Matas Tunnel Bore

local layerPairs = nil

local maxLayer = 0

local inPosition = false

function dropItems()
     for x = 2, 16 do
         turtle.select(x)
         turtle.drop(64)
     end
end

function checkCoal()
    bendzoKiekis = turtle.getFuelLevel()

    if bendzoKiekis==0 then
        turtle.select(1)
        while not turtle.refuel(1) do
            print('out of fuel')
            sleep(1)
        end
    end


end
function moveForward(force)
     checkCoal()

    if force == true then
        while turtle.detect() do
            turtle.dig()
        end
    end

     return turtle.forward()
end

function moveUp(force)
    checkCoal()

    if force == true then
        while turtle.detectUp() do
            turtle.digUp()
        end
    end

    return turtle.up()
end

function moveDown(force)
    checkCoal()

    if force == true then
        while turtle.detectDown() do
            turtle.digDown()
        end
    end

    return turtle.down()
end

function digForward()
    turtle.dig()
    moveForward(true)
end

function digUp()
    turtle.digUp()
    moveUp(true)
end

function digDown()
    turtle.digDown()
    moveDown(true)
end

function digTwoColumns()
    for y = 1, 3 do
        digUp()
    end

    digForward()

    for y = 1, 3 do
        digDown()
    end
end

function digFourColumns()
    digTwoColumns()
    digForward()
    digTwoColumns()
end

function digTwoLayers()
    digForward()
    turtle.turnRight()

    digFourColumns()

    turtle.turnLeft()
    digForward()
    turtle.turnLeft()

    digFourColumns()

    turtle.turnRight()

    maxLayer = maxLayer + 2
end

function reachMaxLayer()
    while moveForward(false) do
        maxLayer = maxLayer + 1
    end

    inPosition = true
end

function goMining()
    if inPosition == true then
        inPosition = false
    else
        for i = 1, maxLayer do
            moveForward(true)
        end
    end

    for i = 1, layerPairs do
        digTwoLayers()
    end
end

function goTakeCoal()
    moveUp(true)
    turtle.select(1)

    hasFuel = turtle.getItemCount(1)
    needCount = 64 - hasFuel

    while not turtle.suck(needCount) do
        print('please put fuel in the chest')
        sleep(1)
    end

    moveDown(true)
end

function goStoreItems()
    turtle.turnRight()
    turtle.turnRight()

    for i = 1, maxLayer do
        moveForward(true)
    end

    dropItems()

    goTakeCoal()

    turtle.turnRight()
    turtle.turnRight()
end

print('How many layer pairs should I dig per session? ')
local input = nil

while true do
    input = tonumber(read())

    if (input == nil) or (math.floor(input) ~= input) then
        print('input should be an integer.')
    else
        layerPairs = input
        term.clear()
        break
    end
end

goStoreItems()
reachMaxLayer()

while true do
    goMining()
    goStoreItems()
end