Adds new fields to audio player

audio-ext.php

<?php
// Hook into the attachment fields
add_filter('attachment_fields_to_edit', 'add_custom_audio_fields', 10, 2);
add_filter('attachment_fields_to_save', 'save_custom_audio_fields', 10, 2);

// Function to add custom fields
function add_custom_audio_fields($form_fields, $post) {
    // Only show these fields for audio files
    if ($post->post_mime_type == 'audio/mpeg' || $post->post_mime_type == 'audio/wav' || $post->post_mime_type == 'audio/ogg') {
        // Record Label field
        $form_fields['record_label'] = [
            'label' => 'Record Label',
            'input' => 'text',
            'value' => get_post_meta($post->ID, 'record_label', true),
            'helps' => 'Enter the record label of the audio file.'
        ];
        
        // Artist field
        $form_fields['artist'] = [
            'label' => 'Artist',
            'input' => 'text',
            'value' => get_post_meta($post->ID, 'artist', true),
            'helps' => 'Enter the artist name of the audio file.'
        ];

        // Year field
        $form_fields['year'] = [
            'label' => 'Year',
            'input' => 'text',
            'value' => get_post_meta($post->ID, 'year', true),
            'helps' => 'Enter the release year of the audio file.'
        ];
    }

    return $form_fields;
}

// Function to save custom fields
function save_custom_audio_fields($post, $attachment) {
    if (isset($attachment['record_label'])) {
        update_post_meta($post['ID'], 'record_label', sanitize_text_field($attachment['record_label']));
    }
    
    if (isset($attachment['artist'])) {
        update_post_meta($post['ID'], 'artist', sanitize_text_field($attachment['artist']));
    }

    if (isset($attachment['year'])) {
        update_post_meta($post['ID'], 'year', sanitize_text_field($attachment['year']));
    }

    return $post;
}

// Add the shortcode to display audio metadata
function display_audio_meta_shortcode($atts) {
    // Fetch current post ID
    $post_id = get_the_ID();

    // Fetch audio metadata
    $record_label = get_post_meta($post_id, 'record_label', true);
    $artist = get_post_meta($post_id, 'artist', true);
    $year = get_post_meta($post_id, 'year', true);

    // Start output buffering
    ob_start();

    // Check if there's any audio metadata available
    if ($record_label || $artist || $year) {
        echo '<div class="audio-meta">';
        
        // Display Record Label
        if ($record_label) {
            echo '<p><strong>Record Label:</strong> ' . esc_html($record_label) . '</p>';
        }
        
        // Display Artist
        if ($artist) {
            echo '<p><strong>Artist:</strong> ' . esc_html($artist) . '</p>';
        }

        // Display Year
        if ($year) {
            echo '<p><strong>Year:</strong> ' . esc_html($year) . '</p>';
        }

        echo '</div>';
    }

    // Return the buffered output
    return ob_get_clean();
}
add_shortcode('audio_meta', 'display_audio_meta_shortcode');