turtle autminer

critical_number = 100
auto_refuel = 300
critical_number = tonumber(critical_number)
rednet_update = function()
    rednet.send(computerID,"The fuel level is "..turtle.getFuelLevel())
    if turtle.getFuelLevel() <= critical_number then
        rednet.send(computerID,"Whoops... The turtle needs some extra fuel")
    end
    if turtle.getFuelLevel() >= critical_number then
        rednet.send(computerID,"There is still enough fuel")
    end
    if busy == true then
        rednet.send(computerID,"Meters left: "..length)
    end
    if busy == false then
        rednet.send(computerID,""..message)
    end
    x, y, z = gps.locate(1)
    if turtle.getFuelLevel() <= auto_refuel then
        shell.run("refuel all")
    end
    if turtle.getFuelLevel() <= critical_number then
        critical = true
    end
    rednet.send(computerID,"The gps position X: "..x)
    rednet.send(computerID,"The gps position Y: "..y)
    rednet.send(computerID,"The gps position Z: "..z)
end
if turtle.getFuelLevel() == unlimited then
    print("No support for turtles with unlimited fuel. Sorry")
    return
end
ok = true
while ok do
    print("Enter the length of the please:")
    length = tonumber(read())
    notok = false
    if type(length) == "number" then
        if length <= 5 then
            print("The length must be larger then 5")
            notok = true
        end
        if notok == false then
            print("Thanks")
            ok = false
        end
    else
        print("Please enter a number")
        return
    end
end
print("Please enter the computerID:")
computerID = tonumber(read())
if type(computerID) == "number" then
    print("Thanks, now I will send a rednet signal to the computer/turtle...")
else
    print("Please enter a number")
    return
end
rednet.open("right")
while turtle.getFuelLevel() <= auto_refuel do
    print("Not enough fuel!")
    print("Please give some fuel and press a key.")
    read()
    shell.run("refuel all")
end

busy = true
back = length
home = true
count = true
turtle.dig()
turtle.forward()
turtle.digUp()
turtle.up()
turtle.digUp()
turtle.turnRight()
turtle.dig()
turtle.forward()
turtle.digUp()
turtle.digDown()
turtle.turnRight()
turtle.turnRight()
turtle.forward()
turtle.dig()
turtle.forward()
turtle.digUp()
turtle.digDown()
length = length-1
while count do
    turtle.turnRight()
    turtle.dig()
    rednet_update()
    turtle.forward()
    turtle.digUp()
    rednet_update()
    turtle.digDown()
    turtle.turnRight()
    rednet_update()
    turtle.dig()
    turtle.forward()
    rednet_update()
    turtle.digUp()
    turtle.digDown()
    rednet_update()
    turtle.dig()
    turtle.forward()
    rednet_update()
    turtle.digUp()
    turtle.digDown()
    rednet_update()
    turtle.turnLeft()
    turtle.dig()
    rednet_update()
    turtle.forward()
    turtle.digUp()
    rednet_update()
    turtle.digDown()
    turtle.turnLeft()
    rednet_update()
    turtle.dig()
    turtle.forward()
    rednet_update()
    turtle.digUp()
    turtle.digDown()
    rednet_update()
    turtle.dig()
    turtle.forward()
    rednet_update()
    turtle.digUp()
    turtle.digDown()
    rednet_update()
    if critical == true then
        while turtle.getFuelLevel() <= critical_number do
            busy = false
            message = "Turtle stopped... Please give more fuel"
            rednet_update()
            print("Not enough fuel!")
            print("Please give some fuel and press a key.")
            read()
            shell.run("refuel all")
            critical = false
            busy = true
        end
    end
    length = length-2
    if length <= 3 then
        count = false
        print("Now I go back home")
        busy = false
        message = "Going back"
        turtle.turnLeft()
        while home do
            turtle.forward()
            back = back-1
            rednet_update()
            if back == 0 then
                turtle.turnLeft()
                turtle.forward()
                turtle.turnLeft()
                turtle.down()
                home = false
                print("Home, sweet home")
                print("Finished task")
                message = "Finished task"
                rednet_update()
                rednet.close("right")
                return
            end
        end
    end
end