_SLOT = 2
local FUEL_SLOT = 1
local SEED_SLOT1 = 3

function inventoryFull()
  if turtle.getItemCount(13) > 0 or turtle.getItemCount(14) > 0 or turtle.getItemCount(15) > 0 or turtle.getItemCount(16) > 0 then
    return true
  else
    return false
  end
end

function emptyInventory()
  turtle.select(CHEST_SLOT)
  turtle.place()
  sleep(0.5)

  for i = 4, 16, 1 do
      while turtle.getItemCount(i) > 0 do
          turtle.select(i)
          turtle.drop()
          sleep(0.5)
      end
  end
  turtle.select(CHEST_SLOT)
  turtle.dig()
end

function checkFuelAndRefuelIfNeeded()
  if turtle.getFuelLevel() < 5 then
    turtle.select(FUEL_SLOT)
    turtle.refuel(turtle.getItemCount(FUEL_SLOT)-1)
  end
end

function dig()

  turtle.digDown()
  placeSeed()

  turtle.forward()

end

function placeSeed()
  turtle.select(SEED_SLOT1)
  turtle.placeDown()
  sleep(0.5)
end

function goToNextRow(currentRow)
  if currentRow % 2 == 0 then
    turtle.turnLeft()
    turtle.forward()
    turtle.turnLeft()
    turtle.forward()
  else
    turtle.turnRight()
    turtle.forward()
    turtle.turnRight()
    turtle.forward()
  end
end

-- main
print("Length: ")
local length = read()
print("Width: ")
local width = read()

for currentRow = 1, width, 1 do
  if (currentRow > 1) then
    goToNextRow(currentRow)
  end

  for i = 1, length, 1 do

    if inventoryFull() then
      emptyInventory()
    end

    checkFuelAndRefuelIfNeeded()

    dig()
  end
end

emptyInventory()