If they are both OK they you said they i thought you talking about sentences Secondly may when you said i'll be happy when you come . .. etc. it's better than you know
Both statements are tentative, with no explicit request. Both tie to the topics of present and future perfect. This may help a bit: https://www.mometrix.com/academy/present-perfect-past-perfect-and-future-perfect-verb-tenses/ but if you're just learning English, you may want to postpone this topic until you have more experience, as this topic is mostly learned by exposure. Good luck.