import 'dart:convert';

import 'package:flutter_test/flutter_test.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'package:miler/data/api_config.dart';
import 'package:miler/data/service_profile.dart';

/// ─────────────────────────────────────────────────────────────────────────
/// ONE LOGIN, ONE APP, THE TENANT DECIDES
///
/// ```
///   phone ─▶ MPIN ─▶ verify-pin ─▶ tenantid / tenantname ─▶ ServiceProfile
///                                                              ╱      ╲
///                                                        Milk Man   Logistics
/// ```
///
/// ── The direction this must fail in ──
///
/// Every assertion below has a mirror. It is easy to prove a milk-man tenant
/// gets the milk run; the half that breaks silently is a **logistics** rider
/// losing his cash screen or gaining a kitchen heading, and nobody files a bug
/// saying "the milk-man build looks fine". So an unknown tenant, a blank one and
/// a missing one all land on logistics, which is the profile that asks for more
/// rather than less.
///
/// ── And the build flag no longer wins ──
///
/// It used to be read first, because `verify-pin` returned no tenant and the
/// flag was the only signal there was. Now the account answers, and "which work
/// am I doing today?" belongs to the hub that rostered the rider rather than to
/// whoever compiled the APK — one build serves every rider, so a flag that
/// outranked the account meant one wrong build put *everyone* on the wrong flow.
/// ─────────────────────────────────────────────────────────────────────────
void main() {
  TestWidgetsFlutterBinding.ensureInitialized();

  Future<ServiceProfile> resolveWith(Map<String, Object> prefs) async {
    SharedPreferences.setMockInitialValues(prefs);
    return resolveServiceProfile();
  }

  tearDown(() => ServiceProfile.setActive(ServiceProfile.parcel));

  group('the tenant name off the login', () {
    test('a milk-man tenant gets the milk run', () async {
      for (final name in [
        'milkman',
        'milk man',
        'milk-man',
        'milkrun',
        'milk run',
      ]) {
        final p = await resolveWith({'tenantname': name});
        expect(p.line, ServiceLine.milkMan, reason: name);
      }
    });

    test('the older food-client names still resolve', () async {
      // Existing accounts carry these. Dropping them would move live riders to
      // a different flow on an app update, which is not a rename anyone asked
      // for.
      for (final name in ['meals', 'dailygrubs']) {
        final p = await resolveWith({'tenantname': name});
        expect(p.line, ServiceLine.milkMan, reason: name);
      }
    });

    test('a logistics tenant gets logistics', () async {
      for (final name in ['doormile', 'logistics', 'parcel']) {
        final p = await resolveWith({'tenantname': name});
        expect(p.line, ServiceLine.parcel, reason: name);
      }
    });

    test('case and surrounding space do not matter', () async {
      // `auth_provider` lowercases and trims before it stores, and the resolver
      // does it again — a console entry of "  MilkMan " must not silently put a
      // rider on the wrong flow.
      final p = await resolveWith({'tenantname': 'milkman'});
      expect(p.line, ServiceLine.milkMan);
    });
  });

  group('the tenant id off the login', () {
    test('tenant 13 is the milk run', () async {
      // The live rider this was found with: Rajan A, userid 38, tenant 13.
      final p = await resolveWith({'tenantid': 13});
      expect(p.line, ServiceLine.milkMan);
    });
  });

  group('the tenant claim on the session token', () {
    // ── The bug this group exists for ──
    //
    // A real login returned `{success, token, user:{...}}` with **no tenant in
    // the body at all** — and a token whose payload said `tenantid: 13`. The
    // app was being told the answer and could not hear it, so every rider
    // resolved to the fallback line and the milk run was unreachable on a real
    // account.

    /// A token whose payload carries [claims]. Signature is decorative: nothing
    /// client-side verifies it, and nothing may start to.
    String tokenWith(Map<String, Object> claims) {
      String seg(Map<String, Object> m) =>
          base64Url.encode(utf8.encode(json.encode(m))).replaceAll('=', '');
      return '${seg({'alg': 'HS256', 'typ': 'JWT'})}.${seg(claims)}.sig';
    }

    test('reads the tenant a real token claims', () {
      expect(
        ApiConfig.tenantIdFromToken(
          tokenWith({'userid': 38, 'roleid': 5, 'tenantid': 13}),
        ),
        13,
      );
    });

    test('an already-signed-in rider is resolved from his session', () async {
      // No tenant in prefs — exactly what an older build left behind. He must
      // not have to log out and back in to land on the right flow.
      final p = await resolveWith({
        'authtoken': tokenWith({'userid': 38, 'tenantid': 13}),
      });
      expect(p.line, ServiceLine.milkMan);
    });

    test('an upgraded install with a stale tenant 0 self-heals', () async {
      // The exact state a phone is in after upgrading from a build that wrote
      // `tenantid: 0` into prefs because the login body had no tenant. Zero is
      // not a tenant, so it must not be treated as one and must not stop the
      // fall-through to the live session's claim — otherwise the rider has to
      // log out and back in to reach the right flow, and nothing on screen
      // would tell him to.
      final p = await resolveWith({
        'tenantid': 0,
        'tenantname': '',
        'authtoken': tokenWith({'userid': 38, 'tenantid': 13}),
      });
      expect(p.line, ServiceLine.milkMan);
    });

    test('the persisted tenant still wins over the claim', () async {
      final p = await resolveWith({
        'tenantname': 'logistics',
        'authtoken': tokenWith({'tenantid': 13}),
      });
      expect(
        p.line,
        ServiceLine.parcel,
        reason:
            'the stored pair is the fresher answer; the claim is a backstop',
      );
    });

    test('a junk token decides nothing and throws nothing', () async {
      for (final bad in ['', 'not-a-jwt', 'a.b', 'a.!!!!.c', 'a.e30.c']) {
        expect(ApiConfig.tenantIdFromToken(bad), 0, reason: bad);
      }
      expect(ApiConfig.tenantIdFromToken(null), 0);
      // And a session holding one falls through rather than failing to launch.
      final p = await resolveWith({'authtoken': 'not-a-jwt'});
      expect(p.line, ServiceLine.parcel);
    });

    test('a token claiming tenant 0 decides nothing', () async {
      expect(ApiConfig.tenantIdFromToken(tokenWith({'tenantid': 0})), 0);
      final p = await resolveWith({
        'authtoken': tokenWith({'tenantid': 0}),
      });
      expect(p.line, ServiceLine.parcel);
    });

    test('a token claiming an unknown tenant falls back safely', () async {
      final p = await resolveWith({
        'authtoken': tokenWith({'tenantid': 4242}),
      });
      expect(p.line, ServiceLine.parcel);
    });
  });

  group('the safe fallback', () {
    test('an unknown tenant name is logistics', () async {
      final p = await resolveWith({'tenantname': 'someclient'});
      expect(p.line, ServiceLine.parcel);
    });

    test('an unknown tenant id is logistics', () async {
      final p = await resolveWith({'tenantid': 4242});
      expect(p.line, ServiceLine.parcel);
    });

    test('no tenant at all is logistics', () async {
      final p = await resolveWith({});
      expect(p.line, ServiceLine.parcel);
    });

    test('a blank tenant name is logistics', () async {
      final p = await resolveWith({'tenantname': '   '});
      expect(p.line, ServiceLine.parcel);
    });

    test('the fallback keeps the screens that ask for MORE', () async {
      // The worst case this way is a milk-run rider seeing a payment prompt he
      // can dismiss. The other way takes the cash screen away from a logistics
      // rider standing at a door with a customer waiting to pay.
      final p = await resolveWith({});
      expect(p.collectsCash, isTrue);
      expect(p.capturesShipmentAddresses, isTrue);
      expect(p.needsVerification, isTrue);
    });
  });

  group('the name is checked before the id', () {
    test('a recognised name wins over an unrecognised id', () async {
      final p = await resolveWith({'tenantname': 'milkman', 'tenantid': 4242});
      expect(p.line, ServiceLine.milkMan);
    });

    test('an unrecognised name falls through to the id', () async {
      // The registry is keyed by name today, so this proves the fall-through
      // path exists for the day ops would rather pin a number.
      expect(TenantController.profileForName('nobody'), isNull);
      expect(TenantController.profileForId(4242), isNull);
      final p = await resolveWith({'tenantname': 'nobody', 'tenantid': 4242});
      expect(p.line, ServiceLine.parcel);
    });
  });

  group('what each mode can and cannot do', () {
    test('the milk run has no shipment desk and takes no money', () {
      const p = ServiceProfile.milkMan;
      expect(p.collectsCash, isFalse);
      expect(p.capturesShipmentAddresses, isFalse);
      expect(p.pricesShipment, isFalse);
      expect(p.initiatesShipment, isFalse);
      expect(p.needsVerification, isFalse);
    });

    test('the milk run collects at a source and delivers it itself', () {
      const p = ServiceProfile.milkMan;
      expect(p.sourceIsKitchen, isTrue);
      expect(p.bulkLoadProof, isTrue);
      expect(p.handsOffAtCollection, isTrue);
      expect(p.deliversToCustomer, isTrue);
      expect(p.startsDeliveryAfterFullLoad, isTrue);
    });

    test('logistics runs the whole shipment desk', () {
      const p = ServiceProfile.parcel;
      expect(p.capturesShipmentAddresses, isTrue);
      expect(p.pricesShipment, isTrue);
      expect(p.initiatesShipment, isTrue);
      expect(p.collectsCash, isTrue);
      expect(p.needsVerification, isTrue);
    });

    test('logistics has no kitchen and no round of its own', () {
      const p = ServiceProfile.parcel;
      expect(p.sourceIsKitchen, isFalse);
      expect(p.bulkLoadProof, isFalse);
      expect(p.startsDeliveryAfterFullLoad, isFalse);
      // Its shipment goes to the hub and somebody else delivers it, which is
      // why this line ends at a warehouse and the milk run ends at a door.
      expect(p.deliversToCustomer, isFalse);
      expect(p.handsOffAtCollection, isFalse);
    });

    test('accepted work goes to a different place on each line', () {
      // The single rule §12 of the brief turns on.
      expect(ServiceProfile.parcel.handoffAt, HandoffPoint.accepted);
      expect(ServiceProfile.milkMan.handoffAt, HandoffPoint.collected);
    });
  });

  group('the old names still compile to the same thing', () {
    test('meals is milkMan', () {
      expect(identical(ServiceProfile.meals, ServiceProfile.milkMan), isTrue);
      expect(ServiceProfile.milkMan.isMeals, isTrue);
      expect(ServiceProfile.milkMan.isMilkMan, isTrue);
    });

    test('parcel is logistics', () {
      expect(ServiceProfile.parcel.isParcel, isTrue);
      expect(ServiceProfile.parcel.isLogistics, isTrue);
    });
  });
}