harvest

local oldf = turtle.forward
function turtle.forward(...)
    local tArgs = {...}
    local x, y = oldf(tArgs)
    if not x and not turtle.detect() then
        repeat
            turtle.attack()
            x, y = oldf(tArgs)
        until x
    end
    return x, y
end

if turtle.getFuelLevel() < 8 then
    turtle.select(16)
    turtle.refuel(1)
    turtle.select(1)
end
turtle.turnLeft(); turtle.turnLeft()
turtle.forward(); turtle.up()
for i = 1, 6 do
    turtle.forward()
end
turtle.turnLeft()
for i = 1, 3 do
    turtle.forward()
end
turtle.turnRight()
turtle.forward()
for i = 1, 8 do
    for _ = 1, 8 do
        if turtle.getFuelLevel() < 8 then
            turtle.select(16)
            turtle.refuel(1)
            turtle.select(1)
        end
        local _, t = turtle.inspectDown()
        if t["state"] then
            if t["state"]["age"] == 3 then
                turtle.digDown()
                turtle.placeDown()
            end
        end
        turtle.forward()
    end
    if i % 2 == 0 then
        turtle.turnLeft()
    else
        turtle.turnRight()
    end
    turtle.forward()
    if i % 2 == 0 then
        turtle.turnLeft()
    else
        turtle.turnRight()
    end
    turtle.forward()
end
turtle.turnLeft(); turtle.turnLeft()
for i = 1, 4 do
    turtle.forward()
end
turtle.turnRight()
for i = 1, 5 do
    turtle.forward()
end
turtle.turnLeft()
for i = 1, 5 do
    turtle.forward()
end
turtle.down()
turtle.forward()
for i = 1, 15 do
    turtle.select(i)
    turtle.drop(64)
end
turtle.select(1)