second commit

lib/domain/entities/customer.dart

@@ -0,0 +1,123 @@
+import 'package:equatable/equatable.dart';
+
+import '../../core/constants/app_constants.dart';
+
+enum Gender {
+  male('Male'),
+  female('Female'),
+  other('Other'),
+  unspecified('Prefer not to say');
+
+  const Gender(this.label);
+
+  final String label;
+}
+
+/// Loyalty tier, derived from lifetime spend.
+enum MembershipTier {
+  bronze('Bronze', 0, 0.0),
+  silver('Silver', 10000, 0.02),
+  gold('Gold', 50000, 0.05),
+  platinum('Platinum', 150000, 0.08);
+
+  const MembershipTier(this.label, this.threshold, this.discountRate);
+
+  final String label;
+
+  /// Lifetime spend in rupees required to reach this tier.
+  final double threshold;
+
+  /// Automatic bill discount granted to members of this tier.
+  final double discountRate;
+
+  static MembershipTier forSpend(double lifetimeSpend) {
+    return MembershipTier.values.lastWhere(
+      (t) => lifetimeSpend >= t.threshold,
+      orElse: () => MembershipTier.bronze,
+    );
+  }
+
+  MembershipTier? get next {
+    final i = index;
+    return i < MembershipTier.values.length - 1
+        ? MembershipTier.values[i + 1]
+        : null;
+  }
+}
+
+/// A registered shopper. A `null` customer on a sale means walk-in.
+class Customer extends Equatable {
+  const Customer({
+    required this.id,
+    required this.name,
+    required this.mobile,
+    this.email,
+    this.gender = Gender.unspecified,
+    this.dateOfBirth,
+    this.loyaltyPoints = 0,
+    this.lifetimeSpend = 0,
+    this.visitCount = 0,
+    this.createdAt,
+    this.lastVisitAt,
+  });
+
+  final String id;
+  final String name;
+  final String mobile;
+  final String? email;
+  final Gender gender;
+  final DateTime? dateOfBirth;
+  final int loyaltyPoints;
+  final double lifetimeSpend;
+  final int visitCount;
+  final DateTime? createdAt;
+  final DateTime? lastVisitAt;
+
+  MembershipTier get tier => MembershipTier.forSpend(lifetimeSpend);
+
+  /// Cash value of the points currently held.
+  double get redeemableValue =>
+      loyaltyPoints * AppConstants.loyaltyPointValue;
+
+  /// Rupees of additional spend needed to reach the next tier.
+  double? get spendToNextTier {
+    final next = tier.next;
+    if (next == null) return null;
+    return (next.threshold - lifetimeSpend).clamp(0, double.infinity);
+  }
+
+  bool get isBirthdayToday {
+    final dob = dateOfBirth;
+    if (dob == null) return false;
+    final now = DateTime.now();
+    return dob.month == now.month && dob.day == now.day;
+  }
+
+  Customer copyWith({
+    String? name,
+    String? email,
+    Gender? gender,
+    DateTime? dateOfBirth,
+    int? loyaltyPoints,
+    double? lifetimeSpend,
+    int? visitCount,
+    DateTime? lastVisitAt,
+  }) {
+    return Customer(
+      id: id,
+      name: name ?? this.name,
+      mobile: mobile,
+      email: email ?? this.email,
+      gender: gender ?? this.gender,
+      dateOfBirth: dateOfBirth ?? this.dateOfBirth,
+      loyaltyPoints: loyaltyPoints ?? this.loyaltyPoints,
+      lifetimeSpend: lifetimeSpend ?? this.lifetimeSpend,
+      visitCount: visitCount ?? this.visitCount,
+      createdAt: createdAt,
+      lastVisitAt: lastVisitAt ?? this.lastVisitAt,
+    );
+  }
+
+  @override
+  List<Object?> get props => [id, name, mobile, loyaltyPoints, lifetimeSpend];
+}