local status = "Idle"
local cycles = 0
local cyclesDone = 0

-- Continuiesly updates terminal to inform user of status
function uiLoop()
	while true do
		term.clear()
		term.setCursorPos(1, 1)
		print("AutoMiner - tedski999, 2019")
		print("===========================")
		print("")
		print("Status: " .. status)
		print("Fuel:   " .. turtle.getFuelLevel())
		print("Cycles: " .. cyclesDone .. "/" .. cycles)
		sleep(0.5)
	end
end

-- Main loop controlling the turtles actions
function minerLoop()
	for i = 1, cycles do
		checkFuelSufficient()
		mineSlice()
		mineCorridor()
		cyclesDone = cyclesDone + 1
	end
	status = "Done!"
end

-- Refuel if needed to ... movements required per cycle: 34
function checkFuelSufficient()
	while turtle.getFuelLevel() < 35 do
		turtle.select(16)
		if turtle.refuel(0) then
			turtle.refuel(1)
		else
			status = "Out of Fuel!"
			while not turtle.refuel(0) do
				sleep(0.5)
			end
		end
	end
end

-- Mines a strip on either side of the main corridor
function mineSlice()
	status = "Mining slice..."
	turtle.dig()
	attemptForward()
	turtle.turnLeft()
	repeatMineForward(6)
	endLeftStrip()
	repeatMineForward(13)
	endRightStrip()
	repeatMineForward(6)
	turtle.digUp()
	attemptForward()
	turtle.digUp()
	turtle.turnRight()
end

-- Continue main corridor
function mineCorridor()
	status = "Continuing main corridor..."
	mine3YForward()
	turtle.turnRight()
	mine3YForward()
	turtle.turnLeft()
	mine3YForward()
	turtle.turnLeft()
	mine3YForward()
	turtle.turnRight()
	turtle.turnRight()
	placeTorchForward()
	turtle.turnLeft()
end

-- Place a torch and turn around at the end of the left side stip
function endLeftStrip()
	turtle.dig()
	placeTorchForward()
	turtle.digDown()
	attemptDown()
	turtle.dig()
	turtle.turnLeft()
	turtle.turnLeft()
end

-- Place a torch and turn around at the end of the right side stip
function endRightStrip()
	turtle.dig()
	turtle.digUp()
	attemptUp()
	turtle.dig()
	placeTorchForward()
	turtle.turnLeft()
	turtle.turnLeft()
end

-- Mines forward i times
function repeatMineForward(i)
	for i = 1, i do
		turtle.dig()
		attemptForward()
	end
end

-- Mines a 1x3x1 column in front and moves into it
function mine3YForward()
	turtle.dig()
	attemptForward()
	turtle.digUp()
	turtle.digDown()
end

-- Places a torch directly in front
function placeTorchForward()
	if turtle.getItemCount(15) < 1 then
		status = "Out of Torches!"
		while turtle.getItemCount(15) < 1 do
			sleep(0.5)
		end
	end
	turtle.select(15)
	turtle.place()
end

-- Gravel/Sand proof movement
function attemptForward()
	while not turtle.forward() do
		turtle.dig()
	end
end

-- Gravel/Sand proof movement
function attemptUp()
	while not turtle.up() do
		turtle.digUp()
	end
end

-- Gravel/Sand proof movement
function attemptDown()
	while not turtle.down() do
		turtle.digDown()
	end
end

---- START POINT ----

-- Initialization
while true do
	term.clear()
	term.setCursorPos(1, 1)
	term.write("Enter number of cycles to be done: ")
	cycles = tonumber(read())
	if cycles == nil then
		print("Sorry, that's not a number!")
	elseif cycles > 20 then
		print("Sorry, max of 20 cycles!")
	elseif cycles < 1 then
		print("Sorry, input must be greater than 0!")
	else
		break
	end
	sleep(1)
end

-- Start main loop
parallel.waitForAny(uiLoop, minerLoop)

-- End
term.clear()
term.setCursorPos(1, 1)
print("Completed " .. cycles .. " cycles.")