<?php

// uncomment this line for testing
//set_site_transient( 'update_plugins', null );

/**
 * Allows plugins to use their own update API.
 *
 * @author Pippin Williamson
 * @version 1.6
 */
class SWP_Xpdf_Updater {
	private $api_url   = '';
	private $api_data  = array();
	private $name      = '';
	private $slug      = '';

	/**
	 * Class constructor.
	 *
	 * @uses plugin_basename()
	 * @uses hook()
	 *
	 * @param string  $_api_url     The URL pointing to the custom API endpoint.
	 * @param string  $_plugin_file Path to the plugin file.
	 * @param array   $_api_data    Optional data to send with API calls.
	 * @return void
	 */
	function __construct( $_api_url, $_plugin_file, $_api_data = null ) {
		$this->api_url  = trailingslashit( $_api_url );
		$this->api_data = $_api_data;
		$this->name     = plugin_basename( $_plugin_file );
		$this->slug     = basename( $_plugin_file, '.php' );
		$this->version  = $_api_data['version'];

		// Set up hooks.
		$this->init();
		add_action( 'admin_init', array( $this, 'show_changelog' ) );
	}

	/**
	 * Set up WordPress filters to hook into WP's update process.
	 *
	 * @uses add_filter()
	 *
	 * @return void
	 */
	public function init() {

		add_filter( 'pre_set_site_transient_update_plugins', array( $this, 'check_update' ) );
		add_filter( 'plugins_api', array( $this, 'plugins_api_filter' ), 10, 3 );

		add_action( 'after_plugin_row_' . $this->name, array( $this, 'show_update_notification' ), 10, 2 );
	}

	/**
	 * Check for Updates at the defined API endpoint and modify the update array.
	 *
	 * This function dives into the update API just when WordPress creates its update array,
	 * then adds a custom API call and injects the custom plugin data retrieved from the API.
	 * It is reassembled from parts of the native WordPress plugin update code.
	 * See wp-includes/update.php line 121 for the original wp_update_plugins() function.
	 *
	 * @uses api_request()
	 *
	 * @param array   $_transient_data Update array build by WordPress.
	 * @return array Modified update array with custom plugin data.
	 */
	function check_update( $_transient_data ) {

		global $pagenow;

		if( ! is_object( $_transient_data ) ) {
			$_transient_data = new stdClass;
		}

		if( 'plugins.php' == $pagenow && is_multisite() ) {
			return $_transient_data;
		}

		if ( empty( $_transient_data->response ) || empty( $_transient_data->response[ $this->name ] ) ) {

			$version_info = $this->api_request( 'plugin_latest_version', array( 'slug' => $this->slug ) );

			if ( false !== $version_info && is_object( $version_info ) && isset( $version_info->new_version ) ) {

				$this->did_check = true;

				if( version_compare( $this->version, $version_info->new_version, '<' ) ) {

					$_transient_data->response[ $this->name ] = $version_info;

				}

				$_transient_data->last_checked = time();
				$_transient_data->checked[ $this->name ] = $this->version;

			}

		}

		return $_transient_data;
	}

	/**
	 * show update nofication row -- needed for multisite subsites, because WP won't tell you otherwise!
	 *
	 * @param string  $file
	 * @param array   $plugin
	 */
	public function show_update_notification( $file, $plugin ) {

		if( ! current_user_can( 'update_plugins' ) ) {
			return;
		}

		if( ! is_multisite() ) {
			return;
		}

		if ( $this->name != $file ) {
			return;
		}

		// Remove our filter on the site transient
		remove_filter( 'pre_set_site_transient_update_plugins', array( $this, 'check_update' ), 10 );

		$update_cache = get_site_transient( 'update_plugins' );

		if ( ! is_object( $update_cache ) || empty( $update_cache->response ) || empty( $update_cache->response[ $this->name ] ) ) {

			$cache_key    = md5( 'edd_plugin_' .sanitize_key( $this->name ) . '_version_info' );
			$version_info = get_transient( $cache_key );

			if( false === $version_info ) {

				$version_info = $this->api_request( 'plugin_latest_version', array( 'slug' => $this->slug ) );

				set_transient( $cache_key, $version_info, 3600 );
			}


			if( ! is_object( $version_info ) ) {
				return;
			}

			if( version_compare( $this->version, $version_info->new_version, '<' ) ) {

				$update_cache->response[ $this->name ] = $version_info;

			}

			$update_cache->last_checked = time();
			$update_cache->checked[ $this->name ] = $this->version;

			set_site_transient( 'update_plugins', $update_cache );

		} else {

			$version_info = $update_cache->response[ $this->name ];

		}

		// Restore our filter
		add_filter( 'pre_set_site_transient_update_plugins', array( $this, 'check_update' ) );

		if ( ! empty( $update_cache->response[ $this->name ] ) && version_compare( $this->version, $version_info->new_version, '<' ) ) {

			// build a plugin list row, with update notification
			$wp_list_table = _get_list_table( 'WP_Plugins_List_Table' );
			echo '<tr class="plugin-update-tr"><td colspan="' . $wp_list_table->get_column_count() . '" class="plugin-update colspanchange"><div class="update-message">';

			$changelog_link = self_admin_url( 'index.php?edd_sl_action=view_plugin_changelog&plugin=' . $this->name . '&slug=' . $this->slug . '&TB_iframe=true&width=772&height=911' );

			if ( empty( $version_info->download_link ) ) {
				printf(
					__( 'There is a new version of %1$s available. <a target="_blank" class="thickbox" href="%2$s">View version %3$s details</a>.', 'edd' ),
					esc_html( $version_info->name ),
					esc_url( $changelog_link ),
					esc_html( $version_info->new_version )
				);
			} else {
				printf(
					__( 'There is a new version of %1$s available. <a target="_blank" class="thickbox" href="%2$s">View version %3$s details</a> or <a href="%4$s">update now</a>.', 'edd' ),
					esc_html( $version_info->name ),
					esc_url( $changelog_link ),
					esc_html( $version_info->new_version ),
					esc_url( wp_nonce_url( self_admin_url( 'update.php?action=upgrade-plugin&plugin=' ) . $this->name, 'upgrade-plugin_' . $this->name ) )
				);
			}

			echo '</div></td></tr>';
		}
	}


	/**
	 * Updates information on the "View version x.x details" page with custom data.
	 *
	 * @uses api_request()
	 *
	 * @param mixed   $_data
	 * @param string  $_action
	 * @param object  $_args
	 * @return object $_data
	 */
	function plugins_api_filter( $_data, $_action = '', $_args = null ) {


		if ( $_action != 'plugin_information' ) {

			return $_data;

		}

		if ( ! isset( $_args->slug ) || ( $_args->slug != $this->slug ) ) {

			return $_data;

		}

		$to_send = array(
			'slug'   => $this->slug,
			'is_ssl' => is_ssl(),
			'fields' => array(
				'banners' => false, // These will be supported soon hopefully
				'reviews' => false
			)
		);

		$api_response = $this->api_request( 'plugin_information', $to_send );

		if ( false !== $api_response ) {
			$_data = $api_response;
		}

		return $_data;
	}


	/**
	 * Disable SSL verification in order to prevent download update failures
	 *
	 * @param array   $args
	 * @param string  $url
	 * @return object $array
	 */
	function http_request_args( $args, $url ) {
		// If it is an https request and we are performing a package download, disable ssl verification
		if ( strpos( $url, 'https://' ) !== false && strpos( $url, 'edd_action=package_download' ) ) {
			$args['sslverify'] = false;
		}
		return $args;
	}

	/**
	 * Calls the API and, if successfull, returns the object delivered by the API.
	 *
	 * @uses get_bloginfo()
	 * @uses wp_remote_post()
	 * @uses is_wp_error()
	 *
	 * @param string  $_action The requested action.
	 * @param array   $_data   Parameters for the API action.
	 * @return false||object
	 */
	private function api_request( $_action, $_data ) {

		global $wp_version;

		$data = array_merge( $this->api_data, $_data );

		if ( $data['slug'] != $this->slug )
			return;

		if ( empty( $data['license'] ) )
			return;

		if( $this->api_url == home_url() ) {
			return false; // Don't allow a plugin to ping itself
		}

		$api_params = array(
			'edd_action' => 'get_version',
			'license'    => $data['license'],
			'item_name'  => isset( $data['item_name'] ) ? $data['item_name'] : false,
			'item_id'    => isset( $data['item_id'] ) ? $data['item_id'] : false,
			'slug'       => $data['slug'],
			'author'     => $data['author'],
			'url'        => home_url()
		);

		$request = wp_remote_post( $this->api_url, array( 'timeout' => 15, 'sslverify' => false, 'body' => $api_params ) );

		if ( ! is_wp_error( $request ) ) {
			$request = json_decode( wp_remote_retrieve_body( $request ) );
		}

		if ( $request && isset( $request->sections ) ) {
			$request->sections = maybe_unserialize( $request->sections );
		} else {
			$request = false;
		}

		return $request;
	}

	public function show_changelog() {


		if( empty( $_REQUEST['edd_sl_action'] ) || 'view_plugin_changelog' != $_REQUEST['edd_sl_action'] ) {
			return;
		}

		if( empty( $_REQUEST['plugin'] ) ) {
			return;
		}

		if( empty( $_REQUEST['slug'] ) ) {
			return;
		}

		if( ! current_user_can( 'update_plugins' ) ) {
			wp_die( __( 'You do not have permission to install plugin updates', 'edd' ), __( 'Error', 'edd' ), array( 'response' => 403 ) );
		}

		$response = $this->api_request( 'plugin_latest_version', array( 'slug' => $_REQUEST['slug'] ) );

		if( $response && isset( $response->sections['changelog'] ) ) {
			echo '<div style="background:#fff;padding:10px;">' . $response->sections['changelog'] . '</div>';
		}


		exit;
	}

}