purchase screen coupons list final

lib/screens/purchase.dart

@@ -219,44 +219,60 @@ class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
         purchaseInProgress = true;
 
         String token = await helper.getToken();
-        helper.getMerchantID().then((result) {
-          helper.getCurrency().then((currency) {
-            var body = {
-              'doc_id': result,
-              'curr_iso_code': currency.toString(),
-              'commit': 'true',
-              'sum_total': sumTotal
-            };
+        var result = await helper.getMerchantID();
+        var currency = await helper.getCurrency();
 
-            getPurchaseRequest(user['purchases_url'], body, token)
-                .then((response) {
-              print(response.body);
-              Map parsedMap = JSON.decode(response.body);
+        var body = {
+          'doc_id': result,
+          'curr_iso_code': currency.toString(),
+          'commit': 'true',
+          'sum_total': sumTotal
+        };
 
-              Navigator.of(context).pop();
+        var purchaseResponse;
 
-              if (parsedMap.containsKey('errors')) {
-                List<String> errors = parsedMap['errors'];
-                Scaffold
-                    .of(context)
-                    .showSnackBar(new SnackBar(content: new Text(errors[0])));
-              } else {
-                pushRouteReplacement(
-                    context,
-                    new PurchaseSuccessScreen(
-                        sumTotal,
-                        user['first_name'] == null ? '' : user['first_name'],
-                        helper,
-                        app,
-                        parsedMap
-                    ));
-              }
-            }).catchError((error) {
-              purchaseInProgress = false;
-              print(error.toString());
-            });
-          });
-        });
+        try {
+          purchaseResponse = await getPurchaseRequest(user['purchases_url'], body, token);
+          print(purchaseResponse.body);
+        } catch(error) {
+          purchaseInProgress = false;
+          print(error.toString());
+        }
+
+        Map purchase = JSON.decode(purchaseResponse.body);
+
+        Navigator.of(context).pop();
+
+        if (purchase.containsKey('errors')) {
+          List<String> errors = purchase['errors'];
+          Scaffold
+            .of(context)
+            .showSnackBar(new SnackBar(content: new Text(errors[0])));
+        } else {
+          var couponsResponse;
+
+          try {
+            couponsResponse = await getCouponsRequest(purchase['coupons_url'], token);
+            print(couponsResponse.body);
+          } catch(error) {
+            purchaseInProgress = false;
+            print(error.toString());
+          }
+
+          Map coupons = JSON.decode(couponsResponse.body);
+
+          pushRouteReplacement(
+            context,
+            new PurchaseSuccessScreen(
+              sumTotal,
+              user['first_name'] == null ? '' : user['first_name'],
+              helper,
+              app,
+              purchase,
+              coupons['results']
+            )
+          );
+        }
       }
     }
   }