Minecraft ComputerCraft Turtle

-- pastebin get aK9V8ZyP turtlescript

-- Assumptions
-- +Z is towards the sky.
-- +Y is the starting direction.
-- The area is totally clear of blocks, mobs, and players.
-- The Turtle starts above a chest or ender chest outside of the structure at (x,y,z) (0,0,+2)
-- The Turtle always places downwards.
-- Block orientation is as placed downwards.
-- For consistency always face +y when placing a block.

-- The Turtle inventory is preloaded with slots 1 through 16 and never runs out from the chest.
-- Slot 1 is fuel.

--XOO
--XOO
--TXX

xHome = 0
yHome = 0
zHome = 2

local xPos = xHome
local yPos = yHome
local zPos = zHome
local xDir = 0
local yDir = 1

local blockToPlace = 0

local debugFlag = 1

--------- Stuff you need to edit ----------

Array2d = {}

Array2d[1] = 	{
			{"2","3","4","4"},
			{"5","0","7","7"},
			{"8","9","0","0"}
			}

Array2d[2] = 	{
			{"3","4","5","5"},
			{"6","7","8","8"},
			{"9","0","0","0"}
			}

Array3d = {1,2}

local XSIZE = 4
local YSIZE = 3
local ZSIZE = table.getn(Array3d)

--------- End stuff you need to edit ----------------

--123456789abcdefg
--0 denotes empty.
function convertString(str)
	if (str == "0") then
		ret = 0
	elseif (str == "1") then
		ret = 1
	elseif (str == "2") then
		ret = 2
	elseif (str == "3") then
		ret = 3
	elseif (str == "4") then
		ret = 4
	elseif (str == "5") then
		ret = 5
	elseif (str == "6") then
		ret = 6
	elseif (str == "7") then
		ret = 7
	elseif (str == "8") then
		ret = 8
	elseif (str == "9") then
		ret = 9
	elseif (str == "a") then
		ret = 10
	elseif (str == "b") then
		ret = 11
	elseif (str == "c") then
		ret = 12
	elseif (str == "d") then
		ret = 13
	elseif (str == "e") then
		ret = 14
	elseif (str == "f") then
		ret = 15
	elseif (str == "g") then
		ret = 16
	else
		ret = 0
	end
	return ret
end

function debugPrint(str)
	if (debugFlag==1) then
		print(str)
	end
end

-- Dervied from: http://www.computercraft.info/wiki/Excavate
local function turnLeft()
	turtle.turnLeft()
	xDir, yDir = -yDir, xDir
end

local function turnRight()
	turtle.turnRight()
	xDir, yDir = yDir, -xDir
end

function goTo(x,y,z)
    goToFacing(x,y,z,xDir,yDir)
end

function goToFacing( x, y, z, xd, yd )
	debugPrint("Starting at " .. xPos .. " " .. yPos .. " " .. zPos)
	debugPrint("Going to " .. x .. " " .. y .. " " .. z)
        -- This function moves on the z-axis first.
	while zPos > z do
		if turtle.down() then
			debugPrint("Went Down")
			zPos = zPos - 1
		else
			debugPrint("Can't go Down")
			sleep( 0.5 )
		end
	end

	while zPos < z do
		if turtle.up() then
			debugPrint("Went Up")
			zPos = zPos + 1
		else
			debugPrint("Can't go Up")
			sleep( 0.5 )
		end
	end

	if xPos > x then
		while xDir ~= -1 do
			if (xDir == 0 and yDir == -1) then
				debugPrint("Turning Right xPos > x")
				turnRight()
			else
				debugPrint("Turning Left xPos > x")
				turnLeft()
			end
		end
		while xPos > x do
			if turtle.forward() then
				debugPrint("Went Forward xPos > x")
				xPos = xPos - 1
			else
				debugPrint("Can't go Forward xPos > x")
				sleep( 0.5 )
			end
		end
	elseif xPos < x then
		while xDir ~= 1 do
			if (xDir == 0 and yDir == 1) then
				debugPrint("Turning Right xPos < x")
				turnRight()
			else
				debugPrint("Turning Left xPos < x")
				turnLeft()
			end
		end
		while xPos < x do
			if turtle.forward() then
				debugPrint("Went Forward xPos < x")
				xPos = xPos + 1
			else
				debugPrint("Can't go Forward xPos < x")
				sleep( 0.5 )
			end
		end
	end

	if yPos > y then
		while yDir ~= -1 do
			if ( xDir == 1 and yDir == 0) then
				debugPrint("Turning Right yPos > y")
				turnRight()
			else
				debugPrint("Turning Left yPos > y")
				turnLeft()
			end
		end
		while yPos > y do
			if turtle.forward() then
				debugPrint("Went Forward yPos > y")
				yPos = yPos - 1
			else
				debugPrint("Can't go Forward yPos > y")
				sleep( 0.5 )
			end
		end
	elseif yPos < y then
		while yDir ~= 1 do
			if ( xDir == -1 and yDir == 0) then
				debugPrint("Turning Right yPos < y")
				turnRight()
			else
				debugPrint("Turning Left yPos < y")
				turnLeft()
			end
		end
		while yPos < y do
			if turtle.forward() then
				debugPrint("Went Forward yPos < y")
				yPos = yPos + 1
			else
				debugPrint("Can't go Forward yPos < y")
				sleep( 0.5 )
			end
		end
	end

	while yDir ~= yd or xDir ~= xd do
		if (xd == yDir and yd == -xDir) then
			debugPrint("Returning Facing Right")
			turnRight()
		else
			debugPrint("Returning Facing Left")
			turnLeft()
		end
	end
end

-- Refill the inventory from the chest
function refill()
	for i=1,16 do
	turtle.select(i)
	turtle.suckDown()
	end
	refuel()
end

function refuel()
	turtle.select(1)
	if(turtle.refuel(63)) then
		debugPrint("Refueled")
	else
		debugPrint("Could not Refuel")
	end
	fuel=turtle.getFuelLevel()
	debugPrint("Fuel is " .. fuel)
end

function returnHome()
	-- Goes to 0,0 first.
	goTo(xHome,yHome,zPos)
	goTo(xHome,yHome,zHome)
end

function returnHomeFacing01()
	-- Goes to 0,0 first.
	goTo(xHome,yHome,zPos)
	goToFacing(xHome,yHome,zHome,0,1)
end

debugPrint("XSIZE, YSIZE, ZSIZE" .. table.getn(Array2d[1][1]) .. " " .. table.getn(Array2d[1]) .. " " .. ZSIZE)

refill()
for zIndex =1,ZSIZE do
	for yIndex=1,YSIZE do
		for xIndex=1,XSIZE do
			blockToPlace = convertString(Array2d[Array3d[zIndex]][1+YSIZE - yIndex][xIndex]);
			fuel=turtle.getFuelLevel()
			debugPrint("Prepare to Place " .. blockToPlace .. " at " .. xIndex .. " " .. yIndex .. " " .. " " .. zIndex)

			-- If we don't have the material or are low on fuel, return home, refill, come back to the z-axis.
			if (blockToPlace ~= 0) then
				if (turtle.getItemCount(blockToPlace) < 2 or fuel < 200) then
					debugPrint("Returning Home")
					returnHome()
					debugPrint("Refilling")
					refill()
				end
				-- Go to and face +y
				debugPrint("goToFacing " .. xIndex .. " " .. yIndex .. " " .. zIndex + 1 .. " - - 0 1")
				goToFacing( xIndex, yIndex, zIndex+1, 0, 1 )
				debugPrint("Select Block")
				turtle.select(blockToPlace)
				turtle.placeDown()
			end
		end
	end
end
returnHomeFacing01()
debugPrint("Done")