import 'dart:convert';

import 'package:flutter_test/flutter_test.dart';
import 'package:http/http.dart' as http;
import 'package:http/testing.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:srs_app/core/api.dart';
import 'package:srs_app/core/http_api.dart';

const _user = {
  'id': 7,
  'username': 'kzk.staff',
  'phone': '919847012345',
  'isAdmin': false,
  'active': true,
  'shopIds': [1, 2],
};

const _shop = {'id': 1, 'code': 'KZK', 'name': 'Kozhikode', 'active': true};

const _order = {
  'id': 11,
  'shop': _shop,
  'drawDate': '2026-10-16',
  'createdAt': '2026-10-16T05:30:00Z',
  'edited': true,
  'isPhoto': false,
  'rawText': '1234-2',
  'lines': [
    {
      'ending': '1234',
      'qty': 2,
      'hits': [
        {'tier': 5, 'amount': 1000},
        {'tier': 8, 'amount': 100},
      ],
    },
    {'ending': '5678', 'qty': 1, 'hits': <Object>[]},
  ],
};

http.Response _json(Object body, [int status = 200]) => http.Response(
  jsonEncode(body),
  status,
  headers: {'content-type': 'application/json'},
);

Future<(HttpApi, List<http.Request>, SharedPreferences)> _api(
  http.Response Function(http.Request) reply, {
  Map<String, Object> prefs = const {},
}) async {
  SharedPreferences.setMockInitialValues(prefs);
  final store = await SharedPreferences.getInstance();
  final seen = <http.Request>[];
  final api = HttpApi(
    baseUrl: 'https://srs.test/',
    prefs: store,
    client: MockClient((r) async {
      seen.add(r);
      return reply(r);
    }),
  );
  return (api, seen, store);
}

void main() {
  group('signing in', () {
    test('keeps the token and sends it on later calls', () async {
      final (api, seen, store) = await _api(
        (r) => r.url.path == '/api/auth/login'
            ? _json({'token': 'abc', 'user': _user})
            : _json({'date': '2026-10-16'}),
      );
      final u = await api.login(' kzk.staff ', 'secret-pass');
      expect(u.username, 'kzk.staff');
      expect(u.shopIds, [1, 2]);
      expect(jsonDecode(seen.single.body), {
        'username': 'kzk.staff',
        'password': 'secret-pass',
      });
      expect(seen.single.headers['authorization'], isNull);
      expect(store.getString('token'), 'abc');

      expect(await api.latestDrawDate(), DateTime(2026, 10, 16));
      expect(seen.last.url.toString(), 'https://srs.test/api/draws/latest');
      expect(seen.last.headers['authorization'], 'Bearer abc');
    });

    test('shows the server message for a wrong password', () async {
      final (api, _, store) = await _api(
        (_) => _json({
          'error': 'invalid_credentials',
          'message': 'Incorrect username or password.',
        }, 401),
      );
      await expectLater(
        api.login('a', 'b'),
        throwsA(
          isA<ApiException>().having(
            (e) => e.message,
            'message',
            'Incorrect username or password.',
          ),
        ),
      );
      expect(store.getString('token'), isNull);
    });

    test('restores the user from a saved token, or none without one', () async {
      final (none, calls, _) = await _api((_) => _json(_user));
      expect(await none.restore(), isNull);
      expect(calls, isEmpty);

      final (api, _, _) = await _api(
        (_) => _json(_user),
        prefs: {'token': 'abc'},
      );
      expect((await api.restore())!.id, 7);
    });

    test('forgets an old token the server no longer accepts', () async {
      final (api, _, store) = await _api(
        (_) => _json({'error': 'unauthorized', 'message': 'Expired.'}, 401),
        prefs: {'token': 'old'},
      );
      expect(await api.restore(), isNull);
      expect(store.getString('token'), isNull);
    });

    test('logout drops the token', () async {
      final (api, _, store) = await _api(
        (_) => _json(_user),
        prefs: {'token': 'abc'},
      );
      api.logout();
      await Future<void>.delayed(Duration.zero);
      expect(store.getString('token'), isNull);
    });
  });

  group('a session that ends', () {
    test('clears the token and tells the app', () async {
      final (api, _, store) = await _api(
        (_) => _json({'error': 'unauthorized', 'message': 'Ended.'}, 401),
        prefs: {'token': 'abc'},
      );
      final ended = expectLater(api.sessionEnded, emits(anything));
      await expectLater(
        api.orders(DateTime(2026, 10, 16)),
        throwsA(isA<ApiException>()),
      );
      await ended;
      expect(store.getString('token'), isNull);
    });
  });

  group('failures', () {
    test('an unreachable server gives a plain message', () async {
      SharedPreferences.setMockInitialValues({});
      final api = HttpApi(
        baseUrl: 'https://srs.test',
        prefs: await SharedPreferences.getInstance(),
        client: MockClient((_) async => throw http.ClientException('down')),
      );
      await expectLater(
        api.activeShops(),
        throwsA(
          isA<ApiException>().having(
            (e) => e.message,
            'message',
            startsWith('Unable to reach the server'),
          ),
        ),
      );
    });

    test('a server error without a message is not shown raw', () async {
      final (api, _, _) = await _api((_) => http.Response('<html>', 502));
      await expectLater(
        api.activeShops(),
        throwsA(
          isA<ApiException>().having(
            (e) => e.message,
            'message',
            'Something went wrong on the server. Try again shortly.',
          ),
        ),
      );
    });
  });

  group('reading', () {
    test(
      'turns an order into models in Indian time with every prize',
      () async {
        final (api, seen, _) = await _api((_) => _json(_order));
        final o = await api.order(11);
        expect(seen.single.url.path, '/api/orders/11');
        expect(o.time, DateTime(2026, 10, 16, 11, 0));
        expect(o.drawDate, DateTime(2026, 10, 16));
        expect(o.edited, isTrue);
        expect(o.lines.first.tierText, '5th + 8th prize');
        expect(o.lines.first.perTicket, 1100);
        expect(o.prize, 2200);
        expect(o.lines.last.wins, isFalse);
      },
    );

    test('reads a day of results, an awaited draw included', () async {
      final (api, seen, _) = await _api(
        (_) => _json({
          'draw': {
            'date': '2026-10-17',
            'scheme': null,
            'code': null,
            'published': false,
            'hasWin': false,
          },
          'shops': [
            {
              'shop': _shop,
              'orders': 2,
              'tickets': 9,
              'winTickets': 0,
              'prize': 0,
            },
          ],
        }),
      );
      final r = await api.results(DateTime(2026, 10, 17));
      expect(seen.single.url.path, '/api/draws/2026-10-17/results');
      expect(r.draw.published, isFalse);
      expect(r.draw.label, 'No result yet');
      expect(r.shops.single.tickets, 9);
    });

    test('asks for a month and a shop day with the right addresses', () async {
      final (api, seen, _) = await _api(
        (r) => r.url.path == '/api/draws'
            ? _json({'days': <Object>[]})
            : _json({
                'shop': _shop,
                'draw': {
                  'date': '2026-10-16',
                  'scheme': 'Suvarna Keralam',
                  'code': 'SK-74',
                  'published': true,
                  'hasWin': true,
                },
                'endings': <Object>[],
                'orders': [_order],
              }),
      );
      await api.month(2026, 3);
      expect(
        seen.last.url.toString(),
        'https://srs.test/api/draws?month=2026-03',
      );
      final d = await api.shopDetail(1, DateTime(2026, 10, 16));
      expect(seen.last.url.path, '/api/shops/1/draws/2026-10-16');
      expect(d.draw.label, 'Suvarna Keralam · SK-74');
      expect(d.orders.single.id, 11);
    });
  });

  group('changing things', () {
    test('sends each edit to the right place', () async {
      final (api, seen, _) = await _api(
        (r) => r.method == 'POST' ? _json(_shop, 201) : http.Response('', 204),
      );
      await api.setLineQty(11, '1234', 5);
      await api.removeLine(11, '1234');
      await api.cancelOrder(11);
      await api.setShopActive(1, false);
      await api.renameShop(1, 'New name');
      await api.setUserShops(7, [1, 2]);
      await api.deleteUser(7);
      final shop = await api.createShop('Kozhikode', 'KZK');

      final calls = [for (final r in seen) '${r.method} ${r.url.path}'];
      expect(calls, [
        'PUT /api/orders/11/lines/1234',
        'DELETE /api/orders/11/lines/1234',
        'DELETE /api/orders/11',
        'PATCH /api/shops/1',
        'PATCH /api/shops/1',
        'PUT /api/users/7/shops',
        'DELETE /api/users/7',
        'POST /api/shops',
      ]);
      expect(jsonDecode(seen[0].body), {'qty': 5});
      expect(jsonDecode(seen[3].body), {'active': false});
      expect(jsonDecode(seen[5].body), {
        'shopIds': [1, 2],
      });
      expect(shop.code, 'KZK');
    });

    test('sends only the user fields that changed', () async {
      final (api, seen, _) = await _api((_) => http.Response('', 204));
      await api.updateUser(7, username: 'new.name');
      await api.updateUser(7, clearPhone: true);
      await api.updateUser(7, active: false, password: 'longenough');
      await api.updateUser(7, sendResults: true);
      expect(jsonDecode(seen[0].body), {'username': 'new.name'});
      expect(jsonDecode(seen[1].body), {'phone': null});
      expect(jsonDecode(seen[2].body), {
        'password': 'longenough',
        'active': false,
      });
      expect(jsonDecode(seen[3].body), {'sendResults': true});
    });

    test(
      'reads the results setting, off when the server leaves it out',
      () async {
        final (api, _, _) = await _api(
          (r) => r.url.path == '/api/users/7'
              ? _json({..._user, 'sendResults': true})
              : _json(_user),
        );
        expect((await api.user(7)).sendResults, isTrue);
        expect((await api.user(8)).sendResults, isFalse);
      },
    );

    test('creates a user with a password and shops', () async {
      final (api, seen, _) = await _api((_) => _json(_user, 201));
      final u = await api.createUser(
        username: 'kzk.staff',
        password: 'longenough',
        shopIds: [1, 2],
      );
      expect(jsonDecode(seen.single.body), {
        'username': 'kzk.staff',
        'phone': null,
        'password': 'longenough',
        'shopIds': [1, 2],
      });
      expect(u.id, 7);
    });
  });
}