Frontend first draft

frontend/pshared/lib/models/account/account.dart

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+import 'package:pshared/models/account/base.dart';
+
+
+class Account extends AccountBase {
+  final String login;
+
+  const Account({
+    required super.storable,
+    required super.avatarUrl,
+    required this.login,
+    required super.locale,
+    required super.name,
+  });
+
+  factory Account.fromBase(AccountBase accountBase, String login) => Account(
+    storable: accountBase.storable,
+    avatarUrl: accountBase.avatarUrl,
+    locale: accountBase.locale,
+    name: accountBase.name,
+    login: login,
+  );
+
+  @override
+  Account copyWith({
+    String? Function()? avatarUrl,
+    String? name,
+    String? locale,
+  }) {
+    final updatedBase = super.copyWith(
+      avatarUrl: avatarUrl,
+      name: name,
+      locale: locale,
+    );
+    return Account.fromBase(updatedBase, login);
+  }
+}

frontend/pshared/lib/models/account/base.dart

@@ -0,0 +1,35 @@
+import 'package:pshared/models/storable.dart';
+
+
+class AccountBase implements Storable {
+  final Storable storable;
+
+  @override
+  String get id => storable.id;
+  @override
+  DateTime get createdAt => storable.createdAt;
+  @override
+  DateTime get updatedAt => storable.updatedAt;
+
+  final String? avatarUrl;
+  final String name;
+  final String locale;
+
+  const AccountBase({
+    required this.storable,
+    required this.name,
+    required this.locale,
+    required this.avatarUrl,
+  });
+
+   AccountBase copyWith({
+    String? Function()? avatarUrl,
+    String? name,
+    String? locale,
+  }) => AccountBase(
+    storable: storable,
+    avatarUrl: avatarUrl != null ? avatarUrl() : this.avatarUrl,
+    locale: locale ?? this.locale,
+    name: name ?? this.name,
+  );
+}

frontend/pshared/lib/models/organization/description.dart

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+class OrganizationDescription {
+  final String? logoUrl;
+
+  const OrganizationDescription({
+    this.logoUrl,
+  });
+}

frontend/pshared/lib/models/organization/employee.dart

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+import 'package:pshared/models/account/account.dart';
+
+
+typedef Employee = Account;

frontend/pshared/lib/models/organization/organization.dart

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+import 'package:pshared/models/storable.dart';
+
+
+class Organization implements Storable {
+  final Storable storable;
+
+  @override
+  String get id => storable.id;
+  @override
+  DateTime get createdAt => storable.createdAt;
+  @override
+  DateTime get updatedAt => storable.updatedAt;
+
+  final String timeZone;
+  final String? logoUrl;
+
+  const Organization({
+    required this.storable,
+    required this.timeZone,
+    this.logoUrl,
+  });
+
+
+  Organization copyWith({
+    String? name,
+    String? Function()? description,
+    String? timeZone,
+    String? Function()? logoUrl,
+  }) => Organization(
+    storable: storable, // Same Storable, same id
+    timeZone: timeZone ?? this.timeZone,
+    logoUrl: logoUrl != null ? logoUrl() : this.logoUrl,
+  );
+}

frontend/pshared/lib/models/payment/methods/card.dart

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+import 'package:pshared/models/payment/methods/data.dart';
+import 'package:pshared/models/payment/type.dart';
+
+
+class CardPaymentMethod extends PaymentMethodData {
+  @override
+  final PaymentType type = PaymentType.card;
+
+  final String pan;
+  final String firstName;
+  final String lastName;
+
+  CardPaymentMethod({
+    required this.pan,
+    required this.firstName,
+    required this.lastName,
+  });
+}

frontend/pshared/lib/models/payment/methods/data.dart

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+import 'package:pshared/models/payment/type.dart';
+
+
+abstract class PaymentMethodData {
+  PaymentType get type;
+}

frontend/pshared/lib/models/payment/methods/iban.dart

@@ -0,0 +1,20 @@
+import 'package:pshared/models/payment/methods/data.dart';
+import 'package:pshared/models/payment/type.dart';
+
+
+class IbanPaymentMethod extends PaymentMethodData {
+  @override
+  final PaymentType type = PaymentType.iban;
+
+  final String iban;             // e.g. DE89 3704 0044 0532 0130 00
+  final String accountHolder;   // Full name of the recipient
+  final String? bic;            // Optional: for cross-border transfers
+  final String? bankName;       // Optional: for UI clarity
+
+  IbanPaymentMethod({
+    required this.iban,
+    required this.accountHolder,
+    this.bic,
+    this.bankName,
+  });
+}

frontend/pshared/lib/models/payment/methods/russian_bank.dart

@@ -0,0 +1,26 @@
+import 'package:pshared/models/payment/methods/data.dart';
+import 'package:pshared/models/payment/type.dart';
+
+
+class RussianBankAccountPaymentMethod extends PaymentMethodData {
+  @override
+  final PaymentType type = PaymentType.bankAccount;
+
+  final String recipientName; 
+  final String inn;           
+  final String kpp;          
+  final String bankName;      
+  final String bik;          
+  final String accountNumber;
+  final String correspondentAccount;
+
+  RussianBankAccountPaymentMethod({
+    required this.recipientName,
+    required this.inn,
+    required this.kpp,
+    required this.bankName,
+    required this.bik,
+    required this.accountNumber,
+    required this.correspondentAccount,
+  });
+}

frontend/pshared/lib/models/payment/methods/type.dart

@@ -0,0 +1,21 @@
+import 'package:pshared/models/payment/type.dart';
+
+
+class PaymentMethod {
+  PaymentMethod({
+    required this.id,
+    required this.label,
+    required this.details,
+    required this.type,
+    this.isEnabled = true,
+    this.isMain = false,
+  });
+
+  final String id;
+  final String label;
+  final String details;
+  final PaymentType type;
+
+  bool isEnabled;
+  bool isMain;
+}

frontend/pshared/lib/models/payment/methods/wallet.dart

@@ -0,0 +1,12 @@
+import 'package:pshared/models/payment/methods/data.dart';
+import 'package:pshared/models/payment/type.dart';
+
+
+class WalletPaymentMethod extends PaymentMethodData {
+  @override
+  final PaymentType type = PaymentType.wallet;
+
+  final String walletId;
+
+  WalletPaymentMethod({required this.walletId});
+}

frontend/pshared/lib/models/payment/operation.dart

@@ -0,0 +1,30 @@
+import 'package:pshared/models/payment/status.dart';
+
+
+class OperationItem {
+  final OperationStatus status;
+  final String? fileName;
+  final double amount;
+  final String currency;
+  final double toAmount;
+  final String toCurrency;
+  final String payId;
+  final String? cardNumber;
+  final String name;
+  final DateTime date;
+  final String comment;
+
+  OperationItem({
+    required this.status,
+    this.fileName,
+    required this.amount,
+    required this.currency,
+    required this.toAmount,
+    required this.toCurrency,
+    required this.payId,
+    this.cardNumber,
+    required this.name,
+    required this.date,
+    required this.comment,
+  });
+}

frontend/pshared/lib/models/payment/status.dart

@@ -0,0 +1,25 @@
+import 'package:flutter/widgets.dart';
+import 'package:pshared/generated/i18n/ps_localizations.dart';
+
+enum OperationStatus {
+  processing,
+  success,
+  error,
+}
+
+
+extension OperationStatusX on OperationStatus {
+  /// Returns the localized string for this status,
+  /// e.g. “Processing”, “Success”, “Error”.
+  String localized(BuildContext context) {
+    final loc = PSLocalizations.of(context)!;
+    switch (this) {
+      case OperationStatus.processing:
+        return loc.operationStatusProcessing;
+      case OperationStatus.success:
+        return loc.operationStatusSuccess;
+      case OperationStatus.error:
+        return loc.operationStatusError;
+    }
+  }
+}

frontend/pshared/lib/models/payment/type.dart

@@ -0,0 +1,6 @@
+enum PaymentType { 
+  bankAccount, 
+  iban, 
+  wallet, 
+  card,
+}

frontend/pshared/lib/models/payment/upload_history_item.dart

@@ -0,0 +1,11 @@
+class UploadHistoryItem {
+  final String name;
+  final String status;
+  final String time;
+
+  UploadHistoryItem({
+    required this.name,
+    required this.status,
+    required this.time,
+  });
+}

frontend/pshared/lib/models/permission_bound.dart

@@ -0,0 +1,22 @@
+import 'package:pshared/config/constants.dart';
+
+
+abstract class PermissionBound {
+  String get permissionRef;
+  String get organizationRef;
+}
+
+class _PermissionBoundImp implements PermissionBound {
+  @override
+  final String permissionRef;
+  @override
+  final String organizationRef;
+
+  const _PermissionBoundImp({
+    required this.permissionRef,
+    required this.organizationRef,
+  });
+}
+
+PermissionBound newPermissionBound({ required String organizationRef, String? permissionRef}) => 
+  _PermissionBoundImp(permissionRef: permissionRef ?? Constants.nilObjectRef, organizationRef: organizationRef);

frontend/pshared/lib/models/permission_bound_storable.dart

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+import 'package:pshared/models/permission_bound.dart';
+import 'package:pshared/models/storable.dart';
+
+
+abstract class PermissionBoundStorable implements PermissionBound, Storable {
+}

frontend/pshared/lib/models/permissions/access.dart

@@ -0,0 +1,13 @@
+import 'package:pshared/models/permissions/data/permissions.dart';
+import 'package:pshared/models/permissions/descriptions/permissions.dart';
+
+
+class UserAccess {
+  final PermissionsDescription descriptions;
+  final PermissionsData permissions;
+
+  const UserAccess({
+    required this.descriptions,
+    required this.permissions,
+  });
+}

frontend/pshared/lib/models/permissions/action.dart

@@ -0,0 +1,15 @@
+enum Action {
+  create,
+  read,
+  update,
+  delete,
+}
+
+extension ActionExtension on Action {
+  String toShortString() => toString().split('.').last;
+
+  static Action fromString(String value) => Action.values.firstWhere(
+    (e) => e.toShortString() == value,
+    orElse: () => throw ArgumentError('Invalid action: $value'),
+  );
+}

frontend/pshared/lib/models/permissions/action_effect.dart

@@ -0,0 +1,13 @@
+import 'package:pshared/models/permissions/action.dart';
+import 'package:pshared/models/permissions/effect.dart';
+
+
+class ActionEffect {
+  final Action action; // The action allowed or denied
+  final Effect effect; // The effect of the policy ("allow" or "deny")
+
+  const ActionEffect({
+    required this.action,
+    required this.effect,
+  });
+}

frontend/pshared/lib/models/permissions/data/permission.dart

@@ -0,0 +1,12 @@
+import 'package:pshared/models/permissions/data/policy.dart';
+
+
+class Permission {
+  final Policy policy;
+  final String accountRef;
+
+  const Permission({
+    required this.policy,
+    required this.accountRef,
+  });
+}

frontend/pshared/lib/models/permissions/data/permissions.dart

@@ -0,0 +1,16 @@
+import 'package:pshared/models/permissions/data/permission.dart';
+import 'package:pshared/models/permissions/data/policy.dart';
+import 'package:pshared/models/permissions/data/role.dart';
+
+
+class PermissionsData {
+  final List<Role> roles;
+  final List<Policy> policies;
+  final List<Permission> permissions;
+
+  const PermissionsData({
+    required this.roles,
+    required this.policies,
+    required this.permissions,
+  });
+}

frontend/pshared/lib/models/permissions/data/policy.dart

@@ -0,0 +1,18 @@
+import 'package:pshared/models/permissions/action_effect.dart';
+
+
+class Policy {
+  final String roleDescriptionRef;
+  final String organizationRef;
+  final String descriptionRef;
+  final String? objectRef;
+  final ActionEffect effect;
+
+  const Policy({
+    required this.roleDescriptionRef,
+    required this.organizationRef,
+    required this.descriptionRef,
+    required this.objectRef,
+    required this.effect,
+  });
+}

frontend/pshared/lib/models/permissions/data/role.dart

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+class Role {
+  final String accountRef;
+  final String organizationRef;
+  final String descriptionRef;
+
+  const Role({
+    required this.accountRef,
+    required this.descriptionRef,
+    required this.organizationRef,
+  });
+}

frontend/pshared/lib/models/permissions/descriptions/permissions.dart

@@ -0,0 +1,13 @@
+import 'package:pshared/models/permissions/descriptions/policy.dart';
+import 'package:pshared/models/permissions/descriptions/role.dart';
+
+
+class PermissionsDescription {
+  final List<RoleDescription> roles;
+  final List<PolicyDescription> policies;
+
+  const PermissionsDescription({
+    required this.roles,
+    required this.policies,
+  });
+}

frontend/pshared/lib/models/permissions/descriptions/policy.dart

@@ -0,0 +1,22 @@
+import 'package:pshared/models/resources.dart';
+import 'package:pshared/models/storable.dart';
+
+
+class PolicyDescription implements Storable {
+  final Storable storable;
+  final List<ResourceType>? resourceTypes;
+  final String? organizationRef;
+
+  @override
+  String get id => storable.id;
+  @override
+  DateTime get createdAt => storable.createdAt;
+  @override
+  DateTime get updatedAt => storable.updatedAt;
+
+  const PolicyDescription({
+    required this.storable,
+    required this.resourceTypes,
+    required this.organizationRef,
+  });
+}

frontend/pshared/lib/models/permissions/descriptions/role.dart

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+import 'package:pshared/models/storable.dart';
+
+
+class RoleDescription implements Storable {
+  final Storable storable;
+
+  @override
+  String get id => storable.id;
+  @override
+  DateTime get createdAt => storable.createdAt;
+  @override
+  DateTime get updatedAt => storable.updatedAt;
+  
+  final String organizationRef;
+
+  const RoleDescription({
+    required this.storable,
+    required this.organizationRef,
+  });
+
+  factory RoleDescription.build({
+    required String organizationRef,
+  }) => RoleDescription(
+      storable: newStorable(), 
+      organizationRef: organizationRef
+    );
+}

frontend/pshared/lib/models/permissions/effect.dart

@@ -0,0 +1,13 @@
+enum Effect {
+  allow,
+  deny,
+}
+
+extension EffectExtension on Effect {
+  String toShortString() => toString().split('.').last;
+
+  static Effect fromString(String value) => Effect.values.firstWhere(
+    (e) => e.toShortString() == value,
+    orElse: () => throw ArgumentError('Invalid effect: $value'),
+  );
+}

frontend/pshared/lib/models/recipient/filter.dart

@@ -0,0 +1 @@
+enum RecipientFilter { all, ready, registered, notRegistered }

frontend/pshared/lib/models/recipient/recipient.dart

@@ -0,0 +1,78 @@
+import 'package:pshared/models/payment/methods/card.dart';
+import 'package:pshared/models/payment/methods/iban.dart';
+import 'package:pshared/models/payment/methods/russian_bank.dart';
+import 'package:pshared/models/payment/methods/wallet.dart';
+import 'package:pshared/models/recipient/status.dart';
+import 'package:pshared/models/recipient/type.dart';
+
+
+class Recipient {
+  final String? avatarUrl; // network URL / local asset
+  final String name;
+  final String email;
+  final RecipientStatus status;
+  final RecipientType type;
+  final CardPaymentMethod? card;
+  final IbanPaymentMethod? iban;
+  final RussianBankAccountPaymentMethod? bank;
+  final WalletPaymentMethod? wallet;
+
+  const Recipient({
+    this.avatarUrl,
+    required this.name,
+    required this.email,
+    required this.status,
+    required this.type,
+    this.card,
+    this.iban,
+    this.bank,
+    this.wallet,
+  });
+
+  /// Convenience factory for quickly creating mock recipients.
+  factory Recipient.mock({
+    required String name,
+    required String email,
+    required RecipientStatus status,
+    required RecipientType type,
+    CardPaymentMethod? card,
+    IbanPaymentMethod? iban,
+    RussianBankAccountPaymentMethod? bank,
+    WalletPaymentMethod? wallet,
+  }) =>
+      Recipient(
+        avatarUrl: null,
+        name: name,
+        email: email,
+        status: status,
+        type: type,
+        card: card,
+        iban: iban,
+        bank: bank,
+        wallet: wallet,
+      );
+
+  bool matchesQuery(String q) {
+    final searchable = [
+      name,
+      email,
+      card?.pan,
+      card?.firstName,
+      card?.lastName,
+      iban?.iban,
+      iban?.accountHolder,
+      iban?.bic,
+      iban?.bankName,
+      bank?.accountNumber,
+      bank?.recipientName,
+      bank?.inn,
+      bank?.kpp,
+      bank?.bankName,
+      bank?.bik,
+      bank?.correspondentAccount,
+      wallet?.walletId,
+    ];
+
+    return searchable.any((field) => field?.toLowerCase().contains(q) ?? false);
+  }
+}

frontend/pshared/lib/models/recipient/status.dart

@@ -0,0 +1,22 @@
+import 'package:flutter/widgets.dart';
+
+import 'package:pshared/generated/i18n/ps_localizations.dart';
+
+
+/// Possible payout readiness states.
+enum RecipientStatus { ready, registered, notRegistered }
+
+extension RecipientStatusExtension on RecipientStatus {
+  /// Human-readable, **localized** label for display in the UI.
+  String label(BuildContext context) {
+    final l10n = PSLocalizations.of(context)!;
+    switch (this) {
+      case RecipientStatus.ready:
+        return l10n.statusReady;
+      case RecipientStatus.registered:
+        return l10n.statusRegistered;
+      case RecipientStatus.notRegistered:
+        return l10n.statusNotRegistered;
+    }
+  }
+}

frontend/pshared/lib/models/recipient/type.dart

@@ -0,0 +1,15 @@
+import 'package:flutter/widgets.dart';
+
+import 'package:pshared/generated/i18n/ps_localizations.dart';
+
+
+/// Indicates whether you (internal) or the other party (external) manage payout data.
+enum RecipientType { internal, external }
+
+extension RecipientTypeExtension on RecipientType {
+  /// Localized label – no opaque abbreviations.
+  String label(BuildContext context) =>
+      this == RecipientType.internal
+          ? PSLocalizations.of(context)!.typeInternal
+          : PSLocalizations.of(context)!.typeExternal;
+}

frontend/pshared/lib/models/resources.dart

@@ -0,0 +1,107 @@
+import 'package:json_annotation/json_annotation.dart';
+
+/// Represents various resource types (mirroring your Go "Type" constants).
+enum ResourceType {
+  /// Represents user accounts in the system
+  @JsonValue('accounts')
+  accounts,
+
+  /// Represents analytics integration with Amplitude
+  @JsonValue('amplitude')
+  amplitude,
+
+  /// Represents automation workflows
+  @JsonValue('automations')
+  automations,
+
+  /// Tracks changes made to resources
+  @JsonValue('changes')
+  changes,
+
+  /// Represents client information
+  @JsonValue('clients')
+  clients,
+
+  /// Represents comments on tasks or other resources
+  @JsonValue('comments')
+  comments,
+
+  /// Represents invitations sent to users
+  @JsonValue('invitations')
+  invitations,
+
+  /// Represents invoices
+  @JsonValue('invoices')
+  invoices,
+
+  /// Represents logos for organizations or projects
+  @JsonValue('logo')
+  logo,
+
+  /// Represents notifications sent to users
+  @JsonValue('notifications')
+  notifications,
+
+  /// Represents organizations in the system
+  @JsonValue('organizations')
+  organizations,
+
+  /// Represents permissions service
+  @JsonValue('permissions')
+  permissions,
+
+  /// Represents access control policies
+  @JsonValue('policies')
+  policies,
+
+  /// Represents task or project priorities
+  @JsonValue('priorities')
+  priorities,
+
+  /// Represents priority groups
+  @JsonValue('priority_groups')
+  priorityGroups,
+
+  /// Represents projects managed in the system
+  @JsonValue('projects')
+  projects,
+
+  @JsonValue('properties')
+  properties,
+
+  /// Represents reactions
+  @JsonValue('reactions')
+  reactions,
+
+  /// Represents refresh tokens for authentication
+  @JsonValue('refresh_tokens')
+  refreshTokens,
+
+  /// Represents roles in access control
+  @JsonValue('roles')
+  roles,
+
+  /// Represents statuses of tasks or projects
+  @JsonValue('statuses')
+  statuses,
+
+  /// Represents steps in workflows or processes
+  @JsonValue('steps')
+  steps,
+
+  /// Represents tasks managed in the system
+  @JsonValue('tasks')
+  tasks,
+
+  /// Represents teams managed in the system
+  @JsonValue('teams')
+  teams,
+
+  /// Represents workflows for tasks or projects
+  @JsonValue('workflows')
+  workflows,
+
+  /// Represents workspaces containing projects and teams
+  @JsonValue('workspaces')
+  workspaces;
+}

frontend/pshared/lib/models/settings/localizations.dart

@@ -0,0 +1,77 @@
+import 'package:flutter/material.dart';
+
+
+typedef LangLocalization = Map<String, String>;
+
+String _translation(LangLocalization loc, String key) {
+  return loc[key] ?? '';
+}
+
+typedef Localizations = Map<String, LangLocalization>;
+
+typedef Localizer = String Function(BuildContext);
+
+class Localization {
+
+  static const String keyHint = 'hint';
+  static const String keyLink = 'link';
+  static const String keyName = 'name';
+  static const String keyError = 'error';
+  static const String keyAddress = 'address';
+  static const String keyDetails = 'details';
+  static const String keyRoute = 'route';
+  static const String keyLocationName = 'location_name';
+
+  static String _localizeImp(Localizations localizations, String locale, String Function(LangLocalization) functor) {
+    final localization = localizations[locale];
+    if (localization != null) {
+      return functor(localization);
+    }
+    return '';
+  }
+
+  static String _localize(Localizations localizations, String locale, String Function(LangLocalization) functor, {String? fallback}) {
+    final res = _localizeImp(localizations, locale, functor);
+    return res.isNotEmpty ? res : (fallback ?? '');
+  }
+
+  static bool localizationExists(Localizations loc, String locale) {
+    return loc.containsKey(locale);
+  }
+
+  static String hint(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyHint), fallback: fallback);
+  }
+
+  static String link(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyLink), fallback: fallback);
+  }
+
+  static String name(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyName), fallback: fallback);
+  }
+
+  static String error(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyError), fallback: fallback);
+  }
+
+  static String address(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyAddress), fallback: fallback);
+  }
+
+  static String details(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyDetails), fallback: fallback);
+  }
+
+  static String route(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyRoute), fallback: fallback);
+  }
+
+  static String locationName(Localizations loc, String locale, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, keyLocationName), fallback: fallback);
+  }
+
+  static String translate(Localizations loc, String locale, String key, {String? fallback}) {
+    return _localize(loc, locale, (localization) => _translation(localization, key), fallback: fallback);
+  }
+}

frontend/pshared/lib/models/settings/time_validity.dart

@@ -0,0 +1,27 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'time_validity.g.dart';
+
+
+@JsonSerializable()
+class TimeValidity {
+  final DateTime? start;
+  final DateTime? expiry;
+
+  const TimeValidity({this.start, this.expiry});
+
+  bool get isExpired => expiry?.isBefore(DateTime.now()) ?? false;
+  bool get isNotStarted => start?.isAfter(DateTime.now()) ?? false;
+  bool get isActive => (!isNotStarted) && (!isExpired);
+
+  TimeValidity copyWith({
+    DateTime? Function()? start, 
+    DateTime? Function()? expiry, 
+  }) => TimeValidity(
+    start: start == null ? this.start : start(),
+    expiry: expiry == null ? this.expiry : expiry(),
+  );
+
+  factory TimeValidity.fromJson(Map<String, dynamic> json) => _$TimeValidityFromJson(json);
+  Map<String, dynamic> toJson() => _$TimeValidityToJson(this);
+}

frontend/pshared/lib/models/storable.dart

@@ -0,0 +1,30 @@
+import 'package:pshared/config/constants.dart';
+
+
+abstract class Storable {
+  String get id;
+  DateTime get createdAt;
+  DateTime get  updatedAt;
+}
+
+class _StorableImp implements Storable {
+  @override
+  final String id;
+  @override
+  final DateTime createdAt;
+  @override
+  final DateTime updatedAt;
+
+  const _StorableImp({
+    required this.id,
+    required this.createdAt,
+    required this.updatedAt,
+  });
+
+}
+
+Storable newStorable({String? id, DateTime? createdAt, DateTime? updatedAt}) => _StorableImp(
+  id: id ?? Constants.nilObjectRef, 
+  createdAt: createdAt ?? DateTime.now().toUtc(), 
+  updatedAt: updatedAt ?? DateTime.now().toUtc(),
+);