Turtle Miner

function dig()
 while turtle.detect() do
  turtle.dig()
 end
 os.sleep(0.5)
 turtle.forward()
 while turtle.detectDown() or turtle.detectUp() do
  turtle.digUp()
  turtle.digDown()
 end
end

function onelayer()
 dig()
 turtle.turnLeft()
 dig()
 turtle.turnRight()
 turtle.turnRight()
 turtle.forward()
 dig()
 turtle.turnLeft()
 turtle.turnLeft()
 turtle.forward()
 turtle.turnRight()
end

function placeTorch()
 turtle.turnLeft()
 turtle.forward()
 turtle.select(16)
 turtle.placeUp()
 turtle.turnRight()
 turtle.turnRight()
 turtle.forward()
 turtle.turnLeft()
 turtle.select(1)
end

function drop()
 for i = 1, 15 do
  turtle.select(i)
  turtle.dropDown(64)
 end
end

run = 0

b = 0

m = 0

tunnel = 1

term.clear()
term.setCursorPos(1,1)
term.write("Length (Max = 50): ")
run = read()
term.write("Number of tunnels: ")
tunnel = read()

for i = 1, run do

 m = run * 5 * tunnel * 98
 if turtle.getFuelLevel() <= m then
  b = i - 1
 turtle.turnLeft()
 turtle.turnLeft()
 for i = 1, b do
  turtle.forward()
 end
 turtle.down()
 drop()
 turtle.up()
 turtle.turnRight()
 turtle.turnRight()
  m = m / 80
  m = m + 1
  turtle.turnLeft()
  turtle.select(1)
  turtle.suck(m)
  turtle.refuel(m)
  turtle.turnRight()
  b = i - 1
 for i = 1, b do
  turtle.forward()
 end
 end

 if turtle.getItemSpace(15) <= 63 then
  b = i - 1
 turtle.turnLeft()
 turtle.turnLeft()
 for i = 1, b do
  turtle.forward()
 end
 turtle.down()
 drop()
 turtle.up()
 turtle.turnRight()
 turtle.turnRight()
  b = i - 1
 for i = 1, b do
  turtle.forward()
 end
 end

 if turtle.getItemCount(16) <= 1 then
  b = i - 1
 turtle.turnLeft()
 turtle.turnLeft()
 for i = 1, b do
  turtle.forward()
 end
 turtle.down()
 drop()
 turtle.up()
 turtle.turnRight()
 turtle.turnRight()
  turtle.turnRight()
  turtle.select(16)
  turtle.suck(63)
  turtle.turnLeft()
  b = i - 1
 for i = 1, b do
  turtle.forward()
 end
 turtle.select(1)
 end

 turtle.select(1)
 onelayer()

 if i % 4 == 0 then
  placeTorch()
 end

end

if run % 4 == 3 then
 turtle.select(16)
 turtle.placeUp()
 turtle.select(1)
end

turtle.back()
turtle.turnRight()
turtle.forward()
for i = 1, 3 do
 onelayer()
end
placeTorch()
turtle.back()
turtle.turnRight()
turtle.forward()

local h = 0
h = run - 3
for i = 1, h do
 if i % 4 == 0 then
  placeTorch()
 end

 b = i + 1
 if turtle.getItemSpace(15) <= 63 then
  for i = 1, b - 1 do
   turtle.back()
  end
  turtle.turnRight()
  for i = 1, 3 do
   turtle.forward()
  end
  turtle.turnLeft()
  for i = 1, run - 1 do
   turtle.forward()
  end
  turtle.down()
  drop()
  turtle.up()
  turtle.turnRight()
  turtle.turnRight()
  for i = 1, run - 1 do
   turtle.forward()
  end
  turtle.turnRight()
  for i = 1, 3 do
   turtle.forward()
  end
  turtle.turnRight()
  for i = 1, b do
   turtle.forward()
  end
 end

 if turtle.getItemCount(16) <= 1 then
  for i = 1, b - 1 do
   turtle.back()
  end
  turtle.turnRight()
  for i = 1, 3 do
   turtle.forward()
  end
  turtle.turnLeft()
  for i = 1, run - 1 do
   turtle.forward()
  end
  turtle.down()
  drop()
  turtle.up()
  turtle.turnLeft()
  turtle.select(16)
  turtle.suck(63)
  turtle.turnLeft()
  for i = 1, run - 1 do
   turtle.forward()
  end
  turtle.turnRight()
  for i = 1, 3 do
   turtle.forward()
  end
  turtle.turnRight()
  for i = 1, b do
   turtle.forward()
  end
  turtle.select(1)
 end

 turtle.select(1)
 onelayer()

end

for  i = 1, h do
 turtle.back()
end
turtle.turnRight()
for i = 1, 3 do
 turtle.forward()
end
turtle.turnLeft()
for i = 1, run do
 turtle.forward()
end
turtle.down()
drop()
turtle.up()
turtle.turnLeft()
turtle.turnLeft()