import 'package:diameter/components/dialogs.dart';
import 'package:diameter/config.dart';
import 'package:diameter/utils/date_time_utils.dart';
import 'package:flutter/material.dart';
import 'package:diameter/components/progress_indicator.dart';
import 'package:diameter/models/basal.dart';
import 'package:diameter/models/basal_profile.dart';
import 'package:diameter/screens/basal/basal_detail.dart';

class BasalListScreen extends StatefulWidget {
  final BasalProfile? basalProfile;

  const BasalListScreen({Key? key, this.basalProfile}) : super(key: key);

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

class _BasalListScreenState extends State<BasalListScreen> {
  void refresh({String? message}) {
    setState(() {
      if (widget.basalProfile != null) {
        widget.basalProfile!.basalRates =
            Basal.fetchAllForBasalProfile(widget.basalProfile!);
      }
    });
    setState(() {
      if (message != null) {
        var snackBar = SnackBar(
          content: Text(message),
          duration: const Duration(seconds: 2),
        );
        ScaffoldMessenger.of(context)
          ..removeCurrentSnackBar()
          ..showSnackBar(snackBar);
      }
    });
  }

  void handleEditAction(Basal basal) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => BasalDetailScreen(
          basalProfile: widget.basalProfile!,
          basal: basal,
        ),
      ),
    ).then((message) => refresh(message: message));
  }

  void onDelete(Basal basal) {
    basal.delete().then((_) => refresh(message: 'Basal Rate deleted'));
  }

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

  String? validateTimePeriod(List<Basal> basalRates, int index) {
    Basal basal = basalRates[index];

    // check for gaps
    if (index == 0 &&
        (basal.startTime.hour != 0 || basal.startTime.minute != 0)) {
      return 'First Basal of the day needs to start at 00:00';
    }

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

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

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

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

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

  @override
  Widget build(BuildContext context) {
    return SingleChildScrollView(
      child: Column(
        children: [
          FutureBuilder<List<Basal>>(
            future: widget.basalProfile!.basalRates,
            builder: (context, snapshot) {
              return ViewWithProgressIndicator(
                snapshot: snapshot,
                child: snapshot.data == null || snapshot.data!.isEmpty
                    ? const Padding(
                        padding: EdgeInsets.all(10.0),
                        child: Text('No Basal Rates for this Profile'),
                      )
                    : ListView.builder(
                        shrinkWrap: true,
                        itemCount:
                            snapshot.data != null ? snapshot.data!.length : 0,
                        itemBuilder: (context, index) {
                          final basal = snapshot.data![index];
                          final error =
                              validateTimePeriod(snapshot.data!, index);
                          return ListTile(
                            tileColor:
                                error != null ? Colors.red.shade100 : null,
                            onTap: () {
                              handleEditAction(basal);
                            },
                            title: Row(
                              mainAxisSize: MainAxisSize.max,
                              children: [
                                Expanded(
                                    child: Text(
                                        '${DateTimeUtils.displayTime(basal.startTime)} - ${DateTimeUtils.displayTime(basal.endTime)}')),
                                const Spacer(),
                                Expanded(child: Text('${basal.units} U')),
                              ],
                            ),
                            subtitle: error != null
                                ? Text(error,
                                    style: const TextStyle(color: Colors.red))
                                : Container(),
                            trailing: Row(
                              mainAxisSize: MainAxisSize.min,
                              children: [
                                IconButton(
                                  icon: const Icon(
                                    Icons.delete,
                                    color: Colors.blue,
                                  ),
                                  onPressed: () => handleDeleteAction(basal),
                                ),
                              ],
                            ),
                          );
                        },
                      ),
              );
            },
          ),
        ],
      ),
    );
  }
}