Lazy ccRestitched Tree Farm

--[[		|	Lazy tree farm.
			|
			|	- Bonemeal goes in chest to right of turtle.
			|	- Saplings funnel into chest under turtle (Hopperhock used here since pack has Botania)
			|	- Block 8 blocks above sapling space in front of turtle
			|	- Place next to Skeleton farm for maximum  AFK efficiency
			|
			|	- Enjoy
			|
--]]

local FUEL_THRESHOLD = 80;
local SLOT_COUNT = 16;
local i, found, slotItem, currSlot, present, block, presentBelow, blockBelow = 1, false, nil, nil, turtle.inspect(), turtle.inspectDown();

-- in case chunk is unloaded or server crashes mid-routine
while not presentBelow do
	turtle.Down();
	presentBelow, blockBelow = turtle.inspectDown();
	present, block = turtle.inspect();
end
while present and (not (block.name == "minecraft:oak_sapling" or block.name == "minecraft:oak_log")) and i <= 4 do
	turtle.turnLeft();
	present, block = turtle.inspect();
	i = i + 1;
end
if i == 4 and present and not (block.name == "minecraft:oak_sapling" or block.name == "minecraft:oak_log") then
	assert(false, "Something is horribly wrong. Get Kammon.");
end

-- main function loop
while true do
	term.clear();
	print("Current fuel: "..turtle.getFuelLevel());
	print(os.getComputerLabel().." will cease function below "..FUEL_THRESHOLD..".");
	print("Please make sure to drop Charcoal and Bone Meal in the area to keep me running.");
    if turtle.getFuelLevel() < FUEL_THRESHOLD then
		found = false;
		while not found do
			for i = 1, SLOT_COUNT do
				slotItem = turtle.getItemDetail(i)
				if slotItem and slotItem.name == "minecraft:charcoal" then
				turtle.select(i);
				found = true;
				end
			end
			if not found then
				turtle.turnRight(); turtle.turnRight();
				if not turtle.suck() then
					print("Out of usable fuel. Please drop charcoal in the area.");
					os.sleep(300);
					term.clear();
				end
				turtle.turnLeft(); turtle.turnLeft();
			else
				turtle.refuel();
			end
		end
	end
	while present do
		if block.name == "minecraft:oak_sapling" then
			i = 1
			found = false;
			while i <= SLOT_COUNT and not found do
				slotItem = turtle.getItemDetail(i)
				if slotItem and slotItem.name == "minecraft:bone_meal" then
				turtle.select(i);
				found = true;
				end
				i = i + 1;
			end
			if not found then turtle.turnRight(); turtle.suck(); turtle.turnLeft() end
			turtle.place();
		elseif block.name == "minecraft:oak_log" then
			while present and block.name == "minecraft:oak_log" do
				turtle.dig();
				turtle.digUp();
				turtle.up();
				present, block = turtle.inspect();
			end
			while not turtle.detectDown() do turtle.down() end
		end
		present, block = turtle.inspect();
	end
	if not present then
		os.sleep(5);
		found = false;
		i = 1;
		while i <= SLOT_COUNT and not found do
			slotItem = turtle.getItemDetail(i);
			if slotItem and slotItem.name == "minecraft:oak_sapling" then
				turtle.select(i);
				found = true;
			end
			i = i + 1;
		end
		if not found then turtle.suckDown() end
		turtle.place();
	end
	present, block = turtle.inspect();
    for i = 1, 16 do
      slotItem = turtle.getItemDetail(i);
      if slotItem and slotItem.name == "minecraft:oak_log" then
        turtle.select(i);
        turtle.dropUp()
      end
    end
end