( function () {
	'use strict';

	var state = {
		group: null,
		language: null,
		messageList: null
	};

	mw.translate = mw.translate || {};

	mw.translate = $.extend( mw.translate, {

		/**
		 * Change the group that is currently displayed
		 * in the TUX translation editor.
		 *
		 * @param {Object} group a message group object.
		 */
		changeGroup: function ( group ) {
			var changes;

			if ( !checkDirty() ) {
				return;
			}

			state.group = group.id;

			changes = {
				group: group.id,
				showMessage: null

			};

			mw.translate.changeUrl( changes );
			mw.translate.updateTabLinks( changes );
			$( '.tux-editor-header .group-warning' ).empty();
			state.messageList.changeSettings( changes );
			updateGroupInformation( state );
		},

		changeLanguage: function ( language ) {
			var changes = {
				language: language,
				showMessage: null
			};

			state.language = language;

			mw.translate.changeUrl( changes );
			mw.translate.updateTabLinks( changes );
			$( '.tux-editor-header .group-warning' ).empty();
			state.messageList.changeSettings( changes );
			updateGroupInformation( state );

		},

		changeFilter: function ( filter ) {
			if ( !checkDirty() ) {
				return;
			}

			mw.translate.changeUrl( { filter: filter, showMessage: null } );
			state.messageList.changeSettings( { filter: getActualFilter( filter ) } );
		},

		changeUrl: function ( params, forceChange ) {
			var uri = new mw.Uri( window.location.href );

			uri.extend( params );

			// Support removing keys from the query
			$.each( params, function ( key, val ) {
				if ( val === null ) {
					delete uri.query[ key ];
				}
			} );

			if ( uri.toString() === window.location.href ) {
				return;
			}

			// If supported by the browser and requested, change the URL with
			// this URI but try not to leave the page.
			if ( !forceChange && history.pushState && $( '.tux-messagelist' ).length ) {
				history.pushState( uri, null, uri.toString() );
			} else {
				// For old browsers, just reload
				window.location.href = uri.toString();
			}
		},

		/**
		 * Updates the navigation tabs.
		 *
		 * @param {Object} params Url parameters to update.
		 * @since 2013.05
		 */
		updateTabLinks: function ( params ) {
			$( '.tux-tab a' ).each( function () {
				var $a, uri;

				$a = $( this );
				uri = new mw.Uri( $a.prop( 'href' ) );
				uri.extend( params );
				$a.prop( 'href', uri.toString() );
			} );
		}
	} );

	function getActualFilter( filter ) {
		var realFilters, uri;

		realFilters = [ '!ignored' ];
		uri = new mw.Uri( window.location.href );
		if ( uri.query.optional !== '1' ) {
			realFilters.push( '!optional' );
		}
		if ( filter ) {
			realFilters.push( filter );
		}

		return realFilters.join( '|' );
	}

	function checkDirty() {
		if ( mw.translate.isDirty() ) {
			// eslint-disable-next-line no-alert
			return confirm( mw.msg( 'translate-js-support-unsaved-warning' ) );
		}
		return true;
	}

	// Returns an array of jQuery objects of rows of translated
	// and proofread messages in the TUX editors.
	// Used several times.
	function getTranslatedMessages( $translateContainer ) {
		$translateContainer = $translateContainer || $( '.ext-translate-container' );
		return $translateContainer.find( '.tux-message-item' )
			.filter( '.translated, .proofread' );
	}

	/**
	 * Updates all group specific stuff on the page.
	 *
	 * @param {Object} state Information about current group and language.
	 * @param {string} state.group Message group id.
	 * @param {string} state.language Language.
	 */
	function updateGroupInformation( state ) {
		var props = 'id|priority|prioritylangs|priorityforce|description';

		mw.translate.recentGroups.append( state.group );

		mw.translate.getMessageGroup( state.group, props ).done( function ( group ) {
			updateDescription( group );
			updateGroupWarning( group, state.language );
		} );
	}

	function updateDescription( group ) {
		var
			api = new mw.Api(),
			$description = $( '.tux-editor-header .description' );

		if ( group.description === null ) {
			$description.empty();
			return;
		}

		api.parse( group.description ).done( function ( parsedDescription ) {
			// The parsed text is returned in a <p> tag,
			// so it's removed here.
			$description.html( parsedDescription );
		} ).fail( function () {
			$description.empty();
			mw.log( 'Error parsing description for group ' + group.id );
		} );
	}

	function updateGroupWarning( group, language ) {
		var preferredLanguages, headerMessage, languagesMessage,
			$groupWarning = $( '.tux-editor-header .group-warning' );

		if ( isPriorityLanguage( language, group.prioritylangs ) ) {
			return;
		}

		// Make a comma-separated list of preferred languages
		preferredLanguages = $.map( group.prioritylangs, function ( lang ) {
			// bidi isolation for language names
			return '<bdi>' + $.uls.data.getAutonym( lang ) + '</bdi>';
		} ).join( ', ' );

		headerMessage = mw.message(
			group.priorityforce ?
				'tpt-discouraged-language-force-header' :
				'tpt-discouraged-language-header',
			$.uls.data.getAutonym( language )
		).parse();

		languagesMessage = mw.message(
			group.priorityforce ?
				'tpt-discouraged-language-force-content' :
				'tpt-discouraged-language-content',
			preferredLanguages
		).parse();

		$groupWarning.append(
			$( '<p>' ).append( $( '<strong>' ).text( headerMessage ) ),
			// html because of the <bdi> and because it's parsed
			$( '<p>' ).html( languagesMessage )
		);
	}

	function isPriorityLanguage( language, priorityLanguages ) {
		// Don't show priority notice if the language is message documentation.
		if ( language === mw.config.get( 'wgTranslateDocumentationLanguageCode' ) ) {
			return true;
		}

		// If no priority language is set, return early.
		if ( !priorityLanguages ) {
			return true;
		}

		if ( priorityLanguages.indexOf( language ) !== -1 ) {
			return true;
		}

		return false;
	}

	function setupLanguageSelector( $element ) {
		var ulsOptions = {
			languages: mw.config.get( 'wgTranslateLanguages' ),
			showRegions: [ 'SP' ].concat( $.fn.lcd.defaults.showRegions ),
			onSelect: function ( language ) {
				mw.translate.changeLanguage( language );
				$element.text( $.uls.data.getAutonym( language ) );
			},
			ulsPurpose: 'translate-special-translate',
			quickList: function () {
				return mw.uls.getFrequentLanguageList();
			}
		};

		mw.translate.addExtraLanguagesToLanguageData( ulsOptions.languages, [ 'SP' ] );
		$element.uls( ulsOptions );
	}

	$( function () {
		var $translateContainer, $hideTranslatedButton, $messageList,
			filter, uri, position, offset, limit;

		$messageList = $( '.tux-messagelist' );
		state.group = $( '.tux-messagetable-loader' ).data( 'messagegroup' );
		state.language = $messageList.data( 'targetlangcode' );

		if ( $messageList.length ) {
			$messageList.messagetable();
			state.messageList = $messageList.data( 'messagetable' );

			uri = new mw.Uri( window.location.href );
			filter = uri.query.filter;
			offset = uri.query.showMessage;
			if ( offset ) {
				limit = uri.query.limit || 1;
				// Default to no filters
				filter = filter || '';
			}

			if ( filter === undefined ) {
				filter = '!translated';
			}

			$( '.tux-message-selector li' ).each( function () {
				var $this = $( this );

				if ( $this.data( 'filter' ) === filter ) {
					$this.addClass( 'selected' );
				}
			} );

			mw.translate.changeUrl( {
				group: state.group,
				language: state.language,
				filter: filter,
				showMessage: offset,
				optional: offset ? 1 : undefined
			} );

			// Start loading messages
			state.messageList.changeSettings( {
				group: state.group,
				language: state.language,
				offset: offset,
				limit: limit,
				filter: getActualFilter( filter )
			} );
		}

		if ( $( 'body' ).hasClass( 'rtl' ) ) {
			position = {
				my: 'right top',
				at: 'right+80 bottom+5'
			};
		}
		$( '.tux-breadcrumb__item--aggregate' ).msggroupselector( {
			onSelect: mw.translate.changeGroup,
			language: state.language,
			position: position,
			recent: mw.translate.recentGroups.get()
		} );

		updateGroupInformation( state );

		$( '.ext-translate-language-selector .uls' ).one( 'click', function () {
			var $target = $( this );
			mw.loader.using( 'ext.uls.mediawiki' ).done( function () {
				setupLanguageSelector( $target );
				$target.click();
			} );
		} );

		if ( $.fn.translateeditor ) {
			// New translation editor
			$( '.tux-message' ).translateeditor();
		}

		$translateContainer = $( '.ext-translate-container' );

		if ( mw.translate.canProofread() ) {
			$translateContainer.find( '.proofread-mode-button' ).removeClass( 'hide' );
		}

		$hideTranslatedButton = $translateContainer.find( '.tux-editor-clear-translated' );
		$hideTranslatedButton
			.prop( 'disabled', !getTranslatedMessages( $translateContainer ).length )
			.click( function () {
				getTranslatedMessages( $translateContainer ).remove();
				$( this ).prop( 'disabled', true );
			} );

		// Message filter click handler
		$translateContainer.find( '.row.tux-message-selector > li' ).on( 'click', function () {
			var newFilter,
				$this = $( this );

			if ( $this.hasClass( 'more' ) ) {
				return false;
			}

			newFilter = $this.data( 'filter' );

			// Remove the 'selected' class from all the items.
			// Some of them could have been moved to under the "more" menu,
			// so everything under .row.tux-message-selector is searched.
			$translateContainer.find( '.row.tux-message-selector .selected' )
				.removeClass( 'selected' );
			mw.translate.changeFilter( newFilter );
			$this.addClass( 'selected' );

			// TODO: this could should be in messagetable
			if ( newFilter === '!translated' ) {
				$hideTranslatedButton
					.removeClass( 'hide' )
					.prop( 'disabled', !getTranslatedMessages( $translateContainer ).length );
			} else {
				$hideTranslatedButton.addClass( 'hide' );
			}

			return false;
		} );

		// TODO: this could should be in messagetable
		if ( $( '.tux-messagetable-loader' ).data( 'filter' ) === '!translated' ) {
			$hideTranslatedButton.removeClass( 'hide' );
		} else {
			$hideTranslatedButton.addClass( 'hide' );
		}

		// Don't let clicking the items in the "more" menu
		// affect the rest of it.
		$( '.row.tux-message-selector .more ul' )
			.on( 'click', function ( e ) {
				e.stopPropagation();
			} );

		$( '#tux-option-optional' ).on( 'change', function () {
			var uri = new mw.Uri( window.location.href ),
				checked = $( this ).prop( 'checked' );

			mw.translate.changeUrl( { optional: checked ? 1 : 0 } );
			mw.translate.changeFilter( uri.query.filter );
		} );
	} );

}() );