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

import '../../data/models/scan_item.dart';
import '../providers/form_provider.dart';
import '../providers/scanner_provider.dart';

/// Detail page for editing scan data with 4 text fields and Save/Print buttons
class DetailPage extends ConsumerStatefulWidget {
  final String barcode;

  const DetailPage({
    required this.barcode,
    super.key,
  });

  @override
  ConsumerState<DetailPage> createState() => _DetailPageState();
}

class _DetailPageState extends ConsumerState<DetailPage> {
  late final TextEditingController _field1Controller;
  late final TextEditingController _field2Controller;
  late final TextEditingController _field3Controller;
  late final TextEditingController _field4Controller;

  @override
  void initState() {
    super.initState();
    _field1Controller = TextEditingController();
    _field2Controller = TextEditingController();
    _field3Controller = TextEditingController();
    _field4Controller = TextEditingController();

    // Initialize controllers with existing data if available
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _loadExistingData();
    });
  }

  @override
  void dispose() {
    _field1Controller.dispose();
    _field2Controller.dispose();
    _field3Controller.dispose();
    _field4Controller.dispose();
    super.dispose();
  }

  /// Load existing data from history if available
  void _loadExistingData() {
    final history = ref.read(scanHistoryProvider);
    final existingScan = history.firstWhere(
      (item) => item.barcode == widget.barcode,
      orElse: () => ScanItem(barcode: widget.barcode, timestamp: DateTime.now()),
    );

    _field1Controller.text = existingScan.field1;
    _field2Controller.text = existingScan.field2;
    _field3Controller.text = existingScan.field3;
    _field4Controller.text = existingScan.field4;

    // Update form provider with existing data
    final formNotifier = ref.read(formProviderFamily(widget.barcode).notifier);
    formNotifier.populateWithScanItem(existingScan);
  }

  @override
  Widget build(BuildContext context) {
    final formState = ref.watch(formProviderFamily(widget.barcode));
    final formNotifier = ref.read(formProviderFamily(widget.barcode).notifier);

    // Listen to form state changes for navigation
    ref.listen<FormDetailState>(
      formProviderFamily(widget.barcode),
      (previous, next) {
        if (next.isSaveSuccess && (previous?.isSaveSuccess != true)) {
          _showSuccessAndNavigateBack(context);
        }
      },
    );

    return Scaffold(
      appBar: AppBar(
        title: const Text('Edit Details'),
        elevation: 0,
        leading: IconButton(
          icon: const Icon(Icons.arrow_back),
          onPressed: () => context.pop(),
        ),
      ),
      body: Column(
        children: [
          // Barcode Header
          Container(
            width: double.infinity,
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: Theme.of(context).colorScheme.surfaceVariant,
              border: Border(
                bottom: BorderSide(
                  color: Theme.of(context).dividerColor,
                  width: 1,
                ),
              ),
            ),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  'Barcode',
                  style: Theme.of(context).textTheme.labelMedium?.copyWith(
                        color: Theme.of(context).colorScheme.onSurfaceVariant,
                      ),
                ),
                const SizedBox(height: 4),
                Text(
                  widget.barcode,
                  style: Theme.of(context).textTheme.headlineSmall?.copyWith(
                        fontWeight: FontWeight.bold,
                        fontFamily: 'monospace',
                      ),
                ),
              ],
            ),
          ),

          // Form Fields
          Expanded(
            child: SingleChildScrollView(
              padding: const EdgeInsets.all(16),
              child: Column(
                children: [
                  // Field 1
                  _buildTextField(
                    controller: _field1Controller,
                    label: 'Field 1',
                    onChanged: formNotifier.updateField1,
                  ),
                  const SizedBox(height: 16),

                  // Field 2
                  _buildTextField(
                    controller: _field2Controller,
                    label: 'Field 2',
                    onChanged: formNotifier.updateField2,
                  ),
                  const SizedBox(height: 16),

                  // Field 3
                  _buildTextField(
                    controller: _field3Controller,
                    label: 'Field 3',
                    onChanged: formNotifier.updateField3,
                  ),
                  const SizedBox(height: 16),

                  // Field 4
                  _buildTextField(
                    controller: _field4Controller,
                    label: 'Field 4',
                    onChanged: formNotifier.updateField4,
                  ),
                  const SizedBox(height: 24),

                  // Error Message
                  if (formState.error != null) ...[
                    Container(
                      width: double.infinity,
                      padding: const EdgeInsets.all(12),
                      decoration: BoxDecoration(
                        color: Theme.of(context).colorScheme.errorContainer,
                        borderRadius: BorderRadius.circular(8),
                        border: Border.all(
                          color: Theme.of(context).colorScheme.error,
                          width: 1,
                        ),
                      ),
                      child: Row(
                        children: [
                          Icon(
                            Icons.error_outline,
                            color: Theme.of(context).colorScheme.error,
                            size: 20,
                          ),
                          const SizedBox(width: 8),
                          Expanded(
                            child: Text(
                              formState.error!,
                              style: Theme.of(context).textTheme.bodySmall?.copyWith(
                                    color: Theme.of(context).colorScheme.onErrorContainer,
                                  ),
                            ),
                          ),
                        ],
                      ),
                    ),
                    const SizedBox(height: 16),
                  ],
                ],
              ),
            ),
          ),

          // Action Buttons
          Container(
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: Theme.of(context).colorScheme.surface,
              border: Border(
                top: BorderSide(
                  color: Theme.of(context).dividerColor,
                  width: 1,
                ),
              ),
            ),
            child: SafeArea(
              child: Row(
                children: [
                  // Save Button
                  Expanded(
                    child: ElevatedButton(
                      onPressed: formState.isLoading ? null : () => _saveData(formNotifier),
                      style: ElevatedButton.styleFrom(
                        backgroundColor: Theme.of(context).colorScheme.primary,
                        foregroundColor: Theme.of(context).colorScheme.onPrimary,
                        minimumSize: const Size.fromHeight(48),
                      ),
                      child: formState.isLoading
                          ? const SizedBox(
                              width: 20,
                              height: 20,
                              child: CircularProgressIndicator(
                                strokeWidth: 2,
                                valueColor: AlwaysStoppedAnimation<Color>(Colors.white),
                              ),
                            )
                          : const Text('Save'),
                    ),
                  ),
                  const SizedBox(width: 16),

                  // Print Button
                  Expanded(
                    child: OutlinedButton(
                      onPressed: formState.isLoading ? null : () => _printData(formNotifier),
                      style: OutlinedButton.styleFrom(
                        minimumSize: const Size.fromHeight(48),
                      ),
                      child: const Text('Print'),
                    ),
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }

  /// Build text field widget
  Widget _buildTextField({
    required TextEditingController controller,
    required String label,
    required void Function(String) onChanged,
  }) {
    return TextField(
      controller: controller,
      decoration: InputDecoration(
        labelText: label,
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
        ),
        filled: true,
        fillColor: Theme.of(context).colorScheme.surfaceVariant.withOpacity(0.3),
      ),
      textCapitalization: TextCapitalization.sentences,
      onChanged: onChanged,
    );
  }

  /// Save form data
  Future<void> _saveData(FormNotifier formNotifier) async {
    // Clear any previous errors
    formNotifier.clearError();

    // Attempt to save
    await formNotifier.saveData();
  }

  /// Print form data
  Future<void> _printData(FormNotifier formNotifier) async {
    try {
      await formNotifier.printData();
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(
            content: Text('Print dialog opened'),
            backgroundColor: Colors.green,
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('Print failed: ${e.toString()}'),
            backgroundColor: Theme.of(context).colorScheme.error,
          ),
        );
      }
    }
  }

  /// Show success message and navigate back
  void _showSuccessAndNavigateBack(BuildContext context) {
    ScaffoldMessenger.of(context).showSnackBar(
      const SnackBar(
        content: Text('Data saved successfully!'),
        backgroundColor: Colors.green,
        duration: Duration(seconds: 2),
      ),
    );

    // Navigate back after a short delay
    Future.delayed(const Duration(milliseconds: 1500), () {
      if (mounted) {
        context.pop();
      }
    });
  }
}