checker/lib/screens/purchase_sum.dart

import 'dart:convert';

import 'package:checker/base/base_screen.dart';
import 'package:checker/db.dart';
import 'package:checker/screens/purchase.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:http/http.dart';
import 'dart:core';

import 'package:checker/resources.dart';
import 'package:checker/strings.dart';
import 'package:checker/common.dart';
import 'package:checker/consts.dart';
import 'package:checker/base/base_state.dart';
import 'package:checker/network.dart';

/// Экран ввода суммы покупки
class PurchaseSumScreen extends BaseScreen {
  PurchaseSumScreen(helper, app, this.token) : super(helper, app);

  final String token;

  @override
  State createState() =>
      new PurchaseSumScreenState<PurchaseSumScreen>(helper, app);
}

class PurchaseSumScreenState<T> extends BaseState<PurchaseSumScreen> {
  TextEditingController _sumController = new TextEditingController();

  bool isAutomaticallyImplyLeading() => false;

  PurchaseSumScreenState(SqliteHelper helper, String app) : super(helper, app);

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

  @override
  Widget build(BuildContext ctx) {
    return getMainWidget();
  }

  @override
  Widget getScreenContent() => Column(
        children: <Widget>[
          getHintLabel(),
          getInputField(),
          wrapButton(
              _getScreenMargins(24.0),
              getScanButton(context, StringsLocalization.scan(),
                  Resources.getPrimaryColor(app)))
        ],
      );

  EdgeInsets _getScreenMargins(double top) {
    double side = 42.0;
    return new EdgeInsets.only(top: top, left: side, right: side);
  }

  Widget getScanButton(BuildContext context, String title, Color textColor) {
    return new Container(
        height: buttonHeight,
        child: new FlatButton(
            child: new Text(title, style: new TextStyle(color: textColor)),
            onPressed: () => _startScanner()),
        decoration: new BoxDecoration(
            border: new Border.all(
                color: Resources.getButtonColor(app), width: 1.0),
            borderRadius: new BorderRadius.all(new Radius.circular(4.0))));
  }

  void _startScanner() {
    platform.invokeMethod('getEndpoint').then((url) {
      platform.invokeMethod('getAppToken').then((appToken) {
        Map<String, String> args = StringsLocalization.strings;
        args['token'] = widget.token;
        args['url'] = url;
        args['appToken'] = appToken;
        args['localeCode'] = StringsLocalization.localeCode;
        args['color'] = Resources.getPrimaryColor(app).value.toString();
        platform.invokeMethod('startScanner', args).then((result) {
          _processResult(result);
        });
      });
    });
  }

  @override
  String getTitle() {
    return StringsLocalization.sum();
  }

  @override
  getHintString() {
    return StringsLocalization.sum();
  }

  @override
  getTextWidget() {
    return new TextField(
        keyboardType: TextInputType.number,
        decoration: new InputDecoration.collapsed(
            hintText: getHintString(),
            hintStyle: new TextStyle(color: greyTextColor, fontSize: 16.0)),
        controller: _sumController,
        onSubmitted: (String text) {
          setState(() {
            _sumController.text = _parseSum(text);
          });
        },
        textAlign: TextAlign.center);
  }

  String _cleanupNumber(String text) {
    String tmp = text
        .replaceAll(' ', '')
        .replaceAll('-', '')
        .replaceAll(',', '.')
        .replaceAll('..', '.');

    while (tmp.indexOf('..') != -1) {
      tmp = tmp.replaceAll('..', '.');
    }
    return tmp;
  }

  String _parseSum(String input) {
    num sumTotal = 0.0;
    String text = _cleanupNumber(input);

    try {
      sumTotal = num.parse(text);
    } catch (exception) {
      print(exception);
      try {
        int idx = text.indexOf('.');
        String integerPart = text.substring(0, idx);
        String fractionalPart = text.substring(idx + 1, text.length);
        if (fractionalPart.length > 2) {
          fractionalPart = fractionalPart.substring(0, 2);
        }
        return '$integerPart.$fractionalPart';
      } catch (exception) {
        print(exception);
      }
    }
    print(sumTotal.toStringAsFixed(2));
    return sumTotal.toStringAsFixed(2);
  }

  void _processResult(result) {
    if (result is List) {
      final String user = result[0] as String;
      final String card = result[1] as String;
      Navigator.of(context).push(new MaterialPageRoute(builder: (context) {
        String sum = _parseSum(_sumController.text);
        _sumController.text = "";
        return PurchaseScreen(helper, app, user, card, sum);
      }));
    }
  }

  void _subscribe() async {
    platform.setMethodCallHandler((MethodCall call) async {
      if (call.method == 'findUser') {
        try {
          Response userResponse;

          switch (call.arguments[1]) {
            case 'card':
              userResponse = await getUserByCard(call.arguments[0], widget.token);
              break;
            case 'phone':
              userResponse = await getUserByPhone(call.arguments[0], widget.token);
              break;
          }

          if (userResponse != null) {
            print('I have user in method handler!');
            List<dynamic> users = json.decode(userResponse.body);
            if (users.length > 0) {
              return json.encode(users[0]);
            } else {
              throw new FlutterError("Users not found");
            }
          } else {
            throw new FlutterError("Users not found");
          }
        } catch (error) {
          print(error.toString());
          throw new FlutterError("Users not found");
        }
      } else if (call.method == 'scanSuccess') {
        _processResult(call.arguments);
      }
    });
  }
}