import 'dart:developer';

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_svg/svg.dart';
import 'package:kmobile/data/repositories/transaction_repository.dart';
import 'package:kmobile/di/injection.dart';
import 'package:kmobile/features/accounts/screens/account_info_screen.dart';
import 'package:kmobile/features/accounts/screens/account_statement_screen.dart';
import 'package:kmobile/features/auth/controllers/auth_cubit.dart';
import 'package:kmobile/features/auth/controllers/auth_state.dart';
import 'package:kmobile/features/customer_info/screens/customer_info_screen.dart';
import 'package:kmobile/features/beneficiaries/screens/manage_beneficiaries_screen.dart';
import 'package:kmobile/features/enquiry/screens/enquiry_screen.dart';
import 'package:kmobile/features/fund_transfer/screens/fund_transfer_beneficiary_screen.dart';
import 'package:kmobile/features/quick_pay/screens/quick_pay_screen.dart';
import 'package:kmobile/security/secure_storage.dart';
import 'package:local_auth/local_auth.dart';
import 'package:material_symbols_icons/material_symbols_icons.dart';
import 'package:google_fonts/google_fonts.dart';
import 'package:shimmer/shimmer.dart';
import 'package:kmobile/data/models/transaction.dart';

class DashboardScreen extends StatefulWidget {
  const DashboardScreen({super.key});

  @override
  State<DashboardScreen> createState() => _DashboardScreenState();
}

class _DashboardScreenState extends State<DashboardScreen> {
  int selectedAccountIndex = 0;
  bool isVisible = false;
  bool isRefreshing = false;
  bool isBalanceLoading = false;
  bool _biometricPromptShown = false;
  bool _txLoading = false;
  List<Transaction> _transactions = [];
  bool _txInitialized = false;

  Future<void> _loadTransactions(String accountNo) async {
    setState(() {
      _txLoading = true;
      _transactions = [];
    });
    try {
      final repo = getIt<TransactionRepository>();
      final txs = await repo.fetchTransactions(accountNo);
      var fiveTxns = <Transaction>[];
      //only take the first 5 transactions
      if (txs.length > 5) {
        fiveTxns = txs.sublist(0, 5);
      } else {
        fiveTxns = txs;
      }
      setState(() => _transactions = fiveTxns);
    } catch (e) {
      log(accountNo, error: e);
      ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Failed to load transactions: $e')));
    } finally {
      setState(() => _txLoading = false);
    }
  }

  Future<void> _refreshAccountData(BuildContext context) async {
    setState(() {
      isRefreshing = true;
    });
    try {
      // Call your AuthCubit or repository to refresh user/accounts data
      await context.read<AuthCubit>().refreshUserData();
    } catch (e) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('Failed to refresh data')),
      );
    }
    setState(() {
      isRefreshing = false;
    });
  }

  Widget _buildBalanceShimmer() {
    return Shimmer.fromColors(
      baseColor: Colors.white.withOpacity(0.7),
      highlightColor: Colors.white.withOpacity(0.3),
      child: Container(
        width: 100,
        height: 32,
        color: Colors.white,
      ),
    );
  }

  String getProcessedFirstName(String? name) {
    if (name == null || name.trim().isEmpty) return '';
    // Remove common titles
    final titles = [
      'mr.',
      'mrs.',
      'ms.',
      'miss',
      'dr.',
      'shri',
      'smt.',
      'kumari'
    ];
    String processed = name.trim().toLowerCase();
    for (final title in titles) {
      if (processed.startsWith(title)) {
        processed = processed.replaceFirst(title, '').trim();
        break;
      }
    }
    // Take the first word (first name)
    final firstName = processed.split(' ').first;
    // Convert to title case
    if (firstName.isEmpty) return '';
    return firstName[0].toUpperCase() + firstName.substring(1);
  }

  String getFullAccountType(String? accountType) {
    if (accountType == null || accountType.isEmpty) return 'N/A';
    // Convert to title case
    switch (accountType.toLowerCase()) {
      case 'sa':
        return 'Savings Account';
      case 'ln':
        return 'Loan Account';
      case 'td':
        return 'Term Deposit Account';
      case 'rd':
        return 'Recurring Deposit Account';
      default:
        return 'Unknown Account Type';
    }
  }

  Future<void> _showBiometricOptInDialog() async {
    final storage = SecureStorage();
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (_) => AlertDialog(
        title: const Text('Enable Biometric Authentication'),
        content: const Text('Use fingerprint/face ID for faster login?'),
        actions: [
          TextButton(
            onPressed: () async {
              await storage.write('biometric_prompt_shown', 'true');
              Navigator.of(context).pop();
            },
            child: const Text('Later'),
          ),
          TextButton(
            onPressed: () async {
              final auth = LocalAuthentication();
              final canCheck = await auth.canCheckBiometrics;
              bool ok = false;
              if (canCheck) {
                ok = await auth.authenticate(
                  localizedReason: 'Scan to enable biometric login',
                );
              }
              if (ok) {
                await storage.write('biometric_enabled', 'true');
              }
              await storage.write('biometric_prompt_shown', 'true');
              Navigator.of(context).pop();
            },
            child: const Text('Enable'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return BlocListener<AuthCubit, AuthState>(
      listener: (context, state) async {
        if (state is Authenticated && !_biometricPromptShown) {
          _biometricPromptShown = true;
          final storage = getIt<SecureStorage>();
          final already = await storage.read('biometric_prompt_shown');
          if (already == null) {
            _showBiometricOptInDialog();
          }
        }
      },
      child: Scaffold(
        backgroundColor: const Color(0xfff5f9fc),
        appBar: AppBar(
          backgroundColor: const Color(0xfff5f9fc),
          automaticallyImplyLeading: false,
          title: Text(
            'kMobile',
            style: TextStyle(
                color: Theme.of(context).primaryColor,
                fontWeight: FontWeight.w500),
          ),
          actions: [
            Padding(
              padding: const EdgeInsets.only(right: 10.0),
              child: InkWell(
                borderRadius: BorderRadius.circular(20),
                onTap: () {
                  // Navigator.push(
                  //     context,
                  //     MaterialPageRoute(
                  //         builder: (context) => const Preference()));
                },
                child: CircleAvatar(
                  backgroundColor: Colors.grey[200],
                  radius: 20,
                  child: SvgPicture.asset(
                    'assets/images/avatar_male.svg',
                    width: 40,
                    height: 40,
                    fit: BoxFit.cover,
                  ),
                ),
              ),
            ),
          ],
        ),
        body: BlocBuilder<AuthCubit, AuthState>(builder: (context, state) {
          if (state is AuthLoading || state is AuthInitial) {
            return const Center(child: CircularProgressIndicator());
          }
          if (state is Authenticated) {
            final users = state.users;
            final currAccount = users[selectedAccountIndex];
            // first‐time load
            if (!_txInitialized) {
              _txInitialized = true;
              WidgetsBinding.instance.addPostFrameCallback((_) {
                _loadTransactions(currAccount.accountNo!);
              });
            }
            final firstName = getProcessedFirstName(currAccount.name);

            return SingleChildScrollView(
              physics: const AlwaysScrollableScrollPhysics(),
              child: Padding(
                padding: const EdgeInsets.symmetric(horizontal: 16.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Padding(
                      padding: const EdgeInsets.only(left: 8.0),
                      child: Text(
                        "Hi! $firstName",
                        style: GoogleFonts.montserrat().copyWith(
                            fontSize: 25,
                            color: Theme.of(context).primaryColorDark,
                            fontWeight: FontWeight.w700),
                      ),
                    ),
                    const SizedBox(height: 16),

                    // Account Info Card
                    Container(
                      padding: const EdgeInsets.symmetric(
                          horizontal: 18, vertical: 10),
                      decoration: BoxDecoration(
                        color: Theme.of(context).primaryColor,
                        borderRadius: BorderRadius.circular(16),
                      ),
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Row(
                            children: [
                              const Text("Account Number: ",
                                  style: TextStyle(
                                      color: Colors.white, fontSize: 12)),
                              DropdownButton<int>(
                                value: selectedAccountIndex,
                                dropdownColor: Theme.of(context).primaryColor,
                                underline: const SizedBox(),
                                icon: const Icon(Icons.keyboard_arrow_down),
                                iconEnabledColor: Colors.white,
                                style: const TextStyle(
                                    color: Colors.white, fontSize: 14),
                                items: List.generate(users.length, (index) {
                                  return DropdownMenuItem<int>(
                                    value: index,
                                    child: Text(
                                      users[index].accountNo ?? 'N/A',
                                      style: const TextStyle(
                                          color: Colors.white, fontSize: 14),
                                    ),
                                  );
                                }),
                                onChanged: (int? newIndex) async {
                                  if (newIndex == null ||
                                      newIndex == selectedAccountIndex) {
                                    return;
                                  }
                                  if (isBalanceLoading) return;
                                  if (isVisible) {
                                    setState(() {
                                      isBalanceLoading = true;
                                      selectedAccountIndex = newIndex;
                                    });
                                    await Future.delayed(
                                        const Duration(milliseconds: 200));
                                    setState(() {
                                      isBalanceLoading = false;
                                    });
                                  } else {
                                    setState(() {
                                      selectedAccountIndex = newIndex;
                                    });
                                  }
                                  await _loadTransactions(
                                      users[newIndex].accountNo!);
                                },
                              ),
                              const Spacer(),
                              IconButton(
                                icon: isRefreshing
                                    ? const SizedBox(
                                        width: 20,
                                        height: 20,
                                        child: CircularProgressIndicator(
                                          color: Colors.white,
                                          strokeWidth: 2,
                                        ),
                                      )
                                    : const Icon(Icons.refresh,
                                        color: Colors.white),
                                onPressed: isRefreshing
                                    ? null
                                    : () => _refreshAccountData(context),
                                tooltip: 'Refresh',
                              ),
                            ],
                          ),
                          Text(
                            getFullAccountType(currAccount.accountType),
                            style: const TextStyle(
                                color: Colors.white, fontSize: 16),
                          ),
                          const SizedBox(height: 4),
                          Row(
                            mainAxisAlignment: MainAxisAlignment.start,
                            children: [
                              const Text("₹ ",
                                  style: TextStyle(
                                      color: Colors.white,
                                      fontSize: 40,
                                      fontWeight: FontWeight.w700)),
                              isRefreshing || isBalanceLoading
                                  ? _buildBalanceShimmer()
                                  : Text(
                                      isVisible
                                          ? currAccount.currentBalance ?? '0.00'
                                          : '********',
                                      style: const TextStyle(
                                          color: Colors.white,
                                          fontSize: 40,
                                          fontWeight: FontWeight.w700)),
                              const Spacer(),
                              InkWell(
                                onTap: () async {
                                  if (isBalanceLoading) return;
                                  if (!isVisible) {
                                    setState(() {
                                      isBalanceLoading = true;
                                    });
                                    await Future.delayed(
                                        const Duration(seconds: 1));
                                    setState(() {
                                      isVisible = true;
                                      isBalanceLoading = false;
                                    });
                                  } else {
                                    setState(() {
                                      isVisible = false;
                                    });
                                  }
                                },
                                child: Icon(
                                    isVisible
                                        ? Symbols.visibility_lock
                                        : Symbols.visibility,
                                    color: Colors.white),
                              ),
                            ],
                          ),
                          const SizedBox(height: 15),
                        ],
                      ),
                    ),
                    const SizedBox(height: 18),
                    const Text(
                      'Quick Links',
                      style: TextStyle(fontSize: 17),
                    ),
                    const SizedBox(height: 16),

                    // Quick Links
                    GridView.count(
                      crossAxisCount: 4,
                      shrinkWrap: true,
                      physics: const NeverScrollableScrollPhysics(),
                      children: [
                        _buildQuickLink(Symbols.id_card, "Customer \n Info",
                            () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) => CustomerInfoScreen(
                                        user: users[selectedAccountIndex],
                                      )));
                        }),
                        _buildQuickLink(Symbols.currency_rupee, "Quick \n Pay",
                            () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) => QuickPayScreen(
                                      debitAccount: currAccount.accountNo!)));
                        }),
                        _buildQuickLink(Symbols.send_money, "Fund \n Transfer",
                            () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) =>
                                      const FundTransferBeneficiaryScreen()));
                        }, disable: true),
                        _buildQuickLink(
                            Symbols.server_person, "Account \n Info", () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) => AccountInfoScreen(
                                      user: users[selectedAccountIndex])));
                        }),
                        _buildQuickLink(
                            Symbols.receipt_long, "Account \n Statement", () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) => AccountStatementScreen(
                                        accountNo: users[selectedAccountIndex]
                                            .accountNo!,
                                      )));
                        }),
                        _buildQuickLink(
                            Symbols.checkbook, "Handle \n Cheque", () {},
                            disable: true),
                        _buildQuickLink(Icons.group, "Manage \n Beneficiary",
                            () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) =>
                                      const ManageBeneficiariesScreen()));
                        }, disable: true),
                        _buildQuickLink(Symbols.support_agent, "Contact \n Us",
                            () {
                          Navigator.push(
                              context,
                              MaterialPageRoute(
                                  builder: (context) => const EnquiryScreen()));
                        }),
                      ],
                    ),
                    const SizedBox(height: 5),

                    // Recent Transactions
                    const Text(
                      'Recent Transactions',
                      style: TextStyle(fontSize: 17),
                    ),
                    const SizedBox(height: 16),
                    if (_txLoading)
                      ..._buildTransactionShimmer()
                    else if (_transactions.isNotEmpty)
                      ..._transactions.map((tx) => ListTile(
                            leading: Icon(
                              tx.type == 'CR'
                                  ? Symbols.call_received
                                  : Symbols.call_made,
                              color:
                                  tx.type == 'CR' ? Colors.green : Colors.red,
                            ),
                            title: Text(
                              tx.name != null
                                  ? (tx.name!.length > 18
                                      ? tx.name!.substring(0, 20)
                                      : tx.name!)
                                  : '',
                              style: const TextStyle(fontSize: 14),
                            ),
                            subtitle: Text(tx.date ?? '',
                                style: const TextStyle(fontSize: 12)),
                            trailing: Text("₹${tx.amount}",
                                style: const TextStyle(fontSize: 16)),
                          ))
                    else
                      Padding(
                        padding: const EdgeInsets.symmetric(vertical: 24.0),
                        child: Center(
                          child: Text(
                            'No transactions found for this account.',
                            style: TextStyle(
                              fontSize: 16,
                              color: Colors.grey[600],
                            ),
                          ),
                        ),
                      ),
                  ],
                ),
              ),
            );
          }
          return const Center(child: Text("Something went wrong"));
        }),
      ),
    );
  }

  List<Widget> _buildTransactionShimmer() {
    return List.generate(3, (i) {
      return ListTile(
        leading: Shimmer.fromColors(
          baseColor: Colors.grey[300]!,
          highlightColor: Colors.grey[100]!,
          child: const CircleAvatar(radius: 12, backgroundColor: Colors.white),
        ),
        title: Shimmer.fromColors(
          baseColor: Colors.grey[300]!,
          highlightColor: Colors.grey[100]!,
          child: Container(height: 10, width: 100, color: Colors.white),
        ),
        subtitle: Shimmer.fromColors(
          baseColor: Colors.grey[300]!,
          highlightColor: Colors.grey[100]!,
          child: Container(height: 8, width: 60, color: Colors.white),
        ),
      );
    });
  }

  Widget _buildQuickLink(IconData icon, String label, VoidCallback onTap,
      {bool disable = false}) {
    return InkWell(
      onTap: disable ? null : onTap,
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          Icon(icon,
              size: 30,
              color: disable ? Colors.grey : Theme.of(context).primaryColor),
          const SizedBox(height: 4),
          Text(label,
              textAlign: TextAlign.center,
              style: const TextStyle(fontSize: 13)),
        ],
      ),
    );
  }
}