nether_V1

args = {...}
distance = args[1]

function mine (direction)
    --default harvest actionset
    if direction = "up" then
        turtle.digUp()
        turtle.up()
        scan()
        turtle.down()
    elseif direction = "down" then
        turtle.digDown()
        turtle.down()
        scan()
        turtle.up()
    else
        turtle.dig()
        turtle.forward()
        turtle.scan()
    end
end

function scan ()
    --seach surrounding for desired block, and call mine() if found
    turtle.select(1)
    if turtle.compare() then
        mine()
    end
    if turtle.compareUp() then
        mine("up")
    end
    if turtle.compareDown() then
        mine("down")
    end
    turtle.turnLeft()
    if turtle.compare() then
        mine()
    end
    turtle.turnRight()
    turtle.turnRight()
    if turtle.compare() then
        mine()
    end
    turtle.turnLeft()

end

function movement (length)
    --default moveset
    for i=1, length,1 do
        turtle.dig()
        turtle.forward()
        scan()
    end
    backtrack(length)
end

function backtrack (distance)
    --return to start
    turtle.turnRight()
    turtle.turnRight()
    for i=1, length,1 do
        turtle.forward()
    end
end

function mayne (length)
    --main function

    --check for block, and refuel
    turtle.select(1)
    if turtle.getItemCount(1) = 0 then
        turtle.print("No supplied block")
        os.sleep(10)
        os.exit()
    elseif turtle.getItemCount(2) > 0 then
        turtle.select(2)
        if turtle.refuel(0) then
            turtle.refuel()
        else
            print("no new fuel provided")
        end
    end
    if turtle.getFuelLevel < (distance * 2) then
        print("fuel level too low to complete desired distance")
        os.sleep(10)
        os.exit()
    end
    --begin search
    movement(length)

end



if distance = "help" or "" then
    print("usage: nether [desired mine length]")
    print("halts if it hits an unloaded chunk, so keep within reason")
    print("block to seach for in first slot, fuel in second")
end

if not distance then
    distance = 30
end

mayne(distance)



--check for precence of block
--refuel
--mine
--move forward
--check surrounding blocks, and mine if debris
--continue until length limit