add directions url

@@ -25,6 +25,7 @@ class MapsViewController: UIViewController, MKMapViewDelegate {
     // public
     public var couponSet: swiftApi.CouponSetItemModel?
     var merchantsArray:Array<swiftApi.MerchantModel> = []
+    var selectedMerchant: swiftApi.MerchantModel?
     
     //
     var loading: Bool = false
@@ -112,6 +113,24 @@ class MapsViewController: UIViewController, MKMapViewDelegate {
     
     @IBAction func directionsButtomAction(_ sender: Any) {
         
+        guard let lon = selectedMerchant?._longitude, let lat = selectedMerchant?._latitude  else {
+            return
+        }
+        
+        // guard your URL instances
+        guard let googleMapsUrl = URL(string: String(format: "https://www.google.com/maps/@%.6f,%.6f,6z", lat, lon)),
+              let appleMapsUrl = URL(string: String(format: "http://maps.apple.com/?ll=%.6f,%.6f", lat, lon)) else {
+                  print("Error creating URLs")
+                  return
+            }
+
+        // check if link can be opened with google maps.
+        guard UIApplication.shared.canOpenURL(googleMapsUrl) else {
+            UIApplication.shared.open(appleMapsUrl, options: [:], completionHandler: nil)
+            return
+        }
+        
+        UIApplication.shared.open(googleMapsUrl, options: [:], completionHandler: nil)
     }
     
     private func loadMapPins() {
@@ -122,6 +141,8 @@ class MapsViewController: UIViewController, MKMapViewDelegate {
     }
     
     private func loadPinDetailsView(_ annotation: MerchantAnnotation) {
+        self.selectedMerchant = annotation.model
+        
         self.titleView.text = "INTERSPORT"
         self.nameImageView.image = UIImage(named: "intersport")
         self.nameView.text = "Intersport Χαλάνδρι"
@@ -138,6 +159,8 @@ class MapsViewController: UIViewController, MKMapViewDelegate {
     }
     
     private func hidePinDetailsView() {
+        self.selectedMerchant = nil
+        
         self.infoTopConstraint.constant = 0
         UIView.animate(withDuration: 2.0) {
             self.view.layoutIfNeeded()