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

import '../../../core/providers/auth_provider.dart';
import '../../../core/providers/locale_provider.dart';
import '../../../core/theme/app_theme.dart';
import '../../../core/utils/currency_formatter.dart';
import '../../../core/widgets/gradient_app_bar.dart';
import '../../../core/widgets/pill_tabs.dart';
import '../../../models/finance_entry.dart';
import 'clinic_finance_repository.dart';

enum _FinanceSort { newestFirst, byAmountDesc, byAmountAsc }

class ClinicFinanceScreen extends ConsumerStatefulWidget {
  const ClinicFinanceScreen({super.key});

  @override
  ConsumerState<ClinicFinanceScreen> createState() =>
      _ClinicFinanceScreenState();
}

class _ClinicFinanceScreenState extends ConsumerState<ClinicFinanceScreen>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;
  late Future<_ClinicFinanceHeaderData> _headerFuture;
  _FinanceSort _sort = _FinanceSort.newestFirst;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 2, vsync: this);
    _tabController.addListener(() {
      if (mounted) setState(() {});
    });
    _loadSummary();
  }

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

  void _loadSummary() {
    final tenantId = ref.read(authProvider).activeTenant!.tenant.id;
    setState(() {
      _headerFuture = Future.wait([
        ClinicFinanceRepository.instance.summary(tenantId),
        ClinicFinanceRepository.instance.byCounterparty(tenantId),
      ]).then(
        (results) => _ClinicFinanceHeaderData(
          summary: results[0] as Map<String, double>,
          counterparties: results[1] as List<CounterpartyFinanceSummary>,
        ),
      );
    });
  }

  Future<void> _showSortOptions() async {
    final s = ref.read(stringsProvider);
    final result = await showSortSheet(
      context,
      title: s.sort,
      options: [s.sortNewest, s.sortAmountDesc, s.sortAmountAsc],
      current: _sort.index,
    );
    if (result != null) {
      setState(() => _sort = _FinanceSort.values[result]);
    }
  }

  @override
  Widget build(BuildContext context) {
    final isSortActive = _sort != _FinanceSort.newestFirst;
    final s = ref.watch(stringsProvider);
    final currencyCode =
        ref.watch(authProvider).activeTenant?.tenant.defaultCurrency ?? 'TRY';

    return Scaffold(
      backgroundColor: AppColors.background,
      appBar: GradientAppBar(
        title: s.finance,
        category: s.clinicCategory,
        actions: [
          IconButton(
            onPressed: _showSortOptions,
            tooltip: 'Sırala',
            icon: Badge(
              isLabelVisible: isSortActive,
              smallSize: 8,
              backgroundColor: AppColors.accent,
              child: const Icon(Icons.sort_rounded),
            ),
          ),
        ],
      ),
      body: Column(
        children: [
          FutureBuilder<_ClinicFinanceHeaderData>(
            future: _headerFuture,
            builder: (ctx, snap) {
              if (snap.connectionState == ConnectionState.waiting) {
                return const LinearProgressIndicator(color: AppColors.accent);
              }
              final data = snap.data ??
                  const _ClinicFinanceHeaderData(
                    summary: {'pending': 0.0, 'paid': 0.0},
                    counterparties: [],
                  );
              return Column(
                children: [
                  Padding(
                    padding: const EdgeInsets.all(16),
                    child: Row(
                      children: [
                        Expanded(
                          child: _SummaryCard(
                            label: 'Açık Borç',
                            amount: data.summary['pending'] ?? 0.0,
                            currencyCode: currencyCode,
                            color: AppColors.pending,
                            bgColor: AppColors.pendingBg,
                            icon: Icons.hourglass_empty_rounded,
                          ),
                        ),
                        const SizedBox(width: 12),
                        Expanded(
                          child: _SummaryCard(
                            label: 'Onaylanan Ödeme',
                            amount: data.summary['paid'] ?? 0.0,
                            currencyCode: currencyCode,
                            color: AppColors.success,
                            bgColor: AppColors.successBg,
                            icon: Icons.check_circle_outline,
                          ),
                        ),
                      ],
                    ),
                  ),
                  if (data.counterparties.isNotEmpty)
                    Padding(
                      padding: const EdgeInsets.fromLTRB(16, 0, 16, 12),
                      child: _CounterpartySummaryList(
                        title: 'Laboratuvar Bazlı Borç',
                        items: data.counterparties,
                        currencyCode: currencyCode,
                      ),
                    ),
                ],
              );
            },
          ),
          PillTabs(
            tabs: [s.pending, s.collected],
            selected: _tabController.index,
            onSelect: (i) => _tabController.animateTo(i),
          ),
          Expanded(
            child: TabBarView(
              controller: _tabController,
              children: [
                _FinanceTab(
                  status: 'pending',
                  sort: _sort,
                  onPaymentMade: _loadSummary,
                  currencyCode: currencyCode,
                ),
                _FinanceTab(
                  status: 'paid',
                  sort: _sort,
                  onPaymentMade: _loadSummary,
                  currencyCode: currencyCode,
                ),
              ],
            ),
          ),
        ],
      ),
    );
  }
}

class _ClinicFinanceHeaderData {
  const _ClinicFinanceHeaderData({
    required this.summary,
    required this.counterparties,
  });

  final Map<String, double> summary;
  final List<CounterpartyFinanceSummary> counterparties;
}

class _SummaryCard extends StatelessWidget {
  const _SummaryCard({
    required this.label,
    required this.amount,
    required this.currencyCode,
    required this.color,
    required this.bgColor,
    required this.icon,
  });

  final String label;
  final double amount;
  final String currencyCode;
  final Color color;
  final Color bgColor;
  final IconData icon;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: AppColors.surface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: AppColors.border),
        boxShadow: [
          BoxShadow(
              color: Colors.black.withValues(alpha: 0.06),
              blurRadius: 12,
              offset: const Offset(0, 4))
        ],
      ),
      child: Row(
        children: [
          Container(
            width: 44,
            height: 44,
            decoration: BoxDecoration(
                color: bgColor, borderRadius: BorderRadius.circular(12)),
            child: Icon(icon, color: color, size: 22),
          ),
          const SizedBox(width: 12),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  CurrencyFormatter.format(amount, currencyCode),
                  style: TextStyle(
                      fontSize: 20,
                      fontWeight: FontWeight.w800,
                      color: color,
                      height: 1),
                ),
                const SizedBox(height: 3),
                Text(label,
                    style: const TextStyle(
                        fontSize: 12,
                        color: AppColors.textSecondary,
                        fontWeight: FontWeight.w500)),
              ],
            ),
          ),
        ],
      ),
    );
  }
}

class _FinanceTab extends ConsumerStatefulWidget {
  const _FinanceTab({
    required this.status,
    required this.sort,
    required this.onPaymentMade,
    required this.currencyCode,
  });

  final String status;
  final _FinanceSort sort;
  final VoidCallback onPaymentMade;
  final String currencyCode;

  @override
  ConsumerState<_FinanceTab> createState() => _FinanceTabState();
}

class _FinanceTabState extends ConsumerState<_FinanceTab> {
  late Future<List<FinanceEntry>> _future;

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

  void _load() {
    final tenantId = ref.read(authProvider).activeTenant!.tenant.id;
    setState(() {
      _future = ClinicFinanceRepository.instance.listEntries(
        tenantId,
        status: widget.status,
        limit: 100,
      );
    });
  }

  List<FinanceEntry> _sorted(List<FinanceEntry> entries) {
    final list = List<FinanceEntry>.from(entries);
    switch (widget.sort) {
      case _FinanceSort.newestFirst:
        list.sort((a, b) {
          final da =
              a.dateCreated != null ? DateTime.tryParse(a.dateCreated!) : null;
          final db =
              b.dateCreated != null ? DateTime.tryParse(b.dateCreated!) : null;
          if (da == null && db == null) return 0;
          if (da == null) return 1;
          if (db == null) return -1;
          return db.compareTo(da);
        });
      case _FinanceSort.byAmountDesc:
        list.sort((a, b) => b.amount.compareTo(a.amount));
      case _FinanceSort.byAmountAsc:
        list.sort((a, b) => a.amount.compareTo(b.amount));
    }
    return list;
  }

  Future<void> _reportPayment(FinanceEntry entry) async {
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Ödeme Bildir'),
        content: Text(
          '${entry.counterpartyName ?? "Bu kayıt"} için '
          '${CurrencyFormatter.format(entry.amount, widget.currencyCode)} tutarındaki borcu '
          'laboratuvara ödendi olarak bildirmek istiyor musunuz?',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: const Text('İptal'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(ctx, true),
            child: const Text('Bildir'),
          ),
        ],
      ),
    );
    if (confirmed != true || !mounted) return;
    try {
      await ClinicFinanceRepository.instance.reportPayment(entry.id);
      _load();
      widget.onPaymentMade();
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(
            content: Text('Ödeme bildirildi. Laboratuvar onayı bekleniyor.'),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Hata: $e')),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return RefreshIndicator(
      color: AppColors.accent,
      onRefresh: () async => _load(),
      child: FutureBuilder<List<FinanceEntry>>(
        future: _future,
        builder: (ctx, snap) {
          if (snap.connectionState == ConnectionState.waiting) {
            return const Center(
                child: CircularProgressIndicator(color: AppColors.accent));
          }
          if (snap.hasError) {
            return Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Container(
                    width: 64,
                    height: 64,
                    decoration: BoxDecoration(
                        color: AppColors.cancelledBg,
                        borderRadius: BorderRadius.circular(16)),
                    child: const Icon(Icons.wifi_off_rounded,
                        color: AppColors.cancelled, size: 30),
                  ),
                  const SizedBox(height: 16),
                  Text('Hata: ${snap.error}',
                      style: const TextStyle(color: AppColors.textSecondary)),
                  const SizedBox(height: 12),
                  FilledButton.icon(
                    onPressed: _load,
                    icon: const Icon(Icons.refresh_rounded, size: 18),
                    label: const Text('Tekrar Dene'),
                  ),
                ],
              ),
            );
          }
          final entries = _sorted(snap.data!);
          if (entries.isEmpty) {
            return Center(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Container(
                    width: 72,
                    height: 72,
                    decoration: BoxDecoration(
                        color: AppColors.inProgressBg,
                        borderRadius: BorderRadius.circular(20)),
                    child: const Icon(Icons.receipt_long_outlined,
                        color: AppColors.inProgress, size: 32),
                  ),
                  const SizedBox(height: 16),
                  const Text(
                    'Kayıt bulunamadı',
                    style: TextStyle(
                        fontSize: 16,
                        fontWeight: FontWeight.w600,
                        color: AppColors.textPrimary),
                  ),
                ],
              ),
            );
          }
          return ListView.builder(
            padding: const EdgeInsets.fromLTRB(16, 12, 16, 24),
            itemCount: entries.length,
            itemBuilder: (context, index) {
              final entry = entries[index];
              final isPending = entry.status == FinanceStatus.pending;
              final isReported = entry.status == FinanceStatus.reported;
              final statusColor = isPending
                  ? AppColors.pending
                  : isReported
                      ? AppColors.accent
                      : AppColors.success;
              final statusBg = isPending
                  ? AppColors.pendingBg
                  : isReported
                      ? AppColors.inProgressBg
                      : AppColors.successBg;

              return Padding(
                padding: const EdgeInsets.only(bottom: 10),
                child: Material(
                  color: AppColors.surface,
                  borderRadius: BorderRadius.circular(14),
                  child: InkWell(
                    onTap: isPending ? () => _reportPayment(entry) : null,
                    borderRadius: BorderRadius.circular(14),
                    child: Container(
                      padding: const EdgeInsets.all(14),
                      decoration: BoxDecoration(
                          borderRadius: BorderRadius.circular(14),
                          border: Border.all(color: AppColors.border),
                          boxShadow: [
                            BoxShadow(
                                color: Colors.black.withValues(alpha: 0.04),
                                blurRadius: 8,
                                offset: const Offset(0, 2))
                          ]),
                      child: Row(
                        children: [
                          Container(
                            width: 44,
                            height: 44,
                            decoration: BoxDecoration(
                                color: statusBg,
                                borderRadius: BorderRadius.circular(12)),
                            child: Icon(
                              isPending
                                  ? Icons.hourglass_empty_rounded
                                  : isReported
                                      ? Icons.verified_outlined
                                      : Icons.check_circle_outline,
                              color: statusColor,
                              size: 22,
                            ),
                          ),
                          const SizedBox(width: 12),
                          Expanded(
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.start,
                              children: [
                                Row(
                                  children: [
                                    Expanded(
                                      child: Text(
                                        entry.counterpartyName ?? 'Bilinmiyor',
                                        style: const TextStyle(
                                            fontSize: 15,
                                            fontWeight: FontWeight.w600,
                                            color: AppColors.textPrimary),
                                      ),
                                    ),
                                    Text(
                                      CurrencyFormatter.format(
                                          entry.amount, widget.currencyCode),
                                      style: TextStyle(
                                          fontSize: 15,
                                          fontWeight: FontWeight.w700,
                                          color: statusColor),
                                    ),
                                  ],
                                ),
                                if (entry.patientCode != null) ...[
                                  const SizedBox(height: 2),
                                  Text(
                                    'Protokol: ${entry.patientCode}',
                                    style: const TextStyle(
                                        fontSize: 12,
                                        color: AppColors.textSecondary),
                                  ),
                                ],
                                if (entry.dateCreated != null) ...[
                                  const SizedBox(height: 2),
                                  Text(
                                    _formatDate(entry.dateCreated!),
                                    style: const TextStyle(
                                        fontSize: 12,
                                        color: AppColors.textMuted),
                                  ),
                                ],
                                if (isReported) ...[
                                  const SizedBox(height: 4),
                                  const Text(
                                    'Ödeme bildirildi, laboratuvar onayı bekleniyor.',
                                    style: TextStyle(
                                      fontSize: 12,
                                      color: AppColors.textSecondary,
                                    ),
                                  ),
                                ] else if (isPending) ...[
                                  const SizedBox(height: 4),
                                  const Text(
                                    'Dokunarak ödeme bildirimi yapabilirsiniz.',
                                    style: TextStyle(
                                      fontSize: 12,
                                      color: AppColors.textSecondary,
                                    ),
                                  ),
                                ],
                              ],
                            ),
                          ),
                          if (isPending) ...[
                            const SizedBox(width: 8),
                            Container(
                              padding: const EdgeInsets.symmetric(
                                  horizontal: 10, vertical: 5),
                              decoration: BoxDecoration(
                                color: AppColors.pending,
                                borderRadius: BorderRadius.circular(8),
                              ),
                              child: const Text(
                                'Öde',
                                style: TextStyle(
                                  color: Colors.white,
                                  fontSize: 12,
                                  fontWeight: FontWeight.w600,
                                ),
                              ),
                            ),
                          ],
                        ],
                      ),
                    ),
                  ),
                ),
              );
            },
          );
        },
      ),
    );
  }

  String _formatDate(String dateStr) {
    try {
      final d = DateTime.parse(dateStr);
      return '${d.day.toString().padLeft(2, '0')}.${d.month.toString().padLeft(2, '0')}.${d.year}';
    } catch (_) {
      return dateStr;
    }
  }
}

class _CounterpartySummaryList extends StatelessWidget {
  const _CounterpartySummaryList({
    required this.title,
    required this.items,
    required this.currencyCode,
  });

  final String title;
  final List<CounterpartyFinanceSummary> items;
  final String currencyCode;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.all(14),
      decoration: BoxDecoration(
        color: AppColors.surface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: AppColors.border),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            title,
            style: const TextStyle(
              fontSize: 14,
              fontWeight: FontWeight.w700,
              color: AppColors.textPrimary,
            ),
          ),
          const SizedBox(height: 10),
          for (final item in items.take(5)) ...[
            Row(
              children: [
                Expanded(
                  child: Text(
                    item.counterpartyName,
                    style: const TextStyle(
                      fontSize: 13,
                      color: AppColors.textPrimary,
                      fontWeight: FontWeight.w600,
                    ),
                  ),
                ),
                Text(
                  CurrencyFormatter.format(item.pendingAmount, currencyCode),
                  style: const TextStyle(
                    fontSize: 13,
                    color: AppColors.pending,
                    fontWeight: FontWeight.w700,
                  ),
                ),
              ],
            ),
            const SizedBox(height: 8),
          ],
        ],
      ),
    );
  }
}