<?php

class SpecialNotifications extends SpecialPage {

	/**
	 * Number of notification records to display per page/load
	 */
	const DISPLAY_NUM = 20;

	public function __construct() {
		parent::__construct( 'Notifications' );
	}

	public function execute( $par ) {

		$this->setHeaders();

		$out = $this->getOutput();
		$out->setPageTitle( $this->msg( 'echo-specialpage' )->text() );

		$user = $this->getUser();
		if ( $user->isAnon() ) {
			// return to this title upon login
			$returnTo = array( 'returnto' => $this->getPageTitle()->getPrefixedDBkey() );
			// the html message for anon users
			$anonMsgHtml = $this->msg(
				'echo-anon',
				SpecialPage::getTitleFor( 'Userlogin', 'signup' )->getFullURL( $returnTo ),
				SpecialPage::getTitleFor( 'Userlogin' )->getFullURL( $returnTo )
			)->parse();
			$out->addHTML( Html::rawElement( 'span', array( 'class' => 'plainlinks' ), $anonMsgHtml ) );
			return;
		}

		$out->addSubtitle( $this->buildSubtitle() );

		// The continue parameter to pull current set of data from, this
		// would be used for browsers with javascript disabled
		$continue = $this->getRequest()->getVal( 'continue', null );

		// Pull the notifications
		$notif = array();
		$notificationMapper = new EchoNotificationMapper();

		$attributeManager = EchoAttributeManager::newFromGlobalVars();
		$notifications = $notificationMapper->fetchByUser(
			$user,
			/* $limit = */self::DISPLAY_NUM + 1,
			$continue,
			$attributeManager->getUserEnabledEvents( $user, 'web' )
		);
		foreach ( $notifications as $notification ) {
			$notif[] = EchoDataOutputFormatter::formatOutput( $notification, 'html', $user );
		}

		// If there are no notifications, display a message saying so
		if ( !$notif ) {
			$out->addWikiMsg( 'echo-none' );
			return;
		}

		// Check if there is more data to load for next request
		if ( count( $notif ) > self::DISPLAY_NUM ) {
			$lastItem = array_pop( $notif );
			$nextContinue = $lastItem['timestamp']['utcunix'] . '|' . $lastItem['id'];
		} else {
			$nextContinue = null;
		}

		// Add the notifications to the page (interspersed with date headers)
		$dateHeader = '';
		$notices = '';
		$unread = array();
		$echoSeenTime = EchoSeenTime::newFromUser( $user );
		$seenTime = $echoSeenTime->getTime();
		foreach ( $notif as $row ) {
			$class = 'mw-echo-notification';

			if ( !isset( $row['read'] ) ) {
				$class .= ' mw-echo-unread';
				if ( !$row['targetpages'] ) {
					$unread[] = $row['id'];
				}
			}

			if ( $seenTime !== null && $row['timestamp']['mw'] > $seenTime ) {
				$class .= ' mw-echo-unseen';
			}

			if ( !$row['*'] ) {
				continue;
			}
			// Output the date header if it has not been displayed
			if ( $dateHeader !== $row['timestamp']['date'] ) {
				$dateHeader = $row['timestamp']['date'];
				$notices .= Html::rawElement( 'li', array( 'class' => 'mw-echo-date-section' ), $dateHeader );
			}

			$notices .= Html::rawElement(
				'li',
				array(
					'class' => $class,
					'data-notification-category' => $row['category'],
					'data-notification-event' => $row['id'],
					'data-notification-type' => $row['type']
				),
				$row['*']
			);
		}
		$html = Html::rawElement( 'ul', array( 'id' => 'mw-echo-special-container' ), $notices );

		// Build the more link
		if ( $nextContinue ) {
			$html .= Html::element(
				'a',
				array(
					'href' => SpecialPage::getTitleFor( 'Notifications' )->getLinkURL(
								array( 'continue' => $nextContinue )
							),
					'class' => 'mw-ui-button mw-ui-primary',
					'id' => 'mw-echo-more'
				),
				$this->msg( 'moredotdotdot' )->text()
			);
		}

		$out->addHTML( $html );
		$out->addModules( 'ext.echo.special' );
		$out->addJsConfigVars(
			array(
				'wgEchoDisplayNum' => self::DISPLAY_NUM,
				'wgEchoNextContinue' => $nextContinue,
				'wgEchoDateHeader' => $dateHeader
			)
		);
		// For no-js support
		$out->addModuleStyles( array( 'ext.echo.styles.notifications', 'ext.echo.styles.special' ) );

		DeferredUpdates::addCallableUpdate( function() use ( $user, $echoSeenTime, $unread ) {
			// Mark items as read
			if ( $unread ) {
				MWEchoNotifUser::newFromUser( $user )->markRead( $unread );
			}
			// Record time notifications have been seen
			$echoSeenTime->setTime( wfTimestamp( TS_MW ) );
		} );
	}

	/**
	 * Build the subtitle (more info and preference links)
	 * @return string HTML for the subtitle
	 */
	public function buildSubtitle() {
		global $wgEchoHelpPage;
		$lang = $this->getLanguage();
		$subtitleLinks = array();
		// More info link
		$subtitleLinks[] = Html::rawElement(
			'a',
			array(
				'href' => $wgEchoHelpPage,
				'id' => 'mw-echo-moreinfo-link',
				'class' => 'mw-echo-special-header-link',
				'title' => $this->msg( 'echo-more-info' )->text(),
				'target' => '_blank'
			),
			$this->msg( 'echo-more-info' )->text()
		);
		// Preferences link
		$subtitleLinks[] = Html::rawElement(
			'a',
			array(
				'href' => SpecialPage::getTitleFor( 'Preferences' )->getLinkURL() . '#mw-prefsection-echo',
				'id' => 'mw-echo-pref-link',
				'class' => 'mw-echo-special-header-link',
				'title' => $this->msg( 'preferences' )->text()
			),
			$this->msg( 'preferences' )->text()
		);
		return $lang->pipeList( $subtitleLinks );
	}

	protected function getGroupName() {
		return 'users';
	}
}