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

import '../../auth/application/auth_notifier.dart';
import '../../profile/application/profile_notifier.dart';
import '../../profile/domain/user_profile.dart';
import '../application/teams_notifier.dart';
import '../domain/join_request.dart';
import '../domain/team.dart';
import '../infrastructure/teams_repository.dart';
import 'widgets/player_tile.dart';
import 'widgets/team_record_badge.dart';

/// Full-screen view of a single team: header (logo + record), summary stats,
/// and roster.
class TeamDetailScreen extends ConsumerWidget {
  const TeamDetailScreen({super.key, required this.teamId});

  final String teamId;

  /// Web reads better when long content is centered in a column; ~760px is
  /// the same max we use across other detail screens.
  static const double _maxContentWidth = 760;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final team = ref.watch(teamByIdProvider(teamId));

    if (team == null) {
      return Scaffold(
        appBar: AppBar(
          title: const Text('Team'),
          leading: IconButton(
            icon: const Icon(Icons.arrow_back),
            onPressed: () => context.go('/teams'),
          ),
        ),
        body: const Center(child: Text('Team not found.')),
      );
    }

    return Scaffold(
      appBar: AppBar(
        leading: IconButton(
          icon: const Icon(Icons.arrow_back),
          onPressed: () => context.go('/teams'),
        ),
        title: Text(team.name),
      ),
      body: Center(
        child: ConstrainedBox(
          constraints: const BoxConstraints(maxWidth: _maxContentWidth),
          child: _TeamDetailBody(team: team),
        ),
      ),
    );
  }
}

class _TeamDetailBody extends StatelessWidget {
  const _TeamDetailBody({required this.team});

  final Team team;

  @override
  Widget build(BuildContext context) {
    return CustomScrollView(
      slivers: [
        SliverToBoxAdapter(child: _TeamHeader(team: team)),
        SliverToBoxAdapter(child: _JoinTeamSection(team: team)),
        SliverToBoxAdapter(child: _StatsRow(team: team)),
        SliverToBoxAdapter(child: _ContactSection(team: team)),
        const SliverToBoxAdapter(child: _SectionDivider(title: 'Roster')),
        if (team.players.isEmpty)
          const SliverToBoxAdapter(child: _EmptyRoster())
        else
          SliverList.separated(
            itemCount: team.players.length,
            separatorBuilder: (_, _) => const Divider(height: 1),
            itemBuilder: (context, index) =>
                PlayerTile(player: team.players[index]),
          ),
        const SliverToBoxAdapter(child: SizedBox(height: 24)),
      ],
    );
  }
}

/// Renders one of four states for a logged-in player viewing a team:
///  * already on this team → 'YOUR TEAM' chip
///  * already on another team → no CTA
///  * pending request out → disabled 'Request pending' button
///  * no request yet → primary 'Request to join' OutlinedButton
///
/// Returns SizedBox.shrink for managers, admins, viewers, or while role is
/// resolving — they have no use for the action.
class _JoinTeamSection extends ConsumerWidget {
  const _JoinTeamSection({required this.team});

  final Team team;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final user = ref.watch(authNotifierProvider).valueOrNull;
    final role = ref.watch(currentUserRoleProvider);
    final profile = ref.watch(currentProfileProvider).valueOrNull;

    if (user == null || role != UserRole.player || profile == null) {
      return const SizedBox.shrink();
    }

    // Player is already on this team.
    if (profile.teamId == team.id) {
      return Padding(
        padding: const EdgeInsets.fromLTRB(16, 4, 16, 4),
        child: Align(
          alignment: Alignment.center,
          child: Container(
            padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 6),
            decoration: BoxDecoration(
              color: Colors.green.withValues(alpha: 0.18),
              borderRadius: BorderRadius.circular(20),
            ),
            child: Text(
              'YOUR TEAM',
              style: Theme.of(context).textTheme.labelMedium?.copyWith(
                color: Colors.green.shade300,
                fontWeight: FontWeight.w800,
                letterSpacing: 1.2,
              ),
            ),
          ),
        ),
      );
    }

    // Player is on a different team — no join CTA shown.
    if (profile.hasTeam) {
      return const SizedBox.shrink();
    }

    final requestsAsync = ref.watch(
      joinRequestsForPlayerProvider(user.uid),
    );

    return requestsAsync.when(
      loading: () => const SizedBox(height: 0),
      error: (_, _) => const SizedBox.shrink(),
      data: (requests) {
        final hasPendingForThisTeam = requests.any(
          (r) =>
              r.teamId == team.id && r.status == JoinRequestStatus.pending,
        );
        return Padding(
          padding: const EdgeInsets.fromLTRB(20, 4, 20, 8),
          child: hasPendingForThisTeam
              ? OutlinedButton.icon(
                  onPressed: null,
                  icon: const Icon(Icons.hourglass_bottom, size: 18),
                  label: const Text('REQUEST PENDING'),
                )
              : OutlinedButton.icon(
                  onPressed: () => _submit(context, ref, profile),
                  icon: const Icon(Icons.person_add_alt_1, size: 18),
                  label: const Text('REQUEST TO JOIN'),
                ),
        );
      },
    );
  }

  Future<void> _submit(
    BuildContext context,
    WidgetRef ref,
    UserProfile profile,
  ) async {
    final messenger = ScaffoldMessenger.of(context);
    try {
      await ref.read(teamsRepositoryProvider).submitJoinRequest(
            teamId: team.id,
            teamName: team.name,
            playerId: profile.uid,
            playerName: profile.displayName.isEmpty
                ? profile.email
                : profile.displayName,
            playerEmail: profile.email,
          );
      messenger.showSnackBar(
        const SnackBar(content: Text('Request sent!')),
      );
    } catch (e) {
      messenger.showSnackBar(
        SnackBar(content: Text('Could not send request: $e')),
      );
    }
  }
}

class _TeamHeader extends StatelessWidget {
  const _TeamHeader({required this.team});

  final Team team;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final scheme = theme.colorScheme;
    final initial = team.name.isEmpty ? '?' : team.name.characters.first;

    final hasLogo = team.logoUrl != null && team.logoUrl!.isNotEmpty;

    return Padding(
      padding: const EdgeInsets.fromLTRB(20, 20, 20, 12),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          Container(
            width: 96,
            height: 96,
            alignment: Alignment.center,
            decoration: BoxDecoration(
              color: scheme.primaryContainer,
              shape: BoxShape.circle,
              boxShadow: [
                BoxShadow(
                  color: scheme.primary.withValues(alpha: 0.25),
                  blurRadius: 24,
                  spreadRadius: 2,
                ),
              ],
            ),
            child: hasLogo
                ? CircleAvatar(
                    radius: 48,
                    backgroundColor: scheme.primaryContainer,
                    backgroundImage: NetworkImage(team.logoUrl!),
                  )
                : Text(
                    initial.toUpperCase(),
                    style: TextStyle(
                      color: scheme.onPrimaryContainer,
                      fontWeight: FontWeight.w800,
                      fontSize: 44,
                    ),
                  ),
          ),
          const SizedBox(height: 16),
          Text(
            team.name,
            textAlign: TextAlign.center,
            style: theme.textTheme.headlineSmall?.copyWith(
              fontWeight: FontWeight.w800,
            ),
          ),
          if (team.description != null && team.description!.isNotEmpty) ...[
            const SizedBox(height: 8),
            Text(
              team.description!,
              textAlign: TextAlign.center,
              style: theme.textTheme.bodyMedium?.copyWith(
                color: scheme.onSurfaceVariant,
              ),
            ),
          ],
          const SizedBox(height: 16),
          TeamRecordBadge(
            wins: team.wins,
            draws: team.draws,
            losses: team.losses,
          ),
        ],
      ),
    );
  }
}

class _StatsRow extends StatelessWidget {
  const _StatsRow({required this.team});

  final Team team;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final scheme = theme.colorScheme;
    final winPct = (team.winPercentage * 100).round();
    final topScorer = team.topScorer;

    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
        decoration: BoxDecoration(
          color: scheme.surfaceContainerHighest,
          borderRadius: BorderRadius.circular(14),
          border: Border.all(color: scheme.outlineVariant),
        ),
        child: Row(
          children: [
            Expanded(
              child: _StatColumn(label: 'Games', value: '${team.totalGames}'),
            ),
            _VerticalDivider(color: scheme.outlineVariant),
            Expanded(
              child: _StatColumn(label: 'Win %', value: '$winPct%'),
            ),
            _VerticalDivider(color: scheme.outlineVariant),
            Expanded(
              child: _StatColumn(
                label: 'Top scorer',
                value: topScorer == null
                    ? '—'
                    : '${topScorer.name.split(' ').first} '
                          '(${topScorer.goalsScored})',
                small: true,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _ContactSection extends StatelessWidget {
  const _ContactSection({required this.team});

  final Team team;

  @override
  Widget build(BuildContext context) {
    final hasEmail = team.managerEmail.isNotEmpty;
    final hasPhone = team.managerPhone != null && team.managerPhone!.isNotEmpty;
    if (!hasEmail && !hasPhone) return const SizedBox.shrink();

    final theme = Theme.of(context);
    final scheme = theme.colorScheme;

    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        decoration: BoxDecoration(
          color: scheme.surfaceContainerHighest,
          borderRadius: BorderRadius.circular(14),
          border: Border.all(color: scheme.outlineVariant),
        ),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: <Widget>[
            Text(
              'CONTACT',
              style: theme.textTheme.labelSmall?.copyWith(
                color: scheme.onSurfaceVariant,
                letterSpacing: 0.8,
                fontWeight: FontWeight.w700,
              ),
            ),
            const SizedBox(height: 8),
            if (hasEmail)
              _ContactRow(icon: Icons.mail_outline, label: team.managerEmail),
            if (hasEmail && hasPhone) const SizedBox(height: 6),
            if (hasPhone)
              _ContactRow(
                icon: Icons.phone_outlined,
                label: team.managerPhone!,
              ),
          ],
        ),
      ),
    );
  }
}

class _ContactRow extends StatelessWidget {
  const _ContactRow({required this.icon, required this.label});

  final IconData icon;
  final String label;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final scheme = theme.colorScheme;
    return Row(
      children: <Widget>[
        Icon(icon, size: 18, color: scheme.primary),
        const SizedBox(width: 10),
        Expanded(
          child: Text(
            label,
            style: theme.textTheme.bodyMedium?.copyWith(
              color: scheme.onSurface,
            ),
            overflow: TextOverflow.ellipsis,
          ),
        ),
      ],
    );
  }
}

class _StatColumn extends StatelessWidget {
  const _StatColumn({
    required this.label,
    required this.value,
    this.small = false,
  });

  final String label;
  final String value;
  final bool small;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final scheme = theme.colorScheme;
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Text(
          value,
          maxLines: 1,
          overflow: TextOverflow.ellipsis,
          textAlign: TextAlign.center,
          style:
              (small
                      ? theme.textTheme.titleMedium
                      : theme.textTheme.headlineSmall)
                  ?.copyWith(
                    fontWeight: FontWeight.w800,
                    color: scheme.onSurface,
                  ),
        ),
        const SizedBox(height: 2),
        Text(
          label,
          style: theme.textTheme.labelSmall?.copyWith(
            color: scheme.onSurfaceVariant,
            letterSpacing: 0.4,
          ),
        ),
      ],
    );
  }
}

class _VerticalDivider extends StatelessWidget {
  const _VerticalDivider({required this.color});

  final Color color;

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 1,
      height: 36,
      margin: const EdgeInsets.symmetric(horizontal: 8),
      color: color,
    );
  }
}

class _SectionDivider extends StatelessWidget {
  const _SectionDivider({required this.title});

  final String title;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Padding(
      padding: const EdgeInsets.fromLTRB(20, 16, 20, 8),
      child: Row(
        children: [
          Text(
            title,
            style: theme.textTheme.titleMedium?.copyWith(
              fontWeight: FontWeight.w700,
            ),
          ),
          const SizedBox(width: 12),
          Expanded(child: Divider(color: theme.colorScheme.outlineVariant)),
        ],
      ),
    );
  }
}

class _EmptyRoster extends StatelessWidget {
  const _EmptyRoster();

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 24),
      child: Text(
        'No players on the roster yet.',
        style: theme.textTheme.bodyMedium?.copyWith(
          color: theme.colorScheme.onSurfaceVariant,
        ),
      ),
    );
  }
}