如何为WordPress插件添加站内链接优化功能

/**
 * Plugin Name: Internal Link Optimizer
 * Plugin URI: https://www.example.com
 * Description: A plugin to optimize internal linking for better SEO.
 * Version: 1.0
 * Author: Your Name
 * Author URI: https://www.example.com
 */

// 插件实现代码将在下文介绍

// 添加文章内容过滤钩子
add_filter( 'the_content', 'il_optimizer_add_internal_links' );

function il_optimizer_add_internal_links( $content ) {
    // 获取当前文章的ID
    $post_id = get_the_ID();
    
    // 获取当前文章的关键词
    $keywords = get_post_meta( $post_id, '_il_optimizer_keywords', true );
    
    // 获取随机的两个相关文章
    $related_posts = il_optimizer_get_related_posts( $post_id, $keywords );
    
    // 替换文章内容中的关键词为链接，并添加内部链接
    $content = il_optimizer_replace_keywords( $post_id, $content, $keywords );
    
    // 在文章末尾添加两个相关文章的链接
    $related_links = '';
    foreach ( $related_posts as $post ) {
        $related_links .= '<a href="' . get_permalink( $post->ID ) . '">' . get_the_title( $post->ID ) . '</a> ';
    }
    $content .= '<div class="related-links">' . $related_links . '</div>';
    
    return $content;
}

// 获取相关文章
function il_optimizer_get_related_posts( $post_id, $keywords ) {
    // 根据关键词获取相关文章，此处为示例代码，需根据实际情况进行修改
    $related_posts = get_posts( array(
        'post_type' => 'post',
        'exclude' => $post_id,
        'posts_per_page' => 2,
        's' => $keywords
    ) );
    
    return $related_posts;
}

// 替换文章内容中的关键词为链接
function il_optimizer_replace_keywords( $post_id, $content, $keywords ) {
    // 获取当前文章的URL
    $post_url = get_permalink( $post_id );
    
    // 替换关键词为链接
    $content = str_replace( $keywords, '<a href="' . $post_url . '">' . $keywords . '</a>', $content );
    
    return $content;
}