/**
 * Wrapper for the RC form with hide/show links
 * Must be constructed after the model is initialized.
 *
 * @class mw.rcfilters.ui.FormWrapperWidget
 * @extends OO.ui.Widget
 *
 * @constructor
 * @param {mw.rcfilters.dm.FiltersViewModel} filtersModel Changes list view model
 * @param {mw.rcfilters.dm.ChangesListViewModel} changeListModel Changes list view model
 * @param {mw.rcfilters.Controller} controller RCfilters controller
 * @param {jQuery} $formRoot Root element of the form to attach to
 * @param {Object} config Configuration object
 */
var FormWrapperWidget = function MwRcfiltersUiFormWrapperWidget( filtersModel, changeListModel, controller, $formRoot, config ) {
	config = config || {};

	// Parent
	FormWrapperWidget.parent.call( this, $.extend( {}, config, {
		$element: $formRoot
	} ) );

	this.changeListModel = changeListModel;
	this.filtersModel = filtersModel;
	this.controller = controller;
	this.$submitButton = this.$element.find( 'form input[type=submit]' );

	this.$element
		.on( 'click', 'a[data-params]', this.onLinkClick.bind( this ) );

	this.$element
		.on( 'submit', 'form', this.onFormSubmit.bind( this ) );

	// Events
	this.changeListModel.connect( this, {
		invalidate: 'onChangesModelInvalidate',
		update: 'onChangesModelUpdate'
	} );

	// Initialize
	this.cleanUpFieldset();
	this.$element
		.addClass( 'mw-rcfilters-ui-FormWrapperWidget' );
};

/* Initialization */

OO.inheritClass( FormWrapperWidget, OO.ui.Widget );

/**
 * Respond to link click
 *
 * @param {jQuery.Event} e Event
 * @return {boolean} false
 */
FormWrapperWidget.prototype.onLinkClick = function ( e ) {
	this.controller.updateChangesList( $( e.target ).data( 'params' ) );
	return false;
};

/**
 * Respond to form submit event
 *
 * @param {jQuery.Event} e Event
 * @return {boolean} false
 */
FormWrapperWidget.prototype.onFormSubmit = function ( e ) {
	var data = {};

	// Collect all data from the form
	$( e.target ).find( 'input, select' ).each( function () {
		if ( this.type === 'hidden' || this.type === 'submit' ) {
			return;
		}

		if ( this.type === 'checkbox' && !this.checked ) {
			// Use a fixed value for unchecked checkboxes.
			data[ this.name ] = '';
		} else {
			// Use the live value for select, checked checkboxes, or non-checkbox input.
			data[ this.name ] = $( this ).val();
		}
	} );

	this.controller.updateChangesList( data );
	return false;
};

/**
 * Respond to model invalidate
 */
FormWrapperWidget.prototype.onChangesModelInvalidate = function () {
	this.$submitButton.prop( 'disabled', true );
};

/**
 * Respond to model update, replace the show/hide links with the ones from the
 * server so they feature the correct state.
 *
 * @param {jQuery|string} $changesList Updated changes list
 * @param {jQuery} $fieldset Updated fieldset
 * @param {string} noResultsDetails Type of no result error
 * @param {boolean} isInitialDOM Whether $changesListContent is the existing (already attached) DOM
 */
FormWrapperWidget.prototype.onChangesModelUpdate = function ( $changesList, $fieldset, noResultsDetails, isInitialDOM ) {
	this.$submitButton.prop( 'disabled', false );

	// Replace the entire fieldset
	this.$element.empty().append( $fieldset.contents() );

	if ( !isInitialDOM ) {
		// Make sure enhanced RC re-initializes correctly
		mw.hook( 'wikipage.content' ).fire( this.$element );
	}

	this.cleanUpFieldset();
};

/**
 * Clean up the old-style show/hide that we have implemented in the filter list
 */
FormWrapperWidget.prototype.cleanUpFieldset = function () {
	this.$element.find( '.clshowhideoption[data-feature-in-structured-ui=1]' ).each( function () {
		// HACK: Remove the text node after the span.
		// If there isn't one, we're at the end, so remove the text node before the span.
		// This would be unnecessary if we added separators with CSS.
		if ( this.nextSibling && this.nextSibling.nodeType === Node.TEXT_NODE ) {
			this.parentNode.removeChild( this.nextSibling );
		} else if ( this.previousSibling && this.previousSibling.nodeType === Node.TEXT_NODE ) {
			this.parentNode.removeChild( this.previousSibling );
		}
		// Remove the span itself
		this.parentNode.removeChild( this );
	} );

	// Hide namespaces and tags
	this.$element.find( '.namespaceForm' ).detach();
	this.$element.find( '.mw-tagfilter-label' ).closest( 'tr' ).detach();

	// Hide Related Changes page name form
	this.$element.find( '.targetForm' ).detach();

	// misc: limit, days, watchlist info msg
	this.$element.find( '.rclinks, .cldays, .wlinfo' ).detach();

	if ( !this.$element.find( '.mw-recentchanges-table tr' ).length ) {
		this.$element.find( '.mw-recentchanges-table' ).detach();
		this.$element.find( 'hr' ).detach();
	}

	// Get rid of all <br>s, which are inside rcshowhide
	// If we still have content in rcshowhide, the <br>s are
	// gone. Instead, the CSS now has a rule to mark all <span>s
	// inside .rcshowhide with display:block; to simulate newlines
	// where they're actually needed.
	this.$element.find( 'br' ).detach();
	if ( !this.$element.find( '.rcshowhide' ).contents().length ) {
		this.$element.find( '.rcshowhide' ).detach();
	}

	if ( this.$element.find( '.cloption' ).text().trim() === '' ) {
		this.$element.find( '.cloption-submit' ).detach();
	}

	this.$element.find(
		'.rclistfrom, .rcnotefrom, .rcoptions-listfromreset'
	).detach();

	// Get rid of the legend
	this.$element.find( 'legend' ).detach();

	// Check if the element is essentially empty, and detach it if it is
	if ( !this.$element.text().trim().length ) {
		this.$element.detach();
	}
};

module.exports = FormWrapperWidget;
