<?php
/**
 * DiscussionTools extension hooks
 *
 * @file
 * @ingroup Extensions
 * @license MIT
 */

class DiscussionToolsHooks {

	public static function onRegistration() {
		global $wgLocaltimezone;
		// If $wgLocaltimezone isn't hard-coded, it is evaluated from the system
		// timezone. On some systems this isn't guaranteed to be static, for example
		// on Debian, GMT can get converted to UTC, instead of Europe/London.
		//
		// Timestamp parsing assumes that the timezone never changes.
		//
		// HACK: Do not run this test on CI as $wgLocaltimezone is not configured.
		if ( !$wgLocaltimezone && !getenv( 'ZUUL_PROJECT' ) ) {
			throw new \ConfigException( 'DiscussionTools requires $wgLocaltimezone to be set' );
		}
	}

	/**
	 * Adds DiscussionTools JS to the output.
	 *
	 * This is attached to the MediaWiki 'BeforePageDisplay' hook.
	 *
	 * @param OutputPage $output The page view.
	 * @param Skin $skin The skin that's going to build the UI.
	 */
	public static function onBeforePageDisplay( OutputPage $output, Skin $skin ) {
		$title = $output->getTitle();
		$actionName = Action::getActionName( $output->getContext() );
		if (
			// Don't show on edit pages
			$actionName !== 'edit' &&
			$actionName !== 'submit' &&
			// Only wikitext pages (e.g. not Flow boards)
			$title->getContentModel() === CONTENT_MODEL_WIKITEXT &&
			$title->isTalkPage()
			// TODO: Allow non talk pages to be treated as talk pages
			// using a magic word.
		) {
			$output->addModules( [
				'ext.discussionTools.init'
			] );
		}
	}
}