wp_redirect_issue

<?php
/**
 * Plugin Name: Custom Theme Switcher
 * Description: Handles Mobile Theme Switching
 * Version: 1.0.1
 */

add_filter( 'template', 'custom_theme_redirect' );
add_filter( 'option_template', 'custom_theme_redirect' );
add_filter( 'option_stylesheet', 'custom_theme_redirect' );

function custom_get_subdomain() {
	$subdomain = '';
	if ( ! empty( $_SERVER['HTTP_HOST'] ) ) {
		$host_tokens = explode( '.', $_SERVER['HTTP_HOST'] );
		if ( ! empty( $host_tokens ) ) {
			return strval( $host_tokens[0] );
		}
	}
	return $subdomain;
}

function custom_theme_redirect( $theme ) {
	if ( ! is_admin() ) {
		if ( isset( $_GET['mobile'] ) ) {

			setcookie( 'mobile', true, time() + 1, '/', CUSTOM_ROOT_DOMAIN );
			setcookie( 'nomobile', false, time() -1, '/', CUSTOM_ROOT_DOMAIN );
			$_COOKIE['mobile'] = true;
			$_COOKIE['nomobile'] = false;

		}
		if ( DOMAIN_CURRENT_SITE === CUSTOM_MOBILE_DOMAIN || isset( $_COOKIE['mobile'] ) ) {
			if ( isset( $_GET['nomobile'] ) ) {

				setcookie( 'mobile', false, time() -1, '/', CUSTOM_ROOT_DOMAIN );
				setcookie( 'nomobile', true, time() + 1, '/', CUSTOM_ROOT_DOMAIN );
				$url = 'http://' . CUSTOM_MASTER_DOMAIN . $_SERVER['REQUEST_URI'];
				wp_safe_redirect( $url );
				exit;

			}
			$theme = 'custom-mobile';

		} elseif ( DOMAIN_CURRENT_SITE === CUSTOM_MASTER_DOMAIN ) {
			include_once( 'Mobile_Detect.php' );
			$detect = new Mobile_Detect;
			if ( CUSTOM_AUTO_MOBILE_REDIRECT && $detect->isMobile() && ! $detect->isTablet() ) {
				if ( ! isset( $_COOKIE['nomobile'] ) || ! $_COOKIE['nomobile'] ) {

					$url = 'http://' . CUSTOM_MOBILE_DOMAIN . $_SERVER['REQUEST_URI'];
					wp_safe_redirect( $url );
					exit;

				}
			}
		}
	}// End if().

	return $theme;

}