-- Set the size of the area to be mined
local width = 9
local height = 9

-- Function to mine forward and handle fuel
function mineForward()
    while not turtle.forward() do
        if turtle.getFuelLevel() == 0 then
            print("Out of fuel. Refuel and restart.")
            error()
        end
        turtle.refuel(1)
    end
end

-- Function to mine a full column
function mineColumn()
    for i = 1, height do
        turtle.digDown()
        mineForward()
    end
end

-- Function to move to the next column
function moveToNextColumn()
    if turtle.getFuelLevel() == 0 then
        print("Out of fuel. Refuel and restart.")
        error()
    end

    turtle.turnRight()
    turtle.digDown()
    mineForward()
    turtle.turnRight()
end

-- Main mining function
function mineArea()
    for col = 1, width do
        mineColumn()
        if col < width then
            moveToNextColumn()
        end
    end
end

-- Function to move to the next level
function moveToNextLevel()
    turtle.digDown()
    turtle.down()
end

-- Main mining process
for level = 1, height do
    mineArea()

    if level < height then
        moveToNextLevel()
    end
end