/**
 * Progress bars visually display the status of an operation, such as a download,
 * and can be either determinate or indeterminate:
 *
 * - **determinate** process bars show the percent of an operation that is complete.
 *
 * - **indeterminate** process bars use a visual display of motion to indicate that an operation
 *   is taking place. Because the extent of an indeterminate operation is unknown, the bar does
 *   not use percentages.
 *
 * The value of the `progress` configuration determines whether the bar is determinate or indeterminate.
 *
 *     @example
 *     // Examples of determinate and indeterminate progress bars.
 *     var progressBar1 = new OO.ui.ProgressBarWidget( {
 *         progress: 33
 *     } );
 *     var progressBar2 = new OO.ui.ProgressBarWidget();
 *
 *     // Create a FieldsetLayout to layout progress bars
 *     var fieldset = new OO.ui.FieldsetLayout;
 *     fieldset.addItems( [
 *        new OO.ui.FieldLayout( progressBar1, {label: 'Determinate', align: 'top'}),
 *        new OO.ui.FieldLayout( progressBar2, {label: 'Indeterminate', align: 'top'})
 *     ] );
 *     $( 'body' ).append( fieldset.$element );
 *
 * @class
 * @extends OO.ui.Widget
 *
 * @constructor
 * @param {Object} [config] Configuration options
 * @cfg {number|boolean} [progress=false] The type of progress bar (determinate or indeterminate).
 *  To create a determinate progress bar, specify a number that reflects the initial percent complete.
 *  By default, the progress bar is indeterminate.
 */
OO.ui.ProgressBarWidget = function OoUiProgressBarWidget( config ) {
	// Configuration initialization
	config = config || {};

	// Parent constructor
	OO.ui.ProgressBarWidget.super.call( this, config );

	// Properties
	this.$bar = $( '<div>' );
	this.progress = null;

	// Initialization
	this.setProgress( config.progress !== undefined ? config.progress : false );
	this.$bar.addClass( 'oo-ui-progressBarWidget-bar' );
	this.$element
		.attr( {
			role: 'progressbar',
			'aria-valuemin': 0,
			'aria-valuemax': 100
		} )
		.addClass( 'oo-ui-progressBarWidget' )
		.append( this.$bar );
};

/* Setup */

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

/* Static Properties */

OO.ui.ProgressBarWidget.static.tagName = 'div';

/* Methods */

/**
 * Get the percent of the progress that has been completed. Indeterminate progresses will return `false`.
 *
 * @return {number|boolean} Progress percent
 */
OO.ui.ProgressBarWidget.prototype.getProgress = function () {
	return this.progress;
};

/**
 * Set the percent of the process completed or `false` for an indeterminate process.
 *
 * @param {number|boolean} progress Progress percent or `false` for indeterminate
 */
OO.ui.ProgressBarWidget.prototype.setProgress = function ( progress ) {
	this.progress = progress;

	if ( progress !== false ) {
		this.$bar.css( 'width', this.progress + '%' );
		this.$element.attr( 'aria-valuenow', this.progress );
	} else {
		this.$bar.css( 'width', '' );
		this.$element.removeAttr( 'aria-valuenow' );
	}
	this.$element.toggleClass( 'oo-ui-progressBarWidget-indeterminate', !progress );
};