Generates social sharing icons and links for single posts and WooCommerce products.

functions.php

<?php
/**
 * Generates social sharing icons and links for posts and products.
 * 
 * For best results, make sure your site already includes OpenGraph support. 
 * @link https://ogp.me/
 */
function textdomain_social_sharing() {
    
    //Set up the sharing links. We're keeping it basic - Facebook, Twitter, and Pinterest.
    $sharing_services = array(
        'facebook'      => esc_url( 'https://www.facebook.com/sharer/sharer.php' ),
        'twitter'       => esc_url( 'https://twitter.com/intent/tweet' ),
        'pinterest'     => esc_url( 'https://www.pinterest.com/pin/create/button/' )
    );

    //Get the post content to share and set default values.
    $post_excerpt = wp_strip_all_tags( get_the_excerpt() );
    $share_content = array(
        'text'          => rawurlencode( esc_html( 'Check out what I found at ' . get_bloginfo( 'name' ) . '.' ) ),
        'url'           => rawurlencode( get_permalink() ),
        'description'   => $post_excerpt ? rawurlencode( $post_excerpt ) : rawurlencode( get_the_title() ),
        'image-src'     => ''
    );
    
    // Make sure we're appending to the sharer from single posts and products only, no pages. 
    // Changing default values where necessary.   
    if( class_exists( 'WooCommerce' ) && is_product() ) :
        /**
         * Probably do not need to do this, but WooCommerce template functions uses this same method to grab the main
         * product image for single products.
         * 
         * @see woocommerce/templates/single-product/product-image.php
         * @see woocommerce/includes/wc-template-functions.php:1552
         */
        
        global $product; 
        $product_thumbnail_id = $product->get_image_id();
        $share_content[ 'image-src' ] = $product_thumbnail_id ? rawurlencode( wp_get_attachment_url( $product_thumbnail_id ) ) : rawurlencode( wc_placeholder_img_src( 'woocommerce_single' ) );

    elseif( is_single() ) :

        $share_content[ 'image-src' ] = has_post_thumbnail() ? rawurlencode( wp_get_attachment_url( get_post_thumbnail_id() )) : rawurlencode( get_template_directory_uri() . '/path/to/alternate/image.jpg' );
    
    endif;

    // Build the markup for the sharing services component. This will hold all buttons.
    $share_buttons = '<div class="social-sharing-buttons"><p>Share this:</p>';

    // Class arary for social sharing links.
    $share_class[] = '';

    // Array for query args to append to the url.
    $query_args[] = '';

    // Build the sharing services link markup to append to the sharing services component.
    foreach( $sharing_services as $service_key => $service_url ) :
        //Assign CSS classes for each service.
        $share_class[$service_key] = $service_key . '-share-btn';
        //Initialize query args for each service as empty array.
        $query_args[$service_key] = [];

        //For each sharing service by key.
        switch( $service_key ) :
            case 'facebook':
                //Assign it's specific query arguments.
                $query_args[$service_key] = [
                    'u'     => $share_content['url'],
                ];
                //Append the sharing service button to the markup.
                $share_buttons .= '<a href="' . esc_url( add_query_arg( $query_args[$service_key], $service_url ) ) . '" class="' . $share_class[$service_key] . '" aria-label="' . esc_attr__( 'Share to Facebook', 'textdomain' ) . '" rel="nofollow noopener" target="_blank"></a>';
                break; 
            case 'twitter':
                $query_args[$service_key] = [
                    'text'      => $share_content['text'],
                    'url'       => $share_content['url'],
                ];
                $share_buttons .= '<a href="' . esc_url( add_query_arg( $query_args[$service_key], $service_url ) ) . '" class="' . $share_class[$service_key] . '" aria-label="' . esc_attr__( 'Share to Twitter', 'textdomain' ) . '" rel="nofollow noopener" target="_blank"></a>';
                break;
            case 'pinterest':
                $query_args[$service_key] = [
                   'url'            => $share_content['url'],
                   'media'          => $share_content['image-src'],
                   'description'    => $share_content['description'],
                ];
                $share_buttons .= '<a href="' . esc_url( add_query_arg( $query_args[$service_key], $service_url ) ) . '" class="' . $share_class[$service_key] . '" aria-label="' . esc_attr__( 'Pin to Pinterest', 'textdomain' ) . '" rel="nofollow noopener" target="_blank"></a>';
                break;
        endswitch;

    endforeach;
	//Close the share buttons markup.
    $share_buttons .= '</div>';
    //Return the share buttons for display.
    echo $share_buttons;

}

For best results, make sure your site includes OpenGraph support.
Call the function in your single posts template and WooCommerce share.php file using add_action( 'woocommerce_share', 'textdomain_social_sharing' );

Style your sharing links using the ::before CSS pseudo element, as in .facebook-share-btn::before { content: "<icon font unicode>"; }. Or you can add the icon font markup to the individual share link markup.