import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:lucide_icons_flutter/lucide_icons.dart';
import 'package:image_picker/image_picker.dart';
import 'dart:io';
import 'package:dio/dio.dart';
import '../../../core/network/dio_client.dart';
import 'package:intl/intl.dart';
import '../../../core/widgets/premium_text_field.dart';
import '../../../core/widgets/smart_search_dropdown.dart';
import '../../../core/widgets/barcode_scanner_screen.dart';
import '../../inventory/providers/products_provider.dart';
import '../../inventory/providers/product_categories_provider.dart';
import '../../inventory/providers/commodity_rates_provider.dart';
import '../../inventory/providers/inventory_items_provider.dart';
import '../../inventory/domain/product.dart';
import '../../inventory/domain/inventory_item.dart';
import '../providers/customers_provider.dart';
import '../providers/invoices_provider.dart';
import '../domain/customer.dart';
import '../domain/invoice.dart';
import '../../business/providers/business_provider.dart';
import '../../transactions/providers/providers.dart';
import '../../transactions/presentation/widgets/attachment_gallery_screen.dart';
import 'widgets/quick_add_customer_sheet.dart';
import '../../../core/utils/purity_utils.dart';
import 'invoice_details_screen.dart';

String _resolveImageUrl(String path) {
  if (path.startsWith('http://') || path.startsWith('https://')) {
    return path;
  }
  final base = DioClient().dio.options.baseUrl;
  final cleanPath = path.startsWith('/') ? path.substring(1) : path;
  if (cleanPath.startsWith('api/kifi-v2/upload/view') || cleanPath.startsWith('upload/view')) {
    return '$base/${cleanPath.replaceFirst('api/kifi-v2/', '')}';
  }
  return '$base/upload/view?path=${Uri.encodeComponent(cleanPath)}';
}

class InvoiceBuilderScreen extends ConsumerStatefulWidget {
  final Invoice? existingInvoice;
  final int? initialCustomerId;
  final List<InvoiceItem>? initialItems;

  const InvoiceBuilderScreen({
    super.key,
    this.existingInvoice,
    this.initialCustomerId,
    this.initialItems,
  });

  @override
  ConsumerState<InvoiceBuilderScreen> createState() => _InvoiceBuilderScreenState();
}

class _InvoiceBuilderScreenState extends ConsumerState<InvoiceBuilderScreen> {
  final _formKey = GlobalKey<FormState>();
  final _invoiceNumberCtrl = TextEditingController();
  final _notesCtrl = TextEditingController();
  final _amountPaidCtrl = TextEditingController();
  final _emiAmountCtrl = TextEditingController();
  final _discountCtrl = TextEditingController(text: '0.0');

  DateTime _invoiceDate = DateTime.now();
  DateTime? _dueDate;
  int? _selectedCustomerId;
  final List<InvoiceItem> _items = [];
  bool _isLoading = false;

  XFile? _invoiceFile;
  String? _invoiceUrl;

  String _paymentMethod = 'Cash';
  int? _selectedWalletId;
  DateTime? _nextPaymentDate;
  bool _isAmountPaidEdited = false;

  // EMI State
  bool _isEmi = false;
  String _emiCycle = 'MONTHLY';
  DateTime? _emiStartDate;

  @override
  void initState() {
    super.initState();
    if (widget.existingInvoice != null) {
      final inv = widget.existingInvoice!;
      _invoiceNumberCtrl.text = inv.invoiceNumber;
      _invoiceDate = inv.issueDate;
      _dueDate = inv.dueDate;
      _selectedCustomerId = inv.customerId;
      _notesCtrl.text = inv.notes ?? '';
      _items.addAll(inv.items);
      _invoiceUrl = inv.invoiceUrl;
      if (inv.discountTotal > 0) {
        _discountCtrl.text = inv.discountTotal.toStringAsFixed(2);
      }
      _amountPaidCtrl.text = inv.amountPaid > 0 ? inv.amountPaid.toStringAsFixed(2) : '';
      _selectedWalletId = inv.paymentWalletId;
      _paymentMethod = inv.paymentMethod ?? 'Cash';
      _nextPaymentDate = inv.nextPaymentDate;
      _isAmountPaidEdited = inv.amountPaid > 0;
      _isEmi = inv.isEmi;
      _emiCycle = inv.emiCycle ?? 'MONTHLY';
      _emiStartDate = inv.emiStartDate;
      if (inv.emiAmount != null) {
        _emiAmountCtrl.text = inv.emiAmount!.toStringAsFixed(2);
      }
    } else {
      _invoiceNumberCtrl.text = 'INV-${DateTime.now().millisecondsSinceEpoch.toString().substring(7)}';
      _selectedCustomerId = widget.initialCustomerId;
      _dueDate = DateTime.now().add(const Duration(days: 30));
      _emiStartDate = DateTime.now().add(const Duration(days: 30));
      if (widget.initialItems != null) {
        _items.addAll(widget.initialItems!);
      }
    }
  }

  @override
  void dispose() {
    _invoiceNumberCtrl.dispose();
    _notesCtrl.dispose();
    _amountPaidCtrl.dispose();
    _emiAmountCtrl.dispose();
    _discountCtrl.dispose();
    super.dispose();
  }

  Future<void> _pickInvoiceFile() async {
    try {
      final picker = ImagePicker();
      final picked = await picker.pickImage(
        source: ImageSource.gallery,
        imageQuality: 80,
      );
      if (picked != null) {
        setState(() {
          _invoiceFile = picked;
          _isLoading = true;
        });

        final bytes = await picked.readAsBytes();
        final formData = FormData.fromMap({
          'file': MultipartFile.fromBytes(
            bytes,
            filename: picked.name.isNotEmpty ? picked.name : 'invoice_${DateTime.now().millisecondsSinceEpoch}.jpg',
          ),
          'type': 'SALES_INVOICE',
        });

        final uploadResp = await DioClient().dio.post(
          '/upload',
          data: formData,
        );

        if (uploadResp.statusCode == 200) {
          setState(() {
            _invoiceUrl = uploadResp.data['url'];
          });
        }
      }
    } catch (e) {
      debugPrint('Error uploading sales invoice attachment: $e');
    } finally {
      if (mounted) setState(() => _isLoading = false);
    }
  }

  void _showQuickAddCustomer() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (_) => const QuickAddCustomerSheet(),
    ).then((result) {
      if (result != null) {
        if (result is Customer && result.id != null) {
          setState(() => _selectedCustomerId = result.id);
        } else {
          ref.refresh(customersProvider);
        }
      }
    });
  }

  void _openAddItemSheet({int? editIndex}) {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (_) => _AddSalesItemSheet(
        initialItem: editIndex != null ? _items[editIndex] : null,
        onItemAdded: (item) {
          setState(() {
            if (editIndex != null) {
              _items[editIndex] = item;
            } else {
              _items.add(item);
            }
          });
        },
      ),
    );
  }

  Future<void> _scanBarcode() async {
    final scannedCode = await Navigator.push<String>(
      context,
      MaterialPageRoute(builder: (_) => const BarcodeScannerScreen()),
    );
    if (scannedCode != null && scannedCode.isNotEmpty) {
      final inventoryItems = ref.read(inventoryItemsProvider).value ?? [];
      final products = ref.read(productsProvider).value ?? [];
      final categories = ref.read(productCategoriesProvider).value ?? [];
      final commodityRates = ref.read(commodityRatesProvider).value ?? [];

      // Check inventory item by HUID or SKU or Barcode
      final invItem = inventoryItems.where((i) => 
        (i.huid != null && i.huid!.toUpperCase() == scannedCode.toUpperCase()) ||
        (i.sku != null && i.sku!.toUpperCase() == scannedCode.toUpperCase())
      ).firstOrNull;

      Product? matchedProduct;
      if (invItem != null) {
        matchedProduct = products.where((p) => p.id == invItem.productId).firstOrNull;
      } else {
        matchedProduct = products.where((p) => 
          (p.barcode != null && p.barcode == scannedCode) ||
          (p.sku != null && p.sku!.toUpperCase() == scannedCode.toUpperCase())
        ).firstOrNull;
      }

      if (matchedProduct != null) {
        final cat = categories.where((c) => c.id == matchedProduct!.categoryId).firstOrNull;
        double commodityRate = 0.0;
        if (cat?.commodityCode != null) {
          final match = commodityRates.where((r) => r.commodityCode.toUpperCase() == cat!.commodityCode!.toUpperCase()).firstOrNull;
          if (match != null) commodityRate = match.rate;
        }
        final purity = resolvePurity(categoryPurity: cat?.purityFactor, productPurity: matchedProduct.purityFactor);
        final effectiveRate = commodityRate > 0 ? (commodityRate * purity) : (matchedProduct.sellingPrice ?? 0.0);
        final weight = invItem?.grossWeight ?? 1.0;
        final makingCharge = invItem?.makingCharges ?? matchedProduct.makingCharges ?? cat?.defaultMakingCharge ?? 0.0;
        final makingType = invItem?.makingChargeType ?? matchedProduct.makingChargesType ?? cat?.makingChargeType ?? 'PER_GRAM';
        final metalAmount = weight * effectiveRate;

        double makingAmt = 0.0;
        if (makingType == 'PERCENTAGE') {
          makingAmt = metalAmount * (makingCharge / 100.0);
        } else if (makingType == 'PER_PIECE') {
          makingAmt = makingCharge;
        } else {
          makingAmt = weight * makingCharge;
        }

        final gstRate = matchedProduct.gstRate ?? (cat?.defaultGst ?? 3.0);
        final taxable = metalAmount + makingAmt;
        final taxAmount = (taxable * gstRate) / 100.0;
        final total = taxable + taxAmount;

        final item = InvoiceItem(
          productId: matchedProduct.id,
          inventoryItemId: invItem?.id,
          productName: matchedProduct.name,
          categoryName: cat?.name,
          commodityCode: cat?.commodityCode,
          hsnCode: cat?.defaultHsn ?? matchedProduct.hsnCode,
          sku: invItem?.sku ?? matchedProduct.sku,
          huid: invItem?.huid,
          description: matchedProduct.name,
          quantity: 1.0,
          weight: weight,
          unitPrice: effectiveRate,
          makingCharge: makingCharge,
          makingChargesType: makingType,
          taxRate: gstRate,
          total: total,
        );

        setState(() => _items.add(item));
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text('Added ${matchedProduct.name} via barcode scan!'), backgroundColor: Colors.green),
          );
        }
      } else {
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text('No item found with barcode/HUID: $scannedCode'), backgroundColor: Colors.orange),
          );
        }
      }
    }
  }

  Future<void> _saveInvoice() async {
    if (!_formKey.currentState!.validate()) return;
    if (_items.isEmpty) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('Please add at least one line item')),
      );
      return;
    }

    setState(() => _isLoading = true);
    try {
      String? finalInvoiceUrl = _invoiceUrl;

      if (_invoiceFile != null && finalInvoiceUrl == null) {
        final bytes = await _invoiceFile!.readAsBytes();
        final formData = FormData.fromMap({
          'file': MultipartFile.fromBytes(
            bytes,
            filename: _invoiceFile!.name.isNotEmpty ? _invoiceFile!.name : 'invoice.jpg',
          ),
          'type': 'SALES_INVOICE',
        });
        final uploadResp = await DioClient().dio.post(
          '/upload',
          data: formData,
        );
        if (uploadResp.statusCode == 200) {
          finalInvoiceUrl = uploadResp.data['url'];
        }
      }

      final products = ref.read(productsProvider).value ?? [];
      final businessStateId = ref.read(businessProfileProvider).value?.stateId;
      final customers = ref.read(customersProvider).value ?? [];
      final customer = _selectedCustomerId == null 
          ? null 
          : customers.where((c) => c.id == _selectedCustomerId).firstOrNull;
      
      final isSameState = businessStateId != null && customer?.stateId != null && businessStateId == customer!.stateId;

      double subtotal = 0;
      double totalCgst = 0;
      double totalSgst = 0;
      double totalIgst = 0;
      double totalTax = 0;
      double totalMaking = 0;
      double totalDiscount = 0;
      double grandTotal = 0;

      final List<InvoiceItem> processedItems = [];

      for (var item in _items) {
        final product = products.where((p) => p.id == item.productId).firstOrNull;
        final gstRate = item.taxRate > 0 ? item.taxRate : (product?.gstRate ?? 0.0);

        final weight = item.weight ?? item.quantity;
        final metalAmount = weight * item.unitPrice;

        double makingChargeAmt = 0.0;
        if (item.makingChargesType == 'PERCENTAGE') {
          makingChargeAmt = metalAmount * (item.makingCharge / 100.0);
        } else if (item.makingChargesType == 'PER_PIECE') {
          makingChargeAmt = item.makingCharge;
        } else {
          makingChargeAmt = weight * item.makingCharge;
        }

        final taxableAmount = metalAmount + makingChargeAmt + item.otherCharges - item.discount;
        final taxAmount = (taxableAmount * gstRate) / 100.0;

        double cgst = 0;
        double sgst = 0;
        double igst = 0;

        if (isSameState) {
          cgst = taxAmount / 2.0;
          sgst = taxAmount / 2.0;
          totalCgst += cgst;
          totalSgst += sgst;
        } else {
          igst = taxAmount;
          totalIgst += igst;
        }

        final lineTotal = taxableAmount + taxAmount;

        subtotal += metalAmount;
        totalMaking += makingChargeAmt;
        totalTax += taxAmount;

        processedItems.add(item.copyWith(
          taxRate: gstRate,
          cgst: cgst,
          sgst: sgst,
          igst: igst,
          total: lineTotal,
        ));
      }

      final invoiceDiscount = double.tryParse(_discountCtrl.text) ?? 0.0;
      totalDiscount = double.parse(invoiceDiscount.toStringAsFixed(2));
      final rawGrandTotal = (subtotal + totalMaking - invoiceDiscount).clamp(0.0, double.infinity) + totalTax;
      grandTotal = double.parse(rawGrandTotal.toStringAsFixed(2));

      final amountPaid = double.tryParse(_amountPaidCtrl.text) ?? (_isAmountPaidEdited ? 0.0 : grandTotal);
      final validAmountPaid = double.parse((amountPaid > grandTotal ? grandTotal : amountPaid).toStringAsFixed(2));
      final balanceDue = double.parse((grandTotal - validAmountPaid).clamp(0.0, double.infinity).toStringAsFixed(2));
      final isFullyPaid = balanceDue.abs() < 0.01 || validAmountPaid >= grandTotal - 0.01;
      final determinedStatus = isFullyPaid ? 'PAID' : (validAmountPaid > 0.01 ? 'PARTIAL' : 'DRAFT');

      final invoice = Invoice(
        id: widget.existingInvoice?.id,
        customerId: _selectedCustomerId,
        invoiceNumber: _invoiceNumberCtrl.text.trim(),
        issueDate: _invoiceDate,
        dueDate: _dueDate,
        subtotal: double.parse(subtotal.toStringAsFixed(2)),
        taxTotal: double.parse(totalTax.toStringAsFixed(2)),
        cgstTotal: double.parse(totalCgst.toStringAsFixed(2)),
        sgstTotal: double.parse(totalSgst.toStringAsFixed(2)),
        igstTotal: double.parse(totalIgst.toStringAsFixed(2)),
        discountTotal: totalDiscount,
        totalAmount: grandTotal,
        amountPaid: validAmountPaid,
        paymentMethod: validAmountPaid > 0 ? _paymentMethod : null,
        paymentWalletId: validAmountPaid > 0
            ? (_selectedWalletId ??
                ref.read(walletProvider).value?.where((w) => w.nature == 'CASH' || w.nature == 'SAVINGS').firstOrNull?.id)
            : null,
        nextPaymentDate: balanceDue > 0.01 ? (_nextPaymentDate ?? DateTime.now().add(const Duration(days: 30))) : null,
        status: widget.existingInvoice != null
            ? (isFullyPaid ? 'PAID' : (validAmountPaid > 0.01 ? 'PARTIAL' : widget.existingInvoice!.status))
            : determinedStatus,
        notes: _notesCtrl.text.trim().isEmpty ? null : _notesCtrl.text.trim(),
        invoiceUrl: finalInvoiceUrl,
        isEmi: _isEmi,
        emiAmount: _isEmi && _emiAmountCtrl.text.isNotEmpty ? double.tryParse(_emiAmountCtrl.text) : null,
        emiCycle: _isEmi ? _emiCycle : null,
        emiStartDate: _isEmi ? (_emiStartDate ?? DateTime.now().add(const Duration(days: 30))) : null,
        items: processedItems,
      );

      Invoice? savedInvoice;
      if (widget.existingInvoice == null) {
        savedInvoice = await ref.read(invoicesProvider.notifier).createInvoice(invoice);
      } else {
        final resp = await DioClient().dio.put(
          '/invoices/${widget.existingInvoice!.id}',
          data: invoice.toJson(),
        );
        if (resp.statusCode == 200) {
          savedInvoice = Invoice.fromJson(resp.data);
          ref.refresh(invoicesProvider);
        }
      }

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Sales Invoice saved successfully!'), backgroundColor: Colors.green),
        );
        if (savedInvoice != null) {
          Navigator.pushReplacement(
            context,
            MaterialPageRoute(
              builder: (_) => InvoiceDetailsScreen(invoice: savedInvoice!),
            ),
          );
        } else {
          Navigator.pop(context);
        }
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Error saving invoice: $e'), backgroundColor: Colors.red),
        );
      }
    } finally {
      if (mounted) setState(() => _isLoading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final customersState = ref.watch(customersProvider);
    final isDark = Theme.of(context).brightness == Brightness.dark;

    return Scaffold(
      appBar: AppBar(
        title: Text(
          widget.existingInvoice == null
              ? 'New Sales Invoice'
              : 'Edit Invoice ${_invoiceNumberCtrl.text}',
          style: const TextStyle(fontWeight: FontWeight.bold),
        ),
        actions: [
          IconButton(
            icon: const Icon(LucideIcons.qrCode),
            tooltip: 'Scan Barcode/HUID',
            onPressed: _scanBarcode,
          ),
          if (_isLoading)
            const Padding(
              padding: EdgeInsets.all(16.0),
              child: SizedBox(
                width: 20,
                height: 20,
                child: CircularProgressIndicator(strokeWidth: 2),
              ),
            )
          else
            TextButton.icon(
              onPressed: _saveInvoice,
              icon: const Icon(LucideIcons.check, size: 18),
              label: const Text('Save', style: TextStyle(fontWeight: FontWeight.bold)),
            ),
        ],
      ),
      body: GestureDetector(
        onTap: () => FocusScope.of(context).unfocus(),
        behavior: HitTestBehavior.translucent,
        child: Form(
          key: _formKey,
          child: ListView(
            keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
            padding: const EdgeInsets.all(16.0),
            children: [
            // Customer Selection Row + Quick Add
            Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Expanded(
                  child: customersState.when(
                    data: (customers) => SmartSearchDropdown<Customer>(
                      labelText: 'Customer *',
                      hintText: 'Search Customer by Name / Phone / GSTIN / City',
                      value: customers.where((c) => c.id == _selectedCustomerId).firstOrNull,
                      items: customers,
                      itemAsString: (c) => c.name,
                      filterFn: (c, query) {
                        final q = query.toLowerCase();
                        return c.name.toLowerCase().contains(q) ||
                            (c.phone != null && c.phone!.contains(q)) ||
                            (c.email != null && c.email!.toLowerCase().contains(q)) ||
                            (c.gstin != null && c.gstin!.toLowerCase().contains(q)) ||
                            (c.address != null && c.address!.toLowerCase().contains(q));
                      },
                      itemBuilder: (context, c) {
                        return Padding(
                          padding: const EdgeInsets.symmetric(horizontal: 14.0, vertical: 10.0),
                          child: Row(
                            crossAxisAlignment: CrossAxisAlignment.start,
                            children: [
                              CircleAvatar(
                                radius: 18,
                                backgroundColor: Colors.blue.withValues(alpha: 0.15),
                                child: Text(
                                  c.name.isNotEmpty ? c.name[0].toUpperCase() : 'C',
                                  style: const TextStyle(fontWeight: FontWeight.bold, color: Colors.blue, fontSize: 14),
                                ),
                              ),
                              const SizedBox(width: 12),
                              Expanded(
                                child: Column(
                                  crossAxisAlignment: CrossAxisAlignment.start,
                                  children: [
                                    Text(
                                      c.name,
                                      style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 14),
                                    ),
                                    const SizedBox(height: 3),
                                    Wrap(
                                      spacing: 6,
                                      runSpacing: 3,
                                      children: [
                                        if (c.phone != null && c.phone!.isNotEmpty)
                                          _buildSmallBadge(c.phone!, Colors.teal),
                                        if (c.address != null && c.address!.isNotEmpty)
                                          _buildSmallBadge(c.address!, Colors.purple),
                                        if (c.gstin != null && c.gstin!.isNotEmpty)
                                          _buildSmallBadge('GST: ${c.gstin}', Colors.indigo),
                                      ],
                                    ),
                                  ],
                                ),
                              ),
                            ],
                          ),
                        );
                      },
                      onChanged: (val) {
                        setState(() {
                          _selectedCustomerId = val?.id;
                        });
                      },
                    ),
                    loading: () => const Center(child: CircularProgressIndicator()),
                    error: (e, _) => Text('Error loading customers: $e'),
                  ),
                ),
                const SizedBox(width: 8),
                Padding(
                  padding: const EdgeInsets.only(top: 4.0),
                  child: IconButton.filledTonal(
                    onPressed: _showQuickAddCustomer,
                    icon: const Icon(LucideIcons.userPlus, size: 20),
                    tooltip: 'Quick Add Customer',
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),

            PremiumTextField(
              controller: _invoiceNumberCtrl,
              labelText: 'Invoice Number *',
              prefixIcon: const Icon(LucideIcons.fileText),
              validator: (val) => val == null || val.isEmpty ? 'Required' : null,
            ),
            const SizedBox(height: 16),
            InkWell(
              onTap: () async {
                final picked = await showDatePicker(
                  context: context,
                  initialDate: _invoiceDate,
                  firstDate: DateTime(2000),
                  lastDate: DateTime(2100),
                );
                if (picked != null) {
                  setState(() => _invoiceDate = picked);
                }
              },
              child: InputDecorator(
                decoration: InputDecoration(
                  labelText: 'Invoice Date',
                  prefixIcon: const Icon(LucideIcons.calendar),
                  border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                ),
                child: Text(
                  DateFormat('dd MMM yyyy').format(_invoiceDate),
                  style: const TextStyle(fontWeight: FontWeight.w600, fontSize: 14),
                ),
              ),
            ),
            const SizedBox(height: 24),

            // Items Section Header with Barcode + Add Item
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text(
                  'Invoice Items (${_items.length})',
                  style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold),
                ),
                Row(
                  children: [
                    IconButton.filledTonal(
                      onPressed: _scanBarcode,
                      icon: const Icon(LucideIcons.qrCode, size: 18),
                      tooltip: 'Scan Barcode',
                    ),
                    const SizedBox(width: 8),
                    FilledButton.tonalIcon(
                      onPressed: () => _openAddItemSheet(),
                      icon: const Icon(LucideIcons.plus, size: 16),
                      label: const Text('Add Item'),
                    ),
                  ],
                ),
              ],
            ),
            const SizedBox(height: 12),

            // Items List
            if (_items.isEmpty)
              Container(
                padding: const EdgeInsets.all(32),
                decoration: BoxDecoration(
                  color: isDark ? const Color(0xFF1E293B) : Colors.grey.shade100,
                  borderRadius: BorderRadius.circular(16),
                  border: Border.all(color: Colors.grey.withValues(alpha: 0.2)),
                ),
                child: Column(
                  children: [
                    Icon(LucideIcons.shoppingBag, size: 48, color: Colors.grey.shade400),
                    const SizedBox(height: 12),
                    Text(
                      'No items added yet',
                      style: TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: Colors.grey.shade600),
                    ),
                    const SizedBox(height: 4),
                    Text(
                      'Tap "Add Item" or scan a barcode/HUID to add jewellery',
                      style: TextStyle(fontSize: 12, color: Colors.grey.shade500),
                    ),
                  ],
                ),
              )
            else
              ..._items.asMap().entries.map((entry) {
                final idx = entry.key;
                final item = entry.value;
                return _buildSalesItemCard(item, idx, isDark);
              }),

            const SizedBox(height: 20),

            // Invoice Discount Input Field before Summary
            PremiumTextField(
              controller: _discountCtrl,
              labelText: 'Invoice Discount (₹)',
              prefixIcon: const Icon(LucideIcons.tag, color: Colors.red),
              keyboardType: const TextInputType.numberWithOptions(decimal: true),
              onChanged: (_) => setState(() {}),
            ),

            const SizedBox(height: 20),

            // Grand Total & Tax Summary Box
            _buildTotalsSummaryCard(isDark),

            const SizedBox(height: 24),

            // Payment / Settlement Details (Full Partial Payment & EMI Support)
            _buildPaymentSection(isDark),

            const SizedBox(height: 24),

            // Notes & Remarks
            PremiumTextField(
              controller: _notesCtrl,
              labelText: 'Notes & Terms',
              maxLines: 3,
              prefixIcon: const Icon(LucideIcons.alignLeft),
            ),
            const SizedBox(height: 24),

            // Attachments
            Text(
              'Attached Invoice / Documents',
              style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold),
            ),
            const SizedBox(height: 8),
            if (_invoiceFile != null)
              ListTile(
                leading: const Icon(LucideIcons.image, color: Colors.blue),
                title: Text(_invoiceFile!.name),
                subtitle: const Text('Tap to view image', style: TextStyle(fontSize: 12, color: Colors.blue)),
                onTap: () {
                  Navigator.push(
                    context,
                    MaterialPageRoute(
                      builder: (_) => AttachmentGalleryScreen(
                        images: [kIsWeb ? NetworkImage(_invoiceFile!.path) : FileImage(File(_invoiceFile!.path))],
                        initialIndex: 0,
                      ),
                    ),
                  );
                },
                trailing: IconButton(
                  icon: const Icon(LucideIcons.x),
                  onPressed: () => setState(() => _invoiceFile = null),
                ),
              )
            else if (_invoiceUrl != null && _invoiceUrl!.isNotEmpty)
              ListTile(
                leading: const Icon(LucideIcons.image, color: Colors.blue),
                title: const Text('View Attached Invoice'),
                subtitle: const Text('Tap to view full image', style: TextStyle(fontSize: 12, color: Colors.blue)),
                onTap: () {
                  Navigator.push(
                    context,
                    MaterialPageRoute(
                      builder: (_) => AttachmentGalleryScreen(
                        images: [NetworkImage(_resolveImageUrl(_invoiceUrl!))],
                        initialIndex: 0,
                      ),
                    ),
                  );
                },
                trailing: IconButton(
                  icon: const Icon(LucideIcons.x),
                  onPressed: () => setState(() => _invoiceUrl = null),
                ),
              )
            else
              OutlinedButton.icon(
                onPressed: _pickInvoiceFile,
                icon: const Icon(LucideIcons.paperclip),
                label: const Text('Attach Sales Bill / Slip'),
                style: OutlinedButton.styleFrom(
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
                  padding: const EdgeInsets.symmetric(vertical: 14),
                ),
              ),
            const SizedBox(height: 40),
          ],
        ),
      ),
    ),
  );
  }

  Widget _buildSalesItemCard(InvoiceItem item, int index, bool isDark) {
    final weight = item.weight ?? item.quantity;
    final metalAmount = weight * item.unitPrice;
    
    double makingChargeAmt = 0.0;
    if (item.makingChargesType == 'PERCENTAGE') {
      makingChargeAmt = metalAmount * (item.makingCharge / 100.0);
    } else if (item.makingChargesType == 'PER_PIECE') {
      makingChargeAmt = item.makingCharge;
    } else {
      makingChargeAmt = weight * item.makingCharge;
    }

    final calculatedTotal = item.total > 0 ? item.total : (metalAmount + makingChargeAmt + item.otherCharges - item.discount);

    return Container(
      margin: const EdgeInsets.only(bottom: 12),
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: isDark ? const Color(0xFF1E293B) : Colors.white,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: isDark ? Colors.white12 : Colors.grey.shade200),
        boxShadow: [
          BoxShadow(
            color: Colors.black.withValues(alpha: isDark ? 0.2 : 0.04),
            blurRadius: 10,
            offset: const Offset(0, 4),
          ),
        ],
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              if (item.photoUrl != null && item.photoUrl!.isNotEmpty)
                Container(
                  width: 48,
                  height: 48,
                  margin: const EdgeInsets.only(right: 12),
                  decoration: BoxDecoration(
                    borderRadius: BorderRadius.circular(8),
                    image: DecorationImage(
                      image: NetworkImage(_resolveImageUrl(item.photoUrl!)),
                      fit: BoxFit.cover,
                    ),
                  ),
                ),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      item.productName ?? item.description ?? 'Item #${index + 1}',
                      style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16),
                    ),
                    const SizedBox(height: 4),
                    Wrap(
                      spacing: 6,
                      runSpacing: 4,
                      children: [
                        if (item.categoryName != null && item.categoryName!.isNotEmpty)
                          _buildSmallBadge(item.categoryName!, const Color(0xFFD4AF37)),
                        if (item.sku != null && item.sku!.isNotEmpty)
                          _buildSmallBadge('SKU: ${item.sku}', Colors.blue),
                        if (item.huid != null && item.huid!.isNotEmpty)
                          _buildSmallBadge('HUID: ${item.huid}', Colors.purple),
                        if (item.hsnCode != null && item.hsnCode!.isNotEmpty)
                          _buildSmallBadge('HSN: ${item.hsnCode}', Colors.grey),
                      ],
                    ),
                  ],
                ),
              ),
              IconButton(
                icon: const Icon(LucideIcons.edit2, size: 18, color: Colors.blue),
                tooltip: 'Edit Item',
                onPressed: () => _openAddItemSheet(editIndex: index),
              ),
              IconButton(
                icon: const Icon(LucideIcons.trash2, size: 18, color: Colors.red),
                tooltip: 'Remove Item',
                onPressed: () {
                  setState(() => _items.removeAt(index));
                },
              ),
            ],
          ),
          const Divider(height: 20),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                'Metal: ${weight.toStringAsFixed(3)}g × ₹${item.unitPrice.toStringAsFixed(2)}',
                style: TextStyle(fontSize: 13, color: Colors.grey.shade600),
              ),
              Text(
                '₹${metalAmount.toStringAsFixed(2)}',
                style: const TextStyle(fontWeight: FontWeight.w600, fontSize: 13),
              ),
            ],
          ),
          const SizedBox(height: 4),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                'Making Charges (${item.makingChargesType == 'PERCENTAGE' ? '${item.makingCharge}%' : (item.makingChargesType == 'PER_PIECE' ? '₹${item.makingCharge}/pc' : '₹${item.makingCharge}/g')}):',
                style: TextStyle(fontSize: 13, color: Colors.grey.shade600),
              ),
              Text(
                '₹${makingChargeAmt.toStringAsFixed(2)}',
                style: const TextStyle(fontWeight: FontWeight.w600, fontSize: 13, color: Colors.indigo),
              ),
            ],
          ),
          if (item.taxRate > 0) ...[
            const SizedBox(height: 4),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text(
                  'GST (${item.taxRate.toStringAsFixed(1)}%):',
                  style: TextStyle(fontSize: 12, color: Colors.grey.shade500),
                ),
                Text(
                  '+ ₹${((metalAmount + makingChargeAmt) * (item.taxRate / 100.0)).toStringAsFixed(2)}',
                  style: TextStyle(fontSize: 12, color: Colors.grey.shade600),
                ),
              ],
            ),
          ],
          const SizedBox(height: 8),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Text('Item Total:', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 14)),
              Text(
                '₹${calculatedTotal.toStringAsFixed(2)}',
                style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16, color: Colors.green),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget _buildSmallBadge(String text, Color color) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.12),
        borderRadius: BorderRadius.circular(6),
        border: Border.all(color: color.withValues(alpha: 0.3), width: 0.5),
      ),
      child: Text(
        text,
        style: TextStyle(fontSize: 10, fontWeight: FontWeight.bold, color: color),
      ),
    );
  }

  Widget _buildTotalsSummaryCard(bool isDark) {
    final products = ref.watch(productsProvider).value ?? [];
    final businessStateId = ref.watch(businessProfileProvider).value?.stateId;
    final customers = ref.watch(customersProvider).value ?? [];
    final customer = _selectedCustomerId == null 
        ? null 
        : customers.where((c) => c.id == _selectedCustomerId).firstOrNull;
    
    final discountAmount = double.tryParse(_discountCtrl.text) ?? 0.0;
    final isSameState = businessStateId != null && customer?.stateId != null && businessStateId == customer!.stateId;

    double metalSubtotal = 0;
    double makingChargesTotal = 0;
    double rawTaxableTotal = 0;
    double taxTotal = 0;

    for (var item in _items) {
      final product = products.where((p) => p.id == item.productId).firstOrNull;
      final gstRate = item.taxRate > 0 ? item.taxRate : (product?.gstRate ?? 3.0);
      final weight = item.weight ?? item.quantity;
      final metalAmt = weight * item.unitPrice;

      double makingAmt = 0.0;
      if (item.makingChargesType == 'PERCENTAGE') {
        makingAmt = metalAmt * (item.makingCharge / 100.0);
      } else if (item.makingChargesType == 'PER_PIECE') {
        makingAmt = item.makingCharge;
      } else {
        makingAmt = weight * item.makingCharge;
      }

      metalSubtotal += metalAmt;
      makingChargesTotal += makingAmt;
      rawTaxableTotal += (metalAmt + makingAmt + item.otherCharges);
    }

    final effectiveTaxable = (rawTaxableTotal - discountAmount).clamp(0.0, double.infinity);
    final avgGstRate = _items.isNotEmpty
        ? (_items.map((i) => i.taxRate > 0 ? i.taxRate : 3.0).reduce((a, b) => a + b) / _items.length)
        : 3.0;
    taxTotal = (effectiveTaxable * avgGstRate) / 100.0;
    final grandTotal = effectiveTaxable + taxTotal;

    return Container(
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: isDark ? const Color(0xFF1E293B) : Colors.white,
        borderRadius: BorderRadius.circular(20),
        border: Border.all(color: isDark ? Colors.white12 : Colors.grey.shade200),
        boxShadow: [
          BoxShadow(
            color: Colors.black.withValues(alpha: isDark ? 0.2 : 0.05),
            blurRadius: 15,
            offset: const Offset(0, 5),
          ),
        ],
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const Text('INVOICE SUMMARY', style: TextStyle(fontSize: 12, fontWeight: FontWeight.bold, letterSpacing: 0.8, color: Colors.grey)),
          const SizedBox(height: 14),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Text('Metal Subtotal:'),
              Text('₹${metalSubtotal.toStringAsFixed(2)}', style: const TextStyle(fontWeight: FontWeight.w600)),
            ],
          ),
          const SizedBox(height: 8),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Text('Making Charges:'),
              Text('₹${makingChargesTotal.toStringAsFixed(2)}', style: const TextStyle(fontWeight: FontWeight.w600)),
            ],
          ),
          if (discountAmount > 0) ...[
            const SizedBox(height: 8),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                const Text('Discount:', style: TextStyle(color: Colors.red, fontWeight: FontWeight.w600)),
                Text('- ₹${discountAmount.toStringAsFixed(2)}', style: const TextStyle(fontWeight: FontWeight.bold, color: Colors.red)),
              ],
            ),
          ],
          const SizedBox(height: 8),
          if (isSameState) ...[
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text('CGST (${(taxTotal > 0 ? '1.5%' : '0%')}):', style: TextStyle(color: Colors.grey.shade600)),
                Text('₹${(taxTotal / 2.0).toStringAsFixed(2)}'),
              ],
            ),
            const SizedBox(height: 6),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text('SGST (${(taxTotal > 0 ? '1.5%' : '0%')}):', style: TextStyle(color: Colors.grey.shade600)),
                Text('₹${(taxTotal / 2.0).toStringAsFixed(2)}'),
              ],
            ),
          ] else ...[
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text('IGST (${(taxTotal > 0 ? '3.0%' : '0%')}):', style: TextStyle(color: Colors.grey.shade600)),
                Text('₹${taxTotal.toStringAsFixed(2)}'),
              ],
            ),
          ],
          const Divider(height: 24),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Text('Grand Total:', style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
              Text(
                '₹${grandTotal.toStringAsFixed(2)}',
                style: const TextStyle(fontSize: 22, fontWeight: FontWeight.bold, color: Colors.green),
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget _buildPaymentSection(bool isDark) {
    final wallets = ref.watch(walletProvider).value ?? [];
    final activeWallets = wallets.where((w) => w.nature == 'CASH' || w.nature == 'SAVINGS').toList();

    // Compute grand total for live balance due
    final products = ref.watch(productsProvider).value ?? [];
    final discountAmount = double.tryParse(_discountCtrl.text) ?? 0.0;
    double rawTaxable = 0;
    for (var item in _items) {
      final weight = item.weight ?? item.quantity;
      final metalAmt = weight * item.unitPrice;
      double makingAmt = 0.0;
      if (item.makingChargesType == 'PERCENTAGE') {
        makingAmt = metalAmt * (item.makingCharge / 100.0);
      } else if (item.makingChargesType == 'PER_PIECE') {
        makingAmt = item.makingCharge;
      } else {
        makingAmt = weight * item.makingCharge;
      }
      rawTaxable += (metalAmt + makingAmt + item.otherCharges);
    }
    final effectiveTaxable = (rawTaxable - discountAmount).clamp(0.0, double.infinity);
    final avgGst = _items.isNotEmpty
        ? (_items.map((i) => i.taxRate > 0 ? i.taxRate : 3.0).reduce((a, b) => a + b) / _items.length)
        : 3.0;
    final grandTotal = effectiveTaxable + (effectiveTaxable * avgGst / 100.0);

    // If user has not manually changed amount paid and grandTotal > 0, auto-track grand total
    if (!_isAmountPaidEdited && grandTotal > 0 && _amountPaidCtrl.text != grandTotal.toStringAsFixed(2)) {
      _amountPaidCtrl.text = grandTotal.toStringAsFixed(2);
    }

    final enteredAmount = double.tryParse(_amountPaidCtrl.text) ?? (_isAmountPaidEdited ? 0.0 : grandTotal);
    final amountPaid = enteredAmount > grandTotal ? grandTotal : enteredAmount;
    final balanceDue = grandTotal - amountPaid;

    Widget? statusBadge;
    if (grandTotal > 0 && (_isAmountPaidEdited || _amountPaidCtrl.text.isNotEmpty)) {
      if (amountPaid >= grandTotal) {
        statusBadge = Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
          decoration: BoxDecoration(
            color: Colors.green.withValues(alpha: 0.15),
            borderRadius: BorderRadius.circular(6),
          ),
          child: const Text(
            'Fully Paid',
            style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold, color: Colors.green),
          ),
        );
      } else if (amountPaid > 0) {
        statusBadge = Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
          decoration: BoxDecoration(
            color: Colors.orange.withValues(alpha: 0.15),
            borderRadius: BorderRadius.circular(6),
          ),
          child: const Text(
            'Partial Payment',
            style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold, color: Colors.orange),
          ),
        );
      } else {
        statusBadge = Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
          decoration: BoxDecoration(
            color: Colors.red.withValues(alpha: 0.15),
            borderRadius: BorderRadius.circular(6),
          ),
          child: const Text(
            'Unpaid',
            style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold, color: Colors.red),
          ),
        );
      }
    }

    return Container(
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: isDark ? const Color(0xFF1E293B) : Colors.white,
        borderRadius: BorderRadius.circular(20),
        border: Border.all(color: isDark ? Colors.white12 : Colors.grey.shade200),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Text('PAYMENT & SETTLEMENT', style: TextStyle(fontSize: 12, fontWeight: FontWeight.bold, letterSpacing: 0.8, color: Colors.grey)),
              if (statusBadge != null)
                Flexible(child: statusBadge),
            ],
          ),
          const SizedBox(height: 16),
          Row(
            children: [
              Expanded(
                child: PremiumTextField(
                  controller: _amountPaidCtrl,
                  labelText: 'Amount Received (₹)',
                  keyboardType: const TextInputType.numberWithOptions(decimal: true),
                  prefixIcon: const Icon(LucideIcons.indianRupee),
                  onChanged: (val) {
                    setState(() => _isAmountPaidEdited = true);
                  },
                ),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: DropdownButtonFormField<String>(
                  value: _paymentMethod,
                  decoration: InputDecoration(
                    labelText: 'Method',
                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                  ),
                  items: const [
                    DropdownMenuItem(value: 'Cash', child: Text('Cash')),
                    DropdownMenuItem(value: 'UPI', child: Text('UPI / QR')),
                    DropdownMenuItem(value: 'Bank Transfer', child: Text('Bank Transfer')),
                    DropdownMenuItem(value: 'Card', child: Text('Card')),
                  ],
                  onChanged: (val) => setState(() => _paymentMethod = val!),
                ),
              ),
            ],
          ),
          const SizedBox(height: 14),
          if (activeWallets.isNotEmpty)
            DropdownButtonFormField<int>(
              value: _selectedWalletId ?? activeWallets.first.id,
              decoration: InputDecoration(
                labelText: 'Deposit To Account',
                prefixIcon: const Icon(LucideIcons.wallet),
                border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
              ),
              items: activeWallets.map((w) => DropdownMenuItem(
                value: w.id,
                child: Text('${w.name} (₹${w.balance.toStringAsFixed(0)})'),
              )).toList(),
              onChanged: (val) => setState(() => _selectedWalletId = val),
            ),
          
          if (balanceDue > 0) ...[
            const SizedBox(height: 14),
            Container(
              padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 10),
              decoration: BoxDecoration(
                color: (amountPaid > 0 ? Colors.orange : Colors.red).withValues(alpha: 0.08),
                borderRadius: BorderRadius.circular(12),
                border: Border.all(color: (amountPaid > 0 ? Colors.orange : Colors.red).withValues(alpha: 0.25)),
              ),
              child: Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Row(
                    children: [
                      Icon(
                        amountPaid > 0 ? LucideIcons.circleDot : LucideIcons.alertCircle,
                        size: 16,
                        color: amountPaid > 0 ? Colors.orange : Colors.red,
                      ),
                      const SizedBox(width: 8),
                      Text(
                        amountPaid > 0 ? 'Remaining Balance Due:' : 'Total Amount Due:',
                        style: TextStyle(
                          fontSize: 13,
                          fontWeight: FontWeight.w600,
                          color: isDark ? Colors.white70 : Colors.black87,
                        ),
                      ),
                    ],
                  ),
                  Text(
                    '₹${balanceDue.toStringAsFixed(2)}',
                    style: TextStyle(
                      fontSize: 15,
                      fontWeight: FontWeight.bold,
                      color: amountPaid > 0 ? Colors.orange.shade700 : Colors.red.shade700,
                    ),
                  ),
                ],
              ),
            ),
            const SizedBox(height: 14),
            InkWell(
              onTap: () async {
                final picked = await showDatePicker(
                  context: context,
                  initialDate: _nextPaymentDate ?? DateTime.now().add(const Duration(days: 30)),
                  firstDate: DateTime.now(),
                  lastDate: DateTime(2100),
                );
                if (picked != null) {
                  setState(() => _nextPaymentDate = picked);
                }
              },
              child: InputDecorator(
                decoration: InputDecoration(
                  labelText: 'Next Due / Balance Settlement Date',
                  prefixIcon: const Icon(LucideIcons.calendarClock),
                  border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                ),
                child: Text(
                  _nextPaymentDate != null ? DateFormat('dd MMM yyyy').format(_nextPaymentDate!) : 'Select Settlement Date (Default: 30 Days)',
                  style: const TextStyle(fontWeight: FontWeight.w600, fontSize: 13),
                ),
              ),
            ),
          ],

          const Divider(height: 28),

          // EMI Option Toggle
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              const Row(
                children: [
                  Icon(LucideIcons.creditCard, size: 18, color: Colors.purple),
                  SizedBox(width: 8),
                  Text('Enable EMI Installments', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 14)),
                ],
              ),
              Switch(
                value: _isEmi,
                activeColor: Colors.purple,
                onChanged: (val) => setState(() => _isEmi = val),
              ),
            ],
          ),

          if (_isEmi) ...[
            const SizedBox(height: 12),
            Row(
              children: [
                Expanded(
                  child: PremiumTextField(
                    controller: _emiAmountCtrl,
                    labelText: 'EMI Amount (₹)',
                    keyboardType: const TextInputType.numberWithOptions(decimal: true),
                    prefixIcon: const Icon(LucideIcons.indianRupee),
                  ),
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: DropdownButtonFormField<String>(
                    value: _emiCycle,
                    decoration: InputDecoration(
                      labelText: 'Cycle',
                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                    ),
                    items: const [
                      DropdownMenuItem(value: 'MONTHLY', child: Text('Monthly')),
                      DropdownMenuItem(value: 'WEEKLY', child: Text('Weekly')),
                    ],
                    onChanged: (val) => setState(() => _emiCycle = val!),
                  ),
                ),
              ],
            ),
          ],
        ],
      ),
    );
  }
}

class _AddSalesItemSheet extends ConsumerStatefulWidget {
  final ValueChanged<InvoiceItem> onItemAdded;
  final InvoiceItem? initialItem;

  const _AddSalesItemSheet({
    required this.onItemAdded,
    this.initialItem,
  });

  @override
  ConsumerState<_AddSalesItemSheet> createState() => _AddSalesItemSheetState();
}

class _AddSalesItemSheetState extends ConsumerState<_AddSalesItemSheet> {
  final _searchCtrl = TextEditingController();
  Product? _selectedProduct;
  InventoryItem? _selectedInventoryItem;

  final _makingChargeCtrl = TextEditingController(text: '0.0');
  String _makingChargeType = 'PER_GRAM';
  final _discountCtrl = TextEditingController(text: '0.0');

  @override
  void initState() {
    super.initState();
    Future.microtask(() => ref.invalidate(inventoryItemsProvider));
    if (widget.initialItem != null) {
      final it = widget.initialItem!;
      _makingChargeCtrl.text = it.makingCharge.toStringAsFixed(2);
      _makingChargeType = it.makingChargesType ?? 'PER_GRAM';
      _discountCtrl.text = it.discount.toStringAsFixed(2);

      WidgetsBinding.instance.addPostFrameCallback((_) {
        final products = ref.read(productsProvider).value ?? [];
        final invItems = ref.read(inventoryItemsProvider).value ?? [];
        setState(() {
          _selectedProduct = products.where((p) => p.id == it.productId).firstOrNull ??
              Product(
                id: it.productId,
                name: it.productName ?? 'Item',
                sku: it.sku,
                hsnCode: it.hsnCode,
                gstRate: it.taxRate,
                makingCharges: it.makingCharge,
                makingChargesType: it.makingChargesType,
              );
          if (it.inventoryItemId != null) {
            _selectedInventoryItem = invItems.where((i) => i.id == it.inventoryItemId).firstOrNull;
          }
        });
      });
    }
  }

  @override
  void dispose() {
    _searchCtrl.dispose();
    _makingChargeCtrl.dispose();
    _discountCtrl.dispose();
    super.dispose();
  }

  void _onProductSelected(Product product, ProductCategory? category, double liveCommodityRate) {
    setState(() {
      _selectedProduct = product;
      _selectedInventoryItem = null;
      
      if (product.makingCharges != null && product.makingCharges! > 0) {
        _makingChargeCtrl.text = product.makingCharges!.toStringAsFixed(2);
        _makingChargeType = product.makingChargesType ?? (category?.makingChargeType ?? 'PER_GRAM');
      } else if (category?.defaultMakingCharge != null && category!.defaultMakingCharge! > 0) {
        _makingChargeCtrl.text = category.defaultMakingCharge!.toStringAsFixed(2);
        _makingChargeType = category.makingChargeType ?? 'PER_GRAM';
      } else {
        _makingChargeCtrl.text = '0.0';
        _makingChargeType = category?.makingChargeType ?? 'PER_GRAM';
      }
    });
  }

  void _onInventoryItemSelected(InventoryItem item, Product product, ProductCategory? category) {
    setState(() {
      _selectedProduct = product;
      _selectedInventoryItem = item;

      if (item.makingCharges != null && item.makingCharges! > 0) {
        _makingChargeCtrl.text = item.makingCharges!.toStringAsFixed(2);
        _makingChargeType = item.makingChargeType ?? 'PER_GRAM';
      } else if (product.makingCharges != null && product.makingCharges! > 0) {
        _makingChargeCtrl.text = product.makingCharges!.toStringAsFixed(2);
        _makingChargeType = product.makingChargesType ?? (category?.makingChargeType ?? 'PER_GRAM');
      } else if (category?.defaultMakingCharge != null && category!.defaultMakingCharge! > 0) {
        _makingChargeCtrl.text = category.defaultMakingCharge!.toStringAsFixed(2);
        _makingChargeType = category.makingChargeType ?? 'PER_GRAM';
      } else {
        _makingChargeCtrl.text = '0.0';
        _makingChargeType = category?.makingChargeType ?? 'PER_GRAM';
      }
    });
  }

  Future<void> _scanBarcodeInSheet() async {
    final scanned = await Navigator.push<String>(
      context,
      MaterialPageRoute(builder: (_) => const BarcodeScannerScreen()),
    );
    if (scanned != null && scanned.isNotEmpty) {
      _searchCtrl.text = scanned;
      setState(() {});
    }
  }

  void _submitItem(ProductCategory? category, double unitRate) {
    if (_selectedProduct == null) return;

    final weight = _selectedInventoryItem?.grossWeight ?? 1.0;
    final makingCharge = double.tryParse(_makingChargeCtrl.text) ?? 0.0;
    final discount = double.tryParse(_discountCtrl.text) ?? 0.0;

    final metalAmount = weight * unitRate;
    double makingAmt = 0.0;
    if (_makingChargeType == 'PERCENTAGE') {
      makingAmt = metalAmount * (makingCharge / 100.0);
    } else if (_makingChargeType == 'PER_PIECE') {
      makingAmt = makingCharge;
    } else {
      makingAmt = weight * makingCharge;
    }

    final taxable = metalAmount + makingAmt - discount;
    final gstRate = _selectedProduct?.gstRate ?? (category?.defaultGst ?? 3.0);
    final taxAmount = (taxable * gstRate) / 100.0;
    final total = taxable + taxAmount;

    final item = InvoiceItem(
      productId: _selectedProduct!.id,
      inventoryItemId: _selectedInventoryItem?.id,
      productName: _selectedProduct!.name,
      categoryName: category?.name,
      commodityCode: category?.commodityCode,
      hsnCode: category?.defaultHsn ?? _selectedProduct?.hsnCode,
      sku: _selectedInventoryItem?.sku ?? _selectedProduct?.sku,
      huid: _selectedInventoryItem?.huid,
      description: _selectedProduct!.name,
      quantity: 1.0,
      weight: weight,
      unitPrice: unitRate,
      makingCharge: makingCharge,
      makingChargesType: _makingChargeType,
      taxRate: gstRate,
      discount: discount,
      photoUrl: _selectedInventoryItem?.tagNumber,
      total: total,
    );

    widget.onItemAdded(item);
    Navigator.pop(context);
  }

  @override
  Widget build(BuildContext context) {
    final products = ref.watch(productsProvider).value ?? [];
    final categories = ref.watch(productCategoriesProvider).value ?? [];
    final commodityRates = ref.watch(commodityRatesProvider).value ?? [];
    final inventoryItems = ref.watch(inventoryItemsProvider).value ?? [];

    final isDark = Theme.of(context).brightness == Brightness.dark;

    ProductCategory? category;
    if (_selectedProduct?.categoryId != null) {
      category = categories.where((c) => c.id == _selectedProduct!.categoryId).firstOrNull;
    }

    double commodityRate = 0.0;
    if (category?.commodityCode != null) {
      final match = commodityRates.where((r) => r.commodityCode.toUpperCase() == category!.commodityCode!.toUpperCase()).firstOrNull;
      if (match != null) {
        commodityRate = match.rate;
      }
    }
    final purityFactor = resolvePurity(categoryPurity: category?.purityFactor, productPurity: _selectedProduct?.purityFactor);
    final effectiveUnitRate = commodityRate > 0 ? (commodityRate * purityFactor) : (_selectedProduct?.sellingPrice ?? 0.0);

    final weight = _selectedInventoryItem?.grossWeight ?? 1.0;
    final metalAmount = weight * effectiveUnitRate;
    final makingCharge = double.tryParse(_makingChargeCtrl.text) ?? 0.0;
    
    double makingAmt = 0.0;
    if (_makingChargeType == 'PERCENTAGE') {
      makingAmt = metalAmount * (makingCharge / 100.0);
    } else if (_makingChargeType == 'PER_PIECE') {
      makingAmt = makingCharge;
    } else {
      makingAmt = weight * makingCharge;
    }

    final discount = double.tryParse(_discountCtrl.text) ?? 0.0;
    final taxable = metalAmount + makingAmt - discount;
    final gstRate = _selectedProduct?.gstRate ?? (category?.defaultGst ?? 3.0);
    final taxAmount = (taxable * gstRate) / 100.0;
    final total = taxable + taxAmount;

    final query = _searchCtrl.text.trim().toLowerCase();
    final availableItems = inventoryItems
        .where((item) => item.status == null || item.status == 'AVAILABLE')
        .toList();

    availableItems.sort((a, b) {
      if (a.createdAt == null && b.createdAt == null) return 0;
      if (a.createdAt == null) return 1;
      if (b.createdAt == null) return -1;
      return b.createdAt!.compareTo(a.createdAt!);
    });

    final List<InventoryItem> displayInventoryItems;
    if (query.isEmpty) {
      displayInventoryItems = availableItems.take(20).toList();
    } else {
      displayInventoryItems = availableItems.where((item) {
        final p = products.where((pr) => pr.id == item.productId).firstOrNull;
        final cat = p != null ? categories.where((c) => c.id == p.categoryId).firstOrNull : null;
        
        final matchesHuid = item.huid != null && item.huid!.toLowerCase().contains(query);
        final matchesSku = (item.sku != null && item.sku!.toLowerCase().contains(query)) ||
            (p?.sku != null && p!.sku!.toLowerCase().contains(query));
        final matchesName = p != null && p.name.toLowerCase().contains(query);
        final matchesBarcode = p != null && p.barcode != null && p.barcode!.toLowerCase().contains(query);
        final matchesCategory = cat != null && cat.name.toLowerCase().contains(query);
        final matchesTag = item.tagNumber != null && item.tagNumber!.toLowerCase().contains(query);

        return matchesHuid || matchesSku || matchesName || matchesBarcode || matchesCategory || matchesTag;
      }).take(20).toList();
    }

    final keyboardHeight = MediaQuery.of(context).viewInsets.bottom;

    return AnimatedPadding(
      padding: EdgeInsets.only(bottom: keyboardHeight),
      duration: const Duration(milliseconds: 150),
      curve: Curves.easeOut,
      child: GestureDetector(
        onTap: () => FocusScope.of(context).unfocus(),
        behavior: HitTestBehavior.translucent,
        child: Container(
          height: MediaQuery.of(context).size.height * 0.88,
          decoration: BoxDecoration(
            color: Theme.of(context).scaffoldBackgroundColor,
            borderRadius: const BorderRadius.vertical(top: Radius.circular(28)),
          ),
          child: Column(
            children: [
              Center(
                child: Container(
                  margin: const EdgeInsets.only(top: 12, bottom: 8),
                  width: 40,
                  height: 4,
                  decoration: BoxDecoration(
                    color: Colors.grey.withValues(alpha: 0.4),
                    borderRadius: BorderRadius.circular(2),
                  ),
                ),
              ),
              Padding(
                padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 8),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    const Text('Add Item to Invoice', style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
                    Row(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        if (keyboardHeight > 0)
                          TextButton.icon(
                            style: TextButton.styleFrom(
                              backgroundColor: Colors.blue.withValues(alpha: 0.12),
                              padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
                              shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
                            ),
                            icon: const Icon(LucideIcons.keyboard, size: 16, color: Colors.blue),
                            label: const Text('Done', style: TextStyle(fontWeight: FontWeight.bold, color: Colors.blue)),
                            onPressed: () => FocusScope.of(context).unfocus(),
                          ),
                        IconButton(
                          icon: const Icon(LucideIcons.x, size: 20),
                          onPressed: () => Navigator.pop(context),
                        ),
                      ],
                    ),
                  ],
                ),
              ),
              const Divider(height: 1),

              // Keyboard Toolbar when active on iOS/Android
              if (keyboardHeight > 0)
                Container(
                  color: isDark ? const Color(0xFF1E293B) : Colors.grey.shade100,
                  padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 6),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        'Editing ${_selectedProduct?.name ?? 'Item'}',
                        style: TextStyle(fontSize: 12, color: Colors.grey.shade600, fontWeight: FontWeight.w500),
                      ),
                      TextButton.icon(
                        style: TextButton.styleFrom(
                          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
                          backgroundColor: Colors.blue,
                          foregroundColor: Colors.white,
                          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
                        ),
                        icon: const Icon(LucideIcons.check, size: 15),
                        label: const Text('Done / Dismiss', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 13)),
                        onPressed: () => FocusScope.of(context).unfocus(),
                      ),
                    ],
                  ),
                ),

              Expanded(
                child: ListView(
                  keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
                  padding: const EdgeInsets.fromLTRB(20, 16, 20, 40),
                  children: [
                // Search Input with Barcode Action & Rounded Borders
                TextField(
                  controller: _searchCtrl,
                  decoration: InputDecoration(
                    labelText: 'Search Product by HUID / Name / SKU / Barcode',
                    prefixIcon: const Icon(LucideIcons.search),
                    suffixIcon: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        if (_searchCtrl.text.isNotEmpty)
                          IconButton(
                            icon: const Icon(LucideIcons.x),
                            onPressed: () => setState(() => _searchCtrl.clear()),
                          ),
                        IconButton(
                          icon: const Icon(LucideIcons.qrCode, color: Colors.blue),
                          tooltip: 'Scan Barcode',
                          onPressed: _scanBarcodeInSheet,
                        ),
                      ],
                    ),
                    border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                  ),
                  onChanged: (val) => setState(() {}),
                ),
                const SizedBox(height: 12),

                if (_selectedProduct == null) ...[
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        query.isEmpty
                            ? 'Available Stock in Inventory (${displayInventoryItems.length}):'
                            : 'Matched Inventory Items (${displayInventoryItems.length}):',
                        style: TextStyle(
                          fontSize: 12,
                          fontWeight: FontWeight.bold,
                          color: isDark ? Colors.grey.shade400 : Colors.grey.shade700,
                        ),
                      ),
                      if (query.isEmpty && availableItems.length > 20)
                        Text(
                          'Showing 20 newest',
                          style: TextStyle(fontSize: 11, color: Colors.grey.shade500, fontStyle: FontStyle.italic),
                        ),
                    ],
                  ),
                  const SizedBox(height: 10),
                  if (displayInventoryItems.isEmpty)
                    Padding(
                      padding: const EdgeInsets.symmetric(vertical: 40.0),
                      child: Center(
                        child: Column(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            Icon(LucideIcons.packageOpen, size: 40, color: Colors.grey.shade400),
                            const SizedBox(height: 10),
                            Text(
                              query.isEmpty
                                  ? 'No items available in stock'
                                  : 'No matching inventory items found',
                              style: TextStyle(color: Colors.grey.shade500, fontSize: 14),
                            ),
                          ],
                        ),
                      ),
                    )
                  else
                    ...displayInventoryItems.map((item) {
                      final p = products.where((pr) => pr.id == item.productId).firstOrNull ??
                          Product(
                            id: item.productId,
                            name: item.sku ?? 'Inventory Item',
                            sku: item.sku,
                          );
                      final cat = categories.where((c) => c.id == p.categoryId).firstOrNull;
                      double commRate = 0.0;
                      if (cat?.commodityCode != null) {
                        final m = commodityRates.where((r) => r.commodityCode.toUpperCase() == cat!.commodityCode!.toUpperCase()).firstOrNull;
                        if (m != null) commRate = m.rate;
                      }
                      return _buildSearchItemCard(
                        product: p,
                        category: cat,
                        inventoryItem: item,
                        commodityRate: commRate,
                        isDark: isDark,
                        onTap: () => _onInventoryItemSelected(item, p, cat),
                      );
                    }),
                ] else ...[
                  // SELECTED PRODUCT DETAILS CARD
                  Container(
                    padding: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: isDark ? const Color(0xFF1E293B) : Colors.blue.withValues(alpha: 0.05),
                      borderRadius: BorderRadius.circular(16),
                      border: Border.all(color: Colors.blue.withValues(alpha: 0.3)),
                    ),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: [
                            Expanded(
                              child: Text(
                                _selectedProduct!.name,
                                style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
                              ),
                            ),
                            TextButton(
                              onPressed: () => setState(() {
                                _selectedProduct = null;
                                _selectedInventoryItem = null;
                              }),
                              child: const Text('Change'),
                            ),
                          ],
                        ),
                        const SizedBox(height: 6),
                        Wrap(
                          spacing: 8,
                          runSpacing: 4,
                          children: [
                            if (category?.name != null)
                              _buildSheetBadge(category!.name, const Color(0xFFD4AF37)),
                            if (_selectedProduct!.sku != null)
                              _buildSheetBadge('SKU: ${_selectedProduct!.sku}', Colors.blue),
                            if (_selectedInventoryItem?.huid != null)
                              _buildSheetBadge('HUID: ${_selectedInventoryItem!.huid}', Colors.purple),
                            if (category?.commodityCode != null)
                              _buildSheetBadge('${category!.commodityCode} (${formatPurity(purityFactor)})', Colors.teal),
                            _buildSheetBadge('Purity: ${formatPurity(purityFactor)}', Colors.amber.shade800),
                          ],
                        ),
                      ],
                    ),
                  ),

                  const SizedBox(height: 16),

                  // DISABLED FIELDS: Rounded 12px borders
                  Row(
                    children: [
                      Expanded(
                        child: TextFormField(
                          initialValue: category?.defaultHsn ?? _selectedProduct?.hsnCode ?? '7113',
                          style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
                          enabled: false,
                          decoration: InputDecoration(
                            labelText: 'HSN Code',
                            prefixIcon: const Icon(LucideIcons.hash, size: 18),
                            contentPadding: const EdgeInsets.symmetric(horizontal: 10, vertical: 12),
                            border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                          ),
                        ),
                      ),
                      const SizedBox(width: 12),
                      Expanded(
                        child: TextFormField(
                          initialValue: '${weight.toStringAsFixed(3)} g',
                          style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
                          enabled: false,
                          decoration: InputDecoration(
                            labelText: 'Weight',
                            prefixIcon: const Icon(LucideIcons.scale, size: 18),
                            contentPadding: const EdgeInsets.symmetric(horizontal: 10, vertical: 12),
                            border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                          ),
                        ),
                      ),
                    ],
                  ),
                  const SizedBox(height: 12),

                  Row(
                    children: [
                      Expanded(
                        child: TextFormField(
                          key: ValueKey(effectiveUnitRate),
                          initialValue: '₹${effectiveUnitRate.toStringAsFixed(2)}/g',
                          style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
                          enabled: false,
                          decoration: InputDecoration(
                            labelText: 'Live Rate',
                            prefixIcon: const Icon(LucideIcons.trendingUp, size: 18),
                            contentPadding: const EdgeInsets.symmetric(horizontal: 10, vertical: 12),
                            border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                          ),
                        ),
                      ),
                      const SizedBox(width: 12),
                      Expanded(
                        child: TextFormField(
                          key: ValueKey(metalAmount),
                          initialValue: '₹${metalAmount.toStringAsFixed(2)}',
                          style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
                          enabled: false,
                          decoration: InputDecoration(
                            labelText: 'Metal Amount',
                            prefixIcon: const Icon(LucideIcons.coins, size: 18),
                            contentPadding: const EdgeInsets.symmetric(horizontal: 10, vertical: 12),
                            border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                          ),
                        ),
                      ),
                    ],
                  ),

                  const SizedBox(height: 16),

                  // ENABLED FIELDS: Making Charges & Type
                  Row(
                    children: [
                      Expanded(
                        child: PremiumTextField(
                          controller: _makingChargeCtrl,
                          labelText: 'Making Charges',
                          keyboardType: const TextInputType.numberWithOptions(decimal: true),
                          prefixIcon: const Icon(LucideIcons.hammer),
                          onChanged: (_) => setState(() {}),
                        ),
                      ),
                      const SizedBox(width: 12),
                      Expanded(
                        child: DropdownButtonFormField<String>(
                          value: _makingChargeType,
                          decoration: InputDecoration(
                            labelText: 'Type',
                            border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
                          ),
                          items: const [
                            DropdownMenuItem(value: 'PER_GRAM', child: Text('Per Gram')),
                            DropdownMenuItem(value: 'PER_PIECE', child: Text('Per Piece')),
                            DropdownMenuItem(value: 'PERCENTAGE', child: Text('Percentage %')),
                          ],
                          onChanged: (val) => setState(() => _makingChargeType = val!),
                        ),
                      ),
                    ],
                  ),
                  const SizedBox(height: 8),
                  Container(
                    padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
                    decoration: BoxDecoration(
                      color: Colors.indigo.withValues(alpha: 0.08),
                      borderRadius: BorderRadius.circular(10),
                      border: Border.all(color: Colors.indigo.withValues(alpha: 0.2)),
                    ),
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.spaceBetween,
                      children: [
                        const Text(
                          'Calculated Making Charge:',
                          style: TextStyle(fontSize: 13, fontWeight: FontWeight.w500),
                        ),
                        Text(
                          '₹${makingAmt.toStringAsFixed(2)}',
                          style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 14, color: Colors.indigo),
                        ),
                      ],
                    ),
                  ),

                  const SizedBox(height: 16),

                  // Calculated Subtotal & GST Display
                  Container(
                    padding: const EdgeInsets.all(16),
                    decoration: BoxDecoration(
                      color: isDark ? Colors.black26 : Colors.grey.shade100,
                      borderRadius: BorderRadius.circular(14),
                    ),
                    child: Column(
                      children: [
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: [
                            const Text('Taxable Subtotal:'),
                            Text('₹${taxable.toStringAsFixed(2)}', style: const TextStyle(fontWeight: FontWeight.bold)),
                          ],
                        ),
                        const SizedBox(height: 6),
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: [
                            Text('GST (${gstRate.toStringAsFixed(1)}%):'),
                            Text('+ ₹${taxAmount.toStringAsFixed(2)}', style: const TextStyle(fontWeight: FontWeight.bold, color: Colors.indigo)),
                          ],
                        ),
                        const Divider(height: 16),
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: [
                            const Text('Item Total:', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                            Text('₹${total.toStringAsFixed(2)}', style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold, color: Colors.green)),
                          ],
                        ),
                      ],
                    ),
                  ),

                  const SizedBox(height: 24),

                  ElevatedButton(
                    onPressed: () => _submitItem(category, effectiveUnitRate),
                    style: ElevatedButton.styleFrom(
                      padding: const EdgeInsets.symmetric(vertical: 16),
                      backgroundColor: Colors.blue,
                      foregroundColor: Colors.white,
                      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
                    ),
                    child: const Text('Add to Invoice', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                  ),
                ],
              ],
            ),
          ),
        ],
      ),
    ),
  ),
);
}

  Widget _buildSheetBadge(String text, Color color) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.12),
        borderRadius: BorderRadius.circular(6),
        border: Border.all(color: color.withValues(alpha: 0.4)),
      ),
      child: Text(
        text,
        style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold, color: color),
      ),
    );
  }

  Widget _buildSearchItemCard({
    required Product product,
    ProductCategory? category,
    InventoryItem? inventoryItem,
    required double commodityRate,
    required bool isDark,
    required VoidCallback onTap,
  }) {
    final purity = resolvePurity(categoryPurity: category?.purityFactor, productPurity: product.purityFactor);
    final unitRate = commodityRate > 0 ? (commodityRate * purity) : (product.sellingPrice ?? 0.0);
    final weight = inventoryItem?.grossWeight ?? 1.0;
    final metalAmount = weight * unitRate;

    final makingCharge = (inventoryItem?.makingCharges != null && inventoryItem!.makingCharges! > 0)
        ? inventoryItem.makingCharges!
        : ((product.makingCharges != null && product.makingCharges! > 0)
            ? product.makingCharges!
            : (category?.defaultMakingCharge ?? 0.0));
    final makingType = (inventoryItem?.makingChargeType != null && inventoryItem!.makingChargeType!.isNotEmpty)
        ? inventoryItem.makingChargeType!
        : ((product.makingCharges != null && product.makingCharges! > 0 && product.makingChargesType != null)
            ? product.makingChargesType!
            : (category?.makingChargeType ?? 'PER_GRAM'));
    
    double makingAmt = 0.0;
    if (makingType == 'PERCENTAGE') {
      makingAmt = metalAmount * (makingCharge / 100.0);
    } else if (makingType == 'PER_PIECE') {
      makingAmt = makingCharge;
    } else {
      makingAmt = weight * makingCharge;
    }

    final gstRate = product.gstRate ?? (category?.defaultGst ?? 3.0);
    final taxable = metalAmount + makingAmt;
    final taxAmount = (taxable * gstRate) / 100.0;
    final totalWithTax = taxable + taxAmount;

    final huid = inventoryItem?.huid;
    final sku = inventoryItem?.sku ?? product.sku;

    return Container(
      margin: const EdgeInsets.only(bottom: 12),
      decoration: BoxDecoration(
        color: isDark ? const Color(0xFF1E293B) : Colors.white,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: isDark ? Colors.white12 : Colors.grey.shade200),
        boxShadow: [
          BoxShadow(
            color: Colors.black.withValues(alpha: isDark ? 0.2 : 0.04),
            blurRadius: 8,
            offset: const Offset(0, 3),
          ),
        ],
      ),
      child: Material(
        color: Colors.transparent,
        borderRadius: BorderRadius.circular(16),
        child: InkWell(
          onTap: onTap,
          borderRadius: BorderRadius.circular(16),
          child: Padding(
            padding: const EdgeInsets.all(14),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Container(
                      padding: const EdgeInsets.all(8),
                      decoration: BoxDecoration(
                        color: (huid != null ? Colors.purple : Colors.blue).withValues(alpha: 0.12),
                        borderRadius: BorderRadius.circular(10),
                      ),
                      child: Icon(
                        huid != null ? LucideIcons.gem : LucideIcons.tag,
                        size: 20,
                        color: huid != null ? Colors.purple : Colors.blue,
                      ),
                    ),
                    const SizedBox(width: 10),
                    Expanded(
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(
                            product.name,
                            style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 15),
                          ),
                          const SizedBox(height: 4),
                          Wrap(
                            spacing: 6,
                            runSpacing: 4,
                            children: [
                              if (category?.name != null)
                                _buildSheetBadge(category!.name, const Color(0xFFD4AF37)),
                              if (sku != null && sku.isNotEmpty)
                                _buildSheetBadge('SKU: $sku', Colors.blue),
                              if (huid != null && huid.isNotEmpty)
                                _buildSheetBadge('HUID: $huid', Colors.purple),
                              _buildSheetBadge('Purity: ${formatPurity(purity)}', Colors.amber.shade900),
                            ],
                          ),
                        ],
                      ),
                    ),
                  ],
                ),
                const Divider(height: 18),
                Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Text(
                      'Rate: ₹${unitRate.toStringAsFixed(2)}/g • ${weight.toStringAsFixed(3)}g',
                      style: TextStyle(fontSize: 13, color: Colors.grey.shade600, fontWeight: FontWeight.w500),
                    ),
                    Text(
                      'Metal: ₹${metalAmount.toStringAsFixed(2)}',
                      style: const TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
                    ),
                  ],
                ),
                const SizedBox(height: 6),
                Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Container(
                      padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
                      decoration: BoxDecoration(
                        color: Colors.indigo.withValues(alpha: 0.1),
                        borderRadius: BorderRadius.circular(6),
                        border: Border.all(color: Colors.indigo.withValues(alpha: 0.2)),
                      ),
                      child: Text(
                        'Making: ${makingType == 'PERCENTAGE' ? '$makingCharge%' : (makingType == 'PER_PIECE' ? '₹$makingCharge/pc' : '₹$makingCharge/g')} (₹${makingAmt.toStringAsFixed(2)})',
                        style: const TextStyle(fontSize: 11, fontWeight: FontWeight.bold, color: Colors.indigo),
                      ),
                    ),
                    Column(
                      crossAxisAlignment: CrossAxisAlignment.end,
                      children: [
                        Text(
                          '₹${totalWithTax.toStringAsFixed(2)}',
                          style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16, color: Colors.green),
                        ),
                        Text(
                          'incl. ${gstRate.toStringAsFixed(1)}% GST',
                          style: TextStyle(fontSize: 10, color: Colors.grey.shade500),
                        ),
                      ],
                    ),
                  ],
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}