--getting cli args

local args = {...}

--defining variables

local errors = 0

local width = 0
local range = 0

local treesCut = 0

--assigning values

if args[1] ~= nil and args[1] > 0 then
	width = args[1] * 1
else
	print("Please provide orchard width")
	errors = errors + 1
end

if args[2] ~= nil and args[2] > 0 then
	range = args[2] * 1
else
	print("Please provide orchard range")
	errors = errors + 1
end

if turtle.getFuelLevel() == 0 then
	print("No fuel left - please refill")
	errors = errors + 1
end

--defining functions

function fellTree()
	print("Felling tree...")

	local upMoves = 0

	turtle.dig()
	turtle.forward()

	while turtle.detectUp() do
		turtle.digUp()
		turtle.up()
		upMoves = upMoves + 1
	end

	--returning to ground

	for i = 1, upMoves, 1 do
		turtle.down()
	end

	print("Finished felling tree")
end

function strafeCol(column)
	if (column % 2) == 1 then
		turtle.turnRight()
		turtle.forward()
		turtle.turnRight()
	elseif (column % 2) == 0 then
		turtle.turnLeft()
		turtle.forward()
		turtle.turnLeft()
	end
end

function clearColumn(length)
	for i = 1, length, 1 do
		if turtle.detect() then
			print("Detected tree")
			fellTree()
			treesCut = treesCut + 1
		else
			if i < length then
				turtle.forward()
			end
		end
	end
end

--main section begin

if errors == 0 then

	for x = 1, width, 1 do
		clearColumn(range)

		if x < width then
			strafeCol(x)
		end
	end

	print("Returning to origin...")

	--return begin

	if (width % 2) == 1 then
		turtle.turnLeft()

		for i = 1, (width - 1), 1 do
			turtle.forward()
		end

		turtle.turnLeft()

		for i = 1, (range - 1), 1 do
			turtle.forward()
		end

		turtle.turnLeft()
		turtle.turnLeft()

	elseif (width % 2) == 0 then
		turtle.turnRight()

		for i = 1, (width - 1), 1 do
			turtle.forward()
		end

		turtle.turnRight()
	end

	print("Done")
	print("Chopped down " ..tostring(treesCut) .." trees")
end