Map.js

/*
 * L.Map is the central class of the API - it is used to create a map.
 */

L.Map = L.Evented.extend({

	options: {
		crs: L.CRS.EPSG3857,

		/*
		center: LatLng,
		zoom: Number,
		layers: Array,
		*/

		fadeAnimation: true,
		trackResize: true,
		markerZoomAnimation: true
	},

	initialize: function (id, options) { // (HTMLElement or String, Object)
		options = L.setOptions(this, options);

		this._initContainer(id);
		this._initLayout();

		// hack for https://github.com/Leaflet/Leaflet/issues/1980
		this._onResize = L.bind(this._onResize, this);

		this._initEvents();

		if (options.maxBounds) {
			this.setMaxBounds(options.maxBounds);
		}

		if (options.center && options.zoom !== undefined) {
			this.setView(L.latLng(options.center), options.zoom, {reset: true});
		}

		this._handlers = [];
		this._layers = {};
		this._zoomBoundLayers = {};

		this.callInitHooks();

		this._addLayers(this.options.layers);
	},


	// public methods that modify map state

	// replaced by animation-powered implementation in Map.PanAnimation.js
	setView: function (center, zoom) {
		zoom = zoom === undefined ? this.getZoom() : zoom;
		this._resetView(L.latLng(center), this._limitZoom(zoom));
		return this;
	},

	setZoom: function (zoom, options) {
		if (!this._loaded) {
			this._zoom = this._limitZoom(zoom);
			return this;
		}
		return this.setView(this.getCenter(), zoom, {zoom: options});
	},

	zoomIn: function (delta, options) {
		return this.setZoom(this._zoom + (delta || 1), options);
	},

	zoomOut: function (delta, options) {
		return this.setZoom(this._zoom - (delta || 1), options);
	},

	setZoomAround: function (latlng, zoom, options) {
		var scale = this.getZoomScale(zoom),
		    viewHalf = this.getSize().divideBy(2),
		    containerPoint = latlng instanceof L.Point ? latlng : this.latLngToContainerPoint(latlng),

		    centerOffset = containerPoint.subtract(viewHalf).multiplyBy(1 - 1 / scale),
		    newCenter = this.containerPointToLatLng(viewHalf.add(centerOffset));

		return this.setView(newCenter, zoom, {zoom: options});
	},

	fitBounds: function (bounds, options) {

		options = options || {};
		bounds = bounds.getBounds ? bounds.getBounds() : L.latLngBounds(bounds);

		var paddingTL = L.point(options.paddingTopLeft || options.padding || [0, 0]),
		    paddingBR = L.point(options.paddingBottomRight || options.padding || [0, 0]),

		    zoom = this.getBoundsZoom(bounds, false, paddingTL.add(paddingBR)),
		    paddingOffset = paddingBR.subtract(paddingTL).divideBy(2),

		    swPoint = this.project(bounds.getSouthWest(), zoom),
		    nePoint = this.project(bounds.getNorthEast(), zoom),
		    center = this.unproject(swPoint.add(nePoint).divideBy(2).add(paddingOffset), zoom);

		zoom = options && options.maxZoom ? Math.min(options.maxZoom, zoom) : zoom;

		return this.setView(center, zoom, options);
	},

	fitWorld: function (options) {
		return this.fitBounds([[-90, -180], [90, 180]], options);
	},

	panTo: function (center, options) { // (LatLng)
		return this.setView(center, this._zoom, {pan: options});
	},

	panBy: function (offset) { // (Point)
		// replaced with animated panBy in Map.PanAnimation.js
		this.fire('movestart');

		this._rawPanBy(L.point(offset));

		this.fire('move');
		return this.fire('moveend');
	},

	setMaxBounds: function (bounds) {
		bounds = L.latLngBounds(bounds);

		this.options.maxBounds = bounds;

		if (!bounds) {
			return this.off('moveend', this._panInsideMaxBounds);
		}

		if (this._loaded) {
			this._panInsideMaxBounds();
		}

		return this.on('moveend', this._panInsideMaxBounds);
	},

	panInsideBounds: function (bounds, options) {
		var center = this.getCenter(),
			newCenter = this._limitCenter(center, this._zoom, bounds);

		if (center.equals(newCenter)) { return this; }

		return this.panTo(newCenter, options);
	},

	invalidateSize: function (options) {
		if (!this._loaded) { return this; }

		options = L.extend({
			animate: false,
			pan: true
		}, options === true ? {animate: true} : options);

		var oldSize = this.getSize();
		this._sizeChanged = true;
		this._initialCenter = null;

		var newSize = this.getSize(),
		    oldCenter = oldSize.divideBy(2).round(),
		    newCenter = newSize.divideBy(2).round(),
		    offset = oldCenter.subtract(newCenter);

		if (!offset.x && !offset.y) { return this; }

		if (options.animate && options.pan) {
			this.panBy(offset);

		} else {
			if (options.pan) {
				this._rawPanBy(offset);
			}

			this.fire('move');

			if (options.debounceMoveend) {
				clearTimeout(this._sizeTimer);
				this._sizeTimer = setTimeout(L.bind(this.fire, this, 'moveend'), 200);
			} else {
				this.fire('moveend');
			}
		}

		return this.fire('resize', {
			oldSize: oldSize,
			newSize: newSize
		});
	},

	// TODO handler.addTo
	addHandler: function (name, HandlerClass) {
		if (!HandlerClass) { return this; }

		var handler = this[name] = new HandlerClass(this);

		this._handlers.push(handler);

		if (this.options[name]) {
			handler.enable();
		}

		return this;
	},

	remove: function () {
		if (this._loaded) {
			this.fire('unload');
		}

		this._initEvents('off');

		try {
			// throws error in IE6-8
			delete this._container._leaflet;
		} catch (e) {
			this._container._leaflet = undefined;
		}

		L.DomUtil.remove(this._mapPane);

		if (this._clearControlPos) {
			this._clearControlPos();
		}

		this._clearHandlers();

		return this;
	},

	createPane: function (name, container) {
		var className = 'leaflet-pane' + (name ? ' leaflet-' + name.replace('Pane', '') + '-pane' : ''),
		    pane = L.DomUtil.create('div', className, container || this._mapPane);

		if (name) {
			this._panes[name] = pane;
		}
		return pane;
	},


	// public methods for getting map state

	getCenter: function () { // (Boolean) -> LatLng
		this._checkIfLoaded();

		if (this._initialCenter && !this._moved()) {
			return this._initialCenter;
		}
		return this.layerPointToLatLng(this._getCenterLayerPoint());
	},

	getZoom: function () {
		return this._zoom;
	},

	getBounds: function () {
		var bounds = this.getPixelBounds(),
		    sw = this.unproject(bounds.getBottomLeft()),
		    ne = this.unproject(bounds.getTopRight());

		return new L.LatLngBounds(sw, ne);
	},

	getMinZoom: function () {
		return this.options.minZoom === undefined ? this._layersMinZoom || 0 : this.options.minZoom;
	},

	getMaxZoom: function () {
		return this.options.maxZoom === undefined ?
			(this._layersMaxZoom === undefined ? Infinity : this._layersMaxZoom) :
			this.options.maxZoom;
	},

	getBoundsZoom: function (bounds, inside, padding) { // (LatLngBounds[, Boolean, Point]) -> Number
		bounds = L.latLngBounds(bounds);

		var zoom = this.getMinZoom() - (inside ? 1 : 0),
		    maxZoom = this.getMaxZoom(),
		    size = this.getSize(),

		    nw = bounds.getNorthWest(),
		    se = bounds.getSouthEast(),

		    zoomNotFound = true,
		    boundsSize;

		padding = L.point(padding || [0, 0]);

		do {
			zoom++;
			boundsSize = this.project(se, zoom).subtract(this.project(nw, zoom)).add(padding);
			zoomNotFound = !inside ? size.contains(boundsSize) : boundsSize.x < size.x || boundsSize.y < size.y;

		} while (zoomNotFound && zoom <= maxZoom);

		if (zoomNotFound && inside) {
			return null;
		}

		return inside ? zoom : zoom - 1;
	},

	getSize: function () {
		if (!this._size || this._sizeChanged) {
			this._size = new L.Point(
				this._container.clientWidth,
				this._container.clientHeight);

			this._sizeChanged = false;
		}
		return this._size.clone();
	},

	getPixelBounds: function () {
		var topLeftPoint = this._getTopLeftPoint();
		return new L.Bounds(topLeftPoint, topLeftPoint.add(this.getSize()));
	},

	getPixelOrigin: function () {
		this._checkIfLoaded();
		return this._initialTopLeftPoint;
	},

	getPixelWorldBounds: function () {
		return this.options.crs.getProjectedBounds(this.getZoom());
	},

	getPane: function (pane) {
		return typeof pane === 'string' ? this._panes[pane] : pane;
	},

	getPanes: function () {
		return this._panes;
	},

	getContainer: function () {
		return this._container;
	},


	// TODO replace with universal implementation after refactoring projections

	getZoomScale: function (toZoom) {
		var crs = this.options.crs;
		return crs.scale(toZoom) / crs.scale(this._zoom);
	},

	getScaleZoom: function (scale) {
		return this._zoom + (Math.log(scale) / Math.LN2);
	},


	// conversion methods

	project: function (latlng, zoom) { // (LatLng[, Number]) -> Point
		zoom = zoom === undefined ? this._zoom : zoom;
		return this.options.crs.latLngToPoint(L.latLng(latlng), zoom);
	},

	unproject: function (point, zoom) { // (Point[, Number]) -> LatLng
		zoom = zoom === undefined ? this._zoom : zoom;
		return this.options.crs.pointToLatLng(L.point(point), zoom);
	},

	layerPointToLatLng: function (point) { // (Point)
		var projectedPoint = L.point(point).add(this.getPixelOrigin());
		return this.unproject(projectedPoint);
	},

	latLngToLayerPoint: function (latlng) { // (LatLng)
		var projectedPoint = this.project(L.latLng(latlng))._round();
		return projectedPoint._subtract(this.getPixelOrigin());
	},

	wrapLatLng: function (latlng) {
		return this.options.crs.wrapLatLng(L.latLng(latlng));
	},

	distance: function (latlng1, latlng2) {
		return this.options.crs.distance(L.latLng(latlng1), L.latLng(latlng2));
	},

	containerPointToLayerPoint: function (point) { // (Point)
		return L.point(point).subtract(this._getMapPanePos());
	},

	layerPointToContainerPoint: function (point) { // (Point)
		return L.point(point).add(this._getMapPanePos());
	},

	containerPointToLatLng: function (point) {
		var layerPoint = this.containerPointToLayerPoint(L.point(point));
		return this.layerPointToLatLng(layerPoint);
	},

	latLngToContainerPoint: function (latlng) {
		return this.layerPointToContainerPoint(this.latLngToLayerPoint(L.latLng(latlng)));
	},

	mouseEventToContainerPoint: function (e) { // (MouseEvent)
		return L.DomEvent.getMousePosition(e, this._container);
	},

	mouseEventToLayerPoint: function (e) { // (MouseEvent)
		return this.containerPointToLayerPoint(this.mouseEventToContainerPoint(e));
	},

	mouseEventToLatLng: function (e) { // (MouseEvent)
		return this.layerPointToLatLng(this.mouseEventToLayerPoint(e));
	},


	// map initialization methods

	_initContainer: function (id) {
		var container = this._container = L.DomUtil.get(id);

		if (!container) {
			throw new Error('Map container not found.');
		} else if (container._leaflet) {
			throw new Error('Map container is already initialized.');
		}

		container._leaflet = true;
	},

	_initLayout: function () {
		var container = this._container;

		this._fadeAnimated = this.options.fadeAnimation && L.Browser.any3d;

		L.DomUtil.addClass(container, 'leaflet-container' +
			(L.Browser.touch ? ' leaflet-touch' : '') +
			(L.Browser.retina ? ' leaflet-retina' : '') +
			(L.Browser.ielt9 ? ' leaflet-oldie' : '') +
			(L.Browser.safari ? ' leaflet-safari' : '') +
			(this._fadeAnimated ? ' leaflet-fade-anim' : ''));

		var position = L.DomUtil.getStyle(container, 'position');

		if (position !== 'absolute' && position !== 'relative' && position !== 'fixed') {
			container.style.position = 'relative';
		}

		this._initPanes();

		if (this._initControlPos) {
			this._initControlPos();
		}
	},

	_initPanes: function () {
		var panes = this._panes = {};

		this._mapPane = this.createPane('mapPane', this._container);

		this.createPane('tilePane');
		this.createPane('shadowPane');
		this.createPane('overlayPane');
		this.createPane('markerPane');
		this.createPane('popupPane');

		if (!this.options.markerZoomAnimation) {
			L.DomUtil.addClass(panes.markerPane, 'leaflet-zoom-hide');
			L.DomUtil.addClass(panes.shadowPane, 'leaflet-zoom-hide');
		}
	},


	// private methods that modify map state

	_resetView: function (center, zoom, preserveMapOffset, afterZoomAnim) {

		var zoomChanged = (this._zoom !== zoom);

		if (!afterZoomAnim) {
			this.fire('movestart');

			if (zoomChanged) {
				this.fire('zoomstart');
			}
		}

		this._zoom = zoom;
		this._initialCenter = center;

		this._initialTopLeftPoint = this._getNewTopLeftPoint(center);

		if (!preserveMapOffset) {
			L.DomUtil.setPosition(this._mapPane, new L.Point(0, 0));
		} else {
			this._initialTopLeftPoint._add(this._getMapPanePos());
		}

		var loading = !this._loaded;
		this._loaded = true;

		if (loading) {
			this.fire('load');
		}

		this.fire('viewreset', {hard: !preserveMapOffset});

		this.fire('move');

		if (zoomChanged || afterZoomAnim) {
			this.fire('zoomend');
		}

		this.fire('moveend', {hard: !preserveMapOffset});
	},

	_rawPanBy: function (offset) {
		L.DomUtil.setPosition(this._mapPane, this._getMapPanePos().subtract(offset));
	},

	_getZoomSpan: function () {
		return this.getMaxZoom() - this.getMinZoom();
	},

	_panInsideMaxBounds: function () {
		this.panInsideBounds(this.options.maxBounds);
	},

	_checkIfLoaded: function () {
		if (!this._loaded) {
			throw new Error('Set map center and zoom first.');
		}
	},

	// map events

	_initEvents: function (onOff) {
		if (!L.DomEvent) { return; }

		onOff = onOff || 'on';

		L.DomEvent[onOff](this._container,
			'click dblclick mousedown mouseup mouseenter mouseleave mousemove contextmenu',
			this._handleMouseEvent, this);

		if (this.options.trackResize) {
			L.DomEvent[onOff](window, 'resize', this._onResize, this);
		}
	},

	_onResize: function () {
		L.Util.cancelAnimFrame(this._resizeRequest);
		this._resizeRequest = L.Util.requestAnimFrame(
		        function () { this.invalidateSize({debounceMoveend: true}); }, this, false, this._container);
	},

	_handleMouseEvent: function (e) {
		if (!this._loaded) { return; }

		this._fireMouseEvent(this, e,
				e.type === 'mouseenter' ? 'mouseover' :
				e.type === 'mouseleave' ? 'mouseout' : e.type);
	},

	_fireMouseEvent: function (obj, e, type, propagate, latlng) {
		type = type || e.type;

		if (type === 'click') {
			if (!e._simulated && ((this.dragging && this.dragging.moved()) ||
			                      (this.boxZoom && this.boxZoom.moved()))) { return; }
			obj.fire('preclick');
		}

		if (!obj.listens(type, propagate) || L.DomEvent._skipped(e)) { return; }

		if (type === 'contextmenu') {
			L.DomEvent.preventDefault(e);
		}
		if (type === 'click' || type === 'dblclick' || type === 'contextmenu') {
			L.DomEvent.stopPropagation(e);
		}

		var data = {
			originalEvent: e,
			containerPoint: this.mouseEventToContainerPoint(e)
		};

		data.layerPoint = this.containerPointToLayerPoint(data.containerPoint);
		data.latlng = latlng || this.layerPointToLatLng(data.layerPoint);

		obj.fire(type, data, propagate);
	},

	_clearHandlers: function () {
		for (var i = 0, len = this._handlers.length; i < len; i++) {
			this._handlers[i].disable();
		}
	},

	whenReady: function (callback, context) {
		if (this._loaded) {
			callback.call(context || this, this);
		} else {
			this.on('load', callback, context);
		}
		return this;
	},


	// private methods for getting map state

	_getMapPanePos: function () {
		return L.DomUtil.getPosition(this._mapPane);
	},

	_moved: function () {
		var pos = this._getMapPanePos();
		return pos && !pos.equals([0, 0]);
	},

	_getTopLeftPoint: function () {
		return this.getPixelOrigin().subtract(this._getMapPanePos());
	},

	_getNewTopLeftPoint: function (center, zoom) {
		var viewHalf = this.getSize()._divideBy(2);
		// TODO round on display, not calculation to increase precision?
		return this.project(center, zoom)._subtract(viewHalf)._round();
	},

	_latLngToNewLayerPoint: function (latlng, newZoom, newCenter) {
		var topLeft = this._getNewTopLeftPoint(newCenter, newZoom).add(this._getMapPanePos());
		return this.project(latlng, newZoom)._subtract(topLeft);
	},

	// layer point of the current center
	_getCenterLayerPoint: function () {
		return this.containerPointToLayerPoint(this.getSize()._divideBy(2));
	},

	// offset of the specified place to the current center in pixels
	_getCenterOffset: function (latlng) {
		return this.latLngToLayerPoint(latlng).subtract(this._getCenterLayerPoint());
	},

	// adjust center for view to get inside bounds
	_limitCenter: function (center, zoom, bounds) {

		if (!bounds) { return center; }

		var centerPoint = this.project(center, zoom),
		    viewHalf = this.getSize().divideBy(2),
		    viewBounds = new L.Bounds(centerPoint.subtract(viewHalf), centerPoint.add(viewHalf)),
		    offset = this._getBoundsOffset(viewBounds, bounds, zoom);

		return this.unproject(centerPoint.add(offset), zoom);
	},

	// adjust offset for view to get inside bounds
	_limitOffset: function (offset, bounds) {
		if (!bounds) { return offset; }

		var viewBounds = this.getPixelBounds(),
		    newBounds = new L.Bounds(viewBounds.min.add(offset), viewBounds.max.add(offset));

		return offset.add(this._getBoundsOffset(newBounds, bounds));
	},

	// returns offset needed for pxBounds to get inside maxBounds at a specified zoom
	_getBoundsOffset: function (pxBounds, maxBounds, zoom) {
		var nwOffset = this.project(maxBounds.getNorthWest(), zoom).subtract(pxBounds.min),
		    seOffset = this.project(maxBounds.getSouthEast(), zoom).subtract(pxBounds.max),

		    dx = this._rebound(nwOffset.x, -seOffset.x),
		    dy = this._rebound(nwOffset.y, -seOffset.y);

		return new L.Point(dx, dy);
	},

	_rebound: function (left, right) {
		return left + right > 0 ?
			Math.round(left - right) / 2 :
			Math.max(0, Math.ceil(left)) - Math.max(0, Math.floor(right));
	},

	_limitZoom: function (zoom) {
		var min = this.getMinZoom(),
		    max = this.getMaxZoom();

		return Math.max(min, Math.min(max, zoom));
	}
});

L.map = function (id, options) {
	return new L.Map(id, options);
};