Function to generate multiple metaboxes in WordPress - php

Question

I've successfully been able to create one custom metabox for WordPress post types using the following code:
function bandcamp_metabox(){
$posttypes = Array(
'discos',
'Projetos'
);
add_meta_box('bandcamp_link', 'bandcamp link', 'bandcamp_link_meta_callback', $posttypes, 'side');
}
function bandcamp_link_meta_callback( $post ) {
wp_nonce_field('save_bandcamp_link', 'bancamp_meta_box_nonce');
$value = get_post_meta($post->ID,'_bandcamp_link_value_key', true);
echo '<label for="bancamp_link_field">';
echo '<input type="url" id="bancamp_link_field" name="bancamp_link_field" value="' . esc_attr ( $value ) . '" size="25" />';
}
function save_bandcamp_link ( $post_id ) {
if( ! isset( $_POST['bancamp_meta_box_nonce'] ) ){
return;
}
if ( ! wp_verify_nonce( $_POST['bancamp_meta_box_nonce'], 'save_bandcamp_link' ) ){
return;
}
if(defined('DOING_AUTOSAVE') && DOING_AUTOSAVE){
return;
}
if( ! current_user_can( 'edit_post', $post_id ) ){
return;
}
if( ! isset( $_POST['bancamp_link_field'] ) ) {
return;
}
$bandcamp_link = sanitize_text_field( $_POST['bancamp_link_field'] );
update_post_meta($post_id, '_bandcamp_link_value_key', $bandcamp_link);
}
add_action('add_meta_boxes', 'bandcamp_metabox');
add_action('save_post', 'save_bandcamp_link');
I was hoping (still kind of a noob) that through a 'foreach' function I'd be able to re-use the code to create multiple metaboxes at once like this:
$varsocial = Array(
'bandcamp',
'soundcloud',
'facebook',
'instagram',);
foreach($varsocial as $sociallink) {
function social_metabox(){
$posttypes = Array(
'discos',
'Projetos');
add_meta_box(''. $sociallink .'_link', ''. $sociallink .' link', 'social_link_meta_callback', $posttypes, 'side');
}
function social_link_meta_callback( $post ) {
wp_nonce_field('save_social_link', 'social_meta_box_nonce');
$value = get_post_meta($post->ID,'_'. $sociallink .'_link_value_key', true);
echo '<label for="'. $sociallink .'_link_field">';
echo '<input type="url" id="'. $sociallink .'_link_field" name="'. $sociallink .'_link_field" value="' . esc_attr ( $value ) . '" size="25" />';
}
function save_social_link ( $post_id ) {
if( ! isset( $_POST['social_meta_box_nonce'] ) ){
return;
}
if ( ! wp_verify_nonce( $_POST['social_meta_box_nonce'], 'save_social_link' ) ){
return;
}
if(defined('DOING_AUTOSAVE') && DOING_AUTOSAVE){
return;
}
if( ! current_user_can( 'edit_post', $post_id ) ){
return;
}
if( ! isset( $_POST[''. $sociallink .'_link_field'] ) ) {
return;
}
$social_link = sanitize_text_field( $_POST[''. $sociallink .'_link_field'] );
update_post_meta($post_id, '_'. $sociallink .'_link_value_key', $social_link);}
return add_action('add_meta_boxes', 'social_metabox');
return add_action('save_post', 'save_social_link');
}
But such is not working. What am I doing wrong?