/*!
 * VisualEditor AnnotationContextItem class.
 *
 * @copyright See AUTHORS.txt
 */

/**
 * Context item for an annotation.
 *
 * @class
 * @abstract
 * @extends ve.ui.LinearContextItem
 *
 * @param {ve.ui.LinearContext} context Context the item is in
 * @param {ve.dm.Model} model Model the item is related to
 * @param {Object} [config] Configuration options
 */
ve.ui.AnnotationContextItem = function VeUiAnnotationContextItem( context, model, config ) {
	// Parent constructor
	ve.ui.AnnotationContextItem.super.call( this, context, model, config );

	// Initialization
	this.$element.addClass( 've-ui-annotationContextItem' );

	if ( this.context.isMobile() ) {
		this.clearButton = new OO.ui.ButtonWidget( {
			framed: false,
			label: this.constructor.static.clearMsg,
			icon: this.constructor.static.clearIcon,
			flags: [ 'destructive' ]
		} );
		if ( this.isClearable() && !this.isReadOnly() ) {
			this.$foot.append( this.clearButton.$element );
		}
	} else {
		this.clearButton = new OO.ui.ButtonWidget( {
			title: this.constructor.static.clearMsg,
			icon: this.constructor.static.clearIcon,
			flags: [ 'destructive' ]
		} );
		if ( this.isClearable() && !this.isReadOnly() ) {
			this.actionButtons.addItems( [ this.clearButton ], 0 );
		}
	}
	this.clearButton.connect( this, { click: 'onClearButtonClick' } );
};

/* Inheritance */

OO.inheritClass( ve.ui.AnnotationContextItem, ve.ui.LinearContextItem );

/* Static Properties */

ve.ui.AnnotationContextItem.static.clearable = true;
ve.ui.AnnotationContextItem.static.clearIcon = 'cancel';
ve.ui.AnnotationContextItem.static.clearMsg = OO.ui.deferMsg( 'visualeditor-clearbutton-tooltip' );

/* Methods */

/**
 * Check if item is clearable.
 *
 * @return {boolean} Item is clearable
 */
ve.ui.AnnotationContextItem.prototype.isClearable = function () {
	return this.constructor.static.clearable;
};

/**
 * Handle clear button click events.
 *
 * @localdoc Removes any modelClasses annotations from the current fragment
 *
 * @protected
 */
ve.ui.AnnotationContextItem.prototype.onClearButtonClick = function () {
	ve.track( 'activity.' + this.constructor.static.name, { action: 'context-clear' } );
	this.applyToAnnotations( ( fragment, annotation ) => {
		fragment.annotateContent( 'clear', annotation );
	} );
};

/**
 * Apply a callback to every modelClass annotation in the current fragment
 *
 * @param  {Function} callback Callback, will be passed fragment and annotation
 */
ve.ui.AnnotationContextItem.prototype.applyToAnnotations = function ( callback ) {
	const modelClasses = this.constructor.static.modelClasses;

	let fragment = this.getFragment(),
		annotations = fragment.getAnnotations( true ).filter( ( annotation ) => ve.isInstanceOfAny( annotation, modelClasses ) ).get();
	if (
		!annotations.length &&
		fragment.getSelection().isCollapsed() &&
		fragment.getDocument().data.isContentOffset( fragment.getSelection().getRange().start )
	) {
		// Expand to nearest word and try again
		fragment = fragment.expandLinearSelection( 'word' );

		annotations = fragment.getAnnotations( true ).filter( ( annotation ) => ve.isInstanceOfAny( annotation, modelClasses ) ).get();
	}
	for ( let i = 0, len = annotations.length; i < len; i++ ) {
		callback( fragment.expandLinearSelection( 'annotation', annotations[ i ] ), annotations[ i ] );
	}
};

/**
 * Find the CE view for the annotation related to this context item
 *
 * Problem: Going from the model to the view is difficult, as there can be many views of any given model.
 * Assumption: an active annotation context item must mean the focus is within the relevant annotation.
 *
 * @return {ve.ce.Annotation|undefined} The annotation view, if it's found, or undefined if not
 */
ve.ui.AnnotationContextItem.prototype.getAnnotationView = function () {
	const model = this.model,
		surfaceView = this.context.getSurface().getView();

	function isThisModel( annotationView ) {
		return model === annotationView.model;
	}

	let annotations = [];
	// Use surfaceView.contexedAnnotations when available, i.e. when
	// the user clicked/tapped on the annotation.
	if ( surfaceView.contexedAnnotations ) {
		annotations = surfaceView.contexedAnnotations.filter( isThisModel );
	}
	if ( !annotations.length ) {
		annotations = surfaceView.annotationsAtModelSelection( isThisModel );
	}

	return annotations.length ? annotations[ 0 ] : undefined;
};