Add rotitr

ro-titr.php

<?php
/*
Plugin Name: Rotitr
Description: rotiter add new custom field to post area
Version: 1.0.0
Author: dariushvesal
Author URI: https://vesal.blog
*/

// don't load directly
if (!defined('ABSPATH')) die();

class Rotitr {
  function __construct() {
    add_action('add_meta_boxes', [$this, 'custom_post_field_meta_box']);
    add_action('save_post', [$this, 'save_custom_post_field_meta_box_data']);
    add_action('rotitr', [$this, 'render_rotitr']);
  }


  /**
   * add 	<?php do_action('rotitr'); ?> to single.php to render field
   */
  function render_rotitr() {
    $custom_field_value = get_post_meta(get_the_ID(), '_custom_post_field', true);
    if (!empty($custom_field_value)) {
      // Output the custom field value before the <h1> tag
      echo '<div class="rotitr"><p>' . esc_html($custom_field_value) . '</p></div>';
    }
  }

  function custom_post_field_meta_box() {
    add_meta_box(
      'custom_post_field_meta_box', // Unique ID
      'رو تیتر', // Box title
      [$this, 'custom_post_field_meta_box_callback'], // Content callback function
      'post', // Post type
      'normal', // Context
      'high' // Priority
    );
  }

  function custom_post_field_meta_box_callback($post) {

    // Add a nonce field so we can check for it later
    wp_nonce_field('custom_post_field_meta_box', 'custom_post_field_meta_box_nonce');

    // Get the current value of the custom field
    $custom_field_value = get_post_meta($post->ID, '_custom_post_field', true);

    // Output the field
?>
    <label for="custom_post_field">روتیتر:</label>
    <input type="text" id="custom_post_field" name="custom_post_field" value="<?php echo esc_attr($custom_field_value); ?>" style="width: 100%;" />
<?php
  }

  function save_custom_post_field_meta_box_data($post_id) {
    // Check if our nonce is set.
    if (!isset($_POST['custom_post_field_meta_box_nonce'])) {
      return;
    }

    // Verify that the nonce is valid.
    if (!wp_verify_nonce($_POST['custom_post_field_meta_box_nonce'], 'custom_post_field_meta_box')) {
      return;
    }

    // If this is an autosave, our form has not been submitted, so we don't want to do anything.
    if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) {
      return;
    }

    // Check the user's permissions.
    if (isset($_POST['post_type']) && 'post' == $_POST['post_type']) {
      if (!current_user_can('edit_post', $post_id)) {
        return;
      }
    }

    // Sanitize user input.
    $custom_field_value = isset($_POST['custom_post_field']) ? sanitize_text_field($_POST['custom_post_field']) : '';

    // Update the meta field in the database.
    update_post_meta($post_id, '_custom_post_field', $custom_field_value);
  }
}

new Rotitr();