import 'dart:async';

import 'package:commons_core/commons_core.dart';
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';

import '../i18n/strings.g.dart';
import '../services/profile_cache.dart';
import '../services/social_connection.dart';
import '../services/social_service.dart';
import 'theme.dart';

/// "Your people": who you vouch for and who vouches for you, in human
/// language. Ego-centric by design — no roots, no parameters, no graph talk.
/// Reached from the profile; rows open the 1:1 chat.
class YourPeopleScreen extends StatefulWidget {
  const YourPeopleScreen({
    required this.social,
    required this.connection,
    this.profileCache,
    super.key,
  });

  final SocialService social;

  /// The shared relay connection (one per identity), carrying trust.
  final SocialConnection connection;

  /// Optional cache of peer display names; null in tests.
  final ProfileCache? profileCache;

  @override
  State<YourPeopleScreen> createState() => _YourPeopleScreenState();
}

class _YourPeopleScreenState extends State<YourPeopleScreen> {
  TrustTransport? _transport;
  bool _loading = true;
  bool _busy = false;
  List<String> _youVouchFor = const [];
  List<String> _vouchForYou = const [];
  final Map<String, String> _names = {};

  @override
  void initState() {
    super.initState();
    _init();
  }

  Future<void> _init() async {
    final session = await widget.connection.session();
    if (!mounted) return; // shared session is owned by the connection, not us
    _transport = session?.trust;
    await _load();
  }

  Future<void> _load() async {
    final transport = _transport;
    if (transport == null) {
      if (mounted) setState(() => _loading = false);
      return;
    }
    final self = widget.social.publicKeyHex;
    final now = DateTime.now();
    final certs = (await transport.allCertifications())
        .where((c) => c.isValidAt(now))
        .toList();
    final given = [
      for (final c in certs)
        if (c.issuer == self) c.subject,
    ]..sort();
    final received = [
      for (final c in certs)
        if (c.subject == self) c.issuer,
    ]..sort();
    final cache = widget.profileCache;
    if (cache != null) {
      for (final peer in {...given, ...received}) {
        final name = await cache.name(peer);
        if (name != null) _names[peer] = name;
      }
    }
    if (!mounted) return;
    setState(() {
      _youVouchFor = given;
      _vouchForYou = received;
      _loading = false;
    });
  }

  Future<void> _revoke(String peer) async {
    final t = context.t;
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(t.yourPeople.revokeConfirm),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context, false),
            child: Text(t.common.cancel),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(context, true),
            child: Text(t.yourPeople.revoke),
          ),
        ],
      ),
    );
    final transport = _transport;
    if (confirmed != true || transport == null || !mounted) return;
    setState(() => _busy = true);
    await transport.revoke(subjectPubkey: peer);
    await _load();
    if (mounted) setState(() => _busy = false);
  }

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    return Scaffold(
      appBar: AppBar(title: Text(t.yourPeople.title)),
      body: _loading
          ? const Center(child: CircularProgressIndicator())
          : _transport == null
              ? Center(
                  child: Padding(
                    padding: const EdgeInsets.all(32),
                    child: Text(
                      t.yourPeople.offline,
                      textAlign: TextAlign.center,
                      style: const TextStyle(color: seedMuted, fontSize: 15),
                    ),
                  ),
                )
              : ListView(
                  padding: const EdgeInsets.symmetric(vertical: 8),
                  children: [
                    Padding(
                      padding: const EdgeInsetsDirectional.fromSTEB(
                          16, 8, 16, 8),
                      child: Text(
                        t.yourPeople.help,
                        style:
                            const TextStyle(color: seedMuted, fontSize: 14),
                      ),
                    ),
                    _SectionHeader(label: t.yourPeople.youVouchFor),
                    if (_youVouchFor.isEmpty)
                      _EmptyNote(text: t.yourPeople.youVouchForEmpty)
                    else
                      for (final peer in _youVouchFor)
                        _PersonTile(
                          key: Key('yourPeople.given.$peer'),
                          name: _names[peer] ?? shortPubkey(peer),
                          onOpen: () => context.push('/chat/$peer'),
                          trailing: TextButton(
                            onPressed: _busy ? null : () => _revoke(peer),
                            child: Text(t.yourPeople.revoke),
                          ),
                        ),
                    const SizedBox(height: 12),
                    _SectionHeader(label: t.yourPeople.vouchesForYou),
                    if (_vouchForYou.isEmpty)
                      _EmptyNote(text: t.yourPeople.vouchesForYouEmpty)
                    else
                      for (final peer in _vouchForYou)
                        _PersonTile(
                          key: Key('yourPeople.received.$peer'),
                          name: _names[peer] ?? shortPubkey(peer),
                          onOpen: () => context.push('/chat/$peer'),
                        ),
                  ],
                ),
    );
  }
}

class _SectionHeader extends StatelessWidget {
  const _SectionHeader({required this.label});

  final String label;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsetsDirectional.fromSTEB(16, 12, 16, 4),
      child: Text(
        label,
        style: const TextStyle(
          color: seedGreen,
          fontSize: 13,
          fontWeight: FontWeight.w600,
        ),
      ),
    );
  }
}

class _EmptyNote extends StatelessWidget {
  const _EmptyNote({required this.text});

  final String text;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsetsDirectional.fromSTEB(16, 4, 16, 4),
      child: Text(
        text,
        style: const TextStyle(color: seedMuted, fontSize: 14),
      ),
    );
  }
}

class _PersonTile extends StatelessWidget {
  const _PersonTile({
    required this.name,
    required this.onOpen,
    this.trailing,
    super.key,
  });

  final String name;
  final VoidCallback onOpen;
  final Widget? trailing;

  @override
  Widget build(BuildContext context) {
    return ListTile(
      leading: const CircleAvatar(
        backgroundColor: seedAvatar,
        child: Icon(Icons.person, color: seedOnAvatar),
      ),
      title: Text(name),
      trailing: trailing,
      onTap: onOpen,
    );
  }
}