Use random theme

Question

I am thinking about random theme from 2-3 selected themes, which is shown for new user and saved to cookies or ip, to not show other theme for him again. Just show random themes for new users, so I could see witch theme is better performing.

Is it possible to do this kind of a plugin or create a function for a wordpress? I found that plugin http://wordpress.org/extend/plugins/wordpress-ab-theme-split-tests/ but it seems not to be working properly and I need much simpler solution with possibility to choose few themes to spin from. Please help guys.

Answer 1

I'll preface this by saying I don't think it's the best of ideas, but in the interest of answering the question...

The general idea is to filter template, option_template, and option_stylesheet in a plugin and return your desired template slug. The rest of the code is just setting and reading the cookie.

<?php
/**
 * Plugin Name: WPD Theme Switcher
 */

class WPD_Theme_Switcher {

    private $themes = array(
        'twentythirteen',
        'twentyfourteen',
        'twentyfifteen'
    );
    private $current_theme = '';
    private $cookie = 'wpd_theme_switcher_cookie';

    function __construct() {

        if( empty( $this->current_theme ) && !isset( $_COOKIE[ $this->cookie ] ) ) {
            $this->current_theme = $this->themes[ array_rand( $this->themes ) ];
            setcookie( $this->cookie, $this->current_theme, time() + (10 * 365 * 24 * 60 * 60) );
        } else {
            $this->current_theme = $_COOKIE[ $this->cookie ];
        }

        // don't switch themes for admin requests
        if( ! is_admin() ){
            add_filter( 'template', array( $this, 'theme_switcher' ) );
            add_filter( 'option_template', array( $this, 'theme_switcher' ) );
            add_filter( 'option_stylesheet', array( $this, 'theme_switcher' ) );
        }

    }

    function theme_switcher(){
        return $this->current_theme;
    }

}
new WPD_Theme_Switcher();