/*global define*/
define([
        '../../Core/defined',
        '../../Core/defineProperties',
        '../../Core/destroyObject',
        '../../Core/DeveloperError',
        '../../ThirdParty/knockout',
        '../getElement',
        './SelectionIndicatorViewModel'
    ], function(
        defined,
        defineProperties,
        destroyObject,
        DeveloperError,
        knockout,
        getElement,
        SelectionIndicatorViewModel) {
    "use strict";

    /**
     * A widget for displaying an indicator on a selected object.
     *
     * @alias SelectionIndicator
     * @constructor
     *
     * @param {Element|String} container The DOM element or ID that will contain the widget.
     * @param {Scene} scene The Scene instance to use.
     *
     * @exception {DeveloperError} Element with id "container" does not exist in the document.
     */
    function SelectionIndicator(container, scene) {
        //>>includeStart('debug', pragmas.debug);
        if (!defined(container)) {
            throw new DeveloperError('container is required.');
        }
        //>>includeEnd('debug')

        container = getElement(container);

        this._container = container;

        var el = document.createElement('div');
        el.className = 'cesium-selection-wrapper';
        el.setAttribute('data-bind', '\
style: { "top" : _screenPositionY, "left" : _screenPositionX },\
css: { "cesium-selection-wrapper-visible" : isVisible }');
        container.appendChild(el);
        this._element = el;

        var svgNS = 'http://www.w3.org/2000/svg';
        var path = 'M -34 -34 L -34 -11.25 L -30 -15.25 L -30 -30 L -15.25 -30 L -11.25 -34 L -34 -34 z M 11.25 -34 L 15.25 -30 L 30 -30 L 30 -15.25 L 34 -11.25 L 34 -34 L 11.25 -34 z M -34 11.25 L -34 34 L -11.25 34 L -15.25 30 L -30 30 L -30 15.25 L -34 11.25 z M 34 11.25 L 30 15.25 L 30 30 L 15.25 30 L 11.25 34 L 34 34 L 34 11.25 z';

        var svg = document.createElementNS(svgNS, 'svg:svg');
        svg.setAttribute('width', 160);
        svg.setAttribute('height', 160);
        svg.setAttribute('viewBox', '0 0 160 160');

        var group = document.createElementNS(svgNS, 'g');
        group.setAttribute('transform', 'translate(80,80)');
        svg.appendChild(group);

        var pathElement = document.createElementNS(svgNS, 'path');
        pathElement.setAttribute('data-bind', 'attr: { transform: _transform }');
        pathElement.setAttribute('d', path);
        group.appendChild(pathElement);

        el.appendChild(svg);

        var viewModel = new SelectionIndicatorViewModel(scene, this._element, this._container);
        this._viewModel = viewModel;

        knockout.applyBindings(this._viewModel, this._element);
    }

    defineProperties(SelectionIndicator.prototype, {
        /**
         * Gets the parent container.
         * @memberof SelectionIndicator.prototype
         *
         * @type {Element}
         */
        container : {
            get : function() {
                return this._container;
            }
        },

        /**
         * Gets the view model.
         * @memberof SelectionIndicator.prototype
         *
         * @type {SelectionIndicatorViewModel}
         */
        viewModel : {
            get : function() {
                return this._viewModel;
            }
        }
    });

    /**
     * @returns {Boolean} true if the object has been destroyed, false otherwise.
     */
    SelectionIndicator.prototype.isDestroyed = function() {
        return false;
    };

    /**
     * Destroys the widget.  Should be called if permanently
     * removing the widget from layout.
     */
    SelectionIndicator.prototype.destroy = function() {
        var container = this._container;
        knockout.cleanNode(this._element);
        container.removeChild(this._element);
        return destroyObject(this);
    };

    return SelectionIndicator;
});
