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Web.Admin/2014/wordpress/wp-includes/link-template.php

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<?php
/**
 * WordPress Link Template Functions
 *
 * @package WordPress
 * @subpackage Template
 */

/**
 * Display the permalink for the current post.
 *
 * @since 1.2.0
 * @uses apply_filters() Calls 'the_permalink' filter on the permalink string.
 */
function the_permalink() {
    echo apply_filters('the_permalink', get_permalink());
}

/**
 * Retrieve trailing slash string, if blog set for adding trailing slashes.
 *
 * Conditionally adds a trailing slash if the permalink structure has a trailing
 * slash, strips the trailing slash if not. The string is passed through the
 * 'user_trailingslashit' filter. Will remove trailing slash from string, if
 * blog is not set to have them.
 *
 * @since 2.2.0
 * @uses $wp_rewrite
 *
 * @param $string String a URL with or without a trailing slash.
 * @param $type_of_url String the type of URL being considered (e.g. single, category, etc) for use in the filter.
 * @return string
 */
function user_trailingslashit($string, $type_of_url = '') {
    global $wp_rewrite;
    if ( $wp_rewrite->use_trailing_slashes )
        $string = trailingslashit($string);
    else
        $string = untrailingslashit($string);

    // Note that $type_of_url can be one of following:
    // single, single_trackback, single_feed, single_paged, feed, category, page, year, month, day, paged
    $string = apply_filters('user_trailingslashit', $string, $type_of_url);
    return $string;
}

/**
 * Display permalink anchor for current post.
 *
 * The permalink mode title will use the post title for the 'a' element 'id'
 * attribute. The id mode uses 'post-' with the post ID for the 'id' attribute.
 *
 * @since 0.71
 *
 * @param string $mode Permalink mode can be either 'title', 'id', or default, which is 'id'.
 */
function permalink_anchor($mode = 'id') {
    global $post;
    switch ( strtolower($mode) ) {
        case 'title':
            $title = sanitize_title($post->post_title) . '-' . $post->ID;
            echo '<a id="'.$title.'"></a>';
            break;
        case 'id':
        default:
            echo '<a id="post-' . $post->ID . '"></a>';
            break;
    }
}

/**
 * Retrieve full permalink for current post or post ID.
 *
 * @since 1.0.0
 *
 * @param int $id Optional. Post ID.
 * @param bool $leavename Optional, defaults to false. Whether to keep post name or page name.
 * @return string
 */
function get_permalink($id = 0, $leavename = false) {
    $rewritecode = array(
        '%year%',
        '%monthnum%',
        '%day%',
        '%hour%',
        '%minute%',
        '%second%',
        $leavename? '' : '%postname%',
        '%post_id%',
        '%category%',
        '%author%',
        $leavename? '' : '%pagename%',
    );

    if ( is_object($id) && isset($id->filter) && 'sample' == $id->filter ) {
        $post = $id;
        $sample = true;
    } else {
        $post = &get_post($id);
        $sample = false;
    }

    if ( empty($post->ID) ) return false;

    if ( $post->post_type == 'page' )
        return get_page_link($post->ID, $leavename, $sample);
    elseif ($post->post_type == 'attachment')
        return get_attachment_link($post->ID);

    $permalink = get_option('permalink_structure');

    if ( '' != $permalink && !in_array($post->post_status, array('draft', 'pending')) ) {
        $unixtime = strtotime($post->post_date);

        $category = '';
        if ( strpos($permalink, '%category%') !== false ) {
            $cats = get_the_category($post->ID);
            if ( $cats ) {
                usort($cats, '_usort_terms_by_ID'); // order by ID
                $category = $cats[0]->slug;
                if ( $parent = $cats[0]->parent )
                    $category = get_category_parents($parent, false, '/', true) . $category;
            }
            // show default category in permalinks, without
            // having to assign it explicitly
            if ( empty($category) ) {
                $default_category = get_category( get_option( 'default_category' ) );
                $category = is_wp_error( $default_category ) ? '' : $default_category->slug;
            }
        }

        $author = '';
        if ( strpos($permalink, '%author%') !== false ) {
            $authordata = get_userdata($post->post_author);
            $author = $authordata->user_nicename;
        }

        $date = explode(" ",date('Y m d H i s', $unixtime));
        $rewritereplace =
        array(
            $date[0],
            $date[1],
            $date[2],
            $date[3],
            $date[4],
            $date[5],
            $post->post_name,
            $post->ID,
            $category,
            $author,
            $post->post_name,
        );
        $permalink = get_option('home') . str_replace($rewritecode, $rewritereplace, $permalink);
        $permalink = user_trailingslashit($permalink, 'single');
        return apply_filters('post_link', $permalink, $post, $leavename);
    } else { // if they're not using the fancy permalink option
        $permalink = trailingslashit(get_option('home')) . '?p=' . $post->ID;
        return apply_filters('post_link', $permalink, $post, $leavename);
    }
}

/**
 * Retrieve permalink from post ID.
 *
 * @since 1.0.0
 *
 * @param int $post_id Optional. Post ID.
 * @param mixed $deprecated Not used.
 * @return string
 */
function post_permalink($post_id = 0, $deprecated = '') {
    return get_permalink($post_id);
}

/**
 * Retrieve the permalink for current page or page ID.
 *
 * Respects page_on_front. Use this one.
 *
 * @since 1.5.0
 *
 * @param int $id Optional. Post ID.
 * @param bool $leavename Optional, defaults to false. Whether to keep page name.
 * @param bool $sample Optional, defaults to false. Is it a sample permalink.
 * @return string
 */
function get_page_link( $id = false, $leavename = false, $sample = false ) {
    global $post;

    $id = (int) $id;
    if ( !$id )
        $id = (int) $post->ID;

    if ( 'page' == get_option('show_on_front') && $id == get_option('page_on_front') )
        $link = get_option('home');
    else
        $link = _get_page_link( $id , $leavename, $sample );

    return apply_filters('page_link', $link, $id);
}

/**
 * Retrieve the page permalink.
 *
 * Ignores page_on_front. Internal use only.
 *
 * @since 2.1.0
 * @access private
 *
 * @param int $id Optional. Post ID.
 * @param bool $leavename Optional. Leave name.
 * @param bool $sample Optional. Sample permalink.
 * @return string
 */
function _get_page_link( $id = false, $leavename = false, $sample = false ) {
    global $post, $wp_rewrite;

    if ( !$id )
        $id = (int) $post->ID;
    else
        $post = &get_post($id);

    $pagestruct = $wp_rewrite->get_page_permastruct();

    if ( '' != $pagestruct && ( ( isset($post->post_status) && 'draft' != $post->post_status && 'pending' != $post->post_status ) || $sample ) ) {
        $link = get_page_uri($id);
        $link = ( $leavename ) ? $pagestruct : str_replace('%pagename%', $link, $pagestruct);
        $link = trailingslashit(get_option('home')) . "$link";
        $link = user_trailingslashit($link, 'page');
    } else {
        $link = trailingslashit(get_option('home')) . "?page_id=$id";
    }

    return apply_filters( '_get_page_link', $link, $id );
}

/**
 * Retrieve permalink for attachment.
 *
 * This can be used in the WordPress Loop or outside of it.
 *
 * @since 2.0.0
 *
 * @param int $id Optional. Post ID.
 * @return string
 */
function get_attachment_link($id = false) {
    global $post, $wp_rewrite;

    $link = false;

    if (! $id) {
        $id = (int) $post->ID;
    }

    $object = get_post($id);
    if ( $wp_rewrite->using_permalinks() && ($object->post_parent > 0) && ($object->post_parent != $id) ) {
        $parent = get_post($object->post_parent);
        if ( 'page' == $parent->post_type )
            $parentlink = _get_page_link( $object->post_parent ); // Ignores page_on_front
        else
            $parentlink = get_permalink( $object->post_parent );
        if ( is_numeric($object->post_name) || false !== strpos(get_option('permalink_structure'), '%category%') )
            $name = 'attachment/' . $object->post_name; // <permalink>/<int>/ is paged so we use the explicit attachment marker
        else
            $name = $object->post_name;
        if (strpos($parentlink, '?') === false)
            $link = user_trailingslashit( trailingslashit($parentlink) . $name );
    }

    if (! $link ) {
        $link = trailingslashit(get_bloginfo('url')) . "?attachment_id=$id";
    }

    return apply_filters('attachment_link', $link, $id);
}

/**
 * Retrieve the permalink for the year archives.
 *
 * @since 1.5.0
 *
 * @param int|bool $year False for current year or year for permalink.
 * @return string
 */
function get_year_link($year) {
    global $wp_rewrite;
    if ( !$year )
        $year = gmdate('Y', time()+(get_option('gmt_offset') * 3600));
    $yearlink = $wp_rewrite->get_year_permastruct();
    if ( !empty($yearlink) ) {
        $yearlink = str_replace('%year%', $year, $yearlink);
        return apply_filters('year_link', get_option('home') . user_trailingslashit($yearlink, 'year'), $year);
    } else {
        return apply_filters('year_link', trailingslashit(get_option('home')) . '?m=' . $year, $year);
    }
}

/**
 * Retrieve the permalink for the month archives with year.
 *
 * @since 1.0.0
 *
 * @param bool|int $year False for current year. Integer of year.
 * @param bool|int $month False for current month. Integer of month.
 * @return string
 */
function get_month_link($year, $month) {
    global $wp_rewrite;
    if ( !$year )
        $year = gmdate('Y', time()+(get_option('gmt_offset') * 3600));
    if ( !$month )
        $month = gmdate('m', time()+(get_option('gmt_offset') * 3600));
    $monthlink = $wp_rewrite->get_month_permastruct();
    if ( !empty($monthlink) ) {
        $monthlink = str_replace('%year%', $year, $monthlink);
        $monthlink = str_replace('%monthnum%', zeroise(intval($month), 2), $monthlink);
        return apply_filters('month_link', get_option('home') . user_trailingslashit($monthlink, 'month'), $year, $month);
    } else {
        return apply_filters('month_link', trailingslashit(get_option('home')) . '?m=' . $year . zeroise($month, 2), $year, $month);
    }
}

/**
 * Retrieve the permalink for the day archives with year and month.
 *
 * @since 1.0.0
 *
 * @param bool|int $year False for current year. Integer of year.
 * @param bool|int $month False for current month. Integer of month.
 * @param bool|int $day False for current day. Integer of day.
 * @return string
 */
function get_day_link($year, $month, $day) {
    global $wp_rewrite;
    if ( !$year )
        $year = gmdate('Y', time()+(get_option('gmt_offset') * 3600));
    if ( !$month )
        $month = gmdate('m', time()+(get_option('gmt_offset') * 3600));
    if ( !$day )
        $day = gmdate('j', time()+(get_option('gmt_offset') * 3600));

    $daylink = $wp_rewrite->get_day_permastruct();
    if ( !empty($daylink) ) {
        $daylink = str_replace('%year%', $year, $daylink);
        $daylink = str_replace('%monthnum%', zeroise(intval($month), 2), $daylink);
        $daylink = str_replace('%day%', zeroise(intval($day), 2), $daylink);
        return apply_filters('day_link', get_option('home') . user_trailingslashit($daylink, 'day'), $year, $month, $day);
    } else {
        return apply_filters('day_link', trailingslashit(get_option('home')) . '?m=' . $year . zeroise($month, 2) . zeroise($day, 2), $year, $month, $day);
    }
}

/**
 * Retrieve the permalink for the feed type.
 *
 * @since 1.5.0
 *
 * @param string $feed Optional, defaults to default feed. Feed type.
 * @return string
 */
function get_feed_link($feed = '') {
    global $wp_rewrite;

    $permalink = $wp_rewrite->get_feed_permastruct();
    if ( '' != $permalink ) {
        if ( false !== strpos($feed, 'comments_') ) {
            $feed = str_replace('comments_', '', $feed);
            $permalink = $wp_rewrite->get_comment_feed_permastruct();
        }

        if ( get_default_feed() == $feed )
            $feed = '';

        $permalink = str_replace('%feed%', $feed, $permalink);
        $permalink = preg_replace('#/+#', '/', "/$permalink");
        $output =  get_option('home') . user_trailingslashit($permalink, 'feed');
    } else {
        if ( empty($feed) )
            $feed = get_default_feed();

        if ( false !== strpos($feed, 'comments_') )
            $feed = str_replace('comments_', 'comments-', $feed);

        $output = trailingslashit(get_option('home')) . "?feed={$feed}";
    }

    return apply_filters('feed_link', $output, $feed);
}

/**
 * Retrieve the permalink for the post comments feed.
 *
 * @since 2.2.0
 *
 * @param int $post_id Optional. Post ID.
 * @param string $feed Optional. Feed type.
 * @return string
 */
function get_post_comments_feed_link($post_id = '', $feed = '') {
    global $id;

    if ( empty($post_id) )
        $post_id = (int) $id;

    if ( empty($feed) )
        $feed = get_default_feed();

    if ( '' != get_option('permalink_structure') ) {
        $url = trailingslashit( get_permalink($post_id) ) . 'feed';
        if ( $feed != get_default_feed() )
            $url .= "/$feed";
        $url = user_trailingslashit($url, 'single_feed');
    } else {
        $type = get_post_field('post_type', $post_id);
        if ( 'page' == $type )
            $url = trailingslashit(get_option('home')) . "?feed=$feed&amp;page_id=$post_id";
        else
            $url = trailingslashit(get_option('home')) . "?feed=$feed&amp;p=$post_id";
    }

    return apply_filters('post_comments_feed_link', $url);
}

/**
 * Display the comment feed link for a post.
 *
 * Prints out the comment feed link for a post. Link text is placed in the
 * anchor. If no link text is specified, default text is used. If no post ID is
 * specified, the current post is used.
 *
 * @package WordPress
 * @subpackage Feed
 * @since 2.5.0
 *
 * @param string $link_text Descriptive text.
 * @param int $post_id Optional post ID.  Default to current post.
 * @param string $feed Optional. Feed format.
 * @return string Link to the comment feed for the current post.
*/
function post_comments_feed_link( $link_text = '', $post_id = '', $feed = '' ) {
    $url = get_post_comments_feed_link($post_id, $feed);
    if ( empty($link_text) )
        $link_text = __('Comments Feed');

    echo apply_filters( 'post_comments_feed_link_html', "<a href='$url'>$link_text</a>", $post_id, $feed );
}

/**
 * Retrieve the feed link for a given author.
 *
 * Returns a link to the feed for all posts by a given author. A specific feed
 * can be requested or left blank to get the default feed.
 *
 * @package WordPress
 * @subpackage Feed
 * @since 2.5.0
 *
 * @param int $author_id ID of an author.
 * @param string $feed Optional. Feed type.
 * @return string Link to the feed for the author specified by $author_id.
*/
function get_author_feed_link( $author_id, $feed = '' ) {
    $author_id = (int) $author_id;
    $permalink_structure = get_option('permalink_structure');

    if ( empty($feed) )
        $feed = get_default_feed();

    if ( '' == $permalink_structure ) {
        $link = trailingslashit(get_option('home')) . "?feed=$feed&amp;author=" . $author_id;
    } else {
        $link = get_author_posts_url($author_id);
        if ( $feed == get_default_feed() )
            $feed_link = 'feed';
        else
            $feed_link = "feed/$feed";

        $link = trailingslashit($link) . user_trailingslashit($feed_link, 'feed');
    }

    $link = apply_filters('author_feed_link', $link, $feed);

    return $link;
}

/**
 * Retrieve the feed link for a category.
 *
 * Returns a link to the feed for all post in a given category. A specific feed
 * can be requested or left blank to get the default feed.
 *
 * @package WordPress
 * @subpackage Feed
 * @since 2.5.0
 *
 * @param int $cat_id ID of a category.
 * @param string $feed Optional. Feed type.
 * @return string Link to the feed for the category specified by $cat_id.
*/
function get_category_feed_link($cat_id, $feed = '') {
    $cat_id = (int) $cat_id;

    $category = get_category($cat_id);

    if ( empty($category) || is_wp_error($category) )
        return false;

    if ( empty($feed) )
        $feed = get_default_feed();

    $permalink_structure = get_option('permalink_structure');

    if ( '' == $permalink_structure ) {
        $link = trailingslashit(get_option('home')) . "?feed=$feed&amp;cat=" . $cat_id;
    } else {
        $link = get_category_link($cat_id);
        if( $feed == get_default_feed() )
            $feed_link = 'feed';
        else
            $feed_link = "feed/$feed";

        $link = trailingslashit($link) . user_trailingslashit($feed_link, 'feed');
    }

    $link = apply_filters('category_feed_link', $link, $feed);

    return $link;
}

/**
 * Retrieve permalink for feed of tag.
 *
 * @since 2.3.0
 *
 * @param int $tag_id Tag ID.
 * @param string $feed Optional. Feed type.
 * @return string
 */
function get_tag_feed_link($tag_id, $feed = '') {
    $tag_id = (int) $tag_id;

    $tag = get_tag($tag_id);

    if ( empty($tag) || is_wp_error($tag) )
        return false;

    $permalink_structure = get_option('permalink_structure');

    if ( empty($feed) )
        $feed = get_default_feed();

    if ( '' == $permalink_structure ) {
        $link = trailingslashit(get_option('home')) . "?feed=$feed&amp;tag=" . $tag->slug;
    } else {
        $link = get_tag_link($tag->term_id);
        if ( $feed == get_default_feed() )
            $feed_link = 'feed';
        else
            $feed_link = "feed/$feed";
        $link = trailingslashit($link) . user_trailingslashit($feed_link, 'feed');
    }

    $link = apply_filters('tag_feed_link', $link, $feed);

    return $link;
}

/**
 * Retrieve edit tag link.
 *
 * @since 2.7.0
 *
 * @param int $tag_id Tag ID
 * @return string
 */
function get_edit_tag_link( $tag_id = 0, $taxonomy = 'post_tag' ) {
    $tag = get_term($tag_id, $taxonomy);

    if ( !current_user_can('manage_categories') )
        return;

    $location = admin_url('edit-tags.php?action=edit&amp;taxonomy=' . $taxonomy . '&amp;tag_ID=' . $tag->term_id);
    return apply_filters( 'get_edit_tag_link', $location );
}

/**
 * Display or retrieve edit tag link with formatting.
 *
 * @since 2.7.0
 *
 * @param string $link Optional. Anchor text.
 * @param string $before Optional. Display before edit link.
 * @param string $after Optional. Display after edit link.
 * @param int|object $tag Tag object or ID
 * @return string|null HTML content, if $echo is set to false.
 */
function edit_tag_link( $link = '', $before = '', $after = '', $tag = null ) {
    $tag = get_term($tag, 'post_tag');

    if ( !current_user_can('manage_categories') )
        return;

    if ( empty($link) )
        $link = __('Edit This');

    $link = '<a href="' . get_edit_tag_link( $tag->term_id ) . '" title="' . __( 'Edit tag' ) . '">' . $link . '</a>';
    echo $before . apply_filters( 'edit_tag_link', $link, $tag->term_id ) . $after;
}

/**
 * Retrieve the permalink for the feed of the search results.
 *
 * @since 2.5.0
 *
 * @param string $search_query Optional. Search query.
 * @param string $feed Optional. Feed type.
 * @return string
 */
function get_search_feed_link($search_query = '', $feed = '') {
    if ( empty($search_query) )
        $search = esc_attr( urlencode(get_search_query()) );
    else
        $search = esc_attr( urlencode(stripslashes($search_query)) );

    if ( empty($feed) )
        $feed = get_default_feed();

    $link = trailingslashit(get_option('home')) . "?s=$search&amp;feed=$feed";

    $link = apply_filters('search_feed_link', $link);

    return $link;
}

/**
 * Retrieve the permalink for the comments feed of the search results.
 *
 * @since 2.5.0
 *
 * @param string $search_query Optional. Search query.
 * @param string $feed Optional. Feed type.
 * @return string
 */
function get_search_comments_feed_link($search_query = '', $feed = '') {
    if ( empty($search_query) )
        $search = esc_attr( urlencode(get_search_query()) );
    else
        $search = esc_attr( urlencode(stripslashes($search_query)) );

    if ( empty($feed) )
        $feed = get_default_feed();

    $link = trailingslashit(get_option('home')) . "?s=$search&amp;feed=comments-$feed";

    $link = apply_filters('search_feed_link', $link);

    return $link;
}

/**
 * Retrieve edit posts link for post.
 *
 * Can be used within the WordPress loop or outside of it. Can be used with
 * pages, posts, attachments, and revisions.
 *
 * @since 2.3.0
 *
 * @param int $id Optional. Post ID.
 * @param string $context Optional, default to display. How to write the '&', defaults to '&amp;'.
 * @return string
 */
function get_edit_post_link( $id = 0, $context = 'display' ) {
    if ( !$post = &get_post( $id ) )
        return;

    if ( 'display' == $context )
        $action = 'action=edit&amp;';
    else
        $action = 'action=edit&';

    switch ( $post->post_type ) :
    case 'page' :
        if ( !current_user_can( 'edit_page', $post->ID ) )
            return;
        $file = 'page';
        $var  = 'post';
        break;
    case 'attachment' :
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return;
        $file = 'media';
        $var  = 'attachment_id';
        break;
    case 'revision' :
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return;
        $file = 'revision';
        $var  = 'revision';
        $action = '';
        break;
    default :
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return apply_filters( 'get_edit_post_link', '', $post->ID, $context );;
        $file = 'post';
        $var  = 'post';
        break;
    endswitch;

    return apply_filters( 'get_edit_post_link', admin_url("$file.php?{$action}$var=$post->ID"), $post->ID, $context );
}

/**
 * Display edit post link for post.
 *
 * @since 1.0.0
 *
 * @param string $link Optional. Anchor text.
 * @param string $before Optional. Display before edit link.
 * @param string $after Optional. Display after edit link.
 * @param int $id Optional. Post ID.
 */
function edit_post_link( $link = null, $before = '', $after = '', $id = 0 ) {
    if ( !$post = &get_post( $id ) )
        return;

    if ( !$url = get_edit_post_link( $post->ID ) )
        return;

    if ( null === $link )
        $link = __('Edit This');

    $link = '<a class="post-edit-link" href="' . $url . '" title="' . esc_attr( __( 'Edit post' ) ) . '">' . $link . '</a>';
    echo $before . apply_filters( 'edit_post_link', $link, $post->ID ) . $after;
}

/**
 * Retrieve delete posts link for post.
 *
 * Can be used within the WordPress loop or outside of it. Can be used with
 * pages, posts, attachments, and revisions.
 *
 * @since 2.9.0
 *
 * @param int $id Optional. Post ID.
 * @param string $context Optional, default to display. How to write the '&', defaults to '&amp;'.
 * @return string
 */
function get_delete_post_link($id = 0, $context = 'display') {
    if ( !$post = &get_post( $id ) )
        return;

    if ( 'display' == $context )
        $action = 'action=trash&amp;';
    else
        $action = 'action=trash&';

    switch ( $post->post_type ) :
    case 'page' :
        if ( !current_user_can( 'delete_page', $post->ID ) )
            return;
        $file = 'page';
        $var  = 'post';
        break;
    case 'attachment' :
        if ( !current_user_can( 'delete_post', $post->ID ) )
            return;
        $file = 'media';
        $var  = 'attachment_id';
        break;
    case 'revision' :
        if ( !current_user_can( 'delete_post', $post->ID ) )
            return;
        $file = 'revision';
        $var  = 'revision';
        $action = '';
        break;
    default :
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return apply_filters( 'get_delete_post_link', '', $post->ID, $context );;
        $file = 'post';
        $var  = 'post';
        break;
    endswitch;

    return apply_filters( 'get_delete_post_link', wp_nonce_url( admin_url("$file.php?{$action}$var=$post->ID"), "trash-{$file}_" . $post->ID ), $context );
}

/**
 * Retrieve edit comment link.
 *
 * @since 2.3.0
 *
 * @param int $comment_id Optional. Comment ID.
 * @return string
 */
function get_edit_comment_link( $comment_id = 0 ) {
    $comment = &get_comment( $comment_id );
    $post = &get_post( $comment->comment_post_ID );

    if ( $post->post_type == 'page' ) {
        if ( !current_user_can( 'edit_page', $post->ID ) )
            return;
    } else {
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return;
    }

    $location = admin_url('comment.php?action=editcomment&amp;c=') . $comment->comment_ID;
    return apply_filters( 'get_edit_comment_link', $location );
}

/**
 * Display or retrieve edit comment link with formatting.
 *
 * @since 1.0.0
 *
 * @param string $link Optional. Anchor text.
 * @param string $before Optional. Display before edit link.
 * @param string $after Optional. Display after edit link.
 * @return string|null HTML content, if $echo is set to false.
 */
function edit_comment_link( $link = null, $before = '', $after = '' ) {
    global $comment, $post;

    if ( $post->post_type == 'page' ) {
        if ( !current_user_can( 'edit_page', $post->ID ) )
            return;
    } else {
        if ( !current_user_can( 'edit_post', $post->ID ) )
            return;
    }

    if ( null === $link )
        $link = __('Edit This');

    $link = '<a class="comment-edit-link" href="' . get_edit_comment_link( $comment->comment_ID ) . '" title="' . __( 'Edit comment' ) . '">' . $link . '</a>';
    echo $before . apply_filters( 'edit_comment_link', $link, $comment->comment_ID ) . $after;
}

/**
 * Display edit bookmark (literally a URL external to blog) link.
 *
 * @since 2.7.0
 *
 * @param int $link Optional. Bookmark ID.
 * @return string
 */
function get_edit_bookmark_link( $link = 0 ) {
    $link = get_bookmark( $link );

    if ( !current_user_can('manage_links') )
        return;

    $location = admin_url('link.php?action=edit&amp;link_id=') . $link->link_id;
    return apply_filters( 'get_edit_bookmark_link', $location, $link->link_id );
}

/**
 * Display edit bookmark (literally a URL external to blog) link anchor content.
 *
 * @since 2.7.0
 *
 * @param string $link Optional. Anchor text.
 * @param string $before Optional. Display before edit link.
 * @param string $after Optional. Display after edit link.
 * @param int $bookmark Optional. Bookmark ID.
 */
function edit_bookmark_link( $link = '', $before = '', $after = '', $bookmark = null ) {
    $bookmark = get_bookmark($bookmark);

    if ( !current_user_can('manage_links') )
        return;

    if ( empty($link) )
        $link = __('Edit This');

    $link = '<a href="' . get_edit_bookmark_link( $link ) . '" title="' . __( 'Edit link' ) . '">' . $link . '</a>';
    echo $before . apply_filters( 'edit_bookmark_link', $link, $bookmark->link_id ) . $after;
}

// Navigation links

/**
 * Retrieve previous post link that is adjacent to current post.
 *
 * @since 1.5.0
 *
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @return string
 */
function get_previous_post($in_same_cat = false, $excluded_categories = '') {
    return get_adjacent_post($in_same_cat, $excluded_categories);
}

/**
 * Retrieve next post link that is adjacent to current post.
 *
 * @since 1.5.0
 *
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @return string
 */
function get_next_post($in_same_cat = false, $excluded_categories = '') {
    return get_adjacent_post($in_same_cat, $excluded_categories, false);
}

/**
 * Retrieve adjacent post link.
 *
 * Can either be next or previous post link.
 *
 * @since 2.5.0
 *
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @param bool $previous Optional. Whether to retrieve previous post.
 * @return string
 */
function get_adjacent_post($in_same_cat = false, $excluded_categories = '', $previous = true) {
    global $post, $wpdb;

    if ( empty($post) || !is_single() || is_attachment() )
        return null;

    $current_post_date = $post->post_date;

    $join = '';
    $posts_in_ex_cats_sql = '';
    if ( $in_same_cat || !empty($excluded_categories) ) {
        $join = " INNER JOIN $wpdb->term_relationships AS tr ON p.ID = tr.object_id INNER JOIN $wpdb->term_taxonomy tt ON tr.term_taxonomy_id = tt.term_taxonomy_id";

        if ( $in_same_cat ) {
            $cat_array = wp_get_object_terms($post->ID, 'category', 'fields=ids');
            $join .= " AND tt.taxonomy = 'category' AND tt.term_id IN (" . implode(',', $cat_array) . ")";
        }

        $posts_in_ex_cats_sql = "AND tt.taxonomy = 'category'";
        if ( !empty($excluded_categories) ) {
            $excluded_categories = array_map('intval', explode(' and ', $excluded_categories));
            if ( !empty($cat_array) ) {
                $excluded_categories = array_diff($excluded_categories, $cat_array);
                $posts_in_ex_cats_sql = '';
            }

            if ( !empty($excluded_categories) ) {
                $posts_in_ex_cats_sql = " AND tt.taxonomy = 'category' AND tt.term_id NOT IN (" . implode($excluded_categories, ',') . ')';
            }
        }
    }

    $adjacent = $previous ? 'previous' : 'next';
    $op = $previous ? '<' : '>';
    $order = $previous ? 'DESC' : 'ASC';

    $join  = apply_filters( "get_{$adjacent}_post_join", $join, $in_same_cat, $excluded_categories );
    $where = apply_filters( "get_{$adjacent}_post_where", $wpdb->prepare("WHERE p.post_date $op %s AND p.post_type = %s AND p.post_status = 'publish' $posts_in_ex_cats_sql", $current_post_date, $post->post_type), $in_same_cat, $excluded_categories );
    $sort  = apply_filters( "get_{$adjacent}_post_sort", "ORDER BY p.post_date $order LIMIT 1" );

    $query = "SELECT p.* FROM $wpdb->posts AS p $join $where $sort";
    $query_key = 'adjacent_post_' . md5($query);
    $result = wp_cache_get($query_key, 'counts');
    if ( false !== $result )
        return $result;

    $result = $wpdb->get_row("SELECT p.* FROM $wpdb->posts AS p $join $where $sort");
    if ( null === $result )
        $result = '';

    wp_cache_set($query_key, $result, 'counts');
    return $result;
}

/**
 * Get adjacent post relational link.
 *
 * Can either be next or previous post relational link.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @param bool $previous Optional, default is true. Whether display link to previous post.
 * @return string
 */
function get_adjacent_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '', $previous = true) {
    if ( $previous && is_attachment() )
        $post = & get_post($GLOBALS['post']->post_parent);
    else
        $post = get_adjacent_post($in_same_cat,$excluded_categories,$previous);

    if ( empty($post) )
        return;

    if ( empty($post->post_title) )
        $post->post_title = $previous ? __('Previous Post') : __('Next Post');

    $date = mysql2date(get_option('date_format'), $post->post_date);

    $title = str_replace('%title', $post->post_title, $title);
    $title = str_replace('%date', $date, $title);
    $title = apply_filters('the_title', $title, $post);

    $link = $previous ? "<link rel='prev' title='" : "<link rel='next' title='";
    $link .= esc_attr( $title );
    $link .= "' href='" . get_permalink($post) . "' />\n";

    $adjacent = $previous ? 'previous' : 'next';
    return apply_filters( "{$adjacent}_post_rel_link", $link );
}

/**
 * Display relational links for the posts adjacent to the current post.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function adjacent_posts_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '') {
    echo get_adjacent_post_rel_link($title, $in_same_cat, $excluded_categories = '', true);
    echo get_adjacent_post_rel_link($title, $in_same_cat, $excluded_categories = '', false);
}

/**
 * Display relational link for the next post adjacent to the current post.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function next_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '') {
    echo get_adjacent_post_rel_link($title, $in_same_cat, $excluded_categories = '', false);
}

/**
 * Display relational link for the previous post adjacent to the current post.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function prev_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '') {
    echo get_adjacent_post_rel_link($title, $in_same_cat, $excluded_categories = '', true);
}

/**
 * Retrieve boundary post.
 *
 * Boundary being either the first or last post by publish date within the contraitns specified
 * by in same category or excluded categories.
 *
 * @since 2.8.0
 *
 * @param bool $in_same_cat Optional. Whether returned post should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @param bool $previous Optional. Whether to retrieve first post.
 * @return object
 */
function get_boundary_post($in_same_cat = false, $excluded_categories = '', $start = true) {
    global $post, $wpdb;

    if ( empty($post) || !is_single() || is_attachment() )
        return null;

    $cat_array = array();
    $excluded_categories = array();
    if ( !empty($in_same_cat) || !empty($excluded_categories) ) {
        if ( !empty($in_same_cat) ) {
            $cat_array = wp_get_object_terms($post->ID, 'category', 'fields=ids');
        }

        if ( !empty($excluded_categories) ) {
            $excluded_categories = array_map('intval', explode(',', $excluded_categories));

            if ( !empty($cat_array) )
                $excluded_categories = array_diff($excluded_categories, $cat_array);

            $inverse_cats = array();
            foreach ( $excluded_categories as $excluded_category)
                $inverse_cats[] = $excluded_category * -1;
            $excluded_categories = $inverse_cats;
        }
    }

    $categories = implode(',', array_merge($cat_array, $excluded_categories) );

    $order = $start ? 'ASC' : 'DESC';

    return get_posts( array('numberposts' => 1, 'order' => $order, 'orderby' => 'ID', 'category' => $categories) );
}

/**
 * Get boundary post relational link.
 *
 * Can either be start or end post relational link.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @param bool $start Optional, default is true. Whether display link to first post.
 * @return string
 */
function get_boundary_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '', $start = true) {
    $posts = get_boundary_post($in_same_cat,$excluded_categories,$start);
    // Even though we limited get_posts to return only 1 item it still returns an array of objects.
    $post = $posts[0];

    if ( empty($post) )
             return;

        if ( empty($post->post_title) )
                $post->post_title = $start ? __('First Post') : __('Last Post');

    $date = mysql2date(get_option('date_format'), $post->post_date);

    $title = str_replace('%title', $post->post_title, $title);
    $title = str_replace('%date', $date, $title);
    $title = apply_filters('the_title', $title, $post);

    $link = $start ? "<link rel='start' title='" : "<link rel='end' title='";
    $link .= esc_attr($title);
    $link .= "' href='" . get_permalink($post) . "' />\n";

    $boundary = $start ? 'start' : 'end';
    return apply_filters( "{$boundary}_post_rel_link", $link );
}

/**
 * Display relational link for the first post.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function start_post_rel_link($title = '%title', $in_same_cat = false, $excluded_categories = '') {
    echo get_boundary_post_rel_link($title, $in_same_cat, $excluded_categories, true);
}

/**
 * Get site index relational link.
 *
 * @since 2.8.0
 *
 * @return string
 */
function get_index_rel_link() {
    $link = "<link rel='index' title='" . esc_attr(get_bloginfo('name')) . "' href='" . get_bloginfo('siteurl') . "' />\n";
    return apply_filters( "index_rel_link", $link );
}

/**
 * Display relational link for the site index.
 *
 * @since 2.8.0
 */
function index_rel_link() {
    echo get_index_rel_link();
}

/**
 * Get parent post relational link.
 *
 * @since 2.8.0
 *
 * @param string $title Optional. Link title format.
 * @return string
 */
function get_parent_post_rel_link($title = '%title') {
    if ( ! empty( $GLOBALS['post'] ) && ! empty( $GLOBALS['post']->post_parent ) )
        $post = & get_post($GLOBALS['post']->post_parent);

    if ( empty($post) )
        return;

    $date = mysql2date(get_option('date_format'), $post->post_date);

    $title = str_replace('%title', $post->post_title, $title);
    $title = str_replace('%date', $date, $title);
    $title = apply_filters('the_title', $title, $post);

    $link = "<link rel='up' title='";
    $link .= esc_attr( $title );
    $link .= "' href='" . get_permalink($post) . "' />\n";

    return apply_filters( "parent_post_rel_link", $link );
}

/**
 * Display relational link for parent item
 *
 * @since 2.8.0
 */
function parent_post_rel_link($title = '%title') {
    echo get_parent_post_rel_link($title);
}

/**
 * Display previous post link that is adjacent to the current post.
 *
 * @since 1.5.0
 *
 * @param string $format Optional. Link anchor format.
 * @param string $link Optional. Link permalink format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function previous_post_link($format='&laquo; %link', $link='%title', $in_same_cat = false, $excluded_categories = '') {
    adjacent_post_link($format, $link, $in_same_cat, $excluded_categories, true);
}

/**
 * Display next post link that is adjacent to the current post.
 *
 * @since 1.5.0
 *
 * @param string $format Optional. Link anchor format.
 * @param string $link Optional. Link permalink format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 */
function next_post_link($format='%link &raquo;', $link='%title', $in_same_cat = false, $excluded_categories = '') {
    adjacent_post_link($format, $link, $in_same_cat, $excluded_categories, false);
}

/**
 * Display adjacent post link.
 *
 * Can be either next post link or previous.
 *
 * @since 2.5.0
 *
 * @param string $format Link anchor format.
 * @param string $link Link permalink format.
 * @param bool $in_same_cat Optional. Whether link should be in same category.
 * @param string $excluded_categories Optional. Excluded categories IDs.
 * @param bool $previous Optional, default is true. Whether display link to previous post.
 */
function adjacent_post_link($format, $link, $in_same_cat = false, $excluded_categories = '', $previous = true) {
    if ( $previous && is_attachment() )
        $post = & get_post($GLOBALS['post']->post_parent);
    else
        $post = get_adjacent_post($in_same_cat, $excluded_categories, $previous);

    if ( !$post )
        return;

    $title = $post->post_title;

    if ( empty($post->post_title) )
        $title = $previous ? __('Previous Post') : __('Next Post');

    $title = apply_filters('the_title', $title, $post);
    $date = mysql2date(get_option('date_format'), $post->post_date);
    $rel = $previous ? 'prev' : 'next';

    $string = '<a href="'.get_permalink($post).'" rel="'.$rel.'">';
    $link = str_replace('%title', $title, $link);
    $link = str_replace('%date', $date, $link);
    $link = $string . $link . '</a>';

    $format = str_replace('%link', $link, $format);

    $adjacent = $previous ? 'previous' : 'next';
    echo apply_filters( "{$adjacent}_post_link", $format, $link );
}

/**
 * Retrieve get links for page numbers.
 *
 * @since 1.5.0
 *
 * @param int $pagenum Optional. Page ID.
 * @return string
 */
function get_pagenum_link($pagenum = 1) {
    global $wp_rewrite;

    $pagenum = (int) $pagenum;

    $request = remove_query_arg( 'paged' );

    $home_root = parse_url(get_option('home'));
    $home_root = ( isset($home_root['path']) ) ? $home_root['path'] : '';
    $home_root = preg_quote( trailingslashit( $home_root ), '|' );

    $request = preg_replace('|^'. $home_root . '|', '', $request);
    $request = preg_replace('|^/+|', '', $request);

    if ( !$wp_rewrite->using_permalinks() || is_admin() ) {
        $base = trailingslashit( get_bloginfo( 'home' ) );

        if ( $pagenum > 1 ) {
            $result = add_query_arg( 'paged', $pagenum, $base . $request );
        } else {
            $result = $base . $request;
        }
    } else {
        $qs_regex = '|\?.*?$|';
        preg_match( $qs_regex, $request, $qs_match );

        if ( !empty( $qs_match[0] ) ) {
            $query_string = $qs_match[0];
            $request = preg_replace( $qs_regex, '', $request );
        } else {
            $query_string = '';
        }

        $request = preg_replace( '|page/\d+/?$|', '', $request);
        $request = preg_replace( '|^index\.php|', '', $request);
        $request = ltrim($request, '/');

        $base = trailingslashit( get_bloginfo( 'url' ) );

        if ( $wp_rewrite->using_index_permalinks() && ( $pagenum > 1 || '' != $request ) )
            $base .= 'index.php/';

        if ( $pagenum > 1 ) {
            $request = ( ( !empty( $request ) ) ? trailingslashit( $request ) : $request ) . user_trailingslashit( 'page/' . $pagenum, 'paged' );
        }

        $result = $base . $request . $query_string;
    }

    $result = apply_filters('get_pagenum_link', $result);

    return $result;
}

/**
 * Retrieve next posts pages link.
 *
 * Backported from 2.1.3 to 2.0.10.
 *
 * @since 2.0.10
 *
 * @param int $max_page Optional. Max pages.
 * @return string
 */
function get_next_posts_page_link($max_page = 0) {
    global $paged;

    if ( !is_single() ) {
        if ( !$paged )
            $paged = 1;
        $nextpage = intval($paged) + 1;
        if ( !$max_page || $max_page >= $nextpage )
            return get_pagenum_link($nextpage);
    }
}

/**
 * Display or return the next posts pages link.
 *
 * @since 0.71
 *
 * @param int $max_page Optional. Max pages.
 * @param boolean $echo Optional. Echo or return;
 */
function next_posts( $max_page = 0, $echo = true ) {
    $output = esc_url( get_next_posts_page_link( $max_page ) );

    if ( $echo )
        echo $output;
    else
        return $output;
}

/**
 * Return the next posts pages link.
 *
 * @since 2.7.0
 *
 * @param string $label Content for link text.
 * @param int $max_page Optional. Max pages.
 * @return string|null
 */
function get_next_posts_link( $label = 'Next Page &raquo;', $max_page = 0 ) {
    global $paged, $wp_query;

    if ( !$max_page ) {
        $max_page = $wp_query->max_num_pages;
    }

    if ( !$paged )
        $paged = 1;

    $nextpage = intval($paged) + 1;

    if ( !is_single() && ( empty($paged) || $nextpage <= $max_page) ) {
        $attr = apply_filters( 'next_posts_link_attributes', '' );
        return '<a href="' . next_posts( $max_page, false ) . "\" $attr>". preg_replace('/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $label) .'</a>';
    }
}

/**
 * Display the next posts pages link.
 *
 * @since 0.71
 * @uses get_next_posts_link()
 *
 * @param string $label Content for link text.
 * @param int $max_page Optional. Max pages.
 */
function next_posts_link( $label = 'Next Page &raquo;', $max_page = 0 ) {
    echo get_next_posts_link( $label, $max_page );
}

/**
 * Retrieve previous post pages link.
 *
 * Will only return string, if not on a single page or post.
 *
 * Backported to 2.0.10 from 2.1.3.
 *
 * @since 2.0.10
 *
 * @return string|null
 */
function get_previous_posts_page_link() {
    global $paged;

    if ( !is_single() ) {
        $nextpage = intval($paged) - 1;
        if ( $nextpage < 1 )
            $nextpage = 1;
        return get_pagenum_link($nextpage);
    }
}

/**
 * Display or return the previous posts pages link.
 *
 * @since 0.71
 *
 * @param boolean $echo Optional. Echo or return;
 */
function previous_posts( $echo = true ) {
    $output = esc_url( get_previous_posts_page_link() );

    if ( $echo )
        echo $output;
    else
        return $output;
}

/**
 * Return the previous posts pages link.
 *
 * @since 2.7.0
 *
 * @param string $label Optional. Previous page link text.
 * @return string|null
 */
function get_previous_posts_link( $label = '&laquo; Previous Page' ) {
    global $paged;

    if ( !is_single() && $paged > 1 ) {
        $attr = apply_filters( 'previous_posts_link_attributes', '' );
        return '<a href="' . previous_posts( false ) . "\" $attr>". preg_replace( '/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $label ) .'</a>';
    }
}

/**
 * Display the previous posts page link.
 *
 * @since 0.71
 * @uses get_previous_posts_link()
 *
 * @param string $label Optional. Previous page link text.
 */
function previous_posts_link( $label = '&laquo; Previous Page' ) {
    echo get_previous_posts_link( $label );
}

/**
 * Return post pages link navigation for previous and next pages.
 *
 * @since 2.8
 *
 * @param string|array $args Optional args.
 * @return string The posts link navigation.
 */
function get_posts_nav_link( $args = array() ) {
    global $wp_query;

    $return = '';

    if ( !is_singular() ) {
        $defaults = array(
            'sep' => ' &#8212; ',
            'prelabel' => __('&laquo; Previous Page'),
            'nxtlabel' => __('Next Page &raquo;'),
        );
        $args = wp_parse_args( $args, $defaults );

        $max_num_pages = $wp_query->max_num_pages;
        $paged = get_query_var('paged');

        //only have sep if there's both prev and next results
        if ($paged < 2 || $paged >= $max_num_pages) {
            $args['sep'] = '';
        }

        if ( $max_num_pages > 1 ) {
            $return = get_previous_posts_link($args['prelabel']);
            $return .= preg_replace('/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $args['sep']);
            $return .= get_next_posts_link($args['nxtlabel']);
        }
    }
    return $return;

}

/**
 * Display post pages link navigation for previous and next pages.
 *
 * @since 0.71
 *
 * @param string $sep Optional. Separator for posts navigation links.
 * @param string $prelabel Optional. Label for previous pages.
 * @param string $nxtlabel Optional Label for next pages.
 */
function posts_nav_link( $sep = '', $prelabel = '', $nxtlabel = '' ) {
    $args = array_filter( compact('sep', 'prelabel', 'nxtlabel') );
    echo get_posts_nav_link($args);
}

/**
 * Retrieve page numbers links.
 *
 * @since 2.7.0
 *
 * @param int $pagenum Optional. Page number.
 * @return string
 */
function get_comments_pagenum_link( $pagenum = 1, $max_page = 0 ) {
    global $post, $wp_rewrite;

    $pagenum = (int) $pagenum;

    $result = get_permalink( $post->ID );

    if ( 'newest' == get_option('default_comments_page') ) {
        if ( $pagenum != $max_page ) {
            if ( $wp_rewrite->using_permalinks() )
                $result = user_trailingslashit( trailingslashit($result) . 'comment-page-' . $pagenum, 'commentpaged');
            else
                $result = add_query_arg( 'cpage', $pagenum, $result );
        }
    } elseif ( $pagenum > 1 ) {
        if ( $wp_rewrite->using_permalinks() )
            $result = user_trailingslashit( trailingslashit($result) . 'comment-page-' . $pagenum, 'commentpaged');
        else
            $result = add_query_arg( 'cpage', $pagenum, $result );
    }

    $result .= '#comments';

    $result = apply_filters('get_comments_pagenum_link', $result);

    return $result;
}

/**
 * Return the link to next comments pages.
 *
 * @since 2.7.1
 *
 * @param string $label Optional. Label for link text.
 * @param int $max_page Optional. Max page.
 * @return string|null
 */
function get_next_comments_link( $label = '', $max_page = 0 ) {
    global $wp_query;

    if ( !is_singular() || !get_option('page_comments') )
        return;

    $page = get_query_var('cpage');

    $nextpage = intval($page) + 1;

    if ( empty($max_page) )
        $max_page = $wp_query->max_num_comment_pages;

    if ( empty($max_page) )
        $max_page = get_comment_pages_count();

    if ( $nextpage > $max_page )
        return;

    if ( empty($label) )
        $label = __('Newer Comments &raquo;');

    return '<a href="' . esc_url( get_comments_pagenum_link( $nextpage, $max_page ) ) . '" ' . apply_filters( 'next_comments_link_attributes', '' ) . '>'. preg_replace('/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $label) .'</a>';
}

/**
 * Display the link to next comments pages.
 *
 * @since 2.7.0
 *
 * @param string $label Optional. Label for link text.
 * @param int $max_page Optional. Max page.
 */
function next_comments_link( $label = '', $max_page = 0 ) {
    echo get_next_comments_link( $label, $max_page );
}

/**
 * Return the previous comments page link.
 *
 * @since 2.7.1
 *
 * @param string $label Optional. Label for comments link text.
 * @return string|null
 */
function get_previous_comments_link( $label = '' ) {
    if ( !is_singular() || !get_option('page_comments') )
        return;

    $page = get_query_var('cpage');

    if ( intval($page) <= 1 )
        return;

    $prevpage = intval($page) - 1;

    if ( empty($label) )
        $label = __('&laquo; Older Comments');

    return '<a href="' . esc_url( get_comments_pagenum_link( $prevpage ) ) . '" ' . apply_filters( 'previous_comments_link_attributes', '' ) . '>' . preg_replace('/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $label) .'</a>';
}

/**
 * Display the previous comments page link.
 *
 * @since 2.7.0
 *
 * @param string $label Optional. Label for comments link text.
 */
function previous_comments_link( $label = '' ) {
    echo get_previous_comments_link( $label );
}

/**
 * Create pagination links for the comments on the current post.
 *
 * @see paginate_links()
 * @since 2.7.0
 *
 * @param string|array $args Optional args. See paginate_links.
 * @return string Markup for pagination links.
*/
function paginate_comments_links($args = array()) {
    global $wp_query, $wp_rewrite;

    if ( !is_singular() || !get_option('page_comments') )
        return;

    $page = get_query_var('cpage');
    if ( !$page )
        $page = 1;
    $max_page = get_comment_pages_count();
    $defaults = array(
        'base' => add_query_arg( 'cpage', '%#%' ),
        'format' => '',
        'total' => $max_page,
        'current' => $page,
        'echo' => true,
        'add_fragment' => '#comments'
    );
    if ( $wp_rewrite->using_permalinks() )
        $defaults['base'] = user_trailingslashit(trailingslashit(get_permalink()) . 'comment-page-%#%', 'commentpaged');

    $args = wp_parse_args( $args, $defaults );
    $page_links = paginate_links( $args );

    if ( $args['echo'] )
        echo $page_links;
    else
        return $page_links;
}

/**
 * Retrieve shortcut link.
 *
 * Use this in 'a' element 'href' attribute.
 *
 * @since 2.6.0
 *
 * @return string
 */
function get_shortcut_link() {
    $link = "javascript:
            var d=document,
            w=window,
            e=w.getSelection,
            k=d.getSelection,
            x=d.selection,
            s=(e?e():(k)?k():(x?x.createRange().text:0)),
            f='" . admin_url('press-this.php') . "',
            l=d.location,
            e=encodeURIComponent,
            u=f+'?u='+e(l.href)+'&t='+e(d.title)+'&s='+e(s)+'&v=4';
            a=function(){if(!w.open(u,'t','toolbar=0,resizable=1,scrollbars=1,status=1,width=720,height=570'))l.href=u;};
            if (/Firefox/.test(navigator.userAgent)) setTimeout(a, 0); else a();
            void(0)";

    $link = str_replace(array("\r", "\n", "\t"),  '', $link);

    return apply_filters('shortcut_link', $link);
}

/**
 * Retrieve the site url.
 *
 * Returns the 'site_url' option with the appropriate protocol,  'https' if
 * is_ssl() and 'http' otherwise. If $scheme is 'http' or 'https', is_ssl() is
 * overridden.
 *
 * @package WordPress
 * @since 2.6.0
 *
 * @param string $path Optional. Path relative to the site url.
 * @param string $scheme Optional. Scheme to give the site url context. Currently 'http','https', 'login', 'login_post', or 'admin'.
 * @return string Site url link with optional path appended.
*/
function site_url($path = '', $scheme = null) {
    // should the list of allowed schemes be maintained elsewhere?
    $orig_scheme = $scheme;
    if ( !in_array($scheme, array('http', 'https')) ) {
        if ( ( 'login_post' == $scheme || 'rpc' == $scheme ) && ( force_ssl_login() || force_ssl_admin() ) )
            $scheme = 'https';
        elseif ( ('login' == $scheme) && ( force_ssl_admin() ) )
            $scheme = 'https';
        elseif ( ('admin' == $scheme) && force_ssl_admin() )
            $scheme = 'https';
        else
            $scheme = ( is_ssl() ? 'https' : 'http' );
    }

    $url = str_replace( 'http://', "{$scheme}://", get_option('siteurl') );

    if ( !empty($path) && is_string($path) && strpos($path, '..') === false )
        $url .= '/' . ltrim($path, '/');

    return apply_filters('site_url', $url, $path, $orig_scheme);
}

/**
 * Retrieve the url to the admin area.
 *
 * @package WordPress
 * @since 2.6.0
 *
 * @param string $path Optional path relative to the admin url
 * @return string Admin url link with optional path appended
*/
function admin_url($path = '') {
    $url = site_url('wp-admin/', 'admin');

    if ( !empty($path) && is_string($path) && strpos($path, '..') === false )
        $url .= ltrim($path, '/');

    return apply_filters('admin_url', $url, $path);
}

/**
 * Retrieve the url to the includes directory.
 *
 * @package WordPress
 * @since 2.6.0
 *
 * @param string $path Optional. Path relative to the includes url.
 * @return string Includes url link with optional path appended.
*/
function includes_url($path = '') {
    $url = site_url() . '/' . WPINC . '/';

    if ( !empty($path) && is_string($path) && strpos($path, '..') === false )
        $url .= ltrim($path, '/');

    return apply_filters('includes_url', $url, $path);
}

/**
 * Retrieve the url to the content directory.
 *
 * @package WordPress
 * @since 2.6.0
 *
 * @param string $path Optional. Path relative to the content url.
 * @return string Content url link with optional path appended.
*/
function content_url($path = '') {
    $scheme = ( is_ssl() ? 'https' : 'http' );
    $url = WP_CONTENT_URL;
    if ( 0 === strpos($url, 'http') ) {
        if ( is_ssl() )
            $url = str_replace( 'http://', "{$scheme}://", $url );
    }

    if ( !empty($path) && is_string($path) && strpos($path, '..') === false )
        $url .= '/' . ltrim($path, '/');

    return apply_filters('content_url', $url, $path);
}

/**
 * Retrieve the url to the plugins directory or to a specific file within that directory.
 * You can hardcode the plugin slug in $path or pass __FILE__ as a second argument to get the correct folder name.
 *
 * @package WordPress
 * @since 2.6.0
 *
 * @param string $path Optional. Path relative to the plugins url.
 * @param string $plugin Optional. The plugin file that you want to be relative to - i.e. pass in __FILE__
 * @return string Plugins url link with optional path appended.
*/
function plugins_url($path = '', $plugin = '') {
    $scheme = ( is_ssl() ? 'https' : 'http' );

    if ( $plugin !== '' && preg_match('#^' . preg_quote(WPMU_PLUGIN_DIR . DIRECTORY_SEPARATOR, '#') . '#', $plugin) ) {
        $url = WPMU_PLUGIN_URL;
    } else {
        $url = WP_PLUGIN_URL;
    }

    if ( 0 === strpos($url, 'http') ) {
        if ( is_ssl() )
            $url = str_replace( 'http://', "{$scheme}://", $url );
    }

    if ( !empty($plugin) && is_string($plugin) ) {
        $folder = dirname(plugin_basename($plugin));
        if ('.' != $folder)
            $url .= '/' . ltrim($folder, '/');
    }

    if ( !empty($path) && is_string($path) && strpos($path, '..') === false )
        $url .= '/' . ltrim($path, '/');

    return apply_filters('plugins_url', $url, $path, $plugin);
}

/**
 * Output rel=canonical for singular queries
 *
 * @package WordPress
 * @since 2.9.0
*/
function rel_canonical() {
    if ( !is_singular() )
        return;

    global $wp_the_query;
    if ( !$id = $wp_the_query->get_queried_object_id() )
        return;

    $link = get_permalink( $id );
    echo "<link rel='canonical' href='$link' />\n";
}

?>