Could have caused a massive accident

This morning (10 April) just after 08:30 I was driving down Main road towards Bulders Warehouse in Tokai when suddenly a big bakkie coming from the opposite side decides to turn infront of me to turn into a pecking area. As he turned him and his colleague (passenger) decided to shout and show me hand signs. Had I not braked in time this could have been a massive accident as there were quite a few cars behind me. Instead of apologising and doing the right thing seeing as they were driving a company vehicle they decide to perform in there bakkie.