For those interested in a good author on Samurai then I strongly suggest Stephen Turnbull. He's an expert in the field. Link goes to Amazon's list of his books.
BTW, the Bushido as described in Bushido Shoshinsu by Taira Shigesuke was written in the Tokugawa Shogunate where Samurai did not fight any longer. In the Sengoku (the civil war and what most of us think of as the golden days of the Samurai) there was no such code. After all, Oda used firearms after the Sohei used them against him and he saw their power on the battlefield.
As with everything, read one book on a subject and you're an expert. read ten books on that subject and you start seeing shades of grey everywhere. Read a hundred books on that said subject and you start doubting everything!