I have developed a game on android using native coding. However I am being asked to port it to ios. 

So I thought that I should bite the bullet and recode it in unity so I can go cross platform. 

I am just upset that I have to recode everything in unity. Is there any other way or tool that at least will make me use half of my code or so thing? 
Basically what would you do. 

Ps:I don't even know unity but I heard learning it is easy