Plugin para mudar o tema de acordo com o Browser, usado para temas mobile

bbt.php

<?php

/*
Plugin Name: Browser-Based Themes
Plugin URI: http://code.kuederle.com/browserbasedthemes
Description: This plugin will serve a different theme to specific browsers.
Author: Oliver Kuederle
Author URI: http://www.kuederle.com/
Version: 1.0
*/

// Activate theme switching.
add_filter('template', 'serveBrowserBasedTheme');
add_filter('option_template', 'serveBrowserBasedTheme');
add_filter('option_stylesheet', 'serveBrowserBasedTheme');

/**
 * This is the main function of the plug-in which switches to another
 * theme based on the user agent.
 */
function serveBrowserBasedTheme($originalTheme) {
	// Check if we have a valid theme.
	$alternativeTheme = get_option("bbt_current_theme","");
	$found = false;
	foreach(get_themes() as $theme)
		if($theme["Template"] == $alternativeTheme) {
			$found = true;
			break;
		}
	if(!$found)
		return $originalTheme;
	
	// Compare user agents.
	$userAgents = explode("$|$",get_option("bbt_user_agents",""));
	foreach($userAgents as $userAgent)
		if(strlen($userAgent) > 0 && strpos($_SERVER['HTTP_USER_AGENT'], $userAgent) !== false)
			return $alternativeTheme;

	return $originalTheme;
}

// Add a configuration screen.
add_action('admin_menu','addBrowserBasedThemeMenu');

/**
 * This function adds new adminsitration menus.
 */
function addBrowserBasedThemeMenu() {
	add_plugins_page('Settings for the Browser-Based Themes Plugin', 'Browser-Based Themes Config', 'manage_options', 'browser-based-theme', 'displayBrowserBasedThemeOptions');
}

/**
 * Renders the browser-based theme options page.
 */
function displayBrowserBasedThemeOptions() {

	if (!current_user_can('manage_options'))  {
	wp_die( __('You do not have sufficient permissions to access this page.') );
	}
	
	// Get plugin options.
	$currentTheme = get_option("bbt_current_theme","Default");
	$userAgents = explode("$|$",get_option("bbt_user_agents",""));
	
	// Were the options changed?
	if(isset($_POST["bbt_submitted"]) && $_POST["bbt_submitted"] == "true") {
		// Yes. Retrieve user input.
		$currentTheme = $_POST["bbt_current_theme"];
		$userAgents = explode("\n",$_POST["bbt_user_agents"]);
		$agents = array();
		foreach($userAgents as $userAgent) {
			$agent = trim($userAgent);
			if(strlen($agent) > 0)
				$agents[] = $agent;
		}
		$userAgents = $agents;
		
		// Save to database.
		update_option("bbt_current_theme",$currentTheme);
		update_option("bbt_user_agents",implode("$|$",$userAgents));
		
		// Display success message.
		echo '<div class="updated"><p><strong>Settings have been saved.</strong></p></div>';
	}

	?>

	<div class="wrap">

	<h2>Browser-Based Themes Plugin Options</h2>

	<form method="POST" action="">
		<p>
			<label>User agent strings to look for (one per line):</label><br/>
			<textarea name="bbt_user_agents" cols="40" rows="4"><?php
				foreach($userAgents as $userAgent)
					echo htmlspecialchars($userAgent)."\n";
			?></textarea>
		</p>
		<p>
			<label>Alternative theme to be displayed:</label>
			<select name="bbt_current_theme"><?php
				$themes = get_themes();
				foreach($themes as $theme) {
					echo '<option';
					if($theme["Template"] == $currentTheme)
						echo ' selected="selected"';
					echo ' value="'.htmlspecialchars($theme["Template"]).'">'.htmlspecialchars($theme["Name"]).'</option>'."\n";
				}
			?></select>
		</p>

		<p class="submit">
		<input type="hidden" name="bbt_submitted" value="true"/>
		<input type="submit" name="Submit" class="button-primary" value="Save Changes" />
		</p>
		
	</form>
	
	<p>For a list of user agents for mobile phones, look <a href="http://en.wikipedia.org/wiki/List_of_user_agents_for_mobile_phones">here</a>.</p>

	</div>
  
	<?php

}


?>