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

import '../app/app_router.dart';
import '../app/app_state.dart';
import '../services/api.dart';
import '../services/beacon_scanner_service.dart';

/// A button that triggers a beacon rescan
/// Can be used anywhere in the app - will use the current business if available
class RescanButton extends StatefulWidget {
  final bool showLabel;
  final Color? iconColor;

  const RescanButton({
    super.key,
    this.showLabel = false,
    this.iconColor,
  });

  @override
  State<RescanButton> createState() => _RescanButtonState();
}

class _RescanButtonState extends State<RescanButton> {
  final _scanner = BeaconScannerService();
  bool _isScanning = false;

  Future<void> _performRescan() async {
    if (_isScanning) return;

    setState(() => _isScanning = true);

    final appState = context.read<AppState>();
    final currentBusinessId = appState.selectedBusinessId;

    // Show scanning indicator
    final scaffold = ScaffoldMessenger.of(context);
    scaffold.showSnackBar(
      const SnackBar(
        content: Row(
          children: [
            SizedBox(
              width: 16,
              height: 16,
              child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white),
            ),
            SizedBox(width: 12),
            Text('Scanning for your table...'),
          ],
        ),
        duration: Duration(seconds: 3),
      ),
    );

    try {
      // Use current business for optimized scan if available
      final result = await _scanner.scan(businessId: currentBusinessId);

      if (!mounted) return;

      scaffold.hideCurrentSnackBar();

      if (result.foundBeacon) {
        final beacon = result.bestBeacon!;

        // Check if it's the same business/table or a new one
        // Also check if the beacon's business matches our parent (food court scenario)
        final isSameLocation = (beacon.businessId == currentBusinessId &&
            beacon.servicePointId == appState.selectedServicePointId);
        final isSameParentLocation = (appState.hasParentBusiness &&
            beacon.businessId == appState.parentBusinessId &&
            beacon.servicePointId == appState.selectedServicePointId);

        if (isSameLocation || isSameParentLocation) {
          // Same location - just confirm
          scaffold.showSnackBar(
            SnackBar(
              content: Text('Still at ${appState.selectedServicePointName ?? beacon.servicePointName}'),
              duration: const Duration(seconds: 2),
            ),
          );
        } else {
          // Different location - ask to switch
          _showSwitchDialog(beacon);
        }
      } else if (result.beaconsFound > 0) {
        scaffold.showSnackBar(
          SnackBar(
            content: Text('Found ${result.beaconsFound} beacon(s) but none registered'),
            duration: const Duration(seconds: 2),
          ),
        );
      } else {
        scaffold.showSnackBar(
          const SnackBar(
            content: Text('No beacons detected nearby'),
            duration: Duration(seconds: 2),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        scaffold.hideCurrentSnackBar();
        scaffold.showSnackBar(
          SnackBar(
            content: Text('Scan failed: $e'),
            duration: const Duration(seconds: 2),
          ),
        );
      }
    } finally {
      if (mounted) {
        setState(() => _isScanning = false);
      }
    }
  }

  void _showSwitchDialog(BeaconLookupResult beacon) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('New Location Detected'),
        content: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text('You appear to be at:'),
            const SizedBox(height: 8),
            Text(
              beacon.businessName,
              style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 16),
            ),
            if (beacon.servicePointName.isNotEmpty)
              Text(
                beacon.servicePointName,
                style: TextStyle(color: Colors.grey.shade600),
              ),
          ],
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('Stay Here'),
          ),
          FilledButton(
            onPressed: () {
              Navigator.pop(context);
              _switchToBeacon(beacon);
            },
            child: const Text('Switch'),
          ),
        ],
      ),
    );
  }

  Future<void> _switchToBeacon(BeaconLookupResult beacon) async {
    final appState = context.read<AppState>();

    // Handle parent business (food court scenario)
    if (beacon.hasChildren) {
      try {
        final children = await Api.getChildBusinesses(businessId: beacon.businessId);
        if (!mounted) return;

        if (children.isNotEmpty) {
          Navigator.of(context).pushReplacementNamed(
            AppRoutes.businessSelector,
            arguments: {
              'parentBusinessId': beacon.businessId,
              'parentBusinessName': beacon.businessName,
              'servicePointId': beacon.servicePointId,
              'servicePointName': beacon.servicePointName,
              'children': children,
            },
          );
          return;
        }
      } catch (e) {
        debugPrint('[Rescan] Error fetching children: $e');
      }
    }

    // Single business - update state and navigate
    appState.setBusinessAndServicePoint(
      beacon.businessId,
      beacon.servicePointId,
      businessName: beacon.businessName,
      servicePointName: beacon.servicePointName,
      parentBusinessId: beacon.hasParent ? beacon.parentBusinessId : null,
      parentBusinessName: beacon.hasParent ? beacon.parentBusinessName : null,
    );
    appState.setOrderType(OrderType.dineIn);
    Api.setBusinessId(beacon.businessId);

    if (!mounted) return;

    Navigator.of(context).pushReplacementNamed(
      AppRoutes.menuBrowse,
      arguments: {
        'businessId': beacon.businessId,
        'servicePointId': beacon.servicePointId,
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    if (widget.showLabel) {
      return TextButton.icon(
        onPressed: _isScanning ? null : _performRescan,
        icon: _isScanning
            ? const SizedBox(
                width: 16,
                height: 16,
                child: CircularProgressIndicator(strokeWidth: 2),
              )
            : Icon(Icons.bluetooth_searching, color: widget.iconColor),
        label: Text(
          _isScanning ? 'Scanning...' : 'Find My Table',
          style: TextStyle(color: widget.iconColor),
        ),
      );
    }

    return IconButton(
      icon: _isScanning
          ? const SizedBox(
              width: 20,
              height: 20,
              child: CircularProgressIndicator(strokeWidth: 2),
            )
          : Icon(Icons.bluetooth_searching, color: widget.iconColor),
      tooltip: 'Find My Table',
      onPressed: _isScanning ? null : _performRescan,
    );
  }
}