import 'dart:convert';
import 'package:flutter/material.dart';
import 'widgets/attachment_gallery_screen.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:lucide_icons/lucide_icons.dart';
import 'package:intl/intl.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart' as flutter_secure_storage;
import 'package:image_picker/image_picker.dart';
import 'package:flutter_image_compress/flutter_image_compress.dart';
import '../providers/providers.dart';
import '../data/models.dart';
import '../../../core/utils/snackbar_service.dart';
import '../../../core/services/ocr_service.dart';
import '../../../core/services/notification_service.dart';

class AddTransactionScreen extends ConsumerStatefulWidget {
  final Transaction? transaction;

  const AddTransactionScreen({super.key, this.transaction});

  @override
  ConsumerState<AddTransactionScreen> createState() => _AddTransactionScreenState();
}

class _AddTransactionScreenState extends ConsumerState<AddTransactionScreen> {
  final amountController = TextEditingController();
  final descriptionController = TextEditingController();
  DateTime selectedDate = DateTime.now();
  Category? selectedCategory;
  Wallet? fromWallet;
  Wallet? toWallet;
  bool isSaving = false;
  
  bool isRecurring = false;
  String recurringFrequency = 'MONTHLY';
  final List<String> frequencies = ['DAILY', 'WEEKLY', 'MONTHLY'];
  
  DateTime? dueDate;
  String alertSchedule = 'NONE';
  TimeOfDay alertTime = const TimeOfDay(hour: 9, minute: 0);
  
  final List<TransactionItem> lineItems = [];
  final List<TransactionAttachment> existingAttachments = [];
  final List<int> deletedAttachmentIds = [];
  final List<Map<String, String>> base64Attachments = [];
  final ImagePicker _picker = ImagePicker();
  String? _jwtToken;
  
  final OcrService _ocrService = OcrService();

  void _handleOcrResult(OcrResult? res) {
    if (res == null) return;
    if (res.amount != null) {
      setState(() {
        amountController.text = res.amount.toString();
      });
      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Found amount: Rs. ${res.amount}')));
    } else {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Could not find an amount in the receipt.')));
    }
  }

  @override
  void initState() {
    super.initState();
    const flutter_secure_storage.FlutterSecureStorage().read(key: 'jwt_token').then((value) {
      if (mounted) setState(() => _jwtToken = value);
    });
    if (widget.transaction != null) {
      final t = widget.transaction!;
      amountController.text = t.amount.toString();
      if (t.description != null) descriptionController.text = t.description!;
      selectedDate = t.date;
      if (t.items != null) lineItems.addAll(t.items!);
      if (t.attachments != null) existingAttachments.addAll(t.attachments!);
      dueDate = t.dueDate;
      alertSchedule = t.alertSchedule ?? 'NONE';
      if (t.alertTime != null) {
        final parts = t.alertTime!.split(':');
        if (parts.length >= 2) {
          alertTime = TimeOfDay(hour: int.tryParse(parts[0]) ?? 9, minute: int.tryParse(parts[1]) ?? 0);
        }
      }
    }
  }

  void _resolveInitialSelections(List<Category>? categories, List<Wallet>? wallets) {
    if (widget.transaction != null && selectedCategory == null && categories != null) {
      final matches = categories.where((c) => c.id == widget.transaction!.categoryId);
      if (matches.isNotEmpty) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (mounted) setState(() => selectedCategory = matches.first);
        });
      }
    }
    
    if (wallets != null && wallets.isNotEmpty && (fromWallet == null || toWallet == null)) {
      if (widget.transaction != null) {
        final fMatches = wallets.where((w) => w.id == widget.transaction!.fromWalletId);
        if (fMatches.isNotEmpty && fromWallet == null) {
          WidgetsBinding.instance.addPostFrameCallback((_) {
            if (mounted) setState(() => fromWallet = fMatches.first);
          });
        }
        final tMatches = wallets.where((w) => w.id == widget.transaction!.toWalletId);
        if (tMatches.isNotEmpty && toWallet == null) {
          WidgetsBinding.instance.addPostFrameCallback((_) {
            if (mounted) setState(() => toWallet = tMatches.first);
          });
        }
      }
    }

    if (widget.transaction == null) {
      if (categories != null && categories.length == 1 && selectedCategory == null) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (mounted) setState(() => selectedCategory = categories.first);
        });
      }
      if (wallets != null && wallets.length == 1 && toWallet == null) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (mounted) setState(() => toWallet = wallets.first);
        });
      }
    }
  }

  Future<void> _pickImage(ImageSource source) async {
    if ((base64Attachments.length + existingAttachments.length) >= 3) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Max 3 attachments allowed')));
      return;
    }
    final XFile? image = await _picker.pickImage(source: source);
    if (image != null) {
      final bytes = await image.readAsBytes();
      final compressedBytes = await FlutterImageCompress.compressWithList(
        bytes,
        minWidth: 600,
        quality: 80,
      );
      final base64String = base64Encode(compressedBytes);
      setState(() {
        base64Attachments.add({
          'fileName': image.name,
          'contentType': 'image/jpeg',
          'base64Content': base64String,
        });
      });
    }
  }

  void _addLineItem() {
    final nameCtrl = TextEditingController();
    final amountCtrl = TextEditingController();
    showDialog(
      context: context,
      builder: (ctx) => Dialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(28)),
        elevation: 0,
        backgroundColor: Colors.transparent,
        child: GestureDetector(
          onTap: () => FocusScope.of(context).unfocus(),
          child: Container(
            padding: const EdgeInsets.all(24),
            decoration: BoxDecoration(
              color: Colors.white,
              borderRadius: BorderRadius.circular(28),
              boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.1), blurRadius: 20, offset: const Offset(0, 10))],
            ),
            child: SingleChildScrollView(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  const Text('Add Item', style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold)),
                  const SizedBox(height: 24),
                  TextField(
                    controller: nameCtrl, 
                    style: const TextStyle(fontWeight: FontWeight.w500),
                    decoration: InputDecoration(
                      labelText: 'Item Name',
                      filled: true,
                      fillColor: Colors.grey.shade100,
                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                      focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                    )
                  ),
                  const SizedBox(height: 16),
                  TextField(
                    controller: amountCtrl, 
                    keyboardType: const TextInputType.numberWithOptions(decimal: true, signed: false),
                    textInputAction: TextInputAction.done,
                    style: const TextStyle(fontWeight: FontWeight.w500),
                    decoration: InputDecoration(
                      labelText: 'Amount',
                      prefixText: 'Rs. ',
                      prefixStyle: const TextStyle(color: Colors.black87, fontWeight: FontWeight.w500, fontSize: 16),
                      filled: true,
                      fillColor: Colors.grey.shade100,
                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                      focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                    )
                  ),
                  const SizedBox(height: 24),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.end,
                    children: [
                      TextButton(
                        onPressed: () => Navigator.pop(ctx), 
                        style: TextButton.styleFrom(foregroundColor: Colors.grey.shade700, padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12), shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12))),
                        child: const Text('Cancel', style: TextStyle(fontWeight: FontWeight.bold))
                      ),
                      const SizedBox(width: 12),
                      ElevatedButton(
                        onPressed: () {
                          if (nameCtrl.text.isNotEmpty && amountCtrl.text.isNotEmpty) {
                            setState(() {
                              lineItems.add(TransactionItem(name: nameCtrl.text, amount: double.parse(amountCtrl.text)));
                              double currentTotal = double.tryParse(amountController.text) ?? 0;
                              amountController.text = (currentTotal + double.parse(amountCtrl.text)).toString();
                            });
                            Navigator.pop(ctx);
                          }
                        }, 
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFF6C63FF),
                          foregroundColor: Colors.white,
                          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
                          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
                          elevation: 0,
                        ),
                        child: const Text('Add', style: TextStyle(fontWeight: FontWeight.bold))
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

  Future<void> _showCreateWalletDialog() async {
    final ctrl = TextEditingController();
    String selectedNature = 'CASH';
    final natures = ['CASH', 'SAVINGS', 'INVESTMENTS', 'LOAN', 'LENDING', 'PAYABLES', 'INCOME', 'EXPENSE'];
    
    await showDialog(
      context: context,
      builder: (ctx) => StatefulBuilder(
        builder: (context, setStateDialog) {
          return Dialog(
            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(28)),
            elevation: 0,
            backgroundColor: Colors.transparent,
            child: GestureDetector(
              onTap: () => FocusScope.of(context).unfocus(),
              child: Container(
                padding: const EdgeInsets.all(24),
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(28),
                  boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.1), blurRadius: 20, offset: const Offset(0, 10))],
                ),
                child: SingleChildScrollView(
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          Container(
                            padding: const EdgeInsets.all(10),
                            decoration: BoxDecoration(color: const Color(0xFF6C63FF).withValues(alpha: 0.1), shape: BoxShape.circle),
                            child: const Icon(LucideIcons.wallet, color: Color(0xFF6C63FF), size: 24),
                          ),
                          const SizedBox(width: 16),
                          const Text('New Account', style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold)),
                        ],
                      ),
                      const SizedBox(height: 24),
                      TextField(
                        controller: ctrl,
                        style: const TextStyle(fontWeight: FontWeight.w500),
                        decoration: InputDecoration(
                          hintText: 'Account Name (e.g. Household)',
                          filled: true,
                          fillColor: Colors.grey.shade100,
                          border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                          focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                        ),
                      ),
                      const SizedBox(height: 16),
                      DropdownButtonFormField<String>(
                        value: selectedNature,
                        style: const TextStyle(fontWeight: FontWeight.w500, color: Colors.black87),
                        decoration: InputDecoration(
                          labelText: 'Account Nature',
                          filled: true,
                          fillColor: Colors.grey.shade100,
                          border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                          focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                        ),
                        items: natures.map((n) => DropdownMenuItem(value: n, child: Text(n))).toList(),
                        onChanged: (val) {
                          if (val != null) setStateDialog(() => selectedNature = val);
                        },
                      ),
                      const SizedBox(height: 24),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.end,
                        children: [
                          TextButton(
                            onPressed: () => Navigator.pop(ctx),
                            style: TextButton.styleFrom(foregroundColor: Colors.grey.shade700, padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12), shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12))),
                            child: const Text('Cancel', style: TextStyle(fontWeight: FontWeight.bold)),
                          ),
                          const SizedBox(width: 12),
                          ElevatedButton(
                            onPressed: () async {
                              if (ctrl.text.isNotEmpty) {
                                await ref.read(walletProvider.notifier).createWallet(name: ctrl.text, nature: selectedNature);
                                if (context.mounted) Navigator.pop(ctx);
                              }
                            },
                            style: ElevatedButton.styleFrom(
                              backgroundColor: const Color(0xFF6C63FF),
                              foregroundColor: Colors.white,
                              padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
                              shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
                              elevation: 0,
                            ),
                            child: const Text('Create', style: TextStyle(fontWeight: FontWeight.bold)),
                          )
                        ],
                      ),
                    ],
                  ),
                ),
              ),
            ),
          );
        }
      ),
    );
  }

  void _showCategoryPicker() {
    showModalBottomSheet(
      context: context,
      builder: (ctx) {
        return Consumer(builder: (context, ref, child) {
          final categoriesState = ref.watch(categoryProvider);
          return Column(
            children: [
              ListTile(
                title: const Text('Select Category', style: TextStyle(fontWeight: FontWeight.bold)),
                trailing: IconButton(
                  icon: const Icon(LucideIcons.plus),
                  onPressed: () => _showQuickAdd('Category'),
                ),
              ),
              Expanded(
                child: categoriesState.when(
                  loading: () => const Center(child: CircularProgressIndicator()),
                  error: (e, st) => Center(child: Text('Error: $e')),
                  data: (categories) => ListView.builder(
                    itemCount: categories.length,
                    itemBuilder: (context, index) {
                      final c = categories[index];
                      return ListTile(
                        leading: const Icon(LucideIcons.tag),
                        title: Text(c.name),
                        onTap: () {
                          setState(() => selectedCategory = c);
                          Navigator.pop(context);
                        },
                      );
                    },
                  ),
                ),
              )
            ],
          );
        });
      },
    );
  }

  void _showWalletPicker(bool isDestination) {
    showModalBottomSheet(
      context: context,
      builder: (ctx) {
        return Consumer(builder: (context, ref, child) {
          final walletsState = ref.watch(walletProvider);
          return Column(
            children: [
              ListTile(
                title: Text(isDestination ? 'Select To Account' : 'Select From Account', style: const TextStyle(fontWeight: FontWeight.bold)),
                leading: IconButton(
                  icon: const Icon(LucideIcons.plus),
                  tooltip: 'Create New Account',
                  onPressed: () {
                    Navigator.pop(context); // Close picker
                    _showCreateWalletDialog();
                  },
                ),
                trailing: IconButton(
                  icon: const Icon(LucideIcons.x),
                  onPressed: () {
                    if (isDestination) {
                      setState(() => toWallet = null);
                    } else {
                      setState(() => fromWallet = null);
                    }
                    Navigator.pop(context);
                  },
                ),
              ),
              Expanded(
                child: walletsState.when(
                  loading: () => const Center(child: CircularProgressIndicator()),
                  error: (e, st) => Center(child: Text('Error: $e')),
                  data: (wallets) {
                    return ListView.builder(
                      itemCount: wallets.length,
                      itemBuilder: (context, index) {
                        final w = wallets[index];
                        return ListTile(
                          leading: const Icon(LucideIcons.wallet),
                          title: Text(w.name),
                          subtitle: Text('${w.nature ?? "CASH"} • Balance: Rs. ${w.balance}'),
                          onTap: () {
                            if (isDestination) {
                              setState(() => toWallet = w);
                            } else {
                              setState(() => fromWallet = w);
                            }
                            Navigator.pop(context);
                          },
                        );
                      },
                    );
                  }
                ),
              )
            ],
          );
        });
      },
    );
  }

  Future<void> _pickDate() async {
    final picked = await showDatePicker(
      context: context,
      initialDate: selectedDate,
      firstDate: DateTime(2000),
      lastDate: DateTime(2101),
    );
    if (picked != null && picked != selectedDate) {
      setState(() {
        selectedDate = picked;
      });
    }
  }

  void _showQuickAdd(String type) {
    Navigator.pop(context); 
    final ctrl = TextEditingController();
    showDialog(
      context: context,
      builder: (ctx) => Dialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(28)),
        elevation: 0,
        backgroundColor: Colors.transparent,
        child: GestureDetector(
          onTap: () => FocusScope.of(context).unfocus(),
          child: Container(
            padding: const EdgeInsets.all(24),
            decoration: BoxDecoration(
              color: Colors.white,
              borderRadius: BorderRadius.circular(28),
              boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.1), blurRadius: 20, offset: const Offset(0, 10))],
            ),
            child: SingleChildScrollView(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text('Add New $type', style: const TextStyle(fontSize: 20, fontWeight: FontWeight.bold)),
                  const SizedBox(height: 24),
                  TextField(
                    controller: ctrl,
                    textInputAction: TextInputAction.done,
                    style: const TextStyle(fontWeight: FontWeight.w500),
                    decoration: InputDecoration(
                      hintText: 'Name',
                      filled: true,
                      fillColor: Colors.grey.shade100,
                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                      focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                    ),
                  ),
                  const SizedBox(height: 24),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.end,
                    children: [
                      TextButton(
                        onPressed: () => Navigator.pop(ctx),
                        style: TextButton.styleFrom(foregroundColor: Colors.grey.shade700, padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12), shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12))),
                        child: const Text('Cancel', style: TextStyle(fontWeight: FontWeight.bold)),
                      ),
                      const SizedBox(width: 12),
                      ElevatedButton(
                        onPressed: () async {
                          if (ctrl.text.isEmpty) return;
                          if (type == 'Category') {
                            await ref.read(categoryProvider.notifier).addCategory(ctrl.text, 'tag');
                          }
                          if (mounted) Navigator.pop(ctx);
                        },
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFF6C63FF),
                          foregroundColor: Colors.white,
                          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
                          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
                          elevation: 0,
                        ),
                        child: const Text('Add', style: TextStyle(fontWeight: FontWeight.bold)),
                      )
                    ],
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

  Future<void> _saveTransaction() async {
    final amountText = amountController.text.trim();
    if (amountText.isEmpty) {
       ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Please enter an amount')));
       return;
    }

    if (toWallet == null) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Please select a To Account')));
      return;
    }

    // Check if From Account is mandatory
    bool fromAccountOptional = (toWallet?.nature == 'SAVINGS' || toWallet?.nature == 'INCOME');
    if (fromWallet == null && !fromAccountOptional) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Please select a From Account')));
      return;
    }

    if (fromWallet != null && toWallet != null && fromWallet?.id == toWallet?.id) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('From and To accounts cannot be the same')));
      return;
    }

    final amount = double.tryParse(amountText);
    if (amount == null) return;

    if (fromWallet != null && fromWallet!.balance < amount) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Insufficient balance in From Account')));
      return;
    }

    setState(() => isSaving = true);
    
    // Determine internal type based on natures
    String type = 'TRANSFER';
    if (fromWallet == null) {
      type = 'INCOME';
    } else if (toWallet == null) { // Though toWallet is mandatory, just in case
      type = 'EXPENSE';
    } else if (fromWallet?.nature == 'INCOME') {
      type = 'INCOME';
    } else if (toWallet?.nature == 'PAYABLES' || toWallet?.nature == 'EXPENSE') {
      type = 'EXPENSE';
    } else if (toWallet?.nature == 'INVESTMENTS') {
      type = 'INVESTMENT';
    }

    if (isRecurring && widget.transaction == null) {
      DateTime nextDate = selectedDate;
      if (recurringFrequency == 'DAILY') {
        nextDate = nextDate.add(const Duration(days: 1));
      } else if (recurringFrequency == 'WEEKLY') {
        nextDate = nextDate.add(const Duration(days: 7));
      } else if (recurringFrequency == 'MONTHLY') {
        nextDate = DateTime(nextDate.year, nextDate.month + 1, nextDate.day);
      }

      final rt = RecurringTransaction(
        id: 0,
        type: type,
        amount: amount,
        categoryId: selectedCategory?.id,
        fromWalletId: fromWallet?.id,
        toWalletId: toWallet?.id,
        frequency: recurringFrequency,
        description: descriptionController.text.trim(),
        nextExecutionDate: nextDate,
        status: 'ACTIVE',
      );
      await ref.read(recurringTransactionProvider.notifier).addRecurringTransaction(rt);
      
      final tx = Transaction(
        id: 0,
        type: type,
        amount: amount,
        date: selectedDate,
        description: descriptionController.text.trim(),
        categoryId: selectedCategory?.id,
        fromWalletId: fromWallet?.id,
        toWalletId: toWallet?.id,
        dueDate: dueDate,
        alertSchedule: alertSchedule == 'NONE' ? null : alertSchedule,
        alertTime: alertSchedule == 'NONE' ? null : '${alertTime.hour.toString().padLeft(2, '0')}:${alertTime.minute.toString().padLeft(2, '0')}:00',
        items: lineItems.isNotEmpty ? lineItems : null,
      );
      await ref.read(transactionProvider.notifier).addTransaction(tx, base64Attachments: base64Attachments);
    } else {
      final tx = Transaction(
        id: widget.transaction?.id ?? 0,
        type: type,
        amount: amount,
        date: selectedDate,
        description: descriptionController.text.trim(),
        categoryId: selectedCategory?.id,
        fromWalletId: fromWallet?.id,
        toWalletId: toWallet?.id,
        dueDate: dueDate,
        alertSchedule: alertSchedule == 'NONE' ? null : alertSchedule,
        alertTime: alertSchedule == 'NONE' ? null : '${alertTime.hour.toString().padLeft(2, '0')}:${alertTime.minute.toString().padLeft(2, '0')}:00',
        items: lineItems.isNotEmpty ? lineItems : null,
      );

      if (widget.transaction == null) {
        await ref.read(transactionProvider.notifier).addTransaction(tx, base64Attachments: base64Attachments);
      } else {
        await ref.read(transactionProvider.notifier).updateTransaction(
          tx, 
          base64Attachments: base64Attachments,
          deletedAttachmentIds: deletedAttachmentIds,
        );
      }
      
      if (alertSchedule != 'NONE' && dueDate != null) {
        DateTime alertDate = dueDate!;
        if (alertSchedule == '1_DAY_BEFORE') {
          alertDate = dueDate!.subtract(const Duration(days: 1));
        } else if (alertSchedule == '2_DAYS_BEFORE') {
          alertDate = dueDate!.subtract(const Duration(days: 2));
        } else if (alertSchedule == '1_WEEK_BEFORE') {
          alertDate = dueDate!.subtract(const Duration(days: 7));
        }
        
        final notifyDate = DateTime(alertDate.year, alertDate.month, alertDate.day, alertTime.hour, alertTime.minute);
        if (notifyDate.isAfter(DateTime.now())) {
          NotificationService().scheduleNotification(
            id: DateTime.now().millisecondsSinceEpoch.remainder(100000),
            title: 'Payment Due!',
            body: 'Rs. ${amount.toStringAsFixed(0)} is due for ${toWallet?.name}',
            scheduledDate: notifyDate,
          );
        }
      }
    }

    if (mounted) {
      SnackBarService.showSuccess(context, 'Transaction saved successfully');
      Navigator.pop(context);
    }
  }

  @override
  Widget build(BuildContext context) {
    final categoriesState = ref.watch(categoryProvider);
    final walletsState = ref.watch(walletProvider);

    _resolveInitialSelections(categoriesState.value, walletsState.value);

    return Scaffold(
      appBar: AppBar(
        title: Text(widget.transaction == null ? 'Add Transaction' : 'Edit Transaction'),
        backgroundColor: Colors.transparent,
        elevation: 0,
        actions: [
          IconButton(
            icon: const Icon(LucideIcons.camera),
            tooltip: 'Scan Receipt',
            onPressed: () async {
              showModalBottomSheet(
                context: context,
                builder: (ctx) => SafeArea(
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      ListTile(
                        leading: const Icon(LucideIcons.camera),
                        title: const Text('Take a Photo'),
                        onTap: () async {
                          Navigator.pop(ctx);
                          final res = await _ocrService.scanReceiptFromCamera();
                          _handleOcrResult(res);
                        },
                      ),
                      ListTile(
                        leading: const Icon(LucideIcons.image),
                        title: const Text('Choose from Gallery'),
                        onTap: () async {
                          Navigator.pop(ctx);
                          final res = await _ocrService.scanReceiptFromGallery();
                          _handleOcrResult(res);
                        },
                      ),
                    ],
                  ),
                ),
              );
            },
          )
        ],
      ),
      body: SafeArea(
        child: SingleChildScrollView(
          padding: const EdgeInsets.all(24.0),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              TextField(
                controller: amountController,
                keyboardType: const TextInputType.numberWithOptions(decimal: true, signed: false),
                textInputAction: TextInputAction.next,
                style: const TextStyle(fontSize: 32, fontWeight: FontWeight.bold, color: Color(0xFF6C63FF)),
                textAlign: TextAlign.center,
                decoration: InputDecoration(
                  hintText: '0.00',
                  hintStyle: TextStyle(color: Colors.grey.shade400),
                  prefixText: 'Rs. ',
                  prefixStyle: const TextStyle(fontSize: 24, fontWeight: FontWeight.bold, color: Colors.black87),
                  filled: true,
                  fillColor: const Color(0xFF6C63FF).withValues(alpha: 0.05),
                  contentPadding: const EdgeInsets.symmetric(vertical: 24, horizontal: 24),
                  border: OutlineInputBorder(borderRadius: BorderRadius.circular(24), borderSide: BorderSide.none),
                  focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(24), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                ),
              ),
              const SizedBox(height: 24),
              TextField(
                controller: descriptionController,
                textInputAction: TextInputAction.done,
                style: const TextStyle(fontWeight: FontWeight.w500),
                decoration: InputDecoration(
                  hintText: 'Description (Optional)',
                  prefixIcon: const Icon(LucideIcons.alignLeft, color: Colors.grey),
                  filled: true,
                  fillColor: Colors.grey.shade100,
                  contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 16),
                  border: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: BorderSide.none),
                  focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(16), borderSide: const BorderSide(color: Color(0xFF6C63FF), width: 2)),
                ),
              ),
              const SizedBox(height: 16),
              ListTile(
                title: Text(DateFormat('dd MMM yyyy').format(selectedDate)),
                trailing: const Icon(LucideIcons.calendar),
                onTap: _pickDate,
                shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
              ),
              const SizedBox(height: 12),
              
              Tooltip(
                message: 'The destination account where the money is going to.',
                child: ListTile(
                  title: Text(toWallet?.name ?? 'To Account'),
                  subtitle: toWallet != null ? Text(toWallet!.nature ?? 'CASH') : null,
                  trailing: const Icon(LucideIcons.chevronRight),
                  onTap: () => _showWalletPicker(true),
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
                ),
              ),
              const SizedBox(height: 12),
              
              Tooltip(
                message: 'The source account where the money is coming from.',
                child: ListTile(
                  title: Text(fromWallet?.name ?? 'From Account${(toWallet?.nature == "SAVINGS" || toWallet?.nature == "INCOME") ? " (Optional)" : ""}'),
                  subtitle: fromWallet != null ? Text(fromWallet!.nature ?? 'CASH') : null,
                  trailing: const Icon(LucideIcons.chevronRight),
                  onTap: () => _showWalletPicker(false),
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
                ),
              ),
              const SizedBox(height: 12),
              
              ListTile(
                title: Text(selectedCategory?.name ?? 'Select Category (Optional)'),
                trailing: const Icon(LucideIcons.chevronRight),
                onTap: _showCategoryPicker,
                shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
              ),
              const SizedBox(height: 12),
              
              if (toWallet?.nature == 'PAYABLES' || toWallet?.nature == 'LOAN') ...[
                ListTile(
                  title: Text(dueDate == null ? 'Set Due Date (Optional)' : 'Due Date: ${DateFormat('dd MMM yyyy').format(dueDate!)}'),
                  trailing: const Icon(LucideIcons.calendar),
                  onTap: () async {
                    final picked = await showDatePicker(
                      context: context,
                      initialDate: dueDate ?? DateTime.now(),
                      firstDate: DateTime.now().subtract(const Duration(days: 30)),
                      lastDate: DateTime.now().add(const Duration(days: 365 * 5)),
                    );
                    if (picked != null) {
                      setState(() => dueDate = picked);
                    }
                  },
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
                ),
                if (dueDate != null) ...[
                  const SizedBox(height: 8),
                  DropdownButtonFormField<String>(
                    value: alertSchedule,
                    decoration: InputDecoration(
                      labelText: 'Alert Notification',
                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                      contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
                    ),
                    items: const [
                      DropdownMenuItem(value: 'NONE', child: Text('No Alert')),
                      DropdownMenuItem(value: 'ON_DUE_DATE', child: Text('On Due Date')),
                      DropdownMenuItem(value: '1_DAY_BEFORE', child: Text('1 Day Before')),
                      DropdownMenuItem(value: '2_DAYS_BEFORE', child: Text('2 Days Before')),
                      DropdownMenuItem(value: '1_WEEK_BEFORE', child: Text('1 Week Before')),
                    ],
                    onChanged: (val) {
                      if (val != null) setState(() => alertSchedule = val);
                    },
                  ),
                  if (alertSchedule != 'NONE') ...[
                    const SizedBox(height: 8),
                    ListTile(
                      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12), side: BorderSide(color: Colors.grey.shade300)),
                      title: const Text('Alert Time'),
                      trailing: Text(alertTime.format(context), style: const TextStyle(fontWeight: FontWeight.bold)),
                      onTap: () async {
                        final time = await showTimePicker(
                          context: context,
                          initialTime: alertTime,
                        );
                        if (time != null) {
                          setState(() => alertTime = time);
                        }
                      },
                    ),
                  ],
                ],
                const SizedBox(height: 12),
              ],
              
              // Line Items Section
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  const Text('Items', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
                  TextButton.icon(
                    onPressed: _addLineItem,
                    icon: const Icon(LucideIcons.plus, size: 16),
                    label: const Text('Add Item'),
                  )
                ],
              ),
              if (lineItems.isNotEmpty)
                Container(
                  decoration: BoxDecoration(border: Border.all(color: Colors.grey.shade300), borderRadius: BorderRadius.circular(12)),
                  child: ListView.separated(
                    shrinkWrap: true,
                    physics: const NeverScrollableScrollPhysics(),
                    itemCount: lineItems.length,
                    separatorBuilder: (c, i) => const Divider(height: 1),
                    itemBuilder: (c, i) {
                      final item = lineItems[i];
                      return ListTile(
                        title: Text(item.name),
                        trailing: Row(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            Text('Rs. ${item.amount}', style: const TextStyle(fontWeight: FontWeight.bold)),
                            IconButton(
                              icon: const Icon(LucideIcons.trash2, color: Colors.red, size: 18),
                              onPressed: () => setState(() => lineItems.removeAt(i)),
                            )
                          ],
                        ),
                      );
                    },
                  ),
                ),
              const SizedBox(height: 12),

              // Attachments Section
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Text('Attachments (${base64Attachments.length}/3)', style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
                  if (base64Attachments.length < 3)
                    TextButton.icon(
                      onPressed: () {
                        showModalBottomSheet(
                          context: context,
                          builder: (ctx) => SafeArea(
                            child: Column(
                              mainAxisSize: MainAxisSize.min,
                              children: [
                                ListTile(
                                  leading: const Icon(LucideIcons.camera),
                                  title: const Text('Camera'),
                                  onTap: () {
                                    Navigator.pop(ctx);
                                    _pickImage(ImageSource.camera);
                                  },
                                ),
                                ListTile(
                                  leading: const Icon(LucideIcons.image),
                                  title: const Text('Gallery'),
                                  onTap: () {
                                    Navigator.pop(ctx);
                                    _pickImage(ImageSource.gallery);
                                  },
                                ),
                              ],
                            ),
                          ),
                        );
                      },
                      icon: const Icon(LucideIcons.paperclip, size: 16),
                      label: const Text('Attach'),
                    )
                ],
              ),
              if (existingAttachments.isNotEmpty)
                SizedBox(
                  height: 100,
                  child: ListView.builder(
                    scrollDirection: Axis.horizontal,
                    itemCount: existingAttachments.length,
                    itemBuilder: (c, i) {
                      final att = existingAttachments[i];
                      return Stack(
                        children: [
                          GestureDetector(
                            onTap: () => _openGallery(i),
                            child: Container(
                              margin: const EdgeInsets.only(right: 8, top: 8),
                              width: 80,
                              decoration: BoxDecoration(
                                borderRadius: BorderRadius.circular(8),
                                image: DecorationImage(
                                  image: _jwtToken != null 
                                    ? NetworkImage('https://app.technobeesolutions.in/api/kifi/transactions/${widget.transaction!.id}/attachments/${att.id}/content', headers: {'Authorization': 'Bearer $_jwtToken'})
                                    : const AssetImage('assets/images/placeholder.png') as ImageProvider,
                                  fit: BoxFit.cover,
                                ),
                              ),
                            ),
                          ),
                          Positioned(
                            top: 0,
                            right: 0,
                            child: GestureDetector(
                              onTap: () {
                                setState(() {
                                  deletedAttachmentIds.add(att.id);
                                  existingAttachments.removeAt(i);
                                });
                              },
                              child: Container(
                                padding: const EdgeInsets.all(2),
                                decoration: const BoxDecoration(color: Colors.red, shape: BoxShape.circle),
                                child: const Icon(LucideIcons.x, size: 12, color: Colors.white),
                              ),
                            ),
                          ),
                        ],
                      );
                    },
                  ),
                ),
              if (base64Attachments.isNotEmpty)
                SizedBox(
                  height: 100,
                  child: ListView.builder(
                    scrollDirection: Axis.horizontal,
                    itemCount: base64Attachments.length,
                    itemBuilder: (c, i) {
                      final att = base64Attachments[i];
                      return Stack(
                        children: [
                          GestureDetector(
                            onTap: () => _openGallery(existingAttachments.length + i),
                            child: Container(
                              margin: const EdgeInsets.only(right: 8, top: 8),
                              width: 80,
                              decoration: BoxDecoration(
                                borderRadius: BorderRadius.circular(8),
                                image: DecorationImage(
                                  image: MemoryImage(base64Decode(att['base64Content']!)),
                                  fit: BoxFit.cover,
                                ),
                              ),
                            ),
                          ),
                          Positioned(
                            top: 0,
                            right: 0,
                            child: GestureDetector(
                              onTap: () => setState(() => base64Attachments.removeAt(i)),
                              child: Container(
                                padding: const EdgeInsets.all(2),
                                decoration: const BoxDecoration(color: Colors.red, shape: BoxShape.circle),
                                child: const Icon(LucideIcons.x, size: 12, color: Colors.white),
                              ),
                            ),
                          ),
                        ],
                      );
                    },
                  ),
                ),
              const SizedBox(height: 24),
              if (widget.transaction == null)
                SwitchListTile(
                  title: const Text('Recurring Transaction'),
                  value: isRecurring,
                  activeColor: Theme.of(context).colorScheme.primary,
                  onChanged: (val) => setState(() => isRecurring = val),
                ),
              if (isRecurring && widget.transaction == null)
                DropdownButtonFormField<String>(
                  value: recurringFrequency,
                  decoration: InputDecoration(
                    labelText: 'Frequency',
                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                  ),
                  items: frequencies.map((f) => DropdownMenuItem(value: f, child: Text(f))).toList(),
                  onChanged: (val) {
                    if (val != null) setState(() => recurringFrequency = val);
                  },
                ),
              const SizedBox(height: 32),
              SizedBox(
                height: 56,
                child: ElevatedButton(
                  onPressed: isSaving ? null : _saveTransaction,
                  style: ElevatedButton.styleFrom(
                    shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
                  ),
                  child: isSaving
                      ? const CircularProgressIndicator()
                      : const Text('Save Transaction', style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
                ),
              ),
              const SizedBox(height: 32),
            ],
          ),
        ),
      ),
    );
  }

  void _openGallery(int index) {
    final List<ImageProvider> allImages = [];
    
    // Add existing attachments
    for (final att in existingAttachments) {
      if (_jwtToken != null) {
        allImages.add(NetworkImage('https://app.technobeesolutions.in/api/kifi/transactions/${widget.transaction!.id}/attachments/${att.id}/content', headers: {'Authorization': 'Bearer $_jwtToken'}));
      } else {
        allImages.add(const AssetImage('assets/images/placeholder.png'));
      }
    }
    
    // Add new attachments
    for (final att in base64Attachments) {
      allImages.add(MemoryImage(base64Decode(att['base64Content']!)));
    }
    
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => AttachmentGalleryScreen(
          images: allImages,
          initialIndex: index,
        ),
      ),
    );
  }
}