goog.provide('ol.Map');

goog.require('ol.Loc');
goog.require('ol.Bounds');
goog.require('ol.Projection');
goog.require('ol.control.Control');
goog.require('ol.renderer.MapRenderer');
goog.require('ol.handler.Drag');
goog.require('ol.handler.MouseWheel');
goog.require('ol.handler.Click');

goog.require('goog.dom');
goog.require('goog.math');
goog.require('goog.asserts');
goog.require('goog.events.EventTarget');

/**
 * @define {boolean} Whether to enable the drag handler.
 */
ol.ENABLE_DRAG_HANDLER = true;

/**
 * @define {boolean} Whether to enable the mousewheel handler.
 */
ol.ENABLE_MOUSEWHEEL_HANDLER = true;

/**
 * @define {boolean} Whether to enable the click handler.
 */
ol.ENABLE_CLICK_HANDLER = true;

/**
 * @export
 * @constructor
 * @extends {goog.events.EventTarget}
 *
 * @event layeradd Fires when a layer is added to the map. The event object
 *     contains a 'layer' property referencing the added layer.
 */
ol.Map = function() {

    goog.base(this);

    /**
     * @private
     * @type {ol.Projection}
     */
    this.projection_ = null;

    /**
     * @private
     * @type {ol.Projection}
     */
    this.userProjection_ = null;

    /**
     * @private
     * @type {ol.Loc}
     */
    this.center_ = null;

    /**
     * @private
     * @type {number|undefined}
     */
    this.zoom_ = undefined;

    /**
     * @private
     * @type {number}
     */
    this.numZoomLevels_ = 22;

    /**
     * @private
     * @type {Array}
     */
    this.resolutions_ = null;

    /**
     * @private
     * @type {Array}
     */
    this.layers_ = null;

    /**
     * @private
     * @type {Array}
     */
    this.controls_ = null;

    /**
     * @private
     * @type {ol.Bounds}
     */
    this.maxExtent_ = null;

    /**
     * @private
     * @type {number|undefined}
     */
    this.maxResolution_ = undefined;
    
    /**
     * @private
     * @type {Element}
     */
    this.viewport_ = null;

    /**
     * @private
     * @type {goog.math.Size}
     */
    this.viewportSize_ = null;
    
    /**
     * @private
     * @type {Node}
     */
    this.mapOverlay_ = null;
    
    /**
     * @private
     * @type {Node}
     */
    this.staticOverlay_ = null;
    
    /**
     * @private
     * @type {Element}
     */
    this.container_ = null;
};
goog.inherits(ol.Map, goog.events.EventTarget);

/**
  @const
  @type {string}
*/
ol.Map.prototype.DEFAULT_PROJECTION = "EPSG:3857";
/**
  @const
  @type {string}
*/
ol.Map.prototype.DEFAULT_USER_PROJECTION = "EPSG:4326";
/**
  @const
  @type {number}
*/
ol.Map.ZOOM_FACTOR = 2;
/**
  @const
  @type {number}
*/
ol.Map.DEFAULT_TILE_SIZE = 256;
/**
  @const
  @type {Array.<string>}
 */
ol.Map.DEFAULT_CONTROLS = ["attribution", "zoom"];

/**
 * @return {ol.Loc} Map center in map projection.
 */
ol.Map.prototype.getCenter = function() {
    return this.center_;
};


/**
 * @return {!ol.Projection} Projection.
 */
ol.Map.prototype.getProjection = function() {
    if (goog.isNull(this.projection_)) {
        this.projection_ = new ol.Projection(this.DEFAULT_PROJECTION);
    }
    return this.projection_;
};


/**
 * @return {!ol.Projection} User projection.
 */
ol.Map.prototype.getUserProjection = function() {
    if (goog.isNull(this.userProjection_)) {
        this.userProjection_ = new ol.Projection(this.DEFAULT_USER_PROJECTION);
    }
    return this.userProjection_;
};


/**
 * @return {number|undefined} Zoom.
 */
ol.Map.prototype.getZoom = function() {
    return this.zoom_;
};


/**
 * @return {number} number of zoom levels.
 */
ol.Map.prototype.getNumZoomLevels = function() {
    return this.numZoomLevels_;
};


/**
 * @return {Array|undefined} array of resolutions available for this map
 */
ol.Map.prototype.getResolutions = function() {
    return this.resolutions_;
};


/**
 * @return {Array|undefined} array of layers available for this map
 */
ol.Map.prototype.getLayers = function() {
    return this.layers_;
};


/**
 * @return {Array.<ol.control.Control>}
 */
ol.Map.prototype.getControls = function() {
    return this.controls_;
};


/**
 * @return {ol.Bounds} the maxExtent for the map
 */
ol.Map.prototype.getMaxExtent = function() {
    if (goog.isDefAndNotNull(this.maxExtent_)) {
        return this.maxExtent_;
    } else {
        var projection = this.getProjection();
        var extent = projection.getExtent();
        if (goog.isDefAndNotNull(extent)) {
            extent = new ol.Bounds(
                extent.getMinX(), extent.getMinY(),
                extent.getMaxX(), extent.getMaxY());
            extent.setProjection(projection);
            return extent;
        } else {
            throw('maxExtent must be defined either in the map or the projection');
        }
    }
};


/**
 * @return {number} the max resolution for the map
 */
ol.Map.prototype.getMaxResolution = function() {
    if (goog.isDefAndNotNull(this.maxResolution_)) {
        return this.maxResolution_;
    } else {
        var extent = this.getMaxExtent();
        var dim = Math.max(
            (extent.getMaxX()-extent.getMinX()),
            (extent.getMaxY()-extent.getMinY())
         );
        return dim/ol.Map.DEFAULT_TILE_SIZE;
    }
};


/**
 * @param {number} zoom the zoom level being requested
 * @return {number} the resolution for the map at the given zoom level
 */
ol.Map.prototype.getResolutionForZoom = function(zoom) {
    if (goog.isDefAndNotNull(this.resolutions_)) {
        return this.resolutions_[zoom];
    } else {
        var maxResolution = this.getMaxResolution();
        return maxResolution/Math.pow(ol.Map.ZOOM_FACTOR, zoom);
    }
};

/**
 * @return {number} the resolution for the map at the given zoom level
 */
ol.Map.prototype.getResolution = function() {
    goog.asserts.assert(goog.isDef(this.renderer_));
    return this.renderer_.getResolution();
};


/**
 * TODO: We'll have to ask the map overlay renderer for this.  This method will
 * not work once map space is not aligned with pixel space.
 *
 * @param {goog.math.Coordinate|{x: number, y: number}} pixel
 * @return {ol.Loc}
 */
ol.Map.prototype.getLocForViewportPixel = function(pixel) {
    var size = this.getViewportSize();
    var center = this.center_;
    var resolution = this.getResolution();
    var x = center.getX() + (resolution * (pixel.x - (size.width / 2)));
    var y = center.getY() - (resolution * (pixel.y - (size.height / 2)));
    return new ol.Loc(x, y, undefined, this.getProjection());
};

/**
 * TODO: We'll have to ask the map overlay renderer for this.  This method will
 * not work once map space is not aligned with pixel space.
 *
 * @param {ol.Loc} loc
 * @return {{x: number, y: number}}
 */
ol.Map.prototype.getViewportPixelForLoc = function(loc) {
    var size = this.getViewportSize();
    var center = this.center_;
    var resolution = this.getResolution();
    return {
        x: ((loc.getX() - center.getX()) / resolution) + (size.width / 2),
        y: ((center.getY() - loc.getY()) / resolution) + (size.height / 2)
    };
};

/**
 * @return {goog.math.Size}
 */
ol.Map.prototype.getViewportSize = function() {
    // TODO: listen for resize and set this.viewportSize_ null
    // https://github.com/openlayers/ol3/issues/2
    if (goog.isNull(this.viewportSize_)) {
        this.viewportSize_ = goog.style.getSize(this.viewport_);
    }
    return this.viewportSize_;
};

/**
 * @param {ol.Loc} center Center in map projection.
 */
ol.Map.prototype.setCenter = function(center) {
    goog.asserts.assert(!goog.isNull(center.getProjection()));
    this.center_ = center.doTransform(this.getProjection());
    this.conditionallyRender();
};


/**
 * @param {ol.Loc} center
 * @param {number} zoom
 */
ol.Map.prototype.setCenterAndZoom = function(center, zoom) {
    goog.asserts.assert(!goog.isNull(center.getProjection()));
    this.center_ = center.doTransform(this.getProjection());
    this.zoom_ = this.limitZoom(zoom);
    this.conditionallyRender();
};


/**
 * @param {number} zoom The zoom level to zoom to
 * @param {goog.math.Coordinate|{x: number, y: number}=} opt_anchor
 *     Optional anchor pixel for the zoom origin.
 */
ol.Map.prototype.setZoom = function(zoom, opt_anchor) {
    var currentZoom = this.zoom_,
        newZoom = this.limitZoom(zoom),
        newCenter;
    if (newZoom === currentZoom) {
        return;
    }
    if (goog.isDef(opt_anchor)) {
        var size = this.getViewportSize(),
            anchorLoc = this.getLocForViewportPixel(opt_anchor),
            newRes = this.getResolutionForZoom(newZoom);
        newCenter = anchorLoc.add(
            (size.width/2 - opt_anchor.x) * newRes,
            (opt_anchor.y - size.height/2) * newRes
        );
    } else {
        newCenter = this.center_;
    }
    this.setCenterAndZoom(newCenter, newZoom);
};


/**
 * @param {ol.Projection} projection Projection.
 */
ol.Map.prototype.setProjection = function(projection) {
    this.projection_ = projection;
};


/**
 * @param {ol.Projection} userProjection set the user projection.
 */
ol.Map.prototype.setUserProjection = function(userProjection) {
    this.userProjection_ = userProjection;
};


/**
 * @param {number} zoom
 * @return {number} zoom clamped to the range of available zoom levels.
 */
ol.Map.prototype.limitZoom = function(zoom) {
    return goog.math.clamp(zoom, 0, this.getNumZoomLevels()-1);
};


/**
 * @param {number} nZoom Zoom.
 */
ol.Map.prototype.setNumZoomLevels = function(nZoom) {
    this.numZoomLevels_ = nZoom;
};

/**
 * @param {Array} resolutions the map resolutions if set on the map
 */
ol.Map.prototype.setResolutions = function(resolutions) {
    this.resolutions_ = resolutions;
};

/**
 * @param {Array} layers the layers set on the map
 */
ol.Map.prototype.setLayers = function(layers) {
    //TODO remove layers properly if there are layers already
    this.layers_ = [];
    this.addLayers(layers);
};

ol.Map.prototype.addLayers = function(layers) {
    var layer;
    for (var i=0, ii=layers.length; i<ii; ++i) {
        layer = layers[i];
        this.layers_.push(layer);
        goog.events.dispatchEvent(this, {type: 'layeradd', 'layer': layer});
    }
    this.conditionallyRender();
};


/**
 * @param {Array.<ol.control.Control>|undefined} opt_controls
 */
ol.Map.prototype.setControls = function(opt_controls) {
    if (!this.controls_) {
        var control;
        for (var i=0, ii=opt_controls.length; i<ii; ++i) {
            control = opt_controls[i];
            if (!(control instanceof ol.control.Control)) {
                control = new ol.control.CONTROL_MAP[control]();
            }
            control.setMap(this);
        }
        this.controls_ = opt_controls;
    }
};

/**
 * @param {ol.Bounds} extent the maxExtent for the map
 */
ol.Map.prototype.setMaxExtent = function(extent) {
    this.maxExtent_ = extent;
};

/**
 * @param {number} maxResolution the max resolution for the map
 */
ol.Map.prototype.setMaxResolution = function(maxResolution) {
    this.maxResolution_ = maxResolution;
};

/**
 * @param {Element} container the container to render the map to
 */
ol.Map.prototype.setContainer = function(container) {
    this.container_ = container;
    this.setViewport();
    this.createRenderer();
    //TODO Controls could be set earlier, but we need to deal with content that
    // controls place on overlays.
    this.setControls(ol.Map.DEFAULT_CONTROLS);
    // conditionally render
    this.conditionallyRender();
};

/**
 * Check if everything is ready.  Render if so.
 */
ol.Map.prototype.conditionallyRender = function() {
    if (goog.isDef(this.renderer_) && !goog.isNull(this.layers_) &&
       goog.isDef(this.zoom_) && !goog.isNull(this.center_)) {
        this.renderer_.draw(this.layers_, this.center_,
            this.getResolutionForZoom(this.zoom_)
        );
    }
};

/**
 * @return {Element}
 */
ol.Map.prototype.getViewport = function() {
    return this.viewport_;
};

ol.Map.prototype.setViewport = function() {
    if (!this.viewport_) {
        this.viewport_ = /** @type {Element} */ (goog.dom.createDom('div', {
            'class': 'ol-viewport',
            'style': 'width:100%;height:100%;top:0;left:0;position:relative;overflow:hidden'
        }));
        this.initHandlers();
    }
    goog.dom.appendChild(this.container_, this.viewport_);
};

/**
 * Init the map event handlers.
 */
ol.Map.prototype.initHandlers = function() {
    goog.asserts.assert(!goog.isNull(this.viewport_));

    var handler,
        states = /** @type {ol.handler.states} */ ({});

    if (ol.ENABLE_DRAG_HANDLER) {
        handler = new ol.handler.Drag(this, states);
        this.registerDisposable(handler);
    }
    if (ol.ENABLE_MOUSEWHEEL_HANDLER) {
        handler = new ol.handler.MouseWheel(this, states);
        this.registerDisposable(handler);
    }
    if (ol.ENABLE_CLICK_HANDLER) {
        handler = new ol.handler.Click(this, states);
        this.registerDisposable(handler);
    }
};

ol.Map.prototype.createRenderer = function() {
    var Renderer = ol.renderer.MapRenderer.pickRendererType(
        ol.Map.preferredRenderers);
    this.renderer_ = new Renderer(this.viewport_);
    
    //TODO Consider making a renderer responsible for managing the overlays
    var viewport = this.viewport_;
    if (!this.mapOverlay_ && !this.staticOverlay_) {
        var staticCls = 'ol-overlay-static';
        this.mapOverlay_ = goog.dom.createDom('div', 'ol-overlay-map');
        this.staticOverlay_ = goog.dom.createDom('div', {
            'class': staticCls,
            'style': 'width:100%;height:100%;top:0;left:0;position:absolute;z-index:1'
        });
    }
    if (!goog.isNull(viewport)) {
        goog.dom.append(viewport, this.mapOverlay_, this.staticOverlay_);
    } 
};

/**
 * TODO: This method will need to be reworked/revisited when renderers can
 * display a map that is rotated or otherwise not aligned with pixel space.
 *
 * @param {number} dx pixels to move in x direction
 * @param {number} dy pixels to move in x direction
 */
ol.Map.prototype.moveByViewportPx = function(dx, dy) {
    if (!goog.isNull(this.center_) && goog.isDef(this.zoom_)) {
        var resolution = this.getResolutionForZoom(this.zoom_),
            center = new ol.Loc(
                this.center_.getX() - dx * resolution,
                this.center_.getY() + dy * resolution
            );
            center.setProjection(this.getProjection());
        this.setCenter(center);
    }
};

ol.Map.prototype.zoomIn = function() {
    this.setZoom(this.zoom_+1);
};

ol.Map.prototype.zoomOut = function() {
    this.setZoom(this.zoom_-1);
};

/**
 * @returns {Node} the map overlay element
 */
ol.Map.prototype.getMapOverlay = function() {
    return this.mapOverlay_;
};

/**
 * @returns {Node} the static overlay element
 */
ol.Map.prototype.getStaticOverlay = function() {
    return this.staticOverlay_;
};

/**
 * @inheritDoc
 */
ol.Map.prototype.disposeInternal = function() {
    goog.base(this, 'disposeInternal');
    //remove layers, etc.
    for (var key in this) {
        delete this[key];
    }
};


/**
 * List of preferred renderer types.  Map renderers have a getType method
 * that returns a string describing their type.  This list determines the 
 * preferences for picking a layer renderer.
 *
 * @type {Array.<string>}
 */
ol.Map.preferredRenderers = ["webgl", "canvas"];