<?php

/**
 * LayerSlider Slider Revisions Class
 *
 * Utility class to manage slider revisions and revert sliders back to earlier states.
 *
 * @since 6.3.0
 * @author John Gera
 * @copyright Copyright (c) 2017  John Gera, George Krupa, and Kreatura Media Kft.
 * @license http://codecanyon.net/licenses/faq Envato marketplace licenses
 */

class LS_Revisions {

	public static $active 	= false;
	public static $enabled 	= true;
	public static $limit 	= 100;
	public static $interval = 10;


	/**
	 * Private constructor to prevent instantiate static class
	 *
	 * @since 6.3.0
	 * @access private
	 * @return void
	 */
	private function __construct() {

	}




	public static function init() {
		if( get_option('layerslider-authorized-site', false) &&
			get_option('ls-revisions-enabled', true) ) {
				self::$active = true;
		}

		$option 		= get_option('ls-revisions-enabled', true);
		self::$enabled 	= ! empty( $option );
		self::$limit 	= get_option('ls-revisions-limit', 100);
		self::$interval = get_option('ls-revisions-interval', 10);
	}





	/**
	 * Counts the number of revisions saved for the specified slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @return int The number of revisions available for the slider
	 */
	public static function count( $sliderId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ) {
			return false;
		}

		$result = $wpdb->get_col( $wpdb->prepare("
			SELECT COUNT(*) FROM {$wpdb->prefix}layerslider_revisions
			WHERE slider_id = %d
			LIMIT 1
		", $sliderId));


		return (int) $result[0];
	}





	/**
	 * Finds and returns revisions for a specified slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @return array Array of found slider revisions, or false on error
	 */
	public static function snapshots( $sliderId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ) {
			return false;
		}

		return $wpdb->get_results( $wpdb->prepare("
			SELECT * FROM {$wpdb->prefix}layerslider_revisions
			WHERE slider_id = %d
			ORDER BY id ASC
			LIMIT 500
		", $sliderId));
	}





	/**
	 * Retrieve a specific revision by its database ID
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $revisionId The revision database ID
	 * @return object The chosen revision data, or false on error
	 */
	public static function get( $revisionId ) {

		global $wpdb;
		$revisionId = (int)$revisionId;

		if( empty( $revisionId ) || ! is_numeric($revisionId) ) {
			return false;
		}

		return $wpdb->get_row( $wpdb->prepare("
			SELECT * FROM {$wpdb->prefix}layerslider_revisions
			WHERE id = %d
			ORDER BY id ASC
			LIMIT 1
		", $revisionId));
	}





	/**
	 * Retrieve the last revision for a particular slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @return object The last revision, or false on error
	 */
	public static function last( $sliderId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ) {
			return false;
		}

		return $wpdb->get_row( $wpdb->prepare("
			SELECT * FROM {$wpdb->prefix}layerslider_revisions
			WHERE slider_id = %d
			ORDER BY id DESC
			LIMIT 1
		", $sliderId));
	}





	/**
	 * Adds a new revision for a specified slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @param string $sliderData The serialized data of the slider
	 * @return array Array of found slider revisions, or false on error
	 */
	public static function add( $sliderId, $sliderData ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) || empty( $sliderData ) )  {
			return false;
		}

		$wpdb->insert( $wpdb->prefix.'layerslider_revisions',
			array(
				'slider_id' => $sliderId,
				'author' => get_current_user_id(),
				'data' => $sliderData,
				'date_c' => time()
			),
			array(
				'%d',
				'%d',
				'%s',
				'%d'
			)
		);

		return $wpdb->insert_id;
	}





	/**
	 * Removes a revision
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $revisionId The revision database ID
	 * @return mixed Returns the number of rows affected, or false on error
	 */
	public static function remove( $revisionId ) {

		global $wpdb;
		$revisionId = (int)$revisionId;

		if( empty( $revisionId ) || ! is_numeric($revisionId) ) {
			return false;
		}

		return $wpdb->delete( $wpdb->prefix.'layerslider_revisions',
			array( 'id' => $revisionId ),
			array( '%d' )
		);
	}




	/**
	 * Removes the last revision of the specified slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The revision database ID
	 * @return mixed Returns the number of rows affected, or false on error
	 */
	public static function shift( $sliderId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ) {
			return false;
		}

		return $wpdb->query( $wpdb->prepare("
			DELETE FROM {$wpdb->prefix}layerslider_revisions
			WHERE slider_id = %d
			ORDER BY id ASC
			LIMIT 1
		", $sliderId ) );
	}




	/**
	 * Removes all revisions for a chosen slider
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @return mixed Returns the number of rows affected, or false on error
	 */
	public static function clear( $sliderId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ) {
			return false;
		}

		return $wpdb->delete( $wpdb->prefix.'layerslider_revisions',
			array( 'slider_id' => $sliderId ),
			array( '%d' )
		);
	}





	/**
	 * Truncates the entire database table.
	 *
	 * @since 6.3.0
	 * @access public
	 * @return mixed Returns the number of rows affected, or false on error
	 */
	public static function truncate( ) {

		global $wpdb;

		return $wpdb->query("TRUNCATE {$wpdb->prefix}layerslider_revisions;");
	}





	/**
	 * Reverts the specified slider to a chosen revision
	 *
	 * @since 6.3.0
	 * @access public
	 * @param int $sliderId The slider database ID
	 * @param int $revisionId The revision database ID
	 * @return bool True on success, false on error
	 */
	public static function revert( $sliderId, $revisionId ) {

		global $wpdb;
		$sliderId = (int)$sliderId;
		$revisionId = (int)$revisionId;

		if( empty( $sliderId ) || ! is_numeric($sliderId) ||
			empty( $revisionId )|| ! is_numeric($revisionId) ) {
			return false;
		}


		$slider 	= LS_Sliders::find( $sliderId );
		$revision 	= self::get( $revisionId );
		$data 		= $revision->data;

		if( $revision &&  $data ) {
			self::add( $sliderId, $data );
			LS_Sliders::update( $sliderId, $slider['name'], json_decode($data, true), $slider['slug']);
		}

		return true;
	}
}

