Submit customer identity proofs and show reviewed limits

frontend/packages/sxchnge_kyc/lib/src/mappers/backend.dart

@@ -0,0 +1,51 @@
+import '../models/identity.dart';
+import '../models/limits.dart';
+import '../transport/backend.dart';
+
+abstract final class VerificationMapper {
+  static Limits limits(PolicyDTO dto) => Limits(
+    tier: AccountTier.values.byName(dto.tier),
+    rows: const [],
+    simulated: false,
+    profileRef: dto.profileRef,
+    entries: dto.entries
+        .map(
+          (v) => PolicyLimit(
+            operation: v.operation,
+            period: v.period,
+            currency: v.currency,
+            cap: v.cap,
+            remaining: v.remaining,
+            used: v.used,
+            reserved: v.reserved,
+          ),
+        )
+        .toList(),
+  );
+  static Identity fromDTO(VerificationDTO dto) => Identity(
+    upgradePending: dto.upgradePending,
+    status: IdentityStatus.values.byName(dto.status),
+    reason: dto.reason == null || dto.reason!.isEmpty
+        ? null
+        : ReviewReason.values.byName(dto.reason!),
+    submissionId: dto.id,
+    profile: IdentityProfile(
+      fullName: dto.profile.fullName,
+      dateOfBirth: dto.profile.dateOfBirth,
+      residenceCountry: dto.profile.residenceCountry,
+    ),
+  );
+  static ProfileDTO profile(IdentityProfile value) => ProfileDTO(
+    value.fullName.trim(),
+    value.dateOfBirth,
+    value.residenceCountry,
+  );
+  static KycException failure(int status) => KycException(switch (status) {
+    400 || 413 || 415 || 422 => KycError.format,
+    401 => KycError.sessionExpired,
+    403 => KycError.permission,
+    409 => KycError.conflict,
+    429 => KycError.rateLimited,
+    _ => KycError.unavailable,
+  });
+}

frontend/packages/sxchnge_kyc/lib/src/models/identity.dart

@@ -36,16 +36,40 @@ class Identity {
     this.reason,
     this.submissionId,
     this.simulated = false,
+    this.profile = const IdentityProfile(),
+    this.upgradePending = false,
   });
   final IdentityStatus status;
   final ReviewReason? reason;
   final String? submissionId;
   final bool simulated;
+  final IdentityProfile profile;
+  final bool upgradePending;
   bool get canSubmit =>
       status == IdentityStatus.unverified ||
       status == IdentityStatus.changesRequested;
 }
 
+/// Customer assertions awaiting human review, distinct from a verified identity.
+class IdentityProfile {
+  const IdentityProfile({
+    this.fullName = '',
+    this.dateOfBirth = '',
+    this.residenceCountry = '',
+  });
+  final String fullName, dateOfBirth, residenceCountry;
+  bool get isComplete {
+    final date = DateTime.tryParse(dateOfBirth);
+    return fullName.trim().isNotEmpty &&
+        fullName.length <= 200 &&
+        RegExp(r'^\d{4}-\d{2}-\d{2}$').hasMatch(dateOfBirth) &&
+        date != null &&
+        date.toIso8601String().startsWith(dateOfBirth) &&
+        date.isBefore(DateTime.now()) &&
+        RegExp(r'^[A-Z]{2}$').hasMatch(residenceCountry);
+  }
+}
+
 /// Ephemeral image data only. Never serialize this model into storage or telemetry.
 class Photo {
   Photo(Uint8List bytes)

frontend/packages/sxchnge_kyc/lib/src/models/limits.dart

@@ -33,8 +33,28 @@ class Limits {
     required this.tier,
     required List<VisibleLimit> rows,
     required this.simulated,
-  }) : rows = List.unmodifiable(rows);
+    this.profileRef,
+    List<PolicyLimit> entries = const [],
+  }) : rows = List.unmodifiable(rows),
+       entries = List.unmodifiable(entries);
   final AccountTier tier;
   final List<VisibleLimit> rows;
   final bool simulated;
+  final String? profileRef;
+  final List<PolicyLimit> entries;
+}
+
+/// Authoritative policy amounts in major units. Keep decimal strings intact,
+/// including currencies whose precision differs from fiat's common two digits.
+class PolicyLimit {
+  const PolicyLimit({
+    required this.operation,
+    required this.period,
+    required this.currency,
+    required this.cap,
+    required this.remaining,
+    required this.used,
+    required this.reserved,
+  });
+  final String operation, period, currency, cap, remaining, used, reserved;
 }

frontend/packages/sxchnge_kyc/lib/src/providers/identity.dart

@@ -22,6 +22,7 @@ class IdentityProvider extends ChangeNotifier {
   Identity? record;
   Photo? passport;
   Photo? selfie;
+  IdentityProfile profile = const IdentityProfile();
   KycError? error;
   PhotoKind? photoError;
   bool busy = false;
@@ -31,11 +32,13 @@ class IdentityProvider extends ChangeNotifier {
   int step = 0;
   bool _disposed = false;
   String? _key;
-  bool get hasDraft => passport != null || selfie != null;
+  bool _profileTouched = false;
+  bool get hasDraft => passport != null || selfie != null || _profileTouched;
   bool get canSubmit =>
       !busy &&
       !stale &&
       confirmed &&
+      profile.isComplete &&
       passport != null &&
       selfie != null &&
       (record?.canSubmit ?? false);
@@ -57,6 +60,7 @@ class IdentityProvider extends ChangeNotifier {
       final result = await service.fetch();
       if (_disposed) return;
       record = result;
+      if (!editing) profile = result.profile;
       stale = false;
       await onStatusChanged?.call();
       if (_disposed) return;
@@ -144,6 +148,7 @@ class IdentityProvider extends ChangeNotifier {
 
   void next() {
     if (busy ||
+        (step == 0 && !profile.isComplete) ||
         (step == 0 && passport == null) ||
         (step == 1 && selfie == null))
       return;
@@ -152,6 +157,15 @@ class IdentityProvider extends ChangeNotifier {
     _notify();
   }
 
+  void updateProfile(IdentityProfile value) {
+    if (busy || !editing) return;
+    profile = value;
+    _profileTouched = true;
+    confirmed = false;
+    _key = null;
+    _notify();
+  }
+
   void confirm(bool value) {
     if (!busy) {
       confirmed = value;
@@ -172,6 +186,7 @@ class IdentityProvider extends ChangeNotifier {
     final op = _begin(JourneyStep.kycSubmission);
     try {
       final result = await service.submit(
+        profile: profile,
         passport: passport!,
         selfie: selfie!,
         idempotencyKey: _key!,
@@ -217,6 +232,8 @@ class IdentityProvider extends ChangeNotifier {
   }
 
   void _clear() {
+    _profileTouched = false;
+    profile = const IdentityProfile();
     passport = null;
     selfie = null;
     confirmed = false;

frontend/packages/sxchnge_kyc/lib/src/providers/onboarding.dart

@@ -0,0 +1,23 @@
+import '../models/identity.dart';
+import '../services/contracts.dart';
+
+/// Offers optional verification once per customer in this app session. Identity
+/// dependency failures must never prevent an already authenticated basic login.
+class IdentityOnboardingProvider {
+  IdentityOnboardingProvider(this.service);
+  final IdentityService service;
+  final _offered = <String>{};
+  Future<bool> offer(String customer) async {
+    if (customer.isEmpty || service.isSimulated || !_offered.add(customer))
+      return false;
+    try {
+      final identity = await service.fetch().timeout(
+        const Duration(seconds: 3),
+      );
+      return identity.status == IdentityStatus.unverified ||
+          identity.status == IdentityStatus.changesRequested;
+    } catch (_) {
+      return false;
+    }
+  }
+}

frontend/packages/sxchnge_kyc/lib/src/services/backend.dart

@@ -0,0 +1,130 @@
+import 'dart:convert';
+
+import 'package:flutter/foundation.dart';
+
+import 'package:http/http.dart' as http;
+
+import '../mappers/backend.dart';
+import '../models/identity.dart';
+import '../models/limits.dart';
+import '../transport/backend.dart';
+import 'contracts.dart';
+import 'http/client.dart';
+
+/// Credentials are read for each operation, so a replaced session cannot leave
+/// documents attached to a previously authenticated customer.
+class BackendIdentityService implements IdentityService {
+  BackendIdentityService({
+    required this.baseUri,
+    required this.accessToken,
+    http.Client? client,
+  }) : _client = client ?? createClient() {
+    if (!baseUri.hasAuthority ||
+        baseUri.hasQuery ||
+        baseUri.hasFragment ||
+        baseUri.userInfo.isNotEmpty ||
+        (baseUri.scheme != 'https' &&
+            !(baseUri.scheme == 'http' &&
+                ['localhost', '127.0.0.1'].contains(baseUri.host))))
+      throw ArgumentError('Valid identity API URL required');
+  }
+  final Uri baseUri;
+  final String? Function() accessToken;
+  final http.Client _client;
+  @override
+  bool get isSimulated => false;
+  Uri get _uri => baseUri.replace(
+    path: '${baseUri.path.replaceFirst(RegExp(r"/$"), "")}/accounts/identity',
+  );
+
+  Future<String> _send(http.BaseRequest request) async {
+    final token = accessToken();
+    if (token == null) throw const KycException(KycError.sessionExpired);
+    request.followRedirects = false;
+    request.headers.addAll({
+      'Authorization': 'Bearer $token',
+      if (kIsWeb) 'X-CSRF-Protection': '1',
+    });
+    try {
+      final response = await _client
+          .send(request)
+          .then(http.Response.fromStream)
+          .timeout(const Duration(seconds: 60));
+      if (token != accessToken())
+        throw const KycException(KycError.sessionExpired);
+      if (response.statusCode < 200 || response.statusCode >= 300)
+        throw VerificationMapper.failure(response.statusCode);
+      return response.body;
+    } on KycException {
+      rethrow;
+    } catch (_) {
+      throw const KycException(KycError.unavailable);
+    }
+  }
+
+  Future<T> _mapped<T>(Future<String> response, T Function(String) map) async {
+    try {
+      return map(await response);
+    } on KycException {
+      rethrow;
+    } catch (_) {
+      throw const KycException(KycError.unavailable);
+    }
+  }
+
+  @override
+  Future<Identity> fetch() => _mapped(
+    _send(http.Request('GET', _uri)),
+    (body) => VerificationMapper.fromDTO(VerificationDTO.decode(body)),
+  );
+  Future<Limits> fetchLimits() => _mapped(
+    _send(
+      http.Request(
+        'GET',
+        _uri.replace(
+          path: _uri.path.replaceFirst(RegExp(r'/identity$'), '/limits'),
+        ),
+      ),
+    ),
+    (body) => VerificationMapper.limits(PolicyDTO.decode(body)),
+  );
+  @override
+  Future<Identity> submit({
+    required IdentityProfile profile,
+    required Photo passport,
+    required Photo selfie,
+    required String idempotencyKey,
+  }) async {
+    if (!profile.isComplete) throw const KycException(KycError.incomplete);
+    final request = http.MultipartRequest('POST', _uri)
+      ..fields.addAll({
+        'profile': jsonEncode(VerificationMapper.profile(profile).toJson()),
+        'idempotencyKey': idempotencyKey,
+      })
+      ..files.addAll([
+        http.MultipartFile.fromBytes(
+          'document',
+          passport.bytes,
+          filename: 'document',
+        ),
+        http.MultipartFile.fromBytes(
+          'selfie',
+          selfie.bytes,
+          filename: 'selfie',
+        ),
+      ]);
+    return _mapped(
+      _send(request),
+      (body) => VerificationMapper.fromDTO(VerificationDTO.decode(body)),
+    );
+  }
+
+  void close() => _client.close();
+}
+
+class BackendLimitsService implements LimitsService {
+  const BackendLimitsService(this.identity);
+  final BackendIdentityService identity;
+  @override
+  Future<Limits> fetch() => identity.fetchLimits();
+}

frontend/packages/sxchnge_kyc/lib/src/services/contracts.dart

@@ -8,6 +8,7 @@ abstract interface class IdentityService {
   /// Backend adapters must scope the key to the authenticated account and reject
   /// stale/duplicate review transitions. Retrying the same key is idempotent.
   Future<Identity> submit({
+    required IdentityProfile profile,
     required Photo passport,
     required Photo selfie,
     required String idempotencyKey,

frontend/packages/sxchnge_kyc/lib/src/services/dummy.dart

@@ -27,6 +27,7 @@ class DummyIdentityService implements IdentityService {
 
   @override
   Future<Identity> submit({
+    required IdentityProfile profile,
     required Photo passport,
     required Photo selfie,
     required String idempotencyKey,
@@ -35,7 +36,7 @@ class DummyIdentityService implements IdentityService {
     if (_lastKey == idempotencyKey) return IdentityMapper.fromDTO(_record);
     if (!IdentityMapper.fromDTO(_record).canSubmit)
       throw const KycException(KycError.conflict);
-    if (passport.bytes.isEmpty || selfie.bytes.isEmpty)
+    if (!profile.isComplete || passport.bytes.isEmpty || selfie.bytes.isEmpty)
       throw const KycException(KycError.incomplete);
     _lastKey = idempotencyKey;
     _record = IdentityDTO('pending', id: idempotencyKey);

frontend/packages/sxchnge_kyc/lib/src/services/http/browser.dart

@@ -0,0 +1,4 @@
+import 'package:http/browser_client.dart';
+import 'package:http/http.dart' as http;
+
+http.Client createClient() => BrowserClient()..withCredentials = true;

frontend/packages/sxchnge_kyc/lib/src/services/http/client.dart

@@ -0,0 +1 @@
+export 'native.dart' if (dart.library.js_interop) 'browser.dart';

frontend/packages/sxchnge_kyc/lib/src/services/http/native.dart

@@ -0,0 +1,3 @@
+import 'package:http/http.dart' as http;
+
+http.Client createClient() => http.Client();

frontend/packages/sxchnge_kyc/lib/src/transport/backend.dart

@@ -0,0 +1,74 @@
+import 'dart:convert';
+
+class ProfileDTO {
+  const ProfileDTO(this.fullName, this.dateOfBirth, this.residenceCountry);
+  factory ProfileDTO.fromJson(Map<String, dynamic> data) => ProfileDTO(
+    data['fullName'] as String? ?? '',
+    data['dateOfBirth'] as String? ?? '',
+    data['residenceCountry'] as String? ?? '',
+  );
+  final String fullName, dateOfBirth, residenceCountry;
+  Map<String, String> toJson() => {
+    'fullName': fullName,
+    'dateOfBirth': dateOfBirth,
+    'residenceCountry': residenceCountry,
+  };
+}
+
+class VerificationDTO {
+  const VerificationDTO(
+    this.status,
+    this.reason,
+    this.id,
+    this.profile, {
+    this.upgradePending = false,
+  });
+  factory VerificationDTO.decode(String body) {
+    final envelope = jsonDecode(body) as Map<String, dynamic>;
+    if (envelope['status'] != 'success')
+      throw const FormatException('Unaccepted verification');
+    final data = envelope['data'] as Map<String, dynamic>;
+    return VerificationDTO(
+      data['status'] as String,
+      data['reason'] as String?,
+      data['submissionId'] as String?,
+      ProfileDTO.fromJson(data['profile'] as Map<String, dynamic>),
+      upgradePending: data['upgradePending'] as bool? ?? false,
+    );
+  }
+  final String status;
+  final String? reason, id;
+  final ProfileDTO profile;
+  final bool upgradePending;
+}
+
+class PolicyDTO {
+  const PolicyDTO(this.tier, this.profileRef, this.entries);
+  factory PolicyDTO.decode(String body) {
+    final envelope = jsonDecode(body) as Map<String, dynamic>;
+    if (envelope['status'] != 'success')
+      throw const FormatException('Unaccepted limits');
+    final data = envelope['data'] as Map<String, dynamic>;
+    return PolicyDTO(
+      data['tier'] as String,
+      data['profileRef'] as String,
+      (data['entries'] as List)
+          .map((v) => LimitDTO.fromJson(v as Map<String, dynamic>))
+          .toList(),
+    );
+  }
+  final String tier, profileRef;
+  final List<LimitDTO> entries;
+}
+
+class LimitDTO {
+  LimitDTO.fromJson(Map<String, dynamic> d)
+    : operation = d['operation'] as String,
+      period = d['period'] as String,
+      currency = d['currency'] as String,
+      cap = d['cap'] as String,
+      remaining = d['remaining'] as String,
+      used = d['used'] as String,
+      reserved = d['reserved'] as String;
+  final String operation, period, currency, cap, remaining, used, reserved;
+}

frontend/packages/sxchnge_kyc/lib/src/transport/contracts.dart

@@ -1,7 +1,7 @@
 import '../models/identity.dart';
 import '../models/limits.dart';
 
-// Transport contracts for the stub. Replace with generated backend DTOs later.
+// Transport fixtures for simulated services. Production owns its backend DTOs.
 class IdentityDTO {
   const IdentityDTO(this.status, {this.reason, this.id, this.simulated = true});
   final String status;