Custom meta boxes array not saving data

Hi, I am working on a demo project and have been stuck in this stage for past few hours. I intend to create a custom post with custom meta fields which will save my contact details. I followed an tutorial on how to create multiple fields at once using array. Everything is nicely done and showing all the fields, however I can not get to show data entered in the custom fields. I am posting my code to show where am I doing wrong? I really need this to work so any help would be super welcome.
Thanks in advance.
The code

<?php
function contact_details(){
  $labels = array(
    'name' => _x('Contact', 'post type general name'),
    'singular_name' => _x('Contact Details', 'post type singular_name'),
    'add_new' => _x('Add New', 'item'),
    'add_new_item' => __('Add New Item'),
    'edit_item' => __('Edit Item'),
    'new_item' => __('New Item'),
    'view_item' => __('View Item'),
    'search_items' => __('Search'),
    'not_found' => __('Nothing found'),
    'not_found_in_trash' => __('Nothing found in trash'),
    'parent_item_colon' => ''
    );

  $args = array(
    'labels' => $labels,
    'public' => true,
    'publicly_queryable' => true,
    'show_ui' => true,
    'query_var' => true,
    'rewrite' => true,
    'capability_type' => 'post',
    'hierarchical' => false,
    'menu_position' => 6,
    'taxonomies' => array('category'),
    'supports' => array('title', 'thumbnail')

    );

  register_post_type('contacts', $args);
  flush_rewrite_rules();

}
add_action('init', 'contact_details');

function contact_meta_box(){
  add_meta_box(
    'contact_details_meta_box',
    'Add Contact Deatils',
    'show_contact_meta_box',
    'contacts',
    'normal',
    'high'
    );
}

add_action('add_meta_boxes', 'contact_meta_box');

// field array
$prefix = 'custom';
$custom_meta_fields = array(
  array(
    'label' => 'Mail',
    'desc' => 'enter email address',
    'id' => $prefix.'mail',
    'type' => 'email'
    ),
  array(
    'label' => 'Contact Number',
    'desc' => 'enter contact number',
    'id' => $prefix.'text',
    'type' => 'text'
    ),
  array(
    'label' => 'Address',
    'desc' => 'enter address',
    'id' => $prefix.'text',
    'type' => 'textarea'
    ),
  array(
    'label' => 'Skype name',
    'desc' => 'enter skype name',
    'id' => $prefix.'text',
    'type' => 'text'
    ),
  );

function show_contact_meta_box(){
  global $custom_meta_fields, $contacts;

  echo '
<ul>';
  foreach ($custom_meta_fields as $field){
    $meta = get_post_meta($post->ID, $field['id'], true);

    echo ' <label for="'.$field['id'].'">'. $field['label']. '</label>
<li>';
    switch($field['type']){

      case'email':
      echo '<input type="email" name="'.$field['id'].'" id="'.$field['id'].'" value="'.$meta.'">

        <span class="desc">'.$field['desc'].'</span>';
        break;

        case'text':
        echo '<input type="text" name="'.$field['id'].'" id="'.$field['id'].'" value="'.$meta.'">

        <span class="desc">'.$field['desc'].'</span>';
        break;

        case'textarea':
        echo '<textarea name="'.$field['id'].'" id="'.$field['id'].'">'.$meta.'</textarea>

        <span class="desc">'.$field['desc'].'</span>';
        break;
    }
    echo '</li>
';
  }
echo '</ul>
';
}

function save_custom_meta($post_id){
  global $custom_meta_fields;

  if('contacts' == $_POST['post_type']){

    if ( !current_user_can( 'edit_post', $post_id ) )
        return $post_id;
  }
  else
  {
    if ( !current_user_can( 'edit_post', $post_id ) )
        return $post_id;
  }

  foreach($custom_meta_fields as $field){
    $old = get_post_meta($post_id, $field['id'], true);
    $new = $_POST[$field['id']];

    if($new && $new != $old){
      update_post_meta($post_id, $field['id'], $new);
    } elseif ('' == $new && $old) {
            delete_post_meta($post_id, $field['id'], $old);
        }
  }
}

add_action('save_post', 'save_custom_meta');
?>