/*
 * Thanks to Dmitry Baranovsky and his Raphael library for inspiration!
 */

/*
 * @class SVG
 *
 * Although SVG is not available on IE7 and IE8, these browsers support [VML](https://en.wikipedia.org/wiki/Vector_Markup_Language), and the SVG renderer will fall back to VML in this case.
 *
 * VML was deprecated in 2012, which means VML functionality exists only for backwards compatibility
 * with old versions of Internet Explorer.
 */

// @namespace Browser; @property vml: Boolean
// `true` if the browser supports [VML](https://en.wikipedia.org/wiki/Vector_Markup_Language).
L.Browser.vml = !L.Browser.svg && (function () {
	try {
		var div = document.createElement('div');
		div.innerHTML = '<v:shape adj="1"/>';

		var shape = div.firstChild;
		shape.style.behavior = 'url(#default#VML)';

		return shape && (typeof shape.adj === 'object');

	} catch (e) {
		return false;
	}
}());

// redefine some SVG methods to handle VML syntax which is similar but with some differences
L.SVG.include(!L.Browser.vml ? {} : {

	_initContainer: function () {
		this._container = L.DomUtil.create('div', 'leaflet-vml-container');
	},

	_update: function () {
		if (this._map._animatingZoom) { return; }
		L.Renderer.prototype._update.call(this);
		this.fire('update');
	},

	_initPath: function (layer) {
		var container = layer._container = L.SVG.create('shape');

		L.DomUtil.addClass(container, 'leaflet-vml-shape ' + (this.options.className || ''));

		container.coordsize = '1 1';

		layer._path = L.SVG.create('path');
		container.appendChild(layer._path);

		this._updateStyle(layer);
	},

	_addPath: function (layer) {
		var container = layer._container;
		this._container.appendChild(container);

		if (layer.options.interactive) {
			layer.addInteractiveTarget(container);
		}
	},

	_removePath: function (layer) {
		var container = layer._container;
		L.DomUtil.remove(container);
		layer.removeInteractiveTarget(container);
	},

	_updateStyle: function (layer) {
		var stroke = layer._stroke,
		    fill = layer._fill,
		    options = layer.options,
		    container = layer._container;

		container.stroked = !!options.stroke;
		container.filled = !!options.fill;

		if (options.stroke) {
			if (!stroke) {
				stroke = layer._stroke = L.SVG.create('stroke');
			}
			container.appendChild(stroke);
			stroke.weight = options.weight + 'px';
			stroke.color = options.color;
			stroke.opacity = options.opacity;

			if (options.dashArray) {
				stroke.dashStyle = L.Util.isArray(options.dashArray) ?
				    options.dashArray.join(' ') :
				    options.dashArray.replace(/( *, *)/g, ' ');
			} else {
				stroke.dashStyle = '';
			}
			stroke.endcap = options.lineCap.replace('butt', 'flat');
			stroke.joinstyle = options.lineJoin;

		} else if (stroke) {
			container.removeChild(stroke);
			layer._stroke = null;
		}

		if (options.fill) {
			if (!fill) {
				fill = layer._fill = L.SVG.create('fill');
			}
			container.appendChild(fill);
			fill.color = options.fillColor || options.color;
			fill.opacity = options.fillOpacity;

		} else if (fill) {
			container.removeChild(fill);
			layer._fill = null;
		}
	},

	_updateCircle: function (layer) {
		var p = layer._point.round(),
		    r = Math.round(layer._radius),
		    r2 = Math.round(layer._radiusY || r);

		this._setPath(layer, layer._empty() ? 'M0 0' :
				'AL ' + p.x + ',' + p.y + ' ' + r + ',' + r2 + ' 0,' + (65535 * 360));
	},

	_setPath: function (layer, path) {
		layer._path.v = path;
	},

	_bringToFront: function (layer) {
		L.DomUtil.toFront(layer._container);
	},

	_bringToBack: function (layer) {
		L.DomUtil.toBack(layer._container);
	}
});

if (L.Browser.vml) {
	L.SVG.create = (function () {
		try {
			document.namespaces.add('lvml', 'urn:schemas-microsoft-com:vml');
			return function (name) {
				return document.createElement('<lvml:' + name + ' class="lvml">');
			};
		} catch (e) {
			return function (name) {
				return document.createElement('<' + name + ' xmlns="urn:schemas-microsoft.com:vml" class="lvml">');
			};
		}
	})();
}
