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

import '../state/providers.dart';
import '../subsonic/credentials.dart';
import '../theme/tokens.dart';

/// Open the add/edit-server sheet. Pass [initial] to edit an existing saved
/// server (its password is reused if the field is left blank).
Future<void> showConnectSheet(BuildContext context,
    {SubsonicCredentials? initial}) {
  return showModalBottomSheet<void>(
    context: context,
    backgroundColor: TimbreColors.background,
    isScrollControlled: true,
    builder: (_) => _ConnectSheet(initial: initial),
  );
}

/// Open the server switcher: pick an active server, or add a new one.
Future<void> showServerSheet(BuildContext context) {
  return showModalBottomSheet<void>(
    context: context,
    backgroundColor: TimbreColors.background,
    isScrollControlled: true,
    builder: (_) => const _ServerSheet(),
  );
}

/// Lists saved servers (tap to switch) with an "Add server" action.
class _ServerSheet extends ConsumerWidget {
  const _ServerSheet();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final conn = ref.watch(connectionProvider);
    final accent = Theme.of(context).colorScheme.primary;
    return SafeArea(
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: TimbreSpacing.lg),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: TimbreSpacing.xl),
              child: Text('Servers',
                  style: TextStyle(color: accent, fontWeight: FontWeight.w700)),
            ),
            const SizedBox(height: TimbreSpacing.md),
            if (conn.servers.isEmpty)
              const Padding(
                padding: EdgeInsets.symmetric(
                    horizontal: TimbreSpacing.xl, vertical: TimbreSpacing.md),
                child: Text('No servers saved yet.',
                    style: TextStyle(color: TimbreColors.dimmed)),
              )
            else
              for (final s in conn.servers)
                _ServerRow(
                  creds: s,
                  active: s.id == conn.activeId,
                  onTap: () {
                    // Grab the notifier before popping — this widget's `ref` is
                    // disposed with the sheet.
                    final notifier = ref.read(connectionProvider.notifier);
                    Navigator.of(context).pop();
                    notifier.switchTo(s.id);
                  },
                ),
            const SizedBox(height: TimbreSpacing.sm),
            InkWell(
              onTap: () {
                // Capture the navigator's (still-mounted) context before popping
                // this sheet, so the next sheet has a valid overlay to show in.
                final nav = Navigator.of(context);
                nav.pop();
                showConnectSheet(nav.context);
              },
              child: const Padding(
                padding: EdgeInsets.symmetric(
                    horizontal: TimbreSpacing.xl, vertical: TimbreSpacing.md),
                child: Row(
                  children: [
                    Icon(Icons.add, size: 16, color: TimbreColors.foreground),
                    SizedBox(width: TimbreSpacing.sm),
                    Text('Add server',
                        style: TextStyle(color: TimbreColors.foreground)),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _ServerRow extends StatelessWidget {
  const _ServerRow({
    required this.creds,
    required this.active,
    required this.onTap,
  });

  final SubsonicCredentials creds;
  final bool active;
  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    final accent = Theme.of(context).colorScheme.primary;
    return InkWell(
      onTap: onTap,
      child: Container(
        constraints:
            const BoxConstraints(minHeight: TimbreSpacing.minTouchTarget),
        padding: const EdgeInsets.symmetric(horizontal: TimbreSpacing.xl),
        child: Row(
          children: [
            Text(active ? '● ' : '○ ',
                style: TextStyle(
                    color: active ? accent : TimbreColors.dimmed)),
            Expanded(
              child: Text(
                creds.display,
                maxLines: 1,
                overflow: TextOverflow.ellipsis,
                style: TextStyle(
                  color: TimbreColors.foreground,
                  fontWeight: active ? FontWeight.w700 : FontWeight.w400,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _ConnectSheet extends ConsumerStatefulWidget {
  const _ConnectSheet({this.initial});

  final SubsonicCredentials? initial;

  @override
  ConsumerState<_ConnectSheet> createState() => _ConnectSheetState();
}

class _ConnectSheetState extends ConsumerState<_ConnectSheet> {
  final _url = TextEditingController();
  final _user = TextEditingController();
  final _pass = TextEditingController();
  final _alias = TextEditingController();
  bool _busy = false;
  String? _localError;

  bool get _isEdit => widget.initial != null;

  @override
  void initState() {
    super.initState();
    final initial = widget.initial;
    if (initial != null) {
      _url.text = initial.url;
      _user.text = initial.username;
      _alias.text = initial.alias ?? '';
    }
  }

  @override
  void dispose() {
    _url.dispose();
    _user.dispose();
    _pass.dispose();
    _alias.dispose();
    super.dispose();
  }

  /// Build credentials from the form. Returns null (and sets [_localError]) if
  /// required fields are missing. On edit, a blank password reuses the saved one.
  SubsonicCredentials? _readForm() {
    final url = _url.text.trim();
    final user = _user.text.trim();
    if (url.isEmpty || user.isEmpty) {
      setState(() => _localError = 'Server URL and username are required.');
      return null;
    }
    final password =
        _pass.text.isEmpty && _isEdit ? widget.initial!.password : _pass.text;
    if (password.isEmpty) {
      setState(() => _localError = 'Password is required.');
      return null;
    }
    final alias = _alias.text.trim();
    return SubsonicCredentials(
      url: url,
      username: user,
      password: password,
      alias: alias.isEmpty ? null : alias,
    );
  }

  Future<void> _connect() async {
    final creds = _readForm();
    if (creds == null) return;
    setState(() {
      _busy = true;
      _localError = null;
    });
    final ok = await ref.read(connectionProvider.notifier).connect(creds);
    if (!mounted) return;
    setState(() => _busy = false);
    if (ok) Navigator.of(context).pop();
  }

  Future<void> _save() async {
    final creds = _readForm();
    if (creds == null) return;
    setState(() {
      _busy = true;
      _localError = null;
    });
    await ref.read(connectionProvider.notifier).saveServer(creds);
    if (!mounted) return;
    setState(() => _busy = false);
    Navigator.of(context).pop();
  }

  @override
  Widget build(BuildContext context) {
    final conn = ref.watch(connectionProvider);
    final accent = Theme.of(context).colorScheme.primary;
    final error = _localError ??
        (conn.status == ConnStatus.error ? conn.error : null);
    return Padding(
      padding: EdgeInsets.only(
        left: TimbreSpacing.xl,
        right: TimbreSpacing.xl,
        top: TimbreSpacing.xl,
        bottom: MediaQuery.of(context).viewInsets.bottom + TimbreSpacing.xl,
      ),
      child: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          Text(_isEdit ? 'Edit server' : 'Add server',
              style: TextStyle(color: accent, fontWeight: FontWeight.w700)),
          const SizedBox(height: TimbreSpacing.lg),
          _field(_url, 'Server URL', 'https://navidrome.example.com',
              keyboard: TextInputType.url),
          _field(_user, 'Username', 'you'),
          _field(_pass, 'Password',
              _isEdit ? '•••••••• (unchanged)' : '••••••••',
              obscure: true),
          _field(_alias, 'Label (optional)', 'Home server'),
          if (error != null) ...[
            const SizedBox(height: TimbreSpacing.md),
            Text(error, style: const TextStyle(color: Color(0xFFE06C75))),
          ],
          const SizedBox(height: TimbreSpacing.lg),
          Row(
            children: [
              Expanded(
                child: OutlinedButton(
                  onPressed: _busy ? null : _save,
                  style: OutlinedButton.styleFrom(
                    foregroundColor: TimbreColors.foreground,
                    side: const BorderSide(color: TimbreColors.border),
                    shape: const RoundedRectangleBorder(),
                  ),
                  child: const Text('Save'),
                ),
              ),
              const SizedBox(width: TimbreSpacing.md),
              Expanded(
                child: FilledButton(
                  onPressed: _busy ? null : _connect,
                  style: FilledButton.styleFrom(
                    backgroundColor: accent,
                    foregroundColor: TimbreColors.background,
                    shape: const RoundedRectangleBorder(),
                  ),
                  child: _busy
                      ? const SizedBox(
                          height: 16,
                          width: 16,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        )
                      : const Text('Connect'),
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget _field(
    TextEditingController c,
    String label,
    String hint, {
    bool obscure = false,
    TextInputType? keyboard,
  }) {
    return Padding(
      padding: const EdgeInsets.only(bottom: TimbreSpacing.md),
      child: TextField(
        controller: c,
        obscureText: obscure,
        keyboardType: keyboard,
        autocorrect: false,
        enableSuggestions: false,
        style: const TextStyle(color: TimbreColors.foreground),
        decoration: InputDecoration(
          labelText: label,
          hintText: hint,
          labelStyle: const TextStyle(color: TimbreColors.dimmed),
          hintStyle: const TextStyle(color: TimbreColors.dimmed),
          enabledBorder: const OutlineInputBorder(
            borderRadius: BorderRadius.zero,
            borderSide: BorderSide(color: TimbreColors.border),
          ),
          focusedBorder: OutlineInputBorder(
            borderRadius: BorderRadius.zero,
            borderSide: BorderSide(color: Theme.of(context).colorScheme.primary),
          ),
        ),
      ),
    );
  }
}