 import SideMenu
 import FBSDKLoginKit
 import Firebase
+
+enum MainViewControllerConstants {
+    static let kDefaultMapAreaLen: Double = 40.0
+}
 
 // TODO - MapView initial height should be proportional to device height
 // TODO - Define a CLCicularRegion based on user's current location and update store map and list when user leaves that region

                let newLoc = CLLocation(latitude: (mapLocation?.latitude)!, longitude: (mapLocation?.longitude)!)
                let previousLoc = CLLocation(latitude: previousMapLocation.latitude, longitude: previousMapLocation.longitude)
                self.deltaMapDragDistance += newLoc.distance(from: previousLoc) * 0.000621371
                
                NSLog("delta drag distance: \(self.deltaMapDragDistance)")
                NSLog(".25*mapLat: \(0.25*mapArea.latDelta!)")
                
                if self.deltaMapDragDistance > 0.25 * mapArea.latDelta! { // miles
                    searchThisAreaBtn.isHidden = false

        let availableScreenHt = screenSize.height - 64.0
        self.mapViewYConstraint.constant = 0
        self.mapViewHeightConstraint.constant = availableScreenHt * 0.5
        mapArea.latDelta = MainViewControllerConstants.kDefaultMapAreaLen
        mapArea.longDelta = MainViewControllerConstants.kDefaultMapAreaLen
        mapView.mapType = .standard
        mapView.delegate = self
        
