Is there a story or a mentioning about masturbation in the Buddhist teachings?

1. Is masturbation wrong? In what exact way is it wrong? I just need to know if the act of masturbation is wrong. This may include watching nudity while masturbating. Even though it's an addiction, I was wandering if it hold more or any negative karma than another general addiction, like addiction to food. I just need your opinion in this backed up by references to the teachings. 2. Is the act of masturbation a barrier towards mental concentration or samadhi? Will I have more mindfulness and concentration if I get rid of this addiction? I'm talking about the samadhi gained through annapanasati. 3. In what way can I get rid of this addiction if it is leading me away from the path? Please give instructions to one who is somewhat deeply ingrained in it. I am not here to discuss about an 'embarrassing' topic, rather a plausible problem (affirmed by many Buddhists) that a majority of people in the western world have. I am also here to see if my addiction can be a cause for any other negative habits, like many Buddhist say so. That being said, thank you very much for the help. I honestly will appreciate the answer you give me, since this idea have haunted and caused inner conflicts within me for the past 2 years.