PHP function to generate social share URLs

social-share-function.php

/**
 * Generate Social Media Buttons
 */
function get_social_share_url( $network, $post_id_to_share, $username=NULL ) {

    $url = '';

    $url_to_share = get_permalink($post_id_to_share);
    $title_to_share = pl_get_the_title($post_id_to_share);
    $summary_to_share = pl_get_the_excerpt($post_id_to_share);

    switch ($network) {
        case 'facebook':
            $url .= 'http://www.facebook.com/sharer/sharer.php?';
            $url .= 's=100&';
            $url .= 'p[url]='.urlencode($url_to_share).'&';
            $url .= 'p[title]='.urlencode($title_to_share).'&';
            $url .= 'p[summary]='.urlencode($summary_to_share).'&';
            $url .= 'u='.urlencode($url_to_share).'&';
            $url .= 't='.urlencode($title_to_share);
            break;

        case 'twitter':
            $url .= 'https://twitter.com/intent/tweet?';
            $url .= 'url='.urlencode($url_to_share).'&';
            $url .= 'text='.urlencode($title_to_share).'&';
            if (isset($username)) {
                $url .= 'via='.$username;
            }
            break;

        case 'linkedin':
            $url .= 'http://www.linkedin.com/shareArticle?';
            $url .= 'mini=true&';
            $url .= 'summary='.urlencode($summary_to_share).'&';
            $url .= 'title='.urlencode($title_to_share).'&';
            $url .= 'url='.urlencode($url_to_share).'&';
            if (isset($username)) {
                $url .= 'source='.$username;
            }
            break;

        case 'pinterest':
            $url .= 'https://www.pinterest.com/pin/create/button/?';
            $url .= 'url='.urlencode($url_to_share).'&';
            $url .= 'description='.urlencode($summary_to_share).'&';
            break;

        default:
            error_log('Please supply a valid network name for function "social_share_url".');
            return false;
            break;
    }

    return $url;

}