import 'package:diameter/components/dialogs.dart';
import 'package:diameter/models/settings.dart';
import 'package:diameter/utils/date_time_utils.dart';
import 'package:flutter/material.dart';
import 'package:diameter/models/bolus.dart';
import 'package:diameter/models/bolus_profile.dart';
import 'package:diameter/screens/bolus/bolus_detail.dart';

class BolusListScreen extends StatefulWidget {
  final BolusProfile bolusProfile;
  final List<Bolus> bolusRates;
  final Function() reload;

  const BolusListScreen(
      {Key? key, required this.bolusProfile, this.bolusRates = const [], required this.reload})
      : super(key: key);

  @override
  _BolusListScreenState createState() => _BolusListScreenState();
}

class _BolusListScreenState extends State<BolusListScreen> {
  final ScrollController _scrollController = ScrollController();

  void reload({String? message}) {
    widget.reload();

    setState(() {
      if (message != null) {
        var snackBar = SnackBar(
          content: Text(message),
          duration: const Duration(seconds: 2),
        );
        ScaffoldMessenger.of(context)
          ..removeCurrentSnackBar()
          ..showSnackBar(snackBar);
      }
    });
  }

  void handleEditAction(Bolus bolus) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => BolusDetailScreen(
          bolusProfileId: widget.bolusProfile.id,
          id: bolus.id,
        ),
      ),
    ).then((result) => reload(message: result?[0]));
  }

  void onDelete(Bolus bolus) {
    Bolus.remove(bolus.id);
    reload(message: 'Bolus Rate deleted');
  }

  void handleDeleteAction(Bolus bolus) async {
    if (Settings.get().showConfirmationDialogOnDelete) {
      Dialogs.showConfirmationDialog(
        context: context,
        onConfirm: () => onDelete(bolus),
        message: 'Are you sure you want to delete this Bolus Rate?',
      );
    } else {
      onDelete(bolus);
    }
  }

  String? validateTimePeriod(int index) {
    List<Bolus> bolusRates = widget.bolusRates;
    Bolus bolus = bolusRates[index];

    if (index == 0 &&
        (bolus.startTime.toLocal().hour != 0 || bolus.startTime.minute != 0)) {
      return 'First Bolus of the day needs to start at 00:00';
    }

    if (index > 0) {
      var lastEndTime = bolusRates[index - 1].endTime;
      if (bolus.startTime.isAfter(lastEndTime)) {
        return 'There\'s a time gap between this and the previous rate';
      }
    }

    if (index == bolusRates.length - 1 &&
        (bolus.endTime.toLocal().hour != 0 || bolus.endTime.minute != 0)) {
      return 'Last Bolus of the day needs to end at 00:00';
    }

    // check for duplicates
    if (bolusRates
        .where((other) => bolus != other && bolus.startTime == other.startTime)
        .isNotEmpty) {
      return 'There are multiple rates with this start time';
    }

    if (bolusRates
        .where((other) =>
            bolus.startTime.isBefore(other.startTime) &&
            bolus.endTime.isAfter(other.startTime))
        .isNotEmpty) {
      return 'This rate\'s time period overlaps with another one';
    }
  }

  @override
  Widget build(BuildContext context) {
    return widget.bolusRates.isNotEmpty ? Scrollbar(
      controller: _scrollController,
      child: ListView.builder(
        padding: const EdgeInsets.all(10.0),
        controller: _scrollController,
        shrinkWrap: true,
        itemCount: widget.bolusRates.length,
        itemBuilder: (context, index) {
          final bolus = widget.bolusRates[index];
          final error = validateTimePeriod(index);
          return Card(
            child: Column(
              children: [
                error != null
                  ? Padding(
                    padding: const EdgeInsets.all(5.0),
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Icon(Icons.warning, color: Theme.of(context).errorColor),
                        Text(
                          error, style: TextStyle(color: Theme.of(context).errorColor)
                        ),
                      ],
                    ),
                  ) : Container(),
                ListTile(
                  onTap: () {
                    handleEditAction(bolus);
                  },
                  isThreeLine: true,
                  title: Text('${DateTimeUtils.displayTime(bolus.startTime)} - ${DateTimeUtils.displayTime(bolus.endTime)}'),
                  subtitle: Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Expanded(
                        child: Column(
                          children: (bolus.units > 0 && bolus.carbs > 0)
                              ? [
                                  Text((bolus.carbs / bolus.units).toStringAsPrecision(2)),
                                  Text('${Settings.nutritionMeasurementSuffix} carbs per U',
                                      textAlign: TextAlign.center, textScaleFactor: 0.75),
                                ]
                              : [],
                        ),
                      ),
                      Expanded(
                        child: Column(
                          children: (bolus.units > 0 && bolus.carbs > 0)
                              ? [
                                  Text((bolus.units / bolus.carbs * 12).toStringAsPrecision(2)),
                                  const Text('U per bread unit',
                                      textAlign: TextAlign.center, textScaleFactor: 0.75),
                                ]
                              : [],
                        ),
                      ),
                      Expanded(
                        child: Column(
                          children: (bolus.units > 0 && (bolus.mgPerDl ?? bolus.mmolPerL ?? 0) > 0)
                              ? [
                                  Text((((Settings.glucoseMeasurement == GlucoseMeasurement.mgPerDl ? bolus.mgPerDl : bolus.mmolPerL ?? 0)! / bolus.units)).toString()),
                                  Text('${Settings.glucoseMeasurementSuffix} per unit',
                                      textAlign: TextAlign.center, textScaleFactor: 0.75),
                                ]
                              : [],
                        ),
                      ),
                    ],
                  ),
                  trailing: Row(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      IconButton(
                        icon: const Icon(
                          Icons.delete,
                          color: Colors.blue,
                        ),
                        onPressed: () => handleDeleteAction(bolus),
                      ),
                    ],
                  ),
                ),
              ],
            ),
          );
        },
      ),
    ) : const Center(
              child: Text('You have not created any Bolus Rates yet!'),
            );
  }
}