CarlosIsLazy

rednet.open("right")

local function tryDigDown()
    if turtle.digDown() then
        return true
    end
    return false
end

local function tryDown()
    if turtle.down() then
        print("Moving down")
        return true
    else
        if tryDigDown() then
            print("Moving down")
            turtle.down()
            return true
        end
    end
    print("Can't dig down")
    return false
end

local function start()
    x = 0
    while tryDown() do
        x = x + 1
        print("Dug to level: "..x)
    end
    print("Cannot dig further. Bedrock likely reached")
    print("Returning to surface")
    while x > 0 do
        if turtle.up() then
            x = x - 1
        else
            sleep(1)
        end
    end
    print("Setting the next position")
    turtle.forward()
end

local id, msg, dist = rednet.receive()
if msg == "excavate" then
    start()
end