stripMine

local SLOT_COUNT = 16

local minecount = 0

local args = { ... }
if #args == 0 then
    print("Usage:stripmine <tunnel length> <number of tunnels>")
    error()
end

local length = args[1]
local tunnels = 1
if #args == 2 then
    tunnels = args[2]
end

function turnAround()
    turtle.turnRight()
    turtle.turnRight()
end

function getItemIndex(itemName)
    for slot = 1, SLOT_COUNT, 1 do
        local item = turtle.getItemDetail(slot)
        if(item ~= nil) then
            if(item["name"] == itemName) then
                return slot
            end
        end
    end
end

function checkFuel()
    while(turtle.getFuelLevel() < 500) do
        print("Refuelling...")
        fuelIndex = getItemIndex("minecraft:coal")
        if(fuelIndex ~= nil) then
            turtle.select(fuelIndex)
            turtle.refuel()
            print("Fuel level: "..turtle.getFuelLevel())
        end
    end
end

function storeInventory()
    if getItemIndex("enderstorage:ender_storage") then
        chestIndex = getItemIndex("enderstorage:ender_storage")
        turtle.select(chestIndex)
        turtle.placeUp()
        for slot = 1, SLOT_COUNT do
            local item = turtle.getItemDetail(slot)
            turtle.select(slot)
            if(item ~= nil) then
                local itemname = item["name"]
                if(itemname ~= "minecraft:torch" and itemname ~= "minecraft:coal") then
                    turtle.dropUp()
                end
            end
        end
        turtle.digUp()
    end
end

function digAndMove()
    while turtle.detect() do
        turtle.dig()
    end
    turtle.forward()
    turtle.digDown()
    turtle.digUp()
    minecount = minecount + 1
    if(minecount == 30) then
        print("Storing inventory")
        storeInventory()
        minecount = 0
    end
end

function placeTorch()
    if getItemIndex("minecraft:torch") then
        local torchIndex = getItemIndex("minecraft:torch")
        turnAround()
        turtle.select(torchIndex)
        turtle.down()
        turtle.place()
        turtle.up()
        turnAround()
    end
end

function nextTunnel()
    turtle.turnLeft()
    for i = 1, 4 do
        digAndMove()
        turtle.digUp()
    end
    turtle.turnRight()
end

function digTunnel()
    local tunnelsteps = 1
    for i = 1, length do
        digAndMove()
        if tunnelsteps % 7 == 0 then
            placeTorch()
            tunnelsteps = 0
        end
        tunnelsteps = tunnelsteps + 1
    end
    turtle.turnRight()
    digAndMove()
    turtle.turnRight()
    for i = 1, length do
        digAndMove()
    end

    --Return to starting position
    turtle.turnRight()
    turtle.forward()
    turtle.turnRight()
end

for i = 1, tunnels do
    digTunnel()
    nextTunnel()
    checkFuel()
end