import 'package:abawo_bt_app/controller/bluetooth.dart';
import 'package:abawo_bt_app/model/shifter_types.dart';
import 'package:flutter/material.dart';
import 'package:flutter_reactive_ble/flutter_reactive_ble.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

class BikeScanDialog extends ConsumerStatefulWidget {
  const BikeScanDialog({
    required this.excludedDeviceId,
    super.key,
  });

  final String excludedDeviceId;

  static Future<DiscoveredDevice?> show(
    BuildContext context, {
    required String excludedDeviceId,
  }) {
    return showDialog<DiscoveredDevice>(
      context: context,
      barrierDismissible: true,
      builder: (_) => BikeScanDialog(excludedDeviceId: excludedDeviceId),
    );
  }

  @override
  ConsumerState<BikeScanDialog> createState() => _BikeScanDialogState();
}

class _BikeScanDialogState extends ConsumerState<BikeScanDialog> {
  bool _showAll = false;
  BluetoothController? _controller;

  @override
  void initState() {
    super.initState();
    _startScan();
  }

  Future<void> _startScan() async {
    final controller = await ref.read(bluetoothProvider.future);
    _controller = controller;
    await controller.stopScan();
    await controller.startScan();
  }

  @override
  void dispose() {
    _controller?.stopScan();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final btAsync = ref.watch(bluetoothProvider);
    final size = MediaQuery.of(context).size;
    final dialogWidth = size.width < 640 ? size.width - 24 : 560.0;
    final dialogHeight = size.height < 780 ? size.height * 0.78 : 560.0;

    return Dialog(
      clipBehavior: Clip.antiAlias,
      insetPadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 24),
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(28)),
      child: SizedBox(
        width: dialogWidth,
        height: dialogHeight,
        child: btAsync.when(
          loading: () => const Center(child: CircularProgressIndicator()),
          error: (err, _) => Center(child: Text('Bluetooth error: $err')),
          data: (controller) {
            _controller ??= controller;
            return Column(
              children: [
                _DialogHeader(
                  showAll: _showAll,
                  onChanged: (value) {
                    setState(() {
                      _showAll = value;
                    });
                  },
                  onRescan: _startScan,
                ),
                Expanded(
                  child: StreamBuilder<List<DiscoveredDevice>>(
                    stream: controller.scanResultsStream,
                    initialData: controller.scanResults,
                    builder: (context, snapshot) {
                      final devices = _filteredDevices(snapshot.data ?? const []);
                      if (devices.isEmpty) {
                        return const Padding(
                          padding: EdgeInsets.all(20),
                          child: Center(
                            child: Text(
                              'No matching trainers nearby. Keep scanning or enable Show All to inspect every device in range.',
                              textAlign: TextAlign.center,
                            ),
                          ),
                        );
                      }

                      return ListView.separated(
                        padding: const EdgeInsets.fromLTRB(20, 0, 20, 20),
                        itemCount: devices.length,
                        separatorBuilder: (_, __) => const SizedBox(height: 12),
                        itemBuilder: (context, index) {
                          final device = devices[index];
                          final isFtms =
                              device.serviceUuids.contains(Uuid.parse(ftmsServiceUuid));
                          return Material(
                            color: Theme.of(context).colorScheme.surface,
                            borderRadius: BorderRadius.circular(22),
                            child: InkWell(
                              borderRadius: BorderRadius.circular(22),
                              onTap: () => Navigator.of(context).pop(device),
                              child: Container(
                                padding: const EdgeInsets.all(16),
                                decoration: BoxDecoration(
                                  borderRadius: BorderRadius.circular(22),
                                  border: Border.all(
                                    color: Theme.of(context)
                                        .colorScheme
                                        .outlineVariant
                                        .withValues(alpha: 0.55),
                                  ),
                                ),
                                child: Row(
                                  children: [
                                    Container(
                                      width: 50,
                                      height: 50,
                                      decoration: BoxDecoration(
                                        shape: BoxShape.circle,
                                        color: Theme.of(context)
                                            .colorScheme
                                            .primary
                                            .withValues(alpha: 0.12),
                                      ),
                                      child: Icon(
                                        Icons.pedal_bike_rounded,
                                        color: Theme.of(context)
                                            .colorScheme
                                            .primary,
                                      ),
                                    ),
                                    const SizedBox(width: 14),
                                    Expanded(
                                      child: Column(
                                        crossAxisAlignment:
                                            CrossAxisAlignment.start,
                                        children: [
                                          Text(
                                            device.name.isEmpty
                                                ? 'Unknown Device'
                                                : device.name,
                                            maxLines: 1,
                                            overflow: TextOverflow.ellipsis,
                                            style: Theme.of(context)
                                                .textTheme
                                                .titleMedium
                                                ?.copyWith(
                                                  fontWeight: FontWeight.w700,
                                                ),
                                          ),
                                          const SizedBox(height: 4),
                                          Text(
                                            isFtms ? 'FTMS' : 'Nearby trainer',
                                            style: Theme.of(context)
                                                .textTheme
                                                .bodyMedium
                                                ?.copyWith(
                                                  color: Theme.of(context)
                                                      .colorScheme
                                                      .primary,
                                                  fontWeight: FontWeight.w600,
                                                ),
                                          ),
                                          const SizedBox(height: 4),
                                          Text(
                                            device.id,
                                            maxLines: 1,
                                            overflow: TextOverflow.ellipsis,
                                            style: Theme.of(context)
                                                .textTheme
                                                .bodySmall
                                                ?.copyWith(
                                                  color: Theme.of(context)
                                                      .colorScheme
                                                      .onSurface
                                                      .withValues(alpha: 0.62),
                                                ),
                                          ),
                                        ],
                                      ),
                                    ),
                                    const SizedBox(width: 12),
                                    Column(
                                      crossAxisAlignment: CrossAxisAlignment.end,
                                      children: [
                                        _RssiBadge(rssi: device.rssi),
                                        const SizedBox(height: 12),
                                        Icon(
                                          Icons.chevron_right_rounded,
                                          color: Theme.of(context)
                                              .colorScheme
                                              .onSurface
                                              .withValues(alpha: 0.55),
                                        ),
                                      ],
                                    ),
                                  ],
                                ),
                              ),
                            ),
                          );
                        },
                      );
                    },
                  ),
                ),
              ],
            );
          },
        ),
      ),
    );
  }

  List<DiscoveredDevice> _filteredDevices(List<DiscoveredDevice> devices) {
    final ftmsUuid = Uuid.parse(ftmsServiceUuid);
    return devices.where((device) {
      if (device.id == widget.excludedDeviceId) {
        return false;
      }
      if (_showAll) {
        return true;
      }
      return device.serviceUuids.contains(ftmsUuid);
    }).toList(growable: false);
  }
}

class _DialogHeader extends StatelessWidget {
  const _DialogHeader({
    required this.showAll,
    required this.onChanged,
    required this.onRescan,
  });

  final bool showAll;
  final ValueChanged<bool> onChanged;
  final VoidCallback onRescan;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(20, 20, 20, 16),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      'Assign Trainer',
                      style: Theme.of(context).textTheme.headlineSmall?.copyWith(
                            fontWeight: FontWeight.w700,
                          ),
                    ),
                    const SizedBox(height: 6),
                    Text(
                      'Tap a nearby trainer to assign it to the connected shifter.',
                      style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                            color: Theme.of(context)
                                .colorScheme
                                .onSurface
                                .withValues(alpha: 0.68),
                          ),
                    ),
                  ],
                ),
              ),
              IconButton(
                tooltip: 'Close',
                onPressed: () => Navigator.of(context).pop(),
                icon: const Icon(Icons.close),
              ),
            ],
          ),
          const SizedBox(height: 16),
          Row(
            children: [
              Expanded(
                child: Row(
                  children: [
                    Text(
                      'Show All',
                      style: Theme.of(context).textTheme.bodyMedium?.copyWith(
                            fontWeight: FontWeight.w600,
                          ),
                    ),
                    const SizedBox(width: 8),
                    Switch(value: showAll, onChanged: onChanged),
                  ],
                ),
              ),
              OutlinedButton.icon(
                onPressed: onRescan,
                icon: const Icon(Icons.refresh),
                label: const Text('Rescan'),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

class _RssiBadge extends StatelessWidget {
  const _RssiBadge({required this.rssi});

  final int rssi;

  @override
  Widget build(BuildContext context) {
    final color = rssi > -65
        ? const Color(0xFF40C979)
        : rssi > -80
            ? const Color(0xFFFFB649)
            : Theme.of(context).colorScheme.error;

    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.15),
        borderRadius: BorderRadius.circular(999),
      ),
      child: Text(
        '$rssi dBm',
        style: TextStyle(
          color: color,
          fontWeight: FontWeight.w700,
          fontSize: 12,
        ),
      ),
    );
  }
}