treeplant

--- Turtle which can plant tree saplings. Orients itself using line of cobble (item in Direction Guide) and plans (Turn around guide)
local SLEEP_BETWEEN_TURNS = 300
local SLEEP_REFUEL_FAIL = 60

local DIR_LEFT = "left"
local DIR_RIGHT = "right"

local direction = DIR_LEFT
local ITEM_TO_PLANT = 1
local ITEM_FUEL = 14
local ITEM_TURN_AROUND_GUIDE = 15
local ITEM_DIRECTION_GUIDE = 16

local REFUEL_OK = "ok"
local REFUEL_ERROR = "error"

function turnFinal()
	if direction == DIR_LEFT then
		turtle.turnLeft()
	else
		turtle.turnRight()
	end
end

function turnToCorrectDirection()
	turtle.select(ITEM_DIRECTION_GUIDE)
	for i=1,4 do
		local doBreak = 0
		if turtle.compare() then
			turnFinal()
			break
		else
			turtle.turnLeft()
		end
	end
end

function moveForward()
	for i=1,10 do
		if turtle.forward() then
			return true
		end
	end
	return false
end

function plant()
	--turn to placing direction
	if direction == DIR_LEFT then
		turtle.turnLeft()
	else
		turtle.turnRight()
	end
	turtle.select(ITEM_TO_PLANT)
	turtle.place()
	-- turn back
	if direction == DIR_LEFT then
		turtle.turnRight()
	else
		turtle.turnLeft()
	end
end

function detectTurn()
	turtle.select(ITEM_TURN_AROUND_GUIDE)
	return turtle.compare()
end

function reverseDirection()
	if direction == DIR_LEFT then
		direction = DIR_RIGHT
	else
		direction = DIR_LEFT
	end
	print("New direction"..direction)
end


--- return value: 1 - everything ok, 0 - not enough fuel
function refuel()
	print("Current fuel level: "..turtle.getFuelLevel())
	if turtle.getFuelLevel() < 200 then
		if turtle.getItemCount(ITEM_FUEL) > 1 then
			turtle.select(ITEM_FUEL)
			--refuel at most 5 items, but do not leave slot empty and protect against wrong argument error (if <0 in refuel)
			if turtle.refuel(math.max(0,math.min(5,turtle.getItemCount(ITEM_FUEL)-1))) then
				return REFUEL_OK
			else
				print("Refuel failed for unknown reason")
				return REFUEL_ERROR
			end
		else
			print("Refuel failed: low on fuel and no extra fuel")
			return REFUEL_ERROR
		end
	else
		return REFUEL_OK
	end
end

-------------------------------------------

while true do
	turnToCorrectDirection()
	while not detectTurn() do
		plant()
		if not moveForward() then
			break
		end
	end
	reverseDirection()
	print("Sleeping")
	sleep(SLEEP_BETWEEN_TURNS)
	for i=2,2 do
		turtle.select(i)
		turtle.transferTo(1, math.max(0,turtle.getItemCount(i)-1))
	end
	if direction == DIR_RIGHT then
		while not (refuel() == REFUEL_OK) do
			sleep(SLEEP_REFUEL_FAIL)
		end
	end
end