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

import '../../models/store_info.dart';
import '../../services/device_service.dart';
import '../../services/org_service.dart';
import '../../services/api_client.dart';
import '../../utils/formatters.dart';
import '../../utils/i10n.dart';

/// 激活码管理页：门店选择、激活码信息、生成/重置。
class DeviceActivationPage extends ConsumerStatefulWidget {
  const DeviceActivationPage({super.key});

  @override
  ConsumerState<DeviceActivationPage> createState() =>
      _DeviceActivationPageState();
}

class _DeviceActivationPageState extends ConsumerState<DeviceActivationPage> {
  final OrgService _orgService = OrgService();
  final DeviceService _deviceService = DeviceService();

  AppLocalizations get t => AppLocalizations.of(context);

  List<StoreInfo> _stores = [];
  String? _selectedStoreId;
  bool _loadingStores = true;

  Map<String, dynamic>? _codeInfo;
  bool _loading = false;
  String? _error;

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

  Future<void> _loadStores() async {
    try {
      final stores = await _orgService.getMyStores();
      if (!mounted) return;
      setState(() {
        _stores = stores;
        _loadingStores = false;
        if (stores.isNotEmpty) {
          _selectedStoreId = stores.first.orgId;
        }
      });
      if (_selectedStoreId != null) {
        _loadCodeInfo();
      }
    } catch (e) {
      if (!mounted) return;
      setState(() => _loadingStores = false);
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(AppLocalizations.of(context).storeListLoadFailed(e.toString()))),
      );
    }
  }

  Future<void> _loadCodeInfo() async {
    if (_selectedStoreId == null) return;
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final info = await _deviceService.getActivationCodeInfo(
        _selectedStoreId!,
      );
      if (!mounted) return;
      setState(() {
        _codeInfo = info;
        _loading = false;
      });
    } catch (e) {
      if (!mounted) return;
      setState(() {
        _error = '$e';
        _loading = false;
      });
    }
  }

  void _showGenerateSheet() {
    if (_selectedStoreId == null) return;
    showModalBottomSheet(
          useSafeArea: true,
      context: context,
      isScrollControlled: true,
      builder: (ctx) => _GenerateCodeSheet(
        deviceService: _deviceService,
        orgId: _selectedStoreId!,
        onSaved: () {
          Navigator.pop(ctx);
          _loadCodeInfo();
        },
      ),
    );
  }

  Future<void> _resetCode() async {
    if (_selectedStoreId == null) return;
    final t = AppLocalizations.of(context);
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: Text(t.resetActivationCode),
        content: Text(t.resetActivationCodeConfirm),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: Text(t.cancel),
          ),
          TextButton(
            onPressed: () => Navigator.pop(ctx, true),
            style: TextButton.styleFrom(foregroundColor: Colors.orange),
            child: Text(t.reset),
          ),
        ],
      ),
    );
    if (confirmed != true) return;

    try {
      await _deviceService.resetActivationCode(_selectedStoreId!);
      if (!mounted) return;
      // 结果以页面中央弹窗展示（替代左下方 SnackBar）。
      _showResultDialog(
        isSuccess: true,
        title: t.activationCodeResetSuccess,
      );
      _loadCodeInfo();
    } catch (e) {
      if (!mounted) return;
      _showResultDialog(
        isSuccess: false,
        title: t.activationCodeResetFailed(formatApiError(e)),
      );
    }
  }

  /// 居中弹窗展示激活码重置结果（成功/失败）。
  ///
  /// 替代原左下角 SnackBar，保证用户清晰看到操作反馈。
  void _showResultDialog({
    required bool isSuccess,
    required String title,
  }) {
    final t = AppLocalizations.of(context);
    showDialog<void>(
      context: context,
      builder: (ctx) => AlertDialog(
        icon: Icon(
          isSuccess ? Icons.check_circle_outline : Icons.error_outline,
          color: isSuccess ? Colors.green : Colors.red,
          size: 42,
        ),
        title: Center(child: Text(title, textAlign: TextAlign.center)),
        actionsAlignment: MainAxisAlignment.center,
        actions: [
          FilledButton(
            onPressed: () => Navigator.pop(ctx),
            child: Text(t.confirm),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final t = AppLocalizations.of(context);
    return Scaffold(
      appBar: AppBar(
        automaticallyImplyLeading: false,
        title: Text(t.activationCodeManagement),
      ),
      body: Column(
        children: [
          _buildStoreSelector(),
          const Divider(height: 1),
          Expanded(child: _buildBody()),
        ],
      ),
    );
  }

  Widget _buildStoreSelector() {
    if (_loadingStores) {
      return const Padding(
        padding: EdgeInsets.all(16),
        child: Center(child: CircularProgressIndicator()),
      );
    }
    if (_stores.isEmpty) {
      return Padding(
        padding: const EdgeInsets.all(16),
        child: Text(t.noStoreAvailable),
      );
    }
    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 8, 16, 8),
      child: DropdownButtonFormField<String>(
        value: _selectedStoreId,
        decoration: InputDecoration(
          labelText: t.selectStore,
          border: OutlineInputBorder(),
          prefixIcon: Icon(Icons.store),
        ),
        items: _stores
            .map((s) => DropdownMenuItem(
                  value: s.orgId,
                  child: Text(s.name),
                ))
            .toList(),
        onChanged: (v) {
          setState(() => _selectedStoreId = v);
          _loadCodeInfo();
        },
      ),
    );
  }

  Widget _buildBody() {
    if (_selectedStoreId == null) {
      return Center(child: Text(t.pleaseSelectStoreFirst));
    }
    if (_loading) {
      return const Center(child: CircularProgressIndicator());
    }
    if (_error != null) {
      return Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Text(t.activationCodeLoadFailed(_error!)),
            const SizedBox(height: 8),
            FilledButton.tonal(
              onPressed: _loadCodeInfo,
              child: Text(t.retry),
            ),
          ],
        ),
      );
    }
    if (_codeInfo == null) {
      return Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Icon(Icons.vpn_key_outlined,
                size: 64,
                color: Theme.of(context).colorScheme.outline),
            const SizedBox(height: 16),
            Text(t.noActivationCode),
            const SizedBox(height: 16),
            FilledButton.icon(
              onPressed: _showGenerateSheet,
              icon: const Icon(Icons.add),
              label: Text(t.generateActivationCode),
            ),
          ],
        ),
      );
    }
    return RefreshIndicator(
      onRefresh: _loadCodeInfo,
      child: ListView(
        padding: const EdgeInsets.all(16),
        physics: const AlwaysScrollableScrollPhysics(),
        children: [
          _buildCodeCard(),
          const SizedBox(height: 16),
          _buildInfoCard(),
          const SizedBox(height: 24),
          Row(
            children: [
              Expanded(
                child: FilledButton.icon(
                  onPressed: _showGenerateSheet,
                  icon: const Icon(Icons.refresh),
                  label: Text(t.generateActivationCode),
                ),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: OutlinedButton.icon(
                  onPressed: _resetCode,
                  style: OutlinedButton.styleFrom(
                    foregroundColor: Colors.orange,
                  ),
                  icon: const Icon(Icons.restart_alt),
                  label: Text(t.resetActivationCode),
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget _buildCodeCard() {
    final code = _codeInfo!['code']?.toString() ?? '';
    final theme = Theme.of(context);
    return Card(
      elevation: 2,
      child: Padding(
        padding: const EdgeInsets.all(20),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Icon(Icons.vpn_key,
                    color: theme.colorScheme.primary, size: 20),
                const SizedBox(width: 8),
                Text(t.currentActivationCode,
                    style: theme.textTheme.titleMedium
                        ?.copyWith(fontWeight: FontWeight.bold)),
              ],
            ),
            const SizedBox(height: 16),
            if (code.isEmpty)
              Container(
                width: double.infinity,
                padding: const EdgeInsets.all(16),
                decoration: BoxDecoration(
                  color: theme.colorScheme.surfaceContainerHighest,
                  borderRadius: BorderRadius.circular(8),
                ),
                child: Text(
                  t.activationCodeNoCodeHint,
                  style: const TextStyle(color: Colors.grey),
                ),
              )
            else
              Container(
                width: double.infinity,
                padding: const EdgeInsets.all(16),
                decoration: BoxDecoration(
                  color: theme.colorScheme.primaryContainer,
                  borderRadius: BorderRadius.circular(8),
                  border: Border.all(
                      color: theme.colorScheme.primary.withOpacity(0.4)),
                ),
                child: SelectableText(
                  code,
                  style: TextStyle(
                    fontSize: 18,
                    fontWeight: FontWeight.bold,
                    fontFamily: 'monospace',
                    color: theme.colorScheme.onPrimaryContainer,
                  ),
                ),
              ),
            if (code.isNotEmpty) ...[
              const SizedBox(height: 8),
              Row(
                mainAxisAlignment: MainAxisAlignment.end,
                children: [
                  TextButton.icon(
                    onPressed: () {
                      Clipboard.setData(ClipboardData(text: code));
                      ScaffoldMessenger.of(context).showSnackBar(
                        SnackBar(content: Text(t.activationCodeCopied)),
                      );
                    },
                    icon: const Icon(Icons.copy, size: 18),
                    label: Text(t.copy),
                  ),
                ],
              ),
            ],
          ],
        ),
      ),
    );
  }

  Widget _buildInfoCard() {
    final theme = Theme.of(context);
    final maxCount = _codeInfo!['maxActivateCount'];
    final activatedCount = _codeInfo!['activatedCount'];
    final createTime = _codeInfo!['createTime'];

    String _formatTime(dynamic t) {
      if (t == null) return '—';
      final text = t.toString().trim();
      if (text.isEmpty) return '—';
      final dt = DateTime.tryParse(text) ??
          DateTime.tryParse(text.replaceFirst(' ', 'T'));
      return dt != null ? Formatters.formatDateTime(dt) : text;
    }

    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          children: [
            _infoRow(
              theme,
              t.maxActivateCount,
              maxCount?.toString() ?? '—',
            ),
            _infoRow(
              theme,
              t.activatedCount,
              activatedCount?.toString() ?? '—',
            ),
            _infoRow(theme, t.createTime, _formatTime(createTime)),
          ],
        ),
      ),
    );
  }

  Widget _infoRow(ThemeData theme, String label, String value) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 6),
      child: Row(
        children: [
          SizedBox(
            width: 100,
            child: Text(
              label,
              style: theme.textTheme.bodyMedium
                  ?.copyWith(color: theme.colorScheme.onSurfaceVariant),
            ),
          ),
          Expanded(
            child: Text(value,
                style: theme.textTheme.bodyMedium
                    ?.copyWith(fontWeight: FontWeight.w600)),
          ),
        ],
      ),
    );
  }
}

/// 生成激活码表单。
class _GenerateCodeSheet extends StatefulWidget {
  const _GenerateCodeSheet({
    required this.deviceService,
    required this.orgId,
    required this.onSaved,
  });

  final DeviceService deviceService;
  final String orgId;
  final VoidCallback onSaved;

  @override
  State<_GenerateCodeSheet> createState() => _GenerateCodeSheetState();
}

class _GenerateCodeSheetState extends State<_GenerateCodeSheet> {
  final _formKey = GlobalKey<FormState>();
  final _countController = TextEditingController(text: '1');
  bool _saving = false;

  @override
  void dispose() {
    _countController.dispose();
    super.dispose();
  }

  Future<void> _save() async {
    final t = AppLocalizations.of(context);
    if (!_formKey.currentState!.validate()) return;
    setState(() => _saving = true);
    try {
      final count = int.parse(_countController.text.trim());
      await widget.deviceService.generateActivationCode(
        widget.orgId,
        count,
      );
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(t.activationCodeGenerated)),
      );
      widget.onSaved();
    } catch (e) {
      if (!mounted) return;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(t.generateFailedWithError(e.toString()))),
      );
    } finally {
      if (mounted) setState(() => _saving = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final t = AppLocalizations.of(context);
    return SingleChildScrollView(
      padding: EdgeInsets.only(
        bottom: MediaQuery.of(context).viewInsets.bottom,
      ),
      child: Container(
        padding: const EdgeInsets.all(20),
        child: Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            mainAxisSize: MainAxisSize.min,
            children: [
              Text(
                t.generateActivationCode,
                style: Theme.of(context)
                    .textTheme
                    .titleLarge
                    ?.copyWith(fontWeight: FontWeight.bold),
              ),
              const SizedBox(height: 8),
              Text(
                t.generateActivationCodeHint,
                style: TextStyle(
                  color: Theme.of(context).colorScheme.onSurfaceVariant,
                  fontSize: 13,
                ),
              ),
              const SizedBox(height: 20),
              TextFormField(
                controller: _countController,
                decoration: InputDecoration(
                  labelText: t.maxActivationCountLabel,
                  border: const OutlineInputBorder(),
                  prefixIcon: const Icon(Icons.looks),
                  helperText: t.maxActivationCountHint,
                ),
                keyboardType: TextInputType.number,
                inputFormatters: [FilteringTextInputFormatter.digitsOnly],
                validator: (v) {
                  final count = int.tryParse(v ?? '');
                  if (count == null || count <= 0) {
                    return t.positiveIntegerRequired;
                  }
                  return null;
                },
              ),
              const SizedBox(height: 24),
              SizedBox(
                width: double.infinity,
                child: FilledButton(
                  onPressed: _saving ? null : _save,
                  child: _saving
                      ? const SizedBox(
                          height: 20,
                          width: 20,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        )
                      : Text(t.generate),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}