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lib/models/expense.dart

@@ -1,20 +1,24 @@
 import '/models/frequency.dart';
 
 class Expense {
+  final int? id;
   final String name;
   final double cost;
   final Frequency frequency;
   final String description;
 
-  const Expense(
-      {required this.name,
-      required this.cost,
-      required this.frequency,
-      required this.description});
+  const Expense({
+    this.id,
+    required this.name,
+    required this.cost,
+    required this.frequency,
+    required this.description,
+  });
 
   @override
   String toString() {
-    return "$name, $cost, ${frequency.title}, $description";
+    //return "$name, $cost, ${frequency.title}, $description";
+    return toMap().toString();
   }
 
   double calcComparableCost() {
@@ -24,4 +28,24 @@ class Expense {
   double calcComparableCostDaily() {
     return cost / frequency.numDays;
   }
+
+  factory Expense.fromMap(Map<String, dynamic> json) => Expense(
+        id: json['id'],
+        name: json['name'],
+        cost: json['cost'],
+        frequency: Frequency.values
+            .where((expense) => expense.title == json['frequency'])
+            .first,
+        description: json['description'],
+      );
+
+  Map<String, dynamic> toMap() {
+    return {
+      'id': id,
+      'name': name,
+      'cost': cost,
+      'frequency': frequency.title,
+      'description': description,
+    };
+  }
 }