import 'dart:convert';

import 'package:flutter_test/flutter_test.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:http/http.dart' as http;
import 'package:http/testing.dart' as http_testing;
import 'package:nostr/nostr.dart' as nostr;
import 'package:pointycastle/digests/sha256.dart';
import 'package:buzz/shared/relay/relay.dart';

void main() {
  test('queryRelay sends NIP-98 auth over POST /query', () async {
    final keychain = nostr.Keys.generate();
    final nsec = keychain.nsec;
    http.Request? capturedRequest;
    final client = http_testing.MockClient((request) async {
      capturedRequest = request;
      return http.Response('[]', 200);
    });
    final session = RelaySessionNotifier(httpClient: client);
    final container = ProviderContainer(
      overrides: [
        relaySessionProvider.overrideWith(() => session),
        relayConfigProvider.overrideWith(
          () => _FakeRelayConfigNotifier(
            baseUrl: 'https://relay.example/base',
            nsec: nsec,
          ),
        ),
      ],
    );
    addTearDown(container.dispose);

    const filter = NostrFilter(
      kinds: EventKind.channelTimelineContentKinds,
      tags: {
        '#h': [_channelId],
      },
      limit: 50,
      extensions: {
        'top_level': true,
        'include_summaries': true,
        'include_aux': true,
      },
    );

    await container.read(relaySessionProvider.notifier).queryRelay([filter]);

    expect(capturedRequest, isNotNull);
    expect(capturedRequest!.method, 'POST');
    expect(capturedRequest!.url.toString(), 'https://relay.example/query');
    expect(capturedRequest!.headers['Content-Type'], 'application/json');
    expect(jsonDecode(capturedRequest!.body), [filter.toJson()]);

    final authHeader = capturedRequest!.headers['Authorization'];
    expect(authHeader, isNotNull);
    expect(authHeader, startsWith('Nostr '));
    final encoded = authHeader!.substring('Nostr '.length);
    final decoded = utf8.decode(base64Url.decode(base64Url.normalize(encoded)));
    final authEvent = jsonDecode(decoded) as Map<String, dynamic>;
    final tags = (authEvent['tags'] as List<dynamic>)
        .map((tag) => (tag as List<dynamic>).cast<String>())
        .toList();
    final payloadHash = SHA256Digest()
        .process(utf8.encode(capturedRequest!.body))
        .map((byte) => byte.toRadixString(16).padLeft(2, '0'))
        .join();

    expect(authEvent['kind'], 27235);
    expect(authEvent['pubkey'], keychain.public);
    expect(
      tags,
      anyElement(equals(<String>['u', 'https://relay.example/query'])),
    );
    expect(tags, anyElement(equals(<String>['method', 'POST'])));
    expect(tags, anyElement(equals(<String>['payload', payloadHash])));
    expect(tags.any((tag) => tag.length == 2 && tag[0] == 'nonce'), isTrue);
  });

  test('queryRelay rejects malformed event arrays', () async {
    final keychain = nostr.Keys.generate();
    final session = RelaySessionNotifier(
      httpClient: http_testing.MockClient(
        (_) async => http.Response('[{}]', 200),
      ),
    );
    final container = ProviderContainer(
      overrides: [
        relaySessionProvider.overrideWith(() => session),
        relayConfigProvider.overrideWith(
          () => _FakeRelayConfigNotifier(
            baseUrl: 'https://relay.example',
            nsec: keychain.nsec,
          ),
        ),
      ],
    );
    addTearDown(container.dispose);

    await expectLater(
      container.read(relaySessionProvider.notifier).queryRelay(const []),
      throwsA(isA<FormatException>()),
    );
  });

  test('delivers the same live event to each matching subscription', () async {
    final session = RelaySessionNotifier();
    final firstEvents = <NostrEvent>[];
    final secondEvents = <NostrEvent>[];
    const filter = NostrFilter(
      kinds: EventKind.channelEventKinds,
      tags: {
        '#h': [_channelId],
      },
      limit: 50,
    );

    final firstSubscribe = session.subscribe(filter, firstEvents.add);
    session.debugHandleMessage(['EOSE', 'l-1']);
    final unsubscribeFirst = await firstSubscribe;

    final secondSubscribe = session.subscribe(filter, secondEvents.add);
    session.debugHandleMessage(['EOSE', 'l-2']);
    final unsubscribeSecond = await secondSubscribe;

    final event = _event();
    session.debugHandleMessage(['EVENT', 'l-1', event.toJson()]);
    session.debugHandleMessage(['EVENT', 'l-2', event.toJson()]);
    session.debugFlushEventBuffer();

    expect(firstEvents.map((event) => event.id), [event.id]);
    expect(secondEvents.map((event) => event.id), [event.id]);

    session.debugHandleMessage(['EVENT', 'l-1', event.toJson()]);
    session.debugFlushEventBuffer();

    expect(firstEvents.map((event) => event.id), [event.id]);
    expect(secondEvents.map((event) => event.id), [event.id]);

    unsubscribeFirst();
    unsubscribeSecond();
  });

  test('live subscribe fails when relay closes before ready', () async {
    final session = RelaySessionNotifier();
    const filter = NostrFilter(kinds: [EventKind.agentObserverFrame], limit: 0);

    final subscribe = session.subscribe(filter, (_) {});
    session.debugHandleMessage([
      'CLOSED',
      'l-1',
      'restricted: p-gated events require #p matching your pubkey',
    ]);

    await expectLater(
      subscribe,
      throwsA(
        isA<Exception>().having(
          (error) => error.toString(),
          'message',
          contains('p-gated events require #p'),
        ),
      ),
    );
  });

  test(
    'live onClosed callback runs when relay closes an open subscription',
    () async {
      final session = RelaySessionNotifier();
      final closedMessages = <String>[];
      const filter = NostrFilter(
        kinds: [EventKind.agentObserverFrame],
        limit: 0,
      );

      final subscribe = session.subscribe(
        filter,
        (_) {},
        onClosed: closedMessages.add,
      );
      session.debugHandleMessage(['EOSE', 'l-1']);
      final unsubscribe = await subscribe;
      session.debugHandleMessage([
        'CLOSED',
        'l-1',
        'restricted: no longer valid',
      ]);

      expect(closedMessages, ['restricted: no longer valid']);
      unsubscribe();
    },
  );
}

const _channelId = '11111111-1111-4111-8111-111111111111';

class _FakeRelayConfigNotifier extends RelayConfigNotifier {
  final String _baseUrl;
  final String? _nsec;

  _FakeRelayConfigNotifier({required String baseUrl, required String? nsec})
    : _baseUrl = baseUrl,
      _nsec = nsec;

  @override
  RelayConfig build() => RelayConfig(baseUrl: _baseUrl, nsec: _nsec);
}

NostrEvent _event() {
  return const NostrEvent(
    id: 'event-1',
    pubkey: 'alice',
    createdAt: 20,
    kind: EventKind.streamMessageV2,
    tags: [
      ['h', _channelId],
    ],
    content: 'hello',
    sig: 'sig',
  );
}