voce-settings-api.php

<?php
/**
 * A simplification of the settings API
 * @author Michael Pretty (prettyboymp)
 * @version 0.5.3
 */

if(!class_exists('Voce_Settings_API')) {
require_once(dirname(__FILE__).'/display-callbacks.php');
require_once(dirname(__FILE__).'/sanitize-callbacks.php');

class Voce_Settings_API {
	private static $instance;

	private $settings_pages;

	CONST VERSION = '0.5.3';

	/**
	 * Returns singleton instance of api
	 *
	 * @return Voce_Settings_API
	 */
	public static function GetInstance() {
		if(!isset(self::$instance)) {
			self::$instance = new Voce_Settings_API();
		}
		return self::$instance;
	}

	private function __construct() {
		$this->settings_pages = array();
	}

	public function get_setting($setting_key, $group_key, $default = null) {
		if(is_array($setting_group = get_option($group_key)) && isset($setting_group[$setting_key])) {
				return $setting_group[$setting_key];
		} elseif(($group = $this->get_group($group_key)) && isset($group->settings[$setting_key]) && !empty($group->settings[$setting_key]->default_value)) {
			return $group->settings[$setting_key]->default_value;
		}
		return $default;
	}

	public function set_setting($setting_key, $group_key, $value) {
		$new_values = get_option($group_key, array());
		$new_values[$setting_key] = $value;
		update_option($group_key, $new_values);
	}


	private function get_group($group_key) {
		foreach($this->settings_pages as $settings_page) {
			if(isset($settings_page->groups[$group_key])) {
				return $settings_page->groups[$group_key];
			}
		}
		return null;
	}

	/**
	 * Adds a new settings page if one doesn't already exist
	 *
	 * @param string $page_title
	 * @param string $menu_title
	 * @param string $page_key
	 * @param string $capability
	 * @param string $description
	 * @param string $parent_page slug for parent page, leave empty to create new menu
	 * @return Voce_Settings_Page
	 */
	public function add_page($page_title, $menu_title, $page_key, $capability = false, $description = '', $parent_page = '') {
		if(!$capability){
			$capability = 'manage_options';
		} else {
			add_filter('option_page_capability_'.$page_key.'-page', function($old_capability) use ($capability){
				return $capability;
			});
		}

		if(!$page_key) {
			$page_key = 'vsp_'.sanitize_key($this->title);
		}
		if(!isset($this->settings_pages[$page_key])) {
			$page = new Voce_Settings_Page($page_title, $menu_title, $page_key . '-page', $capability, $description, $parent_page);
			$this->settings_pages[$page_key] = $page;
		}
		return $this->settings_pages[$page_key];
	}
}

class Voce_Settings_Page {

	public $title;
	public $menu_title;
	public $page_key;
	public $capability;
	public $description;

	/**
	 * Key of this page's parent page if it is a submenu item
	 *
	 * @var string
	 */
	public $parent_page;
	public $groups;


	public function __construct($title, $menu_title, $page_key, $capability = 'manage_options', $description = '', $parent_page = '') {
		$this->title = $title;
		$this->page_key = $page_key;
		$this->menu_title = $menu_title;
		$this->capability = $capability;
		$this->description = $description;
		$this->parent_page = $parent_page;
		$this->groups = array();

		add_action('admin_menu', array($this, 'admin_menu'));
		if(current_user_can($this->capability)) {
			add_action('admin_init', array($this, 'admin_init'));
		}
	}

	public function add_error($code, $message, $type = 'error') {
			add_settings_error($this->page_key, $code, $message, $type);
	}

	/**
	 * Adds a new group to the page
	 *
	 * @param string $group_key
	 * @param string $title
	 * @param string $capability
	 * @param string $description
	 * @return Voce_Settings_Group
	 */
	public function add_group($title, $group_key, $capability = '', $description = '') {
		if(!isset($this->groups[$group_key])) {
			$group = new Voce_Settings_Group($this, $title, $group_key, $capability, $description);
			$this->groups[$group_key] = $group;
		}
		return $this->groups[$group_key];
	}

	public function admin_menu() {
		if(current_user_can($this->capability)) {
			//only add the page if groups exist
			if($this->parent_page) {
				$page_hook = add_submenu_page($this->parent_page, $this->title, $this->menu_title, $this->capability, $this->page_key, array($this, 'display'));
			} else {
				$page_hook = add_menu_page($this->title, $this->menu_title, $this->capability, $this->page_key, array($this, 'display'));
			}

			$page = $this;

			add_action( 'load-' . $page_hook, function() use ($page){
				do_action( 'vs_admin_enqueue_scripts', $page );
			} );
		}
	}

	public function admin_init() {
		register_setting($this->page_key, $this->page_key, array($this, 'sanitize_callback'));
	}

	public function sanitize_callback($new_values) {
		if(current_user_can($this->capability)) {
			$this->add_error('all', 'Your changes have been saved.', 'updated');

			foreach($this->groups as $group) {
				$new_value = isset($new_values[$group->group_key]) ? $new_values[$group->group_key] : array();
				$group->sanitize_callback($new_value);
			}
		}
		/**
		 * return false so a new option doesn't get added for this.
		 */
		return false;
	}

	public function display() {
		if(current_user_can($this->capability)) {
			?>
			<div class="wrap">
				<h2><?php echo wp_kses_post( $this->title); ?></h2>
				<?php settings_errors($this->page_key, false, true); ?>
				<?php if($this->description) { echo sprintf('<p>%s</p>', wp_kses_post( $this->description ) ); } ?>
				<form action="options.php" method="POST">
					<?php settings_fields($this->page_key); ?>
					<?php do_settings_sections($this->page_key); ?>
					<p class="submit">
						<input type="submit" value="Save Changes" class="button-primary" name="Submit">
					</p>
				</form>
			</div>
			<?php
		}
	}
}

class Voce_Settings_Group {
	/**
	 * Pointer to this Section's Page
	 *
	 * @var Voce_Settings_Page
	 */
	public $page;

	public $title;
	public $capability;
	public $group_key;
	public $description;
	public $settings;

	public function __construct($page, $title, $group_key, $capability = '', $description = '') {
		$this->page = $page;
		$this->group_key = $group_key;
		$this->title = $title;
		$this->capability = $capability ? $capability : $this->page->capability;
		$this->description = $description;
		$this->settings = array();
		if(current_user_can($this->capability)) {
			add_action('admin_init', array($this, 'admin_init'));
		}
	}

	public function add_error($code, $message, $type = 'error') {
			$this->page->add_error($code, $message, $type);
	}


	public function admin_init() {
			add_settings_section($this->group_key, $this->title, array($this, 'display'), $this->page->page_key);
	}

	/**
	 * Adds a setting to the group
	 *
	 * @param string $title
	 * @param string $setting_key
	 * @param array $args
	 * @return Voce_Setting
	 */
	public function add_setting($title, $setting_key, $args = array()) {
		if(!isset($this->settings[$setting_key])) {
			$setting = new Voce_Setting($this, $title, $setting_key, $args);
			$this->settings[$setting_key] = $setting;
		}
		return $this->settings[$setting_key];
	}

	public function display() {
		if(current_user_can($this->capability)) {
			if ( $this->description ) { echo sprintf( '<p>%s</p>', wp_kses_post( $this->description ) ); }
		}
	}

	public function sanitize_callback($new_values) {
		$old_values = get_option($this->group_key, array());
		if(current_user_can($this->capability)) {
			foreach($this->settings as $setting) {
				$new_value = isset($new_values[$setting->setting_key]) ? $new_values[$setting->setting_key] : null;
				$old_value = isset($old_values[$setting->setting_key]) ? $old_values[$setting->setting_key] : null;
				$old_values[$setting->setting_key] = $setting->sanitize($new_value, $old_value);
			}
		}
		update_option($this->group_key, $old_values);
	}
}

class Voce_Setting {

	/**
	 * Pointer to this settings group
	 *
	 * @var Voce_Settings_Group
	 */
	public $group;
	public $title;
	public $setting_key;
	public $capability;
	public $default_value;
	public $args;

	/**
	 * Constructor for Voce Setting
	 *
	 * @param Voce_Settings_Group $group
	 * @param string $title
	 * @param string $setting_key
	 * @param array $args
	 */
	public function __construct($group, $title, $setting_key, $args = array()) {
		$this->group = $group;
		$this->title = $title;
		$this->setting_key = $setting_key;

		$args = wp_parse_args($args, $defaults = array(
			'capability' => $this->group->capability,
			'default_value' => '',
			'display_callback' => '',
			'sanitize_callbacks' => array('vs_sanitize_text'),
			'description' => ''
			));

		$this->default_value = $args['default_value'];
		$this->capability = $args['capability'];
		$this->args = $args;
		if(current_user_can($this->capability)) {
			add_action('admin_init', array($this, 'admin_init'));
		}
	}

	public function add_error($message, $type = 'error') {
		$this->group->add_error($this->setting_key, $message, $type);
	}

	public function admin_init() {
		$field_id = implode('-', array($this->group->page->page_key, $this->group->group_key, $this->setting_key));
		add_settings_field($this->setting_key, sprintf('<label for="%s">%s</label>', esc_attr( $field_id ), wp_kses_post( $this->title ) ), array($this, 'display'), $this->group->page->page_key, $this->group->group_key);
	}

	public function get_field_name() {
		return $this->group->page->page_key . '[' . $this->group->group_key . '][' . $this->setting_key . ']';
	}

	public function get_field_id() {
		return $this->group->page->page_key . '-' . $this->group->group_key . '-' . $this->setting_key;
	}

	public function display() {
		$value = Voce_Settings_API::GetInstance()->get_setting($this->setting_key, $this->group->group_key, $this->default_value);
		if(!empty($this->args['display_callback'])) {
			call_user_func_array($this->args['display_callback'], array($value, $this, $this->args));
		} else {
			// default to text field
			vs_display_text_field($value, $this, $this->args);
		}
	}

	public function sanitize($new_value, $old_value) {
		if(current_user_can($this->capability)) {
			$old_value = $new_value;
			foreach($this->args['sanitize_callbacks'] as $callback) {
				$old_value = call_user_func_array($callback, array($old_value, $this, $this->args));
			}
		}
		return $old_value;
	}
}

}