Abstracted scan status card

Added additional enums to TicketStatus and a separate widget for ticket scan status cards.

lib/pages/scan_barcode_page.dart

@@ -6,6 +6,7 @@ import 'package:barcode_scan/barcode_scan.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
 import '../utils/ticket_status_enum.dart';
 import '../utils/colours.dart';
+import '../widgets/scanned_ticket_card.dart';
 
 class ScanBarcodePage extends StatefulWidget {
 
@@ -19,7 +20,8 @@ class ScanBarcodePage extends StatefulWidget {
 
 class ScanBarcodePageState extends State<ScanBarcodePage>{
 
-  List<List> scannedTickets = []; //[Name, Status, Pass]
+  // TODO: make scanned tickets collection in firestore, but only show messages from current device when scanning (i.e. it will appear the same to the user but there will be a log of all scans)
+  List<Map<String, dynamic>> scannedTickets = []; //[Name, Status, Pass]
 
   ///Validates the ticket with [qrContent] against the database
   ///
@@ -32,31 +34,41 @@ class ScanBarcodePageState extends State<ScanBarcodePage>{
     List<String> qrContentArray = qrContent.split(",");
     if(qrContentArray[0] != widget._eventId) {
       this.setState(() {
-        scannedTickets.add(["Ticket Lookup Failed", "This ticket is for a different event", TicketStatus.Unverified]);
-
+        scannedTickets.add({"TicketStatus": TicketStatus.DifferentEvent});
       });
-      return; // ignore: return_without_value
+      return;
     }
     Firestore.instance.document("events/" + qrContentArray[0] + "/attendees/" + qrContentArray[1]).get().then((DocumentSnapshot attendeeSnapshot) {
+      if(attendeeSnapshot.data == null) {
+        this.setState(() {
+          scannedTickets.add({"TicketStatus": TicketStatus.UnknownUser});
+        });
+        return;
+      }
       Firestore.instance.document("users/" + qrContentArray[1]).get().then((DocumentSnapshot userSnapshot) {
         String name = userSnapshot.data["FirstName"] + " " + userSnapshot.data["LastName"];
         this.setState(() {
           if(qrContentArray[2] == attendeeSnapshot.data["EntryCode"] && attendeeSnapshot.data["Entered"] == false){
-            scannedTickets.add([name, "Ticket Verified", TicketStatus.Verified]);
+            scannedTickets.add({"Name": name, "TicketStatus": TicketStatus.Verified});
             Firestore.instance.document("events/" + qrContentArray[0] + "/attendees/" + qrContentArray[1]).updateData({"Entered": true});
             // TODO: set Entered to true
           } else if(qrContentArray[2] == attendeeSnapshot.data["EntryCode"] && attendeeSnapshot.data["Entered"] == true){
-            scannedTickets.add([name, "Ticket Verification Failed: Guest has already entered", TicketStatus.Unverified]);
+            scannedTickets.add({"Name": name, "TicketStatus": TicketStatus.AlreadyScanned});
           } else {
-            scannedTickets.add([name, "Ticket Verification Failed: Invalid Ticket", TicketStatus.Unverified]);
+            scannedTickets.add({"Name": name, "TicketStatus": TicketStatus.InvalidEntryCode});
           }
         });
       }).catchError((Error error) {
         this.setState(() {
-          this.setState(() => scannedTickets.add(["Ticket Lookup Failed", "The user doesn't exist or cannot attend this event", TicketStatus.Unverified]));
+          scannedTickets.add({"TicketStatus": TicketStatus.UnknownUser});
         });
         print(error);
       });
+    }).catchError((Error error) {
+      print("Catching error...");
+      this.setState(() {
+        scannedTickets.add({"TicketStatus": TicketStatus.UnknownUser});
+      });
     });
 
   }
@@ -79,15 +91,7 @@ class ScanBarcodePageState extends State<ScanBarcodePage>{
                 itemCount: scannedTickets.length,
                 itemBuilder: (BuildContext context, int index) {
                   index = scannedTickets.length - index -  1;
-                  return new Card(
-                    child: new ListTile(
-                      leading: scannedTickets[index][2] == TicketStatus.Verified
-                          ? const Icon(Icons.check, color: Colors.greenAccent,) : const Icon(Icons.clear, color: Colors.white),
-                      title: new Text(scannedTickets[index][0]),
-                      subtitle: new Text(scannedTickets[index][1]),
-                    ),
-                    color: scannedTickets[index][2] == TicketStatus.Verified ? Colors.white : scannedTickets[index][2] == TicketStatus.ScanFailed ? AppColours.warning : AppColours.error,
-                  );
+                  return new ScannedTicketCard(scannedTickets[index]);
                 }
               ),
             )
@@ -104,15 +108,15 @@ class ScanBarcodePageState extends State<ScanBarcodePage>{
     } on PlatformException catch (e) {
       if (e.code == BarcodeScanner.CameraAccessDenied) {
         setState(() {
-          this.scannedTickets.add(['Scan Failed', 'Unable to access the camera.', TicketStatus.ScanFailed]);
+          this.scannedTickets.add({"TicketStatus": TicketStatus.UnableToAccessCamera});
         });
       } else {
-        setState(() => this.scannedTickets.add(['Scan Failed', 'Unknown error: $e', TicketStatus.ScanFailed]));
+        setState(() => this.scannedTickets.add({"TicketStatus": TicketStatus.ScanFailed, "ErrorMessage": e}));
       }
     } on FormatException{
-      setState(() => this.scannedTickets.add(['Scan Failed', 'Exited scanning before scanning a ticket', TicketStatus.ScanFailed]));
+      setState(() => this.scannedTickets.add({"TicketStatus": TicketStatus.ExitedScan}));
     } catch (e) {
-      setState(() => this.scannedTickets.add(['Scan Failed', 'Unknown error: $e', TicketStatus.ScanFailed]));
+      setState(() => this.scannedTickets.add({"TicketStatus": TicketStatus.ScanFailed, "ErrorMessage": e}));
     }
   }
 

lib/utils/ticket_status_enum.dart

@@ -1,3 +1,5 @@
 enum TicketStatus {
-  Verified, Unverified, ScanFailed
+  Verified,
+  AlreadyScanned, UnknownUser, InvalidEntryCode, DifferentEvent,
+  ExitedScan, ScanFailed, UnableToAccessCamera
 }

lib/widgets/scanned_ticket_card.dart

@@ -0,0 +1,65 @@
+import 'package:flutter/material.dart';
+import '../utils/ticket_status_enum.dart';
+import '../utils/colours.dart';
+
+class ScannedTicketCard extends StatelessWidget {
+  final Map<String, dynamic> ticketScan;
+
+  ScannedTicketCard(this.ticketScan);
+
+  final Map<TicketStatus, String> errorCardTitles = <TicketStatus, String> {
+    TicketStatus.DifferentEvent: "Different Event",
+    TicketStatus.UnknownUser: "Unkown Guest",
+    TicketStatus.UnableToAccessCamera: "Unable to Access Camera",
+    TicketStatus.ExitedScan: "Exited Scan",
+    TicketStatus.ScanFailed: "Unknown Scan Error"
+  };
+
+  final Map<TicketStatus, String> errorCardDescriptions = <TicketStatus, String> {
+    TicketStatus.AlreadyScanned: "This guest has already entered",
+    TicketStatus.DifferentEvent: "This ticket is for a different event",
+    TicketStatus.UnknownUser: "The scanned ticket does not belong to a guest going to this event",
+    TicketStatus.InvalidEntryCode: "The scanned ticket belongs to a guest going to this event, but the security information was not valid",
+    TicketStatus.UnableToAccessCamera: "Ensure that the camera permissions have been enabled",
+    TicketStatus.ExitedScan: "The scan was exited before a ticket was shown",
+    TicketStatus.ScanFailed: ""
+  };
+
+  @override
+  Widget build(BuildContext context) {
+    String cardTitle;
+    String cardDescription;
+    bool ticketVerified = false;
+    bool scanError = false;
+
+    if (ticketScan["TicketStatus"] == TicketStatus.Verified) {
+      cardTitle = ticketScan["Name"];
+      cardDescription = "Entry verified";
+      ticketVerified = true;
+    } else if (ticketScan["TicketStatus"] == TicketStatus.AlreadyScanned || ticketScan["TicketStatus"] == TicketStatus.InvalidEntryCode) {
+      cardTitle = ticketScan["Name"];
+      cardDescription = errorCardDescriptions[ticketScan["TicketStatus"]];
+    } else {
+      cardTitle = errorCardTitles[ticketScan["TicketStatus"]];
+      cardDescription = errorCardDescriptions[ticketScan["TicketStatus"]];
+    }
+
+    if(ticketScan["TicketStatus"] == TicketStatus.UnableToAccessCamera || ticketScan["TicketStatus"] == TicketStatus.ExitedScan || ticketScan["TicketStatus"] == TicketStatus.ScanFailed) {
+      scanError = true;
+    }
+
+
+    return new Card(
+      child: new ListTile(
+        leading: ticketVerified
+            ? const Icon(Icons.check, color: Colors.greenAccent,) : const Icon(Icons.clear, color: Colors.white),
+        title: new Text(cardTitle),
+        subtitle: new Text(cardDescription),
+      ),
+      color: ticketVerified ? Colors.white
+          : scanError ? AppColours.warning
+          : AppColours.error,
+    );
+  }
+
+}