Sindbad~EG File Manager

<?php
/**
 * Master Slider Admin
 *
 * @package   MasterSlider
 * @author    averta [averta.net]
 * @license   LICENSE.txt
 * @link      https://masterslider.com
 * @copyright Copyright © 2014 averta
 */

// no direct access allowed
if ( ! defined( 'ABSPATH' ) ) {
    die();
}


/**
 * This class is used to work with the
 * administrative side of Masterslider
 */
class Master_Slider_Admin {

  /**
   * Instance of this class.
   *
   * @since    1.0.0
   *
   * @var      object
   */
  protected static $instance = null;

  /**
   * Slug of the plugin screen.
   *
   * @since    1.0.0
   *
   * @var      string
   */
  protected $sliders_screen_hook_suffix = null;



  /**
   * Initialize the plugin by loading admin classes and functions
   *
   * @since     1.0.0
   */
  private function __construct() {

    // include admin files
    $this->includes();

    add_action( 'init', array( $this, 'init' ) );
  }


  /**
   * Include admin essential classes and functions
   *
   * @return void
   */
  private function includes(){
    include_once( MSWP_AVERTA_ADMIN_DIR . '/includes/index.php' );
    include_once( MSWP_AVERTA_ADMIN_DIR . '/views/setting/class-msp-settings.php' );
  }


  public function init() {

    // Before init action
    do_action( 'before_masterslider_admin_init' );

    // A filter hook to restrict access to plugin panel only for super admin on multiste
    if( apply_filters( 'masterslider_access_only_for_super_admins' , 0 ) && ! is_super_admin() ) {
      return;
    }

    // Assign masterslider custom capabilities
    Master_Slider::assign_custom_caps();
    // Inject default styles and effects
    Master_Slider::set_default_options();


    // Initial tasks on admin init
    add_action( 'admin_init', array( $this, 'admin_init') );

    // Load admin Stylesheet and JavaScript.
    add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_scripts') );

    // Add the options page and menu item.
    add_action( 'admin_menu', array( $this, 'add_plugin_admin_menu' ) );

    // Add an action link pointing to the setting page.
    add_filter( 'plugin_action_links_'. MSWP_AVERTA_BASE_NAME, array( $this, 'add_action_links' ) );

    // Add an action link on plugin row meta in plugins page
    add_filter( 'plugin_row_meta', array( $this, 'plugin_row_meta' ), 10, 4 );

    // Admin init action
    do_action( 'masterslider_admin_init' );
  }


  /**
   * Triggers on admin init
   *
   * @return void
   */
  public function admin_init(){

    $this->after_plugin_update();
  }


  /**
   * Regenerate and cache custom css codes for all slider after plugin update
   *
   * @return bool  TRUE on success, FALSE otherwise
   */
  public function after_plugin_update (){

    if( get_option( 'masterslider_lite_plugin_version', '0' ) == MSWP_AVERTA_VERSION )
      return false;

    msp_save_custom_styles();
    // msp_flush_all_sliders_cache(); 2.0.0
    update_option( 'masterslider_lite_plugin_version', MSWP_AVERTA_VERSION );
    do_action( 'masterslider_after_plugin_updated' );

    return true;
  }


  /**
   * Return an instance of this class.
   *
   * @since     1.0.0
   *
   * @return    object    A single instance of this class.
   */
  public static function get_instance() {

    if( apply_filters( 'masterslider_access_only_for_super_admins' , 0 ) && ! is_super_admin() ) {
      return;
    }

    // If the single instance hasn't been set, set it now.
    if ( null == self::$instance ) {
      self::$instance = new self;
    }

    return self::$instance;
  }


  /**
   * Register and enqueue admin-specific JavaScript & Stylesheet.
   *
   * @since     1.0.0
   *
   * @return    null    Return early if no settings page is registered.
   */
  public function enqueue_admin_scripts() {

    $admin_assets = new MSP_Admin_Assets();
    $admin_assets->enqueue_global_assets();

    if ( ! isset( $this->sliders_screen_hook_suffix ) )
        return;

    // load masterslider spesific assets only on it's admin page
    $screen = get_current_screen();
    if ( $this->sliders_screen_hook_suffix == $screen->id ) {
        $admin_assets->enqueue_panel_assets();

        if ( isset( $_REQUEST['slider_id'] ) && is_numeric( $_REQUEST['slider_id'] ) ) {

          $slider_id  = sanitize_text_field( $_REQUEST['slider_id'] );
          global $mspdb;
          $custom_fonts = $mspdb->get_slider_field_val( $slider_id, 'custom_fonts' );

          if ( ! empty( $custom_fonts ) )
            wp_enqueue_style( 'master-slider-admin-fonts', 'http://fonts.googleapis.com/css?family=' . $custom_fonts, [], false, 'all' );
        }
    }

    if ( MSWP_SLUG . '_page_' . MSWP_SLUG . '-setting' == $screen->id ) {
        $admin_assets->enqueue_setting_page_assets();
    }

  }


  /**
   * Register the administration menu for this plugin into the WordPress Dashboard menu.
   *
   * @since    1.0.0
   */
  public function add_plugin_admin_menu() {

    $ms_page_title = apply_filters( 'masterslider_admin_page_title', __( 'Master Sliders', 'master-slider' ) );
    $ms_menu_title = apply_filters( 'masterslider_admin_menu_title', __( 'Master Slider' , 'master-slider' ) );

    // Add a top-level menu for master slider
    $this->sliders_screen_hook_suffix = add_menu_page(
      $ms_page_title,
      $ms_menu_title,
      apply_filters( 'masterslider_access_capability', 'access_masterslider' ),
      MSWP_SLUG,
      array( $this, 'display_master_slider_panel_page' )
    );

  }


  /**
   * Render the panel page for this plugin.
   *
   * @since    1.0.0
   */
  public function display_master_slider_panel_page() {
    include_once( 'views/index.php' );
  }


  /**
   * Add settings action link to the plugins page.
   *
   * @since    1.2.0
   */
  public function add_action_links( $links ) {

    $links['settings'] = '<a href="' . admin_url( 'admin.php?page=' . MSWP_SLUG . '-setting' ) . '">' . __( 'Settings', 'master-slider' ) . '</a>';
    $links['go_pro']   = '<a href="https://avt.li/mslgo">' . __( 'Go Pro', 'master-slider' ) . '</a>';

    return $links;
  }


  /**
   * Add extra action link to the plugin meta on plugins page.
   *
   * @since    1.8.0
   */
  public function plugin_row_meta( $plugin_meta, $plugin_file, $plugin_data, $status ){
    if( $plugin_file == MSWP_AVERTA_BASE_NAME ) {  }
    return $plugin_meta;
  }


}

return Master_Slider_Admin::get_instance();