import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:invoiceninja_flutter/constants.dart';
import 'package:invoiceninja_flutter/data/models/entities.dart';
import 'package:invoiceninja_flutter/data/models/invoice_model.dart';
import 'package:invoiceninja_flutter/data/models/payment_model.dart';
import 'package:invoiceninja_flutter/redux/invoice/invoice_selectors.dart';
import 'package:invoiceninja_flutter/redux/client/client_selectors.dart';
import 'package:invoiceninja_flutter/redux/static/static_selectors.dart';
import 'package:invoiceninja_flutter/ui/app/form_card.dart';
import 'package:invoiceninja_flutter/ui/app/forms/date_picker.dart';
import 'package:invoiceninja_flutter/ui/app/forms/decorated_form_field.dart';
import 'package:invoiceninja_flutter/ui/payment/edit/payment_edit_vm.dart';
import 'package:invoiceninja_flutter/ui/app/edit_scaffold.dart';
import 'package:invoiceninja_flutter/utils/completers.dart';
import 'package:invoiceninja_flutter/utils/formatting.dart';
import 'package:invoiceninja_flutter/utils/localization.dart';
import 'package:invoiceninja_flutter/ui/app/entity_dropdown.dart';

class PaymentEdit extends StatefulWidget {
  const PaymentEdit({
    Key key,
    @required this.viewModel,
  }) : super(key: key);

  final PaymentEditVM viewModel;

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

class _PaymentEditState extends State<PaymentEdit> {
  static final GlobalKey<FormState> _formKey =
      GlobalKey<FormState>(debugLabel: '_paymentEdit');

  final _amountController = TextEditingController();
  final _transactionReferenceController = TextEditingController();
  final _privateNotesController = TextEditingController();

  List<TextEditingController> _controllers = [];
  final _debouncer = Debouncer();
  bool autoValidate = false;

  @override
  void didChangeDependencies() {
    _controllers = [
      _amountController,
      _transactionReferenceController,
      _privateNotesController,
    ];

    _controllers.forEach((controller) => controller.removeListener(_onChanged));

    final payment = widget.viewModel.payment;

    _amountController.text = formatNumber(payment.amount, context,
        formatNumberType: FormatNumberType.input);
    _transactionReferenceController.text = payment.transactionReference;
    _privateNotesController.text = payment.privateNotes;
    _controllers.forEach((controller) => controller.addListener(_onChanged));

    super.didChangeDependencies();
  }

  @override
  void dispose() {
    _controllers.forEach((controller) {
      controller.removeListener(_onChanged);
      controller.dispose();
    });

    super.dispose();
  }

  void _onChanged() {
    _debouncer.run(() {
      final payment = widget.viewModel.payment.rebuild((b) => b
        ..amount = parseDouble(_amountController.text)
        ..transactionReference = _transactionReferenceController.text.trim()
        ..privateNotes = _privateNotesController.text.trim());
      if (payment != widget.viewModel.payment) {
        widget.viewModel.onChanged(payment);
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    final viewModel = widget.viewModel;
    final payment = viewModel.payment;
    final localization = AppLocalization.of(context);

    final paymentables = payment.invoices.toList();
    if (paymentables.where((paymentable) => paymentable.isEmpty).isEmpty) {
      paymentables.add(PaymentableEntity());
    }

    return EditScaffold(
      entity: payment,
      title: viewModel.payment.isNew
          ? localization.enterPayment
          : localization.editPayment,
      onCancelPressed: (context) => viewModel.onCancelPressed(context),
      onSavePressed: (context) {
        final bool isValid = _formKey.currentState.validate();

        setState(() {
          autoValidate = !isValid;
        });

        if (!isValid) {
          return;
        }

        viewModel.onSavePressed(context);
      },
      body: Form(
        key: _formKey,
        child: ListView(
          key: ValueKey(viewModel.payment.id),
          children: <Widget>[
            FormCard(
              children: <Widget>[
                if (payment.isNew) ...[
                  EntityDropdown(
                    key: Key('__client_${payment.clientId}__'),
                    entityType: EntityType.client,
                    labelText: AppLocalization.of(context).client,
                    entityId: payment.clientId,
                    autoValidate: autoValidate,
                    validator: (String val) => val.trim().isEmpty
                        ? AppLocalization.of(context).pleaseSelectAClient
                        : null,
                    onSelected: (client) {
                      viewModel.onChanged(payment.rebuild((b) => b
                        ..clientId = client.id
                        ..invoices.clear()));
                    },
                    entityList: memoizedDropdownClientList(
                        viewModel.clientMap, viewModel.clientList),
                  ),
                  DecoratedFormField(
                    controller: _amountController,
                    autocorrect: false,
                    keyboardType:
                        TextInputType.numberWithOptions(decimal: true),
                    label: localization.amount,
                  ),
                ],
                for (var index = 0; index < paymentables.length; index++)
                  PaymentableEditor(
                    key: ValueKey(
                        '__paymentable_${index}_${paymentables[index].id}__'),
                    viewModel: viewModel,
                    paymentable: paymentables[index],
                    index: index,
                    onChanged: () {},
                  ),
                EntityDropdown(
                  key: ValueKey('__payment_type_${payment.typeId}__'),
                  entityType: EntityType.paymentType,
                  entityList: memoizedPaymentTypeList(
                      viewModel.staticState.paymentTypeMap),
                  labelText: localization.paymentType,
                  entityId: payment.typeId,
                  onSelected: (paymentType) => viewModel.onChanged(
                      payment.rebuild((b) => b..typeId = paymentType.id)),
                ),
                DatePicker(
                  validator: (String val) => val.trim().isEmpty
                      ? AppLocalization.of(context).pleaseSelectADate
                      : null,
                  autoValidate: autoValidate,
                  labelText: localization.paymentDate,
                  selectedDate: payment.date,
                  onSelected: (date) {
                    viewModel.onChanged(payment.rebuild((b) => b..date = date));
                  },
                ),
                DecoratedFormField(
                  controller: _transactionReferenceController,
                  label: localization.transactionReference,
                ),
                DecoratedFormField(
                  controller: _privateNotesController,
                  label: localization.privateNotes,
                  keyboardType: TextInputType.multiline,
                  maxLines: 4,
                ),
              ],
            ),
            payment.isNew
                ? FormCard(children: <Widget>[
                    SwitchListTile(
                      activeColor: Theme.of(context).accentColor,
                      title: Text(localization.sendEmail),
                      value: viewModel.prefState.emailPayment,
                      subtitle: Text(localization.emailReceipt),
                      onChanged: (value) => viewModel.onEmailChanged(value),
                    ),
                  ])
                : Container(),
          ],
        ),
      ),
    );
  }
}

class PaymentableEditor extends StatefulWidget {
  const PaymentableEditor({
    Key key,
    @required this.viewModel,
    @required this.paymentable,
    @required this.onChanged,
    @required this.index,
  }) : super(key: key);

  final PaymentEditVM viewModel;
  final PaymentableEntity paymentable;
  final Function onChanged;
  final int index;

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

class _PaymentableEditorState extends State<PaymentableEditor> {
  final _amountController = TextEditingController();
  String _invoiceId = '';
  List<TextEditingController> _controllers = [];

  @override
  void didChangeDependencies() {
    _controllers = [
      _amountController,
    ];

    _controllers.forEach((controller) => controller.removeListener(_onChanged));

    _amountController.text = formatNumber(widget.paymentable.amount, context,
        formatNumberType: FormatNumberType.input);

    _controllers.forEach((controller) => controller.addListener(_onChanged));

    super.didChangeDependencies();
  }

  @override
  void dispose() {
    _controllers.forEach((controller) {
      controller.removeListener(_onChanged);
      controller.dispose();
    });

    super.dispose();
  }

  void _onChanged([String clientId]) {
    final paymentable = widget.paymentable.rebuild((b) => b
      ..invoiceId = _invoiceId
      ..amount = parseDouble(_amountController.text));

    if (paymentable == widget.paymentable || paymentable.isEmpty) {
      return;
    }

    PaymentEntity payment;

    if (widget.index == widget.viewModel.payment.invoices.length) {
      payment =
          widget.viewModel.payment.rebuild((b) => b..invoices.add(paymentable));
    } else {
      payment = widget.viewModel.payment
          .rebuild((b) => b..invoices[widget.index] = paymentable);
    }

    if (clientId != null) {
      payment = payment.rebuild((b) => b..clientId = clientId);
    }

    widget.viewModel.onChanged(payment);
  }

  @override
  Widget build(BuildContext context) {
    final viewModel = widget.viewModel;
    final payment = viewModel.payment;
    final paymentable = widget.paymentable;
    final localization = AppLocalization.of(context);

    return Row(
      children: <Widget>[
        Expanded(
          child: EntityDropdown(
            key: Key('__invoice_${payment.clientId}__'),
            entityType: EntityType.invoice,
            labelText: AppLocalization.of(context).invoice,
            entityId: paymentable.invoiceId,
            entityList: memoizedDropdownInvoiceList(
                widget.viewModel.invoiceMap,
                widget.viewModel.clientMap,
                widget.viewModel.invoiceList,
                payment.clientId),
            onSelected: (selected) {
              final invoice = selected as InvoiceEntity;
              _amountController.text = formatNumber(invoice.balance, context,
                  formatNumberType: FormatNumberType.input);
              _invoiceId = invoice.id;
              _onChanged(invoice.clientId);
            },
          ),
        ),
        SizedBox(
          width: kTableColumnGap,
        ),
        Expanded(
          child: DecoratedFormField(
            controller: _amountController,
            label: localization.applied,
          ),
        ),
        SizedBox(
          width: kTableColumnGap,
        ),
        IconButton(
          icon: Icon(Icons.clear),
          tooltip: localization.remove,
          onPressed: paymentable.isEmpty
              ? null
              : () {
                  viewModel.onChanged(payment
                      .rebuild((b) => b..invoices.removeAt(widget.index)));
                },
        ),
      ],
    );
  }
}