Mining-turtle (Stripmining) V.1.7 Final (XenoEdit3)

    --This code is developed by me (onix331) and modified by Xenomurks and is availiable under the GNU General Public License (Version 3)
    --See http://opensource.org/licenses/GPL-3.0
    --Have fun

    shaftcount = 0--Used later in the program, usually not necessary do modify it
    space = 15--Defines the space of the turtle
    ver = 1.7--For updates
    chest = 0--If the turtle has stopped at a chest
    stop = 0--If the turtle has stopped at a chest
    direction = r

    function checkl() --To check if length is valid (>0, not a String), also transforms the string into a number
        length = tonumber(length)
        if length==nil then
            print ("Invalid number!")
            length = read()
            checkl()
        elseif length <= 0 then
            print ("Invalid number!")
            length = read()
            checkl()
        end
    end

    function checka()--To check if count is valid (>0, not a String), also transforms the string into a number
        count = tonumber(count)
        if count==nil then
            print ("Invalid number!")
            count = read()
            checka()
        elseif count <= 0 then
            print ("Invalid number!")
            count = read()
            checka()
        end
    end

    function checkr()--To check if direction is valid ((r) or (l))
        if direction=="r" then
            print ("")
        elseif direction=="l" then
            print ("")
        else
            print ("Invalid input!")
            direction = io.read()
            checkr()
        end
    end

    function checkref()--To check if refuel is valid ((r) or (l))
        if refuel=="y" then
            print ("")
        elseif refuel=="n" then
            print ("")
        else
            print ("Invalid number!")
            refuel = io.read()
            checkref()
        end
    end

    function move()--Basic movement funktion
        local debug = 8--Used to avoid gavel, sand, etc.
        for i = 1, length do
        if turtle.detect() then
            for i = 1, debug do
                turtle.dig()
            end
            turtle.forward()
        else
            turtle.forward()
        end
        if turtle.detectUp() then
            for i = 1, debug do
                turtle.digUp()
            end
        end
        end
    end

    function turnaround()--Turns the turtle at 90 degrees
        turtle.turnRight()
        turtle.turnRight()
    end

    function nextshaft()--Next shaft (right)
        turtle.turnLeft()
        turtle.dig()
        turtle.digUp()
        turtle.forward()
        turtle.dig()
        turtle.digUp()
        turtle.turnRight()
        turtle.select(16)
        turtle.placeUp()
        turtle.turnLeft()
        turtle.forward()
        turtle.dig()
        turtle.digUp()
        turtle.forward()
        turtle.digUp()
        turtle.turnRight()
    end

    function returnpoint()--Return to initial point
        if direction=="r" then
            turtle.turnRight()
            if shaftcount>=2 then
                turtle.forward()
            end
            turtle.forward()
            for i = 1, shaftcount do
                turtle.forward()
                turtle.forward()
            end
            if stop==1 then
                turtle.forward()
            end
            --turtle.turnLeft()
            for i = 1, space do
                turtle.select(i)
                turtle.drop()
            end
            turtle.select(1)
        end
        turnaround()
        if chest==1 then
            returnmining()
        end
    end

    function returnmining()--Beta-feature
        stop = 1
        chest = 0
        if direction=="r" then
            turnaround()
            for i = 1, shaftcount do
                turtle.forward()
                turtle.forward()
                turtle.forward()
            end
            turtle.turnRight()
            for i = 1, count do
                move()
                turnaround()
                move()
                move()
                turnaround()
                move()
                nextshaft()
                shaftcount = shaftcount + 1
                count = count - 1
                checkspace()
            end
        end
    end

    function checkspace()--Check for space and if necessary, return to initial point to the chest
        local spaceleft = 0
        for i = 1, space do
            if turtle.getItemSpace(i) > 10 then
                spaceleft = spaceleft + 1
            end
        end
        if spaceleft < 5 then
            chest = 1
            count = count - 1
            returnpoint()
        end
    end

    shell.run ("clear")
    print ("Strip-mining-program by onix331")
    print ("Version ", ver)

    --Start user input
    print ("Length of the single shaft(s):")
    length = read()
    checkl()

    print ("Count of the shafts:")
    count = read()
    checka()


    print ("Want to put some Torches on the Wall?")
    print ("Now? (Yes (y), No (n):")
    torch = read()
    checkref()
    if torch=="y" then
        print ("Please Put some in Slot 16")
        print ("When done, press ENTER")
        local sEvent, param = os.pullEvent("key")
        if sEvent == "key" then

        end
    end


    --Refueling, a little bit complicated
    print ("Dont forget to refuel!")
    print ("Now? (Yes (y), No (n):")
    refuel = read()
    checkref()
    if refuel=="y" then
        print ("Please insert fuel anywhere")
        print ("When done, press ENTER")
        while true do
                local sEvent, param = os.pullEvent("key")
                if sEvent == "key" then
                        if param == 28 then
                    for i = 1, space do
                        for i = 1, 64 do
                            shell.run("refuel", rafzahl)
                        end
                        turtle.select(i)
                    end
                    turtle.select(1)
                    break
                end
            end
        end
    end

    --Print user inputs
    shell.run ("clear")
    print ("Input of Length:")
    print (length)
    print ("Input of count")
    print (count)
    os.sleep(2)
    print ("3")
    os.sleep(1)
    print ("2")
    os.sleep(1)
    print ("1")
    os.sleep(1)
    print("Start!")

    --Main Program

    if direction=="r" then
        turtle.turnRight()
        for i = 1, count do
            move()
            turnaround()
            move()
            move()
            turnaround()
            move()
            nextshaft()
            shaftcount = shaftcount + 1
            count = count - 1
            checkspace()
        end
    end
    returnpoint()
    print ("Done!")