adding download podcast button

if ( ! function_exists( 'jnews_append_podcast_download_button_to_content' ) ) {
    /**
     * Tambahkan tombol download podcast pada akhir konten single post.
     *
     * @param string $content Konten post.
     *
     * @return string
     */
    function jnews_append_podcast_download_button_to_content( $content ) {
        if ( ! is_singular( 'post' ) || ! in_the_loop() || ! is_main_query() ) {
            return $content;
        }

        $post_id               = get_the_ID();
        $jnews_podcast_option = get_post_meta( $post_id, 'jnews_podcast_option', true );
        $enable_podcast       = isset( $jnews_podcast_option['enable_podcast'] ) && '1' === $jnews_podcast_option['enable_podcast'];
        $upload_url           = isset( $jnews_podcast_option['upload'] ) ? $jnews_podcast_option['upload'] : '';

        if ( ! $enable_podcast || empty( $upload_url ) ) {
            return $content;
        }

        $button = sprintf(
            '<div class="jeg_podcast_download_wrapper"><a class="jeg_button jeg_btn_normal" href="%1$s" download target="_blank" rel="noopener">%2$s</a></div>',
            esc_url( $upload_url ),
            esc_html__( 'Download Podcast', 'jnews' )
        );

        return $content . $button;
    }
}

add_filter( 'the_content', 'jnews_append_podcast_download_button_to_content', 999 );