profile-rel-links.php

<?php
/**
 * @package profile-rel-links
 * @version 1.0
 * @requires php >= 5.3
 */
/*
Plugin Name: Profile rel= links
Plugin URI: http://github.com/blumenthals/profile-rel-links
Description: Adds rel= links to profiles for matching up with Twitter and Google profiles
Author: Aria Stewart <aria@blumenthals.com>
Version: 1.0
Author URI: http://blumenthals.com/
*/

add_filter('user_contactmethods', function($contactmethods) {
	$contactmethods['gprofile'] = 'Google Profile or Google+';
	$contactmethods['twitter'] = 'Twitter';
	return $contactmethods;
});

if(is_admin()) {
	add_action('admin_init', function() {
		add_option('prl_intercept_links', true, null, true);
		add_option('prl_add_to_author_page', true, null, true);
		add_settings_section('prl_main', 'Main Settings', function() { }, 'profile-rel-links');
		register_setting( 'profile-rel-links', 'prl_intercept_links' );
		register_setting( 'profile-rel-links', 'prl_add_to_author_page' );
		add_settings_field('prl_intercept_links', 'Intercept Links and add "rel="?', function() {
			$opt = get_option('prl_intercept_links');
			?> <input id='prl_intercept_links' name='prl_intercept_links' type='checkbox' <?php checked(1, $opt); ?> value='1' /> <?php
		}, 'profile-rel-links', 'prl_main');
		add_settings_field('prl_add_to_author_page', 'Add profile information to the Author Archive', function() {
			$opt = get_option('prl_add_to_author_page');
			?> <input id='prl_add_to_author_page' name='prl_add_to_author_page' type='checkbox' <?php checked(1, $opt); ?> value='1' /> <?php
		}, 'profile-rel-links', 'prl_main');
	});
	add_action('admin_menu', function() {
		add_options_page('rel= Links', 'Profile rel= Links', 'manage_options', 'profile-rel-links', function() {
			if (!current_user_can('manage_options'))  {
				wp_die( __('You do not have sufficient permissions to access this page.') );
			}
			?>
			<div class="wrap">
			<h2>Profile rel= links</h2>
			<form method="post" action="options.php"> 
			<?php 

				settings_fields('profile-rel-links');
				do_settings_sections('profile-rel-links');
			?>
			<p class="submit">
			<input type="submit" class="button-primary" value="<?php _e('Save Changes') ?>" />
			</p>
			</form>
			</div>
			<?php
		});
	});
}


add_action('init', function() {
	if(get_option('prl_intercept_links')) add_action('wp', function() {

		global $wp_rewrite;
		$rules = array();
		foreach($wp_rewrite->rules as $rule => $val) {
			if(preg_match('/^author/', $rule)) $rules[] = str_replace(array('(', '$'), array('(?:', ''), $rule);
		}
		ob_start(function($content) use ($rules) {
			foreach($rules as $rule) {
				$content = preg_replace('#(<a[^>]*)(href=[^>]*'.$rule.')#', '\1 rel="author" \2\3', $content);
			}
			return $content;
		});
	});

	if(get_option('prl_add_to_author_page')) add_action('loop_start', function($q) {
		static $seen = false;
		if(!$seen and $q->is_author()) {
			$authorID = $q->query_vars['author'];
			$methods = _wp_get_user_contactmethods($authorID);
			echo "<div class='author_contactinfo'>";
			foreach($methods as $k => $v) {
				$val = get_user_meta($authorID, $k, true);
				if(preg_match("/^\w+:/", $val)) {
					print("<a rel='me' href='$val'>$v</a><br />");
				} else {
					if($val) print("$v: $val<br />");
				}
			}
			echo "</div>";
			$seen = true;
		}
	});
});

?>