How to validate form when the forms are inserted using ng-include

I have 3 different form pages which are inserted using ng-include into DOM within a bootstrap modal window. What is the best way to do validation in every form and do a complete form submit(for all the 3 forms) in scenario like this?

HTML

<div ng-switch on="page">
    <div ng-switch-when="Games">
        <div ng-include="'Games.html'"></div>
    </div>  
    <div ng-switch-when="Music">
        <div ng-include="'Music.html'"></div>
    </div>
    <div ng-switch-when="Videos">
        <div ng-include="'Videos.html'"></div>
    </div>
</div>

Demo : http://plnkr.co/edit/D1tMRpxVzn51g18Adnp8?p=preview