farm

--pastebin get Wn9kYJcT farm
local lenght,width = 9,9
local pos = {
        ["x"]   = 0,
        ["y"]   = -1,
}
local direction = {
	["forw"]  = 1,
	["right"] = 2,
	["back"]  = 3,
	["left"]  = 4,
}
local dir = direction.forw

local function farm()
	turtle.digDown()
	turtle.placeDown()
end

local function takeSeeds()
	turtle.select(1)
	local ammount = lenght * width
	if ammount > 64 then ammount = 64 end
	if turtle.getItemCount(1) < ammount then
		print("Don't have seeds")
	end
	while turtle.getItemCount(1) < ammount do
		turtle.suckDown()
		os.sleep(1)
	end
	print("I took the seeds")
end

local function returnSupplies()
	for i = 2,16 do
		if turtle.getItemCount(i)>0 then
			turtle.select(i)
			turtle.drop()
		end
	end
	turtle.select(1)
end

local function turnRight()
	dir = dir + 1
	if dir == 5 then dir = direction.forw end
--		saveState()
	turtle.turnRight()
end

local function turnLeft()
	dir = dir - 1
	if dir == 0 then dir = direction.left end
--		saveState()
	turtle.turnLeft()
end

local function forward()
	turtle.forward()
	if dir == direction.forw then
		pos.y = pos.y + 1
	elseif dir == direction.right then
		pos.x = pos.x + 1
	elseif dir == direction.back then
		pos.y = pos.y - 1
	elseif dir == direction.left then
		pos.x = pos.x - 1
	end
end

function goTo( x, y, d)
        if pos.x > x then
                while dir ~= direction.left do
                        turnRight()
                end
                while pos.x > x do
                        forward()
                end
        elseif pos.x < x then
                while dir ~= direction.right do
                        turnRight()
                end
                while pos.x < x do
                        forward()
                end
        end
        if pos.y > y then
                while dir ~= direction.back do
                        turnLeft()
                end
                while pos.y > y do
                        forward()
                end
        elseif pos.y < y then
                while dir ~= direction.forw do
                        turnLeft()
                end
                while pos.y < y do
                        forward()
                end
        end
        while d ~= dir do
                turnLeft()
        end
end

local function endFarm()
	return (pos.x == width - 1) and ((pos.y == lenght - 1 and math.fmod(pos.x,2) == 0) or (pos.y == 0 and math.fmod(pos.x,2) == 1))
end

local function main()
	while not endFarm() do
		if math.fmod(pos.x,2) == 0 then -- 010101
			if pos.y == lenght-1 then
				if dir == direction.forw then
					turnRight()
				elseif dir == direction.right then
					forward()
					farm()
				end
			elseif pos.y == 0 and dir == direction.right then
				turnLeft()
			else
				forward()
				farm()
			end
		else
			if pos.y == 0 then
				if dir == direction.back then
					turnLeft()
				elseif dir == direction.right then
					forward()
					farm()
				end
			elseif pos.y == lenght-1 and dir == direction.right then
					turnRight()
			else
				forward()
				farm()
			end
		end
	end
	goTo( 0, -1, direction.back)
	returnSupplies()
	goTo( 0, -1, direction.forw)
end

while true do
	if redstone.getInput("top") == true then
		takeSeeds()
		main()
	end
	os.sleep(5)
end