What basic equipment is needed for for wedding photography?

I would consider myself a fairly serious amateur photographer and have mainly shot landscapes. My friend saw some photos that I had taken and asked if I could take her wedding pictures. I told her that I was in no way a professional and that I could not guarantee the "perfect" wedding portraits. She said that she knew that and wanted me to take them anyway. Now I am wondering what type of lighting and lenses would best suit wedding photography. I can probably think of some things but I just thought I would ask so that I don't miss anything that would make my pictures better than they would be otherwise. Thank you for your help.