refactor(model): extract shorter JSON field names

lib/model/booking.dart

@@ -5,6 +5,15 @@ import 'package:cabin_booking/utils/time_of_day_extension.dart';
 import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 
+abstract class _JsonFields {
+  static const description = 'de';
+  static const date = 'd';
+  static const startTime = 'st';
+  static const endTime = 'et';
+  static const status = 's';
+  static const isLocked = 'il';
+}
+
 class Booking extends Item {
   String? description;
   DateTime? date;
@@ -33,23 +42,25 @@ class Booking extends Item {
   }) : super(id: id);
 
   Booking.from(Map<String, dynamic> other)
-      : description = other['description'] as String?,
-        date = DateTime.tryParse(other['date'] as String),
-        startTime = TimeOfDayExtension.tryParse(other['startTime'] as String),
-        endTime = TimeOfDayExtension.tryParse(other['endTime'] as String),
-        status = BookingStatus.values[other['status'] as int],
-        isLocked = other['isLocked'] as bool,
+      : description = other[_JsonFields.description] as String?,
+        date = DateTime.tryParse(other[_JsonFields.date] as String),
+        startTime =
+            TimeOfDayExtension.tryParse(other[_JsonFields.startTime] as String),
+        endTime =
+            TimeOfDayExtension.tryParse(other[_JsonFields.endTime] as String),
+        status = BookingStatus.values[other[_JsonFields.status] as int],
+        isLocked = other[_JsonFields.isLocked] as bool,
         super.from(other);
 
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'description': description,
-        'date': date!.toIso8601String().split('T').first,
-        'startTime': startTime!.format24Hour(),
-        'endTime': endTime!.format24Hour(),
-        'status': status.index,
-        'isLocked': isLocked,
+        _JsonFields.description: description,
+        _JsonFields.date: date!.toIso8601String().split('T').first,
+        _JsonFields.startTime: startTime!.format24Hour(),
+        _JsonFields.endTime: endTime!.format24Hour(),
+        _JsonFields.status: status.index,
+        _JsonFields.isLocked: isLocked,
       };
 
   DateTime get startDateTime => date!.addTimeOfDay(startTime);

lib/model/cabin.dart

@@ -6,6 +6,13 @@ import 'package:cabin_booking/model/item.dart';
 import 'package:cabin_booking/model/recurring_booking.dart';
 import 'package:flutter/material.dart';
 
+abstract class _JsonFields {
+  static const number = 'n';
+  static const elements = 'e';
+  static const bookings = 'b';
+  static const recurringBookings = 'rb';
+}
+
 class Cabin extends Item {
   int number;
   late CabinElements elements;
@@ -26,23 +33,25 @@ class Cabin extends Item {
   }
 
   Cabin.from(Map<String, dynamic> other)
-      : number = other['number'] as int,
+      : number = other[_JsonFields.number] as int,
         elements = CabinElements.from(
-          other['elements'] as Map<String, dynamic>,
+          other[_JsonFields.elements] as Map<String, dynamic>,
         ),
         _bookingManager = BookingManager.from(
-          bookings: other['bookings'] as List<dynamic>,
-          recurringBookings: other['recurringBookings'] as List<dynamic>,
+          bookings: other[_JsonFields.bookings] as List<dynamic>,
+          recurringBookings:
+              other[_JsonFields.recurringBookings] as List<dynamic>,
         ),
         super.from(other);
 
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'number': number,
-        'elements': elements.toJson(),
-        'bookings': _bookingManager.bookingsToJson(),
-        'recurringBookings': _bookingManager.recurringBookingsToJson(),
+        _JsonFields.number: number,
+        _JsonFields.elements: elements.toJson(),
+        _JsonFields.bookings: _bookingManager.bookingsToJson(),
+        _JsonFields.recurringBookings:
+            _bookingManager.recurringBookingsToJson(),
       };
 
   Cabin simplified() => Cabin(id: id, number: number);

lib/model/cabin_elements/cabin_elements.dart

@@ -1,3 +1,12 @@
+import 'package:cabin_booking/model/cabin_elements/piano.dart';
+
+abstract class _JsonFields {
+  static const pianos = 'p';
+  static const lecterns = 'l';
+  static const chairs = 'c';
+  static const tables = 't';
+}
+
 class CabinElements {
   late List<Piano> pianos;
   int lecterns;
@@ -14,40 +23,17 @@ class CabinElements {
   }
 
   CabinElements.from(Map<String, dynamic> other)
-      : pianos = (other['pianos'] as List<dynamic>)
+      : pianos = (other[_JsonFields.pianos] as List<dynamic>)
             .map((piano) => Piano.from(piano))
             .toList(),
-        lecterns = other['lecterns'] as int,
-        chairs = other['chairs'] as int,
-        tables = other['tables'] as int;
-
-  Map<String, dynamic> toJson() => {
-        'pianos': pianos.map((piano) => piano.toJson()).toList(),
-        'lecterns': lecterns,
-        'chairs': chairs,
-        'tables': tables,
-      };
-}
-
-class Piano {
-  String? brand;
-  String? model;
-  bool isElectronic;
-
-  Piano({
-    this.brand,
-    this.model,
-    this.isElectronic = false,
-  });
-
-  Piano.from(Map<String, dynamic> other)
-      : brand = other['brand'] as String?,
-        model = other['model'] as String?,
-        isElectronic = other['isElectronic'] as bool;
+        lecterns = other[_JsonFields.lecterns] as int,
+        chairs = other[_JsonFields.chairs] as int,
+        tables = other[_JsonFields.tables] as int;
 
   Map<String, dynamic> toJson() => {
-        'brand': brand,
-        'model': model,
-        'isElectronic': isElectronic,
+        _JsonFields.pianos: pianos.map((piano) => piano.toJson()).toList(),
+        _JsonFields.lecterns: lecterns,
+        _JsonFields.chairs: chairs,
+        _JsonFields.tables: tables,
       };
 }

lib/model/cabin_elements/piano.dart

@@ -0,0 +1,28 @@
+abstract class _JsonFields {
+  static const brand = 'b';
+  static const model = 'm';
+  static const isElectronic = 'ie';
+}
+
+class Piano {
+  String? brand;
+  String? model;
+  bool isElectronic;
+
+  Piano({
+    this.brand,
+    this.model,
+    this.isElectronic = false,
+  });
+
+  Piano.from(Map<String, dynamic> other)
+      : brand = other[_JsonFields.brand] as String?,
+        model = other[_JsonFields.model] as String?,
+        isElectronic = other[_JsonFields.isElectronic] as bool;
+
+  Map<String, dynamic> toJson() => {
+        _JsonFields.brand: brand,
+        _JsonFields.model: model,
+        _JsonFields.isElectronic: isElectronic,
+      };
+}

lib/model/date_range.dart

@@ -2,6 +2,11 @@ import 'package:cabin_booking/model/item.dart';
 import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 
+abstract class _JsonFields {
+  static const startDate = 'sd';
+  static const endDate = 'ed';
+}
+
 class DateRange extends Item {
   DateTime? startDate;
   DateTime? endDate;
@@ -18,15 +23,15 @@ class DateRange extends Item {
   }
 
   DateRange.from(Map<String, dynamic> other)
-      : startDate = DateTime.tryParse(other['startDate'] as String),
-        endDate = DateTime.tryParse(other['endDate'] as String),
+      : startDate = DateTime.tryParse(other[_JsonFields.startDate] as String),
+        endDate = DateTime.tryParse(other[_JsonFields.endDate] as String),
         super.from(other);
 
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'startDate': startDate!.toIso8601String().split('T').first,
-        'endDate': endDate!.toIso8601String().split('T').first,
+        _JsonFields.startDate: startDate!.toIso8601String().split('T').first,
+        _JsonFields.endDate: endDate!.toIso8601String().split('T').first,
       };
 
   @override

lib/model/holiday.dart

@@ -1,5 +1,9 @@
 import 'package:cabin_booking/model/date_range.dart';
 
+abstract class _JsonFields {
+  static const kind = 'k';
+}
+
 class Holiday extends DateRange {
   final HolidayKind kind;
 
@@ -15,13 +19,13 @@ class Holiday extends DateRange {
         );
 
   Holiday.from(Map<String, dynamic> other)
-      : kind = HolidayKind.values[other['kind'] as int],
+      : kind = HolidayKind.values[other[_JsonFields.kind] as int],
         super.from(other);
 
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'kind': kind.index,
+        _JsonFields.kind: kind.index,
       };
 }
 

lib/model/item.dart

@@ -2,6 +2,13 @@ import 'package:cabin_booking/model/serializable.dart';
 import 'package:flutter/material.dart';
 import 'package:uuid/uuid.dart';
 
+abstract class _JsonFields {
+  static const id = 'id';
+  static const creationDateTime = 'cdt';
+  static const modificationDateTime = 'mdt';
+  static const modificationCount = 'mc';
+}
+
 abstract class Item implements Comparable<Item>, Serializable {
   late String id;
   final DateTime creationDateTime;
@@ -15,22 +22,26 @@ abstract class Item implements Comparable<Item>, Serializable {
   }
 
   Item.from(Map<String, dynamic> other)
-      : id = other['id'] as String,
+      : id = other[_JsonFields.id] as String,
         creationDateTime =
-            DateTime.tryParse(other['creationDateTime'] as String)!,
-        modificationDateTime = other.containsKey('modificationDateTime')
-            ? DateTime.tryParse(other['modificationDateTime'] as String)
-            : null,
-        modificationCount = other['modificationCount'] as int;
+            DateTime.tryParse(other[_JsonFields.creationDateTime] as String)!,
+        modificationDateTime =
+            other.containsKey(_JsonFields.modificationDateTime)
+                ? DateTime.tryParse(
+                    other[_JsonFields.modificationDateTime] as String,
+                  )
+                : null,
+        modificationCount = other[_JsonFields.modificationCount] as int;
 
   @override
   @mustCallSuper
   Map<String, dynamic> toJson() => {
-        'id': id,
-        'creationDateTime': creationDateTime.toIso8601String(),
+        _JsonFields.id: id,
+        _JsonFields.creationDateTime: creationDateTime.toIso8601String(),
         if (modificationDateTime != null)
-          'modificationDateTime': modificationDateTime!.toIso8601String(),
-        'modificationCount': modificationCount,
+          _JsonFields.modificationDateTime:
+              modificationDateTime!.toIso8601String(),
+        _JsonFields.modificationCount: modificationCount,
       };
 
   Item copyWith();

lib/model/recurring_booking.dart

@@ -2,6 +2,13 @@ import 'package:cabin_booking/model/booking.dart';
 import 'package:collection/collection.dart' show IterableExtension;
 import 'package:flutter/material.dart';
 
+abstract class _JsonFields {
+  static const periodicity = 'p';
+  static const repeatEvery = 're';
+  static const recurringEndDate = 'edt';
+  static const occurrences = 'o';
+}
+
 class RecurringBooking extends Booking {
   Periodicity periodicity;
   int repeatEvery;
@@ -37,13 +44,13 @@ class RecurringBooking extends Booking {
         );
 
   RecurringBooking.from(Map<String, dynamic> other)
-      : periodicity = Periodicity.values[other['periodicityIndex'] as int],
-        repeatEvery = other['repeatEvery'] as int,
-        _recurringEndDate = other.containsKey('endDate')
-            ? DateTime.tryParse(other['endDate'] as String)
+      : periodicity = Periodicity.values[other[_JsonFields.periodicity] as int],
+        repeatEvery = other[_JsonFields.repeatEvery] as int,
+        _recurringEndDate = other.containsKey(_JsonFields.recurringEndDate)
+            ? DateTime.tryParse(other[_JsonFields.recurringEndDate] as String)
             : null,
-        _occurrences = other.containsKey('occurrences')
-            ? other['occurrences'] as int?
+        _occurrences = other.containsKey(_JsonFields.occurrences)
+            ? other[_JsonFields.occurrences] as int?
             : null,
         super.from(other);
 
@@ -73,12 +80,13 @@ class RecurringBooking extends Booking {
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'periodicityIndex': periodicity.index,
-        'repeatEvery': repeatEvery,
+        _JsonFields.periodicity: periodicity.index,
+        _JsonFields.repeatEvery: repeatEvery,
         if (method == RecurringBookingMethod.endDate)
-          'endDate': _recurringEndDate!.toIso8601String().split('T').first
+          _JsonFields.recurringEndDate:
+              _recurringEndDate!.toIso8601String().split('T').first
         else if (method == RecurringBookingMethod.occurrences)
-          'occurrences': _occurrences,
+          _JsonFields.occurrences: _occurrences,
       };
 
   RecurringBookingMethod get method => _recurringEndDate != null

lib/model/school_year.dart

@@ -4,6 +4,10 @@ import 'package:cabin_booking/model/date_range.dart';
 import 'package:cabin_booking/model/holiday.dart';
 import 'package:intl/intl.dart';
 
+abstract class _JsonFields {
+  static const holidays = 'h';
+}
+
 class SchoolYear extends DateRange {
   late Set<Holiday> holidays;
 
@@ -22,15 +26,16 @@ class SchoolYear extends DateRange {
 
   SchoolYear.from(Map<String, dynamic> other)
       : holidays = SplayTreeSet.from(
-          (other['holidays'] as List<dynamic>)
+          (other[_JsonFields.holidays] as List<dynamic>)
               .map<Holiday>((holiday) => Holiday.from(holiday)),
         ),
         super.from(other);
 
   @override
   Map<String, dynamic> toJson() => {
         ...super.toJson(),
-        'holidays': holidays.map((holiday) => holiday.toJson()).toList(),
+        _JsonFields.holidays:
+            holidays.map((holiday) => holiday.toJson()).toList(),
       };
 
   Duration get holidaysDuration {