cobbler

local function findNeighbouringBlock(blockName)
    for i=1, 4 do
        local hasBlock, block = turtle.inspect();

        if block and block.name == blockName then
            return true;
        end

        turtle.turnRight();
    end

    return false;
end

local function getItemCount(itemName)
    local total = 0;

    for i=1, 16 do
        local itemDetail = turtle.getItemDetail(i);

        if itemDetail and itemDetail.name == itemName then
            total = total + turtle.getItemCount(i);
        end
    end

    return total;
end

local function mineCobble(amount)
    while getItemCount("minecraft:cobblestone") < amount do
        if turtle.detect() then
            turtle.dig();
        end
    end
end

local function depositCobble()
    while getItemCount("minecraft:cobblestone") > 0 do
        for i=1, 16 do
            turtle.drop();
        end
    end
end

local function main()
    local foundCobble = findNeighbouringBlock("minecraft:cobblestone");

    if not foundCobble then
        print("Couldn't find the cobble gen.");
        return;
    end

    local foundChest, _ = findNeighbouringBlock("minecraft:chest");
    if not foundChest then
        print("Couldn't find chest.");
        return;
    end

    turtle.turnLeft();
    turtle.turnLeft();

    local running = true;

    while running do
        mineCobble(64);
        turtle.turnRight();
        turtle.turnRight();
        depositCobble();
        turtle.turnRight();
        turtle.turnRight();
    end
end

main();