simpleminer

function refuel()
	if turtle.getFuelLevel() < 10 then
		turtle.select(1)
		turtle.refuel(1)
	end
end

turtle.select(1)
while turtle.getItemCount() < 16 do
	turtle.suckDown(16 - turtle.getItemCount())
end

refuel()

turtle.forward()
while turtle.detectUp() do

end
turtle.up()

while true do
	refuel()

	turtle.forward()
	a, b = turtle.inspect()
	if a then
		if not (b.name == "ComputerCraft:CC-Turtle") then
			break
		end
	end
end

turtle.digUp()
leftWay = turtle.detectDown()
if leftWay then
	turtle.digDown()
	turtle.turnLeft()
else
	turtle.dig()
	turtle.forward()
	turtle.digUp()
	turtle.turnRight()
end

for i=1, 100 do
	refuel()
	while not turtle.forward() do
		turtle.dig()
	end
	while turtle.detectUp() do turtle.digUp() end
	while turtle.detectDown() do turtle.digDown() end
end

turtle.turnLeft()
turtle.turnLeft()

turtle.up()

for i=1, 100 do
	refuel()
	while not turtle.forward() do
		a, b = turtle.inspect()
		if a then
			if b.name == "minecraft:gravel" then
				turtle.dig()
			end
		end
	end
end

if leftWay then
	turtle.turnRight()
else
	turtle.turnLeft()
end

while true do
	refuel()
	turtle.forward()
	a, b = turtle.inspect()
	if a then
		if b.name == "minecraft:planks" then
			break
		end
	end
end

for i=1, 2 do
	while not turtle.down() do
	end
end

turtle.turnLeft()
for v=1, 16 do
	turtle.select(v)
	item = turtle.getItemDetail()
	if item and item.name == "minecraft:coal" then
		turtle.dropDown()
	else
		turtle.drop()
	end
end

turtle.turnLeft()

os.reboot()