import 'dart:math';

import 'package:diameter/components/detail.dart';
import 'package:diameter/components/dialogs.dart';
import 'package:diameter/components/dropdown.dart';
import 'package:diameter/components/forms.dart';
import 'package:diameter/config.dart';
import 'package:diameter/models/bolus.dart';
import 'package:diameter/models/log_bolus.dart';
import 'package:diameter/models/log_entry.dart';
import 'package:diameter/models/log_meal.dart';
import 'package:diameter/navigation.dart';
import 'package:diameter/settings.dart';
import 'package:diameter/utils/utils.dart';
import 'package:flutter/material.dart';

enum BolusType {
  meal,
  glucose,
}

enum GlucoseParameter {
  mgdlCurrent,
  mgdlTarget,
  mgdlCorrection,
  mmolCurrent,
  mmolTarget,
  mmolCorrection,
}

class LogBolusDetailScreen extends StatefulWidget {
  static const String routeName = '/log-bolus';

  final int logEntryId;
  final int id;

  const LogBolusDetailScreen(
      {Key? key, this.logEntryId = 0, this.id = 0})
      : super(key: key);

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

class _LogBolusDetailScreenState extends State<LogBolusDetailScreen> {
  LogEntry? _logEntry;
  LogBolus? _logBolus;

  bool _isNew = true;
  bool _isSaving = false;

  final GlobalKey<FormState> _logBolusForm = GlobalKey<FormState>();

  final _unitsController = TextEditingController(text: '');
  final _carbsController = TextEditingController(text: '');
  final _mgPerDlCurrentController = TextEditingController(text: '');
  final _mgPerDlTargetController = TextEditingController(text: '');
  final _mgPerDlCorrectionController = TextEditingController(text: '');
  final _mmolPerLCurrentController = TextEditingController(text: '');
  final _mmolPerLTargetController = TextEditingController(text: '');
  final _mmolPerLCorrectionController = TextEditingController(text: '');
  final _delayController = TextEditingController(text: '');
  final _notesController = TextEditingController(text: '');

  bool _setManually = false;
  BolusType _bolusType = BolusType.meal;
  LogMeal? _meal;
  Bolus? _rate;

  List<LogMeal> _logMeals = [];

  @override
  void initState() {
    super.initState();
    reload();

    _logEntry = LogEntry.get(widget.logEntryId);
    _logMeals = LogMeal.getAllForEntry(widget.logEntryId);

    if (widget.id != 0) {
      _carbsController.text = (_logBolus!.carbs ?? '').toString();
      _delayController.text = (_logBolus!.delay ?? '').toString();
      _notesController.text = _logBolus!.notes ?? '';
      _setManually = _logBolus!.setManually;
      _meal = _logBolus!.meal.target;
      _rate = _logBolus!.rate.target;
    }

    _rate ??= Bolus.getRateForTime(_logEntry?.time);
    
    _mgPerDlCurrentController.text =
        (_logBolus?.mgPerDlCurrent ?? (LogEntry.hasUncorrectedGlucose(widget.logEntryId) ? _logEntry?.mgPerDl ?? 0 : 0)).toString();
    _mgPerDlTargetController.text =
        (_logBolus?.mgPerDlTarget ?? moderateGlucoseMgPerDl).toString();
    _mgPerDlCorrectionController.text =
        (_logBolus?.mgPerDlCorrection ?? max((int.tryParse(_mgPerDlCurrentController.text) ?? 0) - (int.tryParse(_mgPerDlTargetController.text) ?? 0), 0)).toString();
    _mmolPerLCurrentController.text =
        (_logBolus?.mmolPerLCurrent ?? (LogEntry.hasUncorrectedGlucose(widget.logEntryId) ? _logEntry?.mmolPerL ?? 0 : 0)).toString();
    _mmolPerLTargetController.text =
        (_logBolus?.mmolPerLTarget ?? moderateGlucoseMmolPerL).toString();
    _mmolPerLCorrectionController.text =
        (_logBolus?.mmolPerLCorrection ?? max((double.tryParse(_mmolPerLCurrentController.text) ?? 0) - (double.tryParse(_mmolPerLTargetController.text) ?? 0), 0)).toString();

    _unitsController.text = (_logBolus?.units ??
      (_rate != null && !_setManually ? ((int.tryParse(_mgPerDlCorrectionController.text) ?? 0) / ((_rate!.mgPerDl ?? 0) / _rate!.units)) : 0)
    ).toString();

    if (widget.id == 0 && LogEntry.hasUncorrectedGlucose(widget.logEntryId)) {
      _bolusType = BolusType.glucose;
    }
  }

  void reload() {
    if (widget.id != 0) {
      setState(() {
        _logBolus = LogBolus.get(widget.id);
      });
    }
    _isNew = _logBolus == null;
  }

  void onSelectMeal(LogMeal meal) {
    setState(() {
      _meal = meal;
      if (meal.carbsPerPortion != null) {
        _carbsController.text = meal.carbsPerPortion.toString();
        onChangeCarbs();
      }
    });
  }

  void onChangeCarbs() {
    setState(() {
      if (_rate != null && !_setManually) {
        _unitsController.text = ((double.tryParse(_carbsController.text) ?? 0) /
                (_rate!.carbs / _rate!.units))
            .toString();
      }
    });
  }

  void onChangeGlucose({GlucoseMeasurement? calculateFrom}) {
    int? mgPerDlCurrent;
    int? mgPerDlTarget;
    int? mgPerDlCorrection;

    double? mmolPerLCurrent;
    double? mmolPerLTarget;
    double? mmolPerLCorrection;

    if (calculateFrom != GlucoseMeasurement.mmolPerL &&
        _mgPerDlCurrentController.text != '' &&
        _mgPerDlTargetController.text != '') {
      mgPerDlCurrent = int.tryParse(_mgPerDlCurrentController.text);
      mgPerDlTarget = int.tryParse(_mgPerDlTargetController.text);
      mgPerDlCorrection = max((mgPerDlCurrent ?? 0) - (mgPerDlTarget ?? 0), 0);
    }
    if (calculateFrom != GlucoseMeasurement.mgPerDl &&
        _mmolPerLCurrentController.text != '') {
      mmolPerLCurrent = double.tryParse(_mmolPerLCurrentController.text);
      mmolPerLTarget = double.tryParse(_mmolPerLTargetController.text);
      mmolPerLCorrection =
          max((mmolPerLCurrent ?? 0) - (mmolPerLTarget ?? 0), 0);
    }

    if ((mgPerDlCurrent != null && mmolPerLCurrent == null) ||
        (mgPerDlTarget != null && mmolPerLTarget == null) ||
        (mgPerDlCorrection != null && mmolPerLCorrection == null)) {
      setState(() {
        _mgPerDlCorrectionController.text = (mgPerDlCorrection ?? 0).toString();
        _mmolPerLCurrentController.text =
            Utils.convertMgPerDlToMmolPerL(mgPerDlCurrent ?? 0).toString();
        _mmolPerLTargetController.text =
            Utils.convertMgPerDlToMmolPerL(mgPerDlTarget ?? 0).toString();
        _mmolPerLCorrectionController.text =
            Utils.convertMgPerDlToMmolPerL(mgPerDlCorrection ?? 0).toString();
        if (_rate != null && !_setManually) {
          _unitsController.text = ((mgPerDlCorrection ?? 0) /
                  ((_rate!.mgPerDl ?? 0) / _rate!.units))
              .toString();
        }
      });
    }
    if ((mmolPerLCurrent != null && mgPerDlCurrent == null) ||
        (mmolPerLTarget != null && mgPerDlTarget == null) ||
        (mmolPerLCorrection != null && mgPerDlCorrection == null)) {
      setState(() {
        _mmolPerLCurrentController.text = (mmolPerLCorrection ?? 0).toString();
        _mgPerDlCurrentController.text =
            Utils.convertMmolPerLToMgPerDl(mmolPerLCurrent ?? 0).toString();
        _mgPerDlTargetController.text =
            Utils.convertMmolPerLToMgPerDl(mmolPerLTarget ?? 0).toString();
        _mgPerDlCorrectionController.text =
            Utils.convertMmolPerLToMgPerDl(mmolPerLCorrection ?? 0).toString();
        if (_rate != null && !_setManually) {
          _unitsController.text = ((mmolPerLCorrection ?? 0) /
                  ((_rate!.mmolPerL ?? 0) / _rate!.units))
              .toString();
        }
      });
    }
  }

  void handleSaveAction() async {
    setState(() {
      _isSaving = true;
    });
    if (_logBolusForm.currentState!.validate()) {
      LogBolus logBolus = LogBolus(
        id: widget.id,
        units: double.tryParse(_unitsController.text) ?? 0,
        delay: int.tryParse(_delayController.text),
        setManually: _setManually,
        notes: _notesController.text,
      );
      if (_bolusType == BolusType.meal) {
        logBolus.carbs = double.tryParse(_carbsController.text);
        logBolus.mgPerDlCurrent = null;
        logBolus.mmolPerLCurrent = null;
      } else {
        logBolus.carbs = null;
        logBolus.mgPerDlCurrent = int.tryParse(_mgPerDlCurrentController.text);
        logBolus.mmolPerLCurrent =
            double.tryParse(_mmolPerLCurrentController.text);
        logBolus.mgPerDlTarget = int.tryParse(_mgPerDlTargetController.text);
        logBolus.mmolPerLTarget =
            double.tryParse(_mmolPerLTargetController.text);
        logBolus.mgPerDlCorrection = int.tryParse(_mgPerDlCorrectionController.text);
        logBolus.mmolPerLCorrection =
            double.tryParse(_mmolPerLCorrectionController.text);
      }
      logBolus.logEntry.target = _logEntry;
      logBolus.meal.target = _meal;
      logBolus.rate.target = _rate;
      LogBolus.put(logBolus);
      Navigator.pop(context, '${_isNew ? 'New' : ''} Bolus Saved');
    }
    setState(() {
      _isSaving = false;
    });
  }

  void handleCancelAction() {
    if (showConfirmationDialogOnCancel &&
        ((_isNew &&
                (_unitsController.text != '' ||
                    _carbsController.text != '' ||
                    _mgPerDlCurrentController.text != '' ||
                    _mgPerDlTargetController.text != '' ||
                    _mgPerDlCorrectionController.text != '' ||
                    _mmolPerLCurrentController.text != '' ||
                    _mmolPerLTargetController.text != '' ||
                    _mmolPerLCorrectionController.text != '' ||
                    _delayController.text != '' ||
                    _setManually ||
                    _notesController.text != '')) ||
            (!_isNew &&
                (double.tryParse(_unitsController.text) != _logBolus!.units ||
                    double.tryParse(_carbsController.text) !=
                        _logBolus!.carbs ||
                    int.tryParse(_mgPerDlCurrentController.text) !=
                        _logBolus!.mgPerDlCurrent ||
                    int.tryParse(_mgPerDlTargetController.text) !=
                        _logBolus!.mgPerDlTarget ||
                    int.tryParse(_mgPerDlCorrectionController.text) !=
                        _logBolus!.mgPerDlCorrection ||
                    double.tryParse(_mmolPerLCurrentController.text) !=
                        _logBolus!.mmolPerLCurrent ||
                    double.tryParse(_mmolPerLTargetController.text) !=
                        _logBolus!.mmolPerLTarget ||
                    double.tryParse(_mmolPerLCorrectionController.text) !=
                        _logBolus!.mmolPerLCorrection ||
                    int.tryParse(_delayController.text) != _logBolus!.delay ||
                    _setManually != _logBolus!.setManually ||
                    _notesController.text != (_logBolus!.notes ?? ''))))) {
      Dialogs.showCancelConfirmationDialog(
        context: context,
        isNew: _isNew,
        onSave: handleSaveAction,
      );
    } else {
      Navigator.pop(context);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(_isNew ? 'New Bolus' : 'Edit Bolus'),
      ),
      drawer: const Navigation(currentLocation: LogBolusDetailScreen.routeName),
      body: SingleChildScrollView(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: <Widget>[
            FormWrapper(
              formState: _logBolusForm,
              fields: [
                TextFormField(
                  decoration: const InputDecoration(
                    labelText: 'Bolus Units',
                    suffixText: ' U',
                  ),
                  controller: _unitsController,
                  onChanged: (_) {
                    setState(() {
                      _setManually = true;
                    });
                  },
                  keyboardType:
                      const TextInputType.numberWithOptions(decimal: true),
                ),
                BooleanFormField(
                  value: _setManually,
                  label: 'set manually',
                  onChanged: (value) {
                    setState(() {
                      _setManually = value;
                    });
                  },
                ),
                Row(
                  children: [
                    Expanded(
                      child: RadioListTile(
                          title: const Text('for glucose'),
                          groupValue: _bolusType,
                          value: BolusType.glucose,
                          onChanged: (_) {
                            setState(() {
                              _bolusType = BolusType.glucose;
                            });
                          }),
                    ),
                    Expanded(
                      child: RadioListTile(
                          title: const Text('for meal'),
                          groupValue: _bolusType,
                          value: BolusType.meal,
                          onChanged: (value) {
                            setState(() {
                              _bolusType = BolusType.meal;
                            });
                          }),
                    ),
                  ],
                ),
                Column(
                  children: _bolusType == BolusType.glucose
                      ? [
                          Row(
                            children: glucoseMeasurement ==
                                        GlucoseMeasurement.mgPerDl ||
                                    glucoseDisplayMode ==
                                        GlucoseDisplayMode.both ||
                                    glucoseDisplayMode ==
                                        GlucoseDisplayMode.bothForDetail
                                ? [
                                    Expanded(
                                      child: Padding(
                                        padding:
                                            const EdgeInsets.only(right: 5.0),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Current',
                                            suffixText: 'mg/dl',
                                          ),
                                          controller: _mgPerDlCurrentController,
                                          onChanged: (_) => onChangeGlucose(
                                              calculateFrom:
                                                  GlucoseMeasurement.mgPerDl),
                                          keyboardType: const TextInputType
                                              .numberWithOptions(),
                                        ),
                                      ),
                                    ),
                                    Expanded(
                                      child: Padding(
                                        padding: const EdgeInsets.symmetric(
                                            horizontal: 5.0),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Target',
                                            suffixText: 'mg/dl',
                                          ),
                                          controller: _mgPerDlTargetController,
                                          onChanged: (_) => onChangeGlucose(
                                              calculateFrom:
                                                  GlucoseMeasurement.mgPerDl),
                                          keyboardType: const TextInputType
                                              .numberWithOptions(),
                                        ),
                                      ),
                                    ),
                                    Expanded(
                                      child: Padding(
                                        padding:
                                            const EdgeInsets.only(left: 5.0),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Correction',
                                            suffixText: 'mg/dl',
                                          ),
                                          controller:
                                              _mgPerDlCorrectionController,
                                          readOnly: true,
                                        ),
                                      ),
                                    ),
                                    glucoseDisplayMode ==
                                                GlucoseDisplayMode.both ||
                                            glucoseDisplayMode ==
                                                GlucoseDisplayMode.bothForDetail
                                        ? IconButton(
                                            onPressed: () => onChangeGlucose(
                                                calculateFrom:
                                                    GlucoseMeasurement
                                                        .mmolPerL),
                                            icon: const Icon(Icons.calculate),
                                          )
                                        : Container(),
                                  ]
                                : [],
                          ),
                          Row(
                            children: glucoseMeasurement ==
                                        GlucoseMeasurement.mmolPerL ||
                                    glucoseDisplayMode ==
                                        GlucoseDisplayMode.both ||
                                    glucoseDisplayMode ==
                                        GlucoseDisplayMode.bothForDetail
                                ? [
                                    Expanded(
                                      child: Padding(
                                        padding:
                                            const EdgeInsets.only(right: 5),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Current',
                                            suffixText: 'mmol/l',
                                          ),
                                          controller:
                                              _mmolPerLCurrentController,
                                          onChanged: (_) => onChangeGlucose(
                                              calculateFrom:
                                                  GlucoseMeasurement.mmolPerL),
                                          keyboardType: const TextInputType
                                              .numberWithOptions(),
                                        ),
                                      ),
                                    ),
                                    Expanded(
                                      child: Padding(
                                        padding: const EdgeInsets.symmetric(
                                            horizontal: 5.0),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Target',
                                            suffixText: 'mmol/l',
                                          ),
                                          controller: _mmolPerLTargetController,
                                          onChanged: (_) => onChangeGlucose(
                                              calculateFrom:
                                                  GlucoseMeasurement.mmolPerL),
                                          keyboardType: const TextInputType
                                              .numberWithOptions(),
                                        ),
                                      ),
                                    ),
                                    Expanded(
                                      child: Padding(
                                        padding:
                                            const EdgeInsets.only(left: 5.0),
                                        child: TextFormField(
                                          decoration: const InputDecoration(
                                            labelText: 'Correction',
                                            suffixText: 'mmol/l',
                                          ),
                                          controller:
                                              _mmolPerLCorrectionController,
                                          readOnly: true,
                                        ),
                                      ),
                                    ),
                                    glucoseDisplayMode ==
                                                GlucoseDisplayMode.both ||
                                            glucoseDisplayMode ==
                                                GlucoseDisplayMode.bothForDetail
                                        ? IconButton(
                                            onPressed: () => onChangeGlucose(
                                                calculateFrom:
                                                    GlucoseMeasurement.mgPerDl),
                                            icon: const Icon(Icons.calculate),
                                          )
                                        : Container(),
                                  ]
                                : [],
                          ),
                        ]
                      : [
                          AutoCompleteDropdownButton<LogMeal>(
                            selectedItem: _meal,
                            label: 'Meal',
                            items: _logMeals,
                            onChanged: (value) {
                              if (value != null) {
                                onSelectMeal(value);
                              }
                            },
                          ),
                          TextFormField(
                            decoration: InputDecoration(
                              labelText: 'Carbs',
                              suffixText: nutritionMeasurement ==
                                      NutritionMeasurement.grams
                                  ? 'g'
                                  : nutritionMeasurement ==
                                          NutritionMeasurement.ounces
                                      ? 'oz'
                                      : '',
                            ),
                            controller: _carbsController,
                            onChanged: (_) => onChangeCarbs(),
                            keyboardType: const TextInputType.numberWithOptions(
                                decimal: true),
                          ),
                        ],
                ),
                TextFormField(
                  decoration: const InputDecoration(
                    labelText: 'Delayed Bolus Duration',
                    suffixText: ' min',
                  ),
                  controller: _delayController,
                  keyboardType: const TextInputType.numberWithOptions(),
                ),
                TextFormField(
                  controller: _notesController,
                  decoration: const InputDecoration(
                    labelText: 'Notes',
                    alignLabelWithHint: true,
                  ),
                  keyboardType: TextInputType.multiline,
                ),
              ],
            ),
          ],
        ),
      ),
      bottomNavigationBar: DetailBottomRow(
        onCancel: handleCancelAction,
        onSave: _isSaving ? null : handleSaveAction,
      ),
    );
  }
}