BridgeBuilder

-- slots 1-8 Sand
-- slots 9-12 cobblestone
-- slot 13 empty
-- slot 14 cobblestone
-- slot 15 sand
-- slot 16 coal

local w,h = term.getSize()
local selection = 0
local internalselection = 0
local range = 0
local currentrange = 0
local ypos = 1
local fuel
local fuelava
local counter = 1
local sandcounter=0
local cobblecounter=0

--Some draw functions to get us started
local function printCentered(str, ypos)
  term.setCursorPos(w/2 - #str/2, ypos)
  term.write(str)
end

local function printFarLeft(str, ypos)
  term.setCursorPos(1, ypos)
  term.write(str)
end

local function printLeft(str, ypos)
  term.setCursorPos(5, ypos)
  term.write(str)
end

local function printLeft2(str, ypos)
  term.setCursorPos(10, ypos)
  term.write(str)
end

local function printRight(str, ypos)
  term.setCursorPos(w - 15, ypos)
  term.write(str)
end

local function printRight2(str, ypos)
  term.setCursorPos(w - 25, ypos)
  term.write(str)
end

local function printFarRight(str, ypos)
  term.setCursorPos(w - #str, ypos)
  term.write(str)
end

function drawHeader()
	printCentered("Turtle Bridge Builder", 1)
	printCentered(string.rep("-", w+1), 2)

-- print fuel level
	fuel = turtle.getFuelLevel()
	printFarLeft("Fuel " ,3)
	print(fuel)

-- print avilable fuel
	fuelava = turtle.getItemCount(16)
	printFarLeft("Fuel Available " ,5)
	print(fuelava)

-- print avilable fuel
	sandcounter = turtle.getItemCount(1) + turtle.getItemCount(2) + turtle.getItemCount(3) + turtle.getItemCount(4) + turtle.getItemCount(5) + turtle.getItemCount(6) + turtle.getItemCount(7) + turtle.getItemCount(8)
	printRight("Sand left "..tostring(sandcounter),3)

-- print avilable fuel
	cobblecounter = turtle.getItemCount(9) + turtle.getItemCount(10) + turtle.getItemCount(11) + turtle.getItemCount(12)
	printRight("Cobble left "..tostring(cobblecounter),4)

-- Print Range
	printRight("Range Left "..tostring(range),5)
end

function drawMainMenu()
	printLeft2("1. Forward", 7)
	printRight("5. Up", 7)

	printLeft2("2. Backward", 8)
	printRight("6. Down", 8)

	printLeft2("3. Left", 9)
	printRight("7. Start bridge", 9)

	printLeft2("4. Right", 10)
	printRight("8. Quit", 10)

	printLeft2("Selection: ", 12)
	selection = tonumber(read())
end

function forward()
	term.clear()
	term.setCursorPos(1,1)
	internalselection=0
	drawHeader()

	printLeft("Forward", 7)
	printLeft("-------", 8)
	printLeft("1. Forward 1", 9)
	printRight("3. Main Menu", 9)
	printLeft("2. Forward range", 10)

	printLeft("Selection: ", 12)
	internalselection = tonumber(read())

	if internalselection==1 then
		turtle.forward()
		term.clear()
		term.setCursorPos(1,1)
	end

	if internalselection==2 then
		term.clear()
		term.setCursorPos(1,1)

		drawHeader()

		printLeft("Forward Range", 7)
		printLeft("-------------", 8)
		printLeft("How far: ", 9)
		currentrange = 0
		range = tonumber(read())

		repeat
			term.clear()
			term.setCursorPos(1,1)
			drawHeader()

			turtle.forward()
			currentrange = currentrange + 1
		until currentrange == range

		range=0
	end
end

function backward()
	term.clear()
	term.setCursorPos(1,1)
		internalselection=0
	drawHeader()

	printLeft("Backward", 7)
	printLeft("--------", 8)
	printLeft("1. Backward 1", 9)
	printRight("3. Main Menu", 9)
	printLeft("2. Backward range", 10)

	printLeft("Selection: ", 12)
	internalselection = tonumber(read())

	if internalselection==1 then
		turtle.back()
		term.clear()
		term.setCursorPos(1,1)
	end

	if internalselection==2 then
		term.clear()
		term.setCursorPos(1,1)

		drawHeader()

		printLeft("Backward Range", 7)
		printLeft("-------------", 8)
		printLeft("How far: ", 9)
		currentrange = 0
		range = tonumber(read())

		repeat
			term.clear()
			term.setCursorPos(1,1)
			drawHeader()

			turtle.back()
			currentrange = currentrange + 1
		until currentrange == range

		range=0
	end

	if internalselection==3 then
		term.clear()
		term.setCursorPos(1,1)
		internalselection=0
		selection=0
		main()
	end
end

function up()
	term.clear()
	term.setCursorPos(1,1)
	internalselection=0
	drawHeader()

	printLeft("Up", 7)
	printLeft("--", 8)
	printLeft("1. Up 1", 9)
	printRight("3. Main Menu", 9)
	printLeft("2. Up range", 10)

	printLeft("Selection: ", 12)
	internalselection = tonumber(read())

	if internalselection==1 then
		turtle.up()
		term.clear()
		term.setCursorPos(1,1)
	end

	if internalselection==2 then
		term.clear()
		term.setCursorPos(1,1)

		drawHeader()

		printLeft("Up Range", 7)
		printLeft("--------", 8)
		printLeft("How far: ", 9)
		currentrange = 0
		range = tonumber(read())

		repeat
			term.clear()
			term.setCursorPos(1,1)
			drawHeader()

			turtle.up()
			currentrange = currentrange + 1
		until currentrange == range

		range=0
	end

	if internalselection==3 then
		term.clear()
		term.setCursorPos(1,1)
		internalselection=0
		selection=0
		main()
	end
end

function down()
	term.clear()
	term.setCursorPos(1,1)
	internalselection=0
	drawHeader()

	printLeft("Down", 7)
	printLeft("----", 8)
	printLeft("1. Down 1", 9)
	printRight("3. Main Menu", 9)
	printLeft("2. Down range", 10)

	printLeft("Selection: ", 12)
	internalselection = tonumber(read())

	if internalselection==1 then
		turtle.down()
		term.clear()
		term.setCursorPos(1,1)
	end

	if internalselection==2 then
		term.clear()
		term.setCursorPos(1,1)

		drawHeader()

		printLeft("Down Range", 7)
		printLeft("----------", 8)
		printLeft("How far: ", 9)
		currentrange = 0
		range = tonumber(read())

		repeat
			term.clear()
			term.setCursorPos(1,1)
			drawHeader()

			turtle.down()
			currentrange = currentrange + 1
		until currentrange == range

		range=0
	end

	if internalselection==3 then
		term.clear()
		term.setCursorPos(1,1)
		internalselection=0
		selection=0
		main()
	end
end

function startbridge()
	term.clear()
	term.setCursorPos(1,1)
	internalselection=0
	drawHeader()

	printLeft("Starting Bridge", 7)
	printLeft("---------------", 8)
	printLeft("1. Bridge by 1", 9)
	printRight("3. Main Menu", 9)
	printLeft("2. Bridge range", 10)

	printLeft("Selection: ", 12)
	internalselection = tonumber(read())

	if internalselection==1 then
		turtle.forward()
		while true do

			turtle.select(1)
			turtle.placeDown()

			turtle.select(1)
			if turtle.compareTo(13) then
				turtle.select(8)
				turtle.transferTo(1, 64)
				turtle.select(7)
				turtle.transferTo(1, 64)
				turtle.select(6)
				turtle.transferTo(1, 64)
				turtle.select(5)
				turtle.transferTo(1, 64)
				turtle.select(4)
				turtle.transferTo(1, 64)
				turtle.select(3)
				turtle.transferTo(1, 64)
				turtle.select(2)
				turtle.transferTo(1, 64)
			end

			turtle.select(9)
			if turtle.compareTo(13) then
				turtle.select(12)
				turtle.transferTo(9, 64)
				turtle.select(11)
				turtle.transferTo(9, 64)
				turtle.select(10)
				turtle.transferTo(9, 64)
			end

			if turtle.detectDown() then
				turtle.digDown()
				turtle.select(9)
				turtle.placeDown()
				break
			end
		end

		term.clear()
		term.setCursorPos(1,1)
	end

	if internalselection==2 then
		term.clear()
		term.setCursorPos(1,1)

		drawHeader()

		printLeft("Bridge Length", 7)
		printLeft("----------", 8)
		printLeft("How far: ", 9)
		currentrange = 0
		range = tonumber(read())

		repeat
			term.clear()
			term.setCursorPos(1,1)
			drawHeader()
			turtle.forward()
			while true do
				turtle.select(1)
				turtle.placeDown()

				turtle.select(1)
				if turtle.compareTo(13) then
					turtle.select(8)
					turtle.transferTo(1, 64)
					turtle.select(7)
					turtle.transferTo(1, 64)
					turtle.select(6)
					turtle.transferTo(1, 64)
					turtle.select(5)
					turtle.transferTo(1, 64)
					turtle.select(4)
					turtle.transferTo(1, 64)
					turtle.select(3)
					turtle.transferTo(1, 64)
					turtle.select(2)
					turtle.transferTo(1, 64)
				end

				turtle.select(9)
				if turtle.compareTo(13) then
					turtle.select(12)
					turtle.transferTo(9, 64)
					turtle.select(11)
					turtle.transferTo(9, 64)
					turtle.select(10)
					turtle.transferTo(9, 64)
				end

				if turtle.detectDown() then
					turtle.digDown()
					turtle.select(9)
					turtle.placeDown()
					break
				end
			end
			currentrange = currentrange + 1
		until currentrange == range
	end

	if internalselection==3 then
		term.clear()
		term.setCursorPos(1,1)
		internalselection=0
		selection=0
		main()
	end
end

function main()
--PROGRAM START
term.clear()
term.setCursorPos(1,1)

	while true do
		drawHeader()
		drawMainMenu()

		if fuel < 5 then
			turtle.select(16)
			turtle.refuel(1)
			turtle.select(1)
		end

		if selection==1 then
			forward()
		end

		if selection==2 then
			backward()
		end

		if selection==3 then
			turtle.turnLeft()
			term.clear()
			term.setCursorPos(1,1)
		end

		if selection==4 then
			turtle.turnRight()
			term.clear()
			term.setCursorPos(1,1)
		end

		if selection==5 then
			up()
		end

		if selection==6 then
			down()
		end

		if selection==7 then
			startbridge()
		end

		if selection==8 then
			term.clear()
			term.setCursorPos(1,1)
			break
		end

	end
end

main()