<?php
defined( 'ABSPATH' ) || exit;

/**
 * Handle add-on licenses
 */
class Advanced_Ads_Admin_Licenses {
	/**
	 * Instance of this class.
	 *
	 * @var      object
	 */
	protected static $instance = null;

	/**
	 * Advanced_Ads_Admin_Licenses constructor.
	 */
	private function __construct() {
		if ( ! defined( 'DOING_AJAX' ) ) {
			add_action( 'load-plugins.php', array( $this, 'check_plugin_licenses' ) );
		}
		add_action( 'plugins_loaded', array( $this, 'wp_plugins_loaded' ) );

		// todo: check if this is loaded late enough and all add-ons are registered already.
		add_filter( 'upgrader_pre_download', array( $this, 'addon_upgrade_filter' ), 10, 3 );
	}

	/**
	 * Actions and filter available after all plugins are initialized
	 */
	public function wp_plugins_loaded() {

		// check for add-on updates.
		add_action( 'admin_init', array( $this, 'add_on_updater' ), 1 );
	}

	/**
	 * Return an instance of this class.
	 *
	 * @return self   object    A single instance of this class.
	 */
	public static function get_instance() {
		// If the single instance hasn't been set, set it now.
		if ( null === self::$instance ) {
			self::$instance = new self();
		}

		return self::$instance;
	}

	/**
	 * Initiate plugin checks
	 *
	 * @since 1.7.12
	 */
	public function check_plugin_licenses() {

		if ( is_multisite() ) {
			return;
		}

		// gather all add-on plugin files.
		$add_ons = apply_filters( 'advanced-ads-add-ons', array() );
		foreach ( $add_ons as $_add_on ) {

			// check license status.
			if ( $this->get_license_status( $_add_on['options_slug'] ) !== 'valid' ) {
				// register warning.
				$plugin_file = plugin_basename( $_add_on['path'] );
				add_action( 'after_plugin_row_' . $plugin_file, array( $this, 'add_plugin_list_license_notice' ), 10, 3 );
			}
		}
	}

	/**
	 * Add a row below add-ons with an invalid license on the plugin list
	 *
	 * @param string $plugin_file Path to the plugin file, relative to the plugins directory.
	 * @param array  $plugin_data An array of plugin data.
	 * @param string $status Status of the plugin. Defaults are 'All', 'Active',
	 *                            'Inactive', 'Recently Activated', 'Upgrade', 'Must-Use',
	 *                            'Drop-ins', 'Search'.
	 *
	 * @since 1.7.12
	 * @todo make this work on multisite as well
	 */
	public function add_plugin_list_license_notice( $plugin_file, $plugin_data, $status ) {

		echo '<tr class="advads-plugin-update-tr plugin-update-tr active"><td class="plugin-update colspanchange" colspan="3"><div class="update-message notice inline notice-warning notice-alt"><p>'
		     . sprintf( __( 'There might be a new version of %1$s. Please <strong>provide a valid license key</strong> in order to receive updates and support <a href="%2$s">on this page</a>.', 'advanced-ads' ), $plugin_data['Title'], admin_url( 'admin.php?page=advanced-ads-settings#top#licenses' ) )
		     . '</p></div></td></tr>';

	}


	/**
	 * Save license key
	 *
	 * @param string $addon string with add-on identifier.
	 * @param string $plugin_name name of the add-on.
	 * @param string $options_slug slug of the option in the database.
	 * @param string $license_key license key.
	 *
	 * @return string
	 * @since 1.2.0
	 */
	public function activate_license( $addon = '', $plugin_name = '', $options_slug = '', $license_key = '' ) {

		if ( '' === $addon || '' === $plugin_name || '' === $options_slug ) {
			return __( 'Error while trying to register the license. Please contact support.', 'advanced-ads' );
		}

		$license_key = esc_attr( trim( $license_key ) );
		if ( '' === $license_key ) {
			return __( 'Please enter a valid license key', 'advanced-ads' );
		}

		if ( has_filter( 'advanced_ads_license_' . $options_slug ) ) {
			return apply_filters( 'advanced_ads_license_' . $options_slug, false, __METHOD__, $plugin_name, $options_slug, $license_key );
		}

		/**
		 * We need to remove the mltlngg_get_url_translated filter added by Multilanguage by BestWebSoft, https://wordpress.org/plugins/multilanguage/
		 * it causes the URL to look much different than it originally is
		 * we are adding it again later
		 */
		remove_filter( 'home_url', 'mltlngg_get_url_translated' );

		$api_params = array(
			'edd_action' => 'activate_license',
			'license'    => $license_key,
			'item_name'  => urlencode( $plugin_name ),
			'url'        => home_url(),
		);

		/**
		 * Re-add the filter removed from above
		 */
		if ( function_exists( 'mltlngg_get_url_translated' ) ) {
			add_filter( 'home_url', 'mltlngg_get_url_translated' );
		}

		// Call the custom API.
		$response = wp_remote_post(
			ADVADS_URL,
			array(
				'timeout'   => 15,
				'sslverify' => false,
				'body'      => $api_params,
			)
		);

		// show license debug output if constant is set.
		if ( defined( 'ADVANCED_ADS_SHOW_LICENSE_RESPONSE' ) ) {
			return '<pre>' . print_r( $response, true ) . '</pre>';
		}

		/**
		 * Send the user to our support when his request is blocked by our firewall
		 */
		if ( $error = $this->blocked_by_firewall( $response ) ) {
			return $error;
		}

		if ( is_wp_error( $response ) ) {
			$body = wp_remote_retrieve_body( $response );
			if ( $body ) {
				return $body;
			} else {
				$curl = curl_version();

				return __( 'License couldn’t be activated. Please try again later.', 'advanced-ads' ) . " (cURL {$curl['version']})";
			}
		}

		$license_data = json_decode( wp_remote_retrieve_body( $response ) );
		// save license status.
		if ( ! empty( $license_data->license ) ) {
			update_option( $options_slug . '-license-status', $license_data->license, false );
		}
		if ( ! empty( $license_data->expires ) ) {
			update_option( $options_slug . '-license-expires', $license_data->expires, false );
		}

		// display activation problem.
		if ( ! empty( $license_data->error ) ) {
			// user friendly texts for errors.
			$errors = array(
				'license_not_activable' => __( 'This is the bundle license key.', 'advanced-ads' ),
				'item_name_mismatch'    => __( 'This is not the correct key for this add-on.', 'advanced-ads' ),
				'no_activations_left'   => __( 'There are no activations left.', 'advanced-ads' )
				                           . '&nbsp;'
				                           . sprintf( // translators: %1$s is a starting link tag, %2$s is the closing one.
					                           __( 'You can manage activations in %1$syour account%2$s.', 'advanced-ads' ),
					                           '<a href="' . ADVADS_URL . 'account/" target="_blank">',
					                           '</a>'
				                           ),
			);
			$error  = isset( $errors[ $license_data->error ] ) ? $errors[ $license_data->error ] : $license_data->error;
			if ( 'expired' === $license_data->error ) {
				return 'ex';
			} else {
				if ( isset( $errors[ $license_data->error ] ) ) {
					return $error;
				} else {
					return sprintf(
					// translators: %s is a string containing information about the issue.
						__( 'License is invalid. Reason: %s', 'advanced-ads' ),
						$error
					);
				}
			}
		} else {
			// reset license_expires admin notification.
			Advanced_Ads_Admin_Notices::get_instance()->remove_from_queue( 'license_expires' ); // this one is no longer added, but we keep the check here in case it is still in the queue for some users.
			Advanced_Ads_Admin_Notices::get_instance()->remove_from_queue( 'license_expired' ); // this one is no longer added, but we keep the check here in case it is still in the queue for some users.
			Advanced_Ads_Admin_Notices::get_instance()->remove_from_queue( 'license_invalid' );
			// save license key.
			$licenses           = $this->get_licenses();
			$licenses[ $addon ] = $license_key;
			$this->save_licenses( $licenses );
		}

		return 1;
	}

	/**
	 * Check if a request was blocked by our firewall
	 */
	public function blocked_by_firewall( $response ) {
		$response_code = wp_remote_retrieve_response_code( $response );
		if ( '403' == $response_code ) {
			$blocked_information = '–';
			if ( isset( $response['body'] ) ) {
				// look for the IP address in this line: `<td><span>95.90.238.103</span></td>`.
				$pattern = '/<span>([.0-9]*)<\/span>/';
				$matches = array();
				preg_match( $pattern, $response['body'], $matches );
				$ip                  = isset( $matches[1] ) ? $matches[1] : '–';
				$blocked_information = 'IP: ' . $ip;
			}

			// translators: %s is a list of server information like IP address. Just keep it as is.
			return sprintf( __( 'Your request was blocked by our firewall. Please send us the following information to unblock you: %s.', 'advanced-ads' ), $blocked_information );
		}

		return false;
	}

	/**
	 * Check if a specific license key was already activated for the current page
	 *
	 * @param string $license_key license key.
	 * @param string $plugin_name name of the add-on.
	 * @param string $options_slug slug of the option in the database.
	 *
	 * @return bool true if already activated
	 * @since 1.6.17
	 * @deprecated since version 1.7.2 because it only checks if a key is valid, not if the url registered with that key
	 */
	public function check_license( $license_key = '', $plugin_name = '', $options_slug = '' ) {

		if ( has_filter( 'advanced_ads_license_' . $options_slug ) ) {
			return apply_filters( 'advanced_ads_license_' . $options_slug, false, __METHOD__, $plugin_name, $options_slug, $license_key );
		}

		$api_params = array(
			'edd_action' => 'check_license',
			'license'    => $license_key,
			'item_name'  => urlencode( $plugin_name ),
		);
		$response   = wp_remote_get( add_query_arg( $api_params, ADVADS_URL ), array( 'timeout' => 15, 'sslverify' => false ) );
		if ( is_wp_error( $response ) ) {
			return false;
		}
		$license_data = json_decode( wp_remote_retrieve_body( $response ) );

		// if this license is still valid.
		if ( 'valid' === $license_data->license ) {
			update_option( $options_slug . '-license-expires', $license_data->expires, false );
			update_option( $options_slug . '-license-status', $license_data->license, false );

			return true;
		}

		return false;
	}

	/**
	 * Deactivate license key
	 *
	 * @param string $addon string with add-on identifier.
	 * @param string $plugin_name name of the add-on.
	 * @param string $options_slug slug of the option in the database.
	 *
	 * @return string
	 * @since 1.6.11
	 */
	public function deactivate_license( $addon = '', $plugin_name = '', $options_slug = '' ) {

		if ( '' === $addon || '' === $plugin_name || '' === $options_slug ) {
			return __( 'Error while trying to disable the license. Please contact support.', 'advanced-ads' );
		}

		$licenses    = $this->get_licenses();
		$license_key = isset( $licenses[ $addon ] ) ? $licenses[ $addon ] : '';

		if ( has_filter( 'advanced_ads_license_' . $options_slug ) ) {
			return apply_filters( 'advanced_ads_license_' . $options_slug, false, __METHOD__, $plugin_name, $options_slug, $license_key );
		}

		$api_params = array(
			'edd_action' => 'deactivate_license',
			'license'    => $license_key,
			'item_name'  => urlencode( $plugin_name ),
		);
		// send the remote request.
		$response = wp_remote_post(
			ADVADS_URL,
			array(
				'body'      => $api_params,
				'timeout'   => 15,
				'sslverify' => false,
			)
		);

		// show license debug output if constant is set.
		if ( defined( 'ADVANCED_ADS_SHOW_LICENSE_RESPONSE' ) ) {
			return '<pre>' . print_r( $response, true ) . '</pre>';
		}

		if ( is_wp_error( $response ) ) {
			$body = wp_remote_retrieve_body( $response );
			if ( $body ) {
				return $body;
			} else {
				return __( 'License couldn’t be deactivated. Please try again later.', 'advanced-ads' );
			}
		}

		$license_data = json_decode( wp_remote_retrieve_body( $response ) );

		/**
		 * Send the user to our support when his request is blocked by our firewall
		 */
		if ( $error = $this->blocked_by_firewall( $response ) ) {
			return $error;
		}

		// remove data.
		if ( 'deactivated' === $license_data->license ) {
			delete_option( $options_slug . '-license-status' );
			delete_option( $options_slug . '-license-expires' );
		} elseif ( 'failed' === $license_data->license ) {
			update_option( $options_slug . '-license-expires', $license_data->expires, false );
			update_option( $options_slug . '-license-status', $license_data->license, false );

			return 'ex';
		} else {
			return __( 'License couldn’t be deactivated. Please try again later.', 'advanced-ads' );
		}

		return 1;
	}

	/**
	 * Get license keys for all add-ons
	 *
	 * @return string[]
	 * @since 1.6.15
	 */
	public function get_licenses() {

		$licenses = array();

		if ( is_multisite() ) {
			// if multisite, get option from main blog.
			global $current_site;
			$licenses = get_blog_option( $current_site->blog_id, ADVADS_SLUG . '-licenses', array() );

		} else {
			$licenses = get_option( ADVADS_SLUG . '-licenses', array() );
		}

		return $licenses;
	}

	/**
	 * Save license keys for all add-ons
	 *
	 * @param array $licenses licenses.
	 *
	 * @since 1.7.2
	 */
	public function save_licenses( $licenses = array() ) {

		if ( is_multisite() ) {
			// if multisite, get option from main blog.
			global $current_site;
			update_blog_option( $current_site->blog_id, ADVADS_SLUG . '-licenses', $licenses );
		} else {
			update_option( ADVADS_SLUG . '-licenses', $licenses );
		}
	}

	/**
	 * Get license status of an add-on
	 *
	 * @param string $slug slug of the add-on.
	 *
	 * @return string $status license status, e.g. "valid" or "invalid"
	 * @since 1.6.15
	 */
	public function get_license_status( $slug = '' ) {

		$status = false;

		if ( is_multisite() ) {
			// if multisite, get option from main blog.
			global $current_site;
			$status = get_blog_option( $current_site->blog_id, $slug . '-license-status', false );
		} else {
			$status = get_option( $slug . '-license-status', false );
		}

		return $status;
	}

	/**
	 * If two or more add-ons use the same valid license this is probably an all-access customer
	 *
	 * @return bool
	 */
	public function get_probably_all_access() {
		$valid = array_filter( $this->get_licenses(), function ( $key ) {
			return $this->get_license_status( ADVADS_SLUG . '-' . $key );
		}, ARRAY_FILTER_USE_KEY );


		return array() !== $valid && max( array_count_values( $valid ) ) > 1;
	}

	/**
	 * Get license expired value of an add-on
	 *
	 * @param string $slug slug of the add-on.
	 *
	 * @return string $date expiry date of an add-on
	 * @since 1.6.15
	 */
	public function get_license_expires( $slug = '' ) {

		$date = false;

		if ( is_multisite() ) {
			// if multisite, get option from main blog.
			global $current_site;
			$date = get_blog_option( $current_site->blog_id, $slug . '-license-expires', false );
		} else {
			$date = get_option( $slug . '-license-expires', false );
		}

		return $date;
	}


	/**
	 * Add-on updater
	 *
	 * @since 1.5.7
	 */
	public function add_on_updater() {

		// ignore, if not main blog.
		if ( ( is_multisite() && ! is_main_site() ) ) {
			return;
		}

		/**
		 * List of registered add ons
		 * contains:
		 *        name
		 *        version
		 *        path
		 *        options_slug
		 *        short option slug (=key)
		 */
		$add_ons = apply_filters( 'advanced-ads-add-ons', array() );

		if ( array() === $add_ons ) {
			return;
		}

		// load license keys.
		$licenses = get_option( ADVADS_SLUG . '-licenses', array() );

		foreach ( $add_ons as $_add_on_key => $_add_on ) {

			// check if a license expired over time.
			$expiry_date = $this->get_license_expires( $_add_on['options_slug'] );
			$now         = time();
			if ( $expiry_date && 'lifetime' !== $expiry_date && strtotime( $expiry_date ) < $now ) {
				// remove license status.
				delete_option( $_add_on['options_slug'] . '-license-status' );
				continue;
			}

			// check status.
			if ( $this->get_license_status( $_add_on['options_slug'] ) !== 'valid' ) {
				continue;
			}

			// retrieve our license key.
			$license_key = isset( $licenses[ $_add_on_key ] ) ? $licenses[ $_add_on_key ] : '';

			// setup the updater.
			if ( $license_key ) {

				// register filter to set EDD transient to 86,400 seconds (day) instead of 3,600 (hours).
				$slug          = basename( $_add_on['path'], '.php' );
				$transient_key = md5( serialize( $slug . $license_key ) );

				add_filter( 'pre_update_option_' . $transient_key, array( $this, 'set_expiration_of_update_option' ) );

				new ADVADS_SL_Plugin_Updater(
					ADVADS_URL,
					$_add_on['path'],
					array(
						'version'   => $_add_on['version'],
						'license'   => $license_key,
						'item_name' => $_add_on['name'],
						'author'    => 'Thomas Maier',
					)
				);
			}
		}
	}

	/**
	 * Set the expiration of the updater transient key to 1 day instead of 1 hour to prevent too many update checks
	 *
	 * @deprecated since version 1.7.14 – not using transient anymore, but option
	 */
	public function set_expiration_of_update_transient( $expiration ) {

		return 86400;
	}

	/**
	 * Set the expiration of the updater transient key to 1 day instead of 1 hour to prevent too many update checks
	 *
	 * @return integer
	 * @since   1.7.14
	 */
	public function set_expiration_of_update_option( $value ) {

		$value['timeout'] = time() + 86400;

		return $value;
	}

	/**
	 * Add custom messages to plugin updater
	 *
	 * @param string $reply
	 * @param string $package
	 * @param string $updater
	 *
	 * @return string
	 *
	 * @todo check if this is still working.
	 */
	public function addon_upgrade_filter( $reply, $package, $updater ) {

		if ( isset( $updater->skin->plugin ) ) {
			$plugin_file = $updater->skin->plugin;
		} elseif ( isset( $updater->skin->plugin_info['Name'] ) ) {
			$add_on      = $this->get_installed_add_on_by_name( $updater->skin->plugin_info['Name'] );
			$plugin_file = plugin_basename( $add_on['path'] );
		}

		if ( isset( $plugin_file ) && $plugin_file ) {
			// hides the download url, but makes debugging harder
			// $updater->strings['downloading_package'] = __( 'Downloading updated version...', 'advanced-ads' );
			//$updater->skin->feedback( 'downloading_package' );

			// if AJAX; show direct update link as first possible solution
			if ( defined( 'DOING_AJAX' ) ) {
				$update_link                         = wp_nonce_url( self_admin_url( 'update.php?action=upgrade-plugin&plugin=' ) . $plugin_file, 'upgrade-plugin_' . $plugin_file );
				$updater->strings['download_failed'] = sprintf( __( 'Download failed. <a href="%s">Click here to try another method</a>.', 'advanced-ads' ), $update_link );
			} else {
				$updater->strings['download_failed'] = sprintf( __( 'Download failed. <a href="%s" target="_blank">Click here to learn why</a>.', 'advanced-ads' ), ADVADS_URL . 'manual/download-failed-updating-add-ons/#utm_source=advanced-ads&utm_medium=link&utm_campaign=download-failed' );
			}

		}

		/*$res = $updater->fs_connect( array( WP_CONTENT_DIR ) );
		if ( ! $res ) {
			return new WP_Error( 'no_credentials', __( "Error! Can't connect to filesystem", 'advanced-ads' ) );
		}*/

		return $reply;
	}

	/**
	 * Search if a name is in the add-on array and return the add-on data of it
	 *
	 * @param string $name name of an add-on.
	 *
	 * @return  array    array with the add-on data
	 */
	private function get_installed_add_on_by_name( $name = '' ) {

		$add_ons = apply_filters( 'advanced-ads-add-ons', array() );

		if ( is_array( $add_ons ) ) {
			foreach ( $add_ons as $key => $_add_on ) {
				if ( $_add_on['name'] === $name ) {
					return $_add_on;
				}
			}
		}

		return null;
	}

	/**
	 * Check if any license is valid
	 * can be used to display information for any Pro user only, like link to direct support
	 */
	public static function any_license_valid() {
		$add_ons = apply_filters( 'advanced-ads-add-ons', array() );

		if ( array() === $add_ons ) {
			return false;
		}

		foreach ( $add_ons as $_add_on ) {
			$status = self::get_instance()->get_license_status( $_add_on['options_slug'] );

			// check expiry date.
			$expiry_date = self::get_instance()->get_license_expires( $_add_on['options_slug'] );

			if ( ( $expiry_date && strtotime( $expiry_date ) > time() )
			     || 'valid' === $status
			     || 'lifetime' === $expiry_date ) {

				return true;
			}
		}

		return false;
	}


}
