checker/lib/screens/purchase.dart

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'dart:convert';
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/network.dart';
import 'package:checker/base_state.dart';
import 'package:checker/screens/purchase_success.dart';

/// Экран проведения покупки.
class PurchaseScreen extends StatefulWidget {

  PurchaseScreen(this.user, this.card);

  final String user;
  final String card;

  @override State createState() => new PurchaseScreenState<PurchaseScreen>(user, card);
}

class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {

  /// Объект, помогающий вручную изменять введенный пользователем текст.
  /// Используется для форматирования введенных пользователем данных
  /// (удаляет запрещенные символы до их отображаения).
  TextEditingController controller = new TextEditingController();

  PurchaseScreenState(String userString, String card) {
    this.user = JSON.decode(userString);
    this.card = card;
  }

  @override void onStart() {
    getLoyalty(user['loyalty_url']);
  }

  bool purchaseInProgress = false;
  Map user;
  String card = '';
  String loyalty = '';

  @override Widget getScreenContent() {
    return new Column(
        children: <Widget>[new Expanded(child: new ListView(children: <Widget>[
          getValueWithDescription(StringsLocalization.userName(), user['first_name'] == null ? '' : user['first_name']),
          getValueWithDescription(StringsLocalization.card(), card),
          getValueWithDescription(StringsLocalization.reward(), loyalty),
          getHintLabel(),
          getInputField(),
          wrapButton(getScreenMargins(36.0), getCompleteButton()),
          wrapButton(getScreenMargins(24.0), getScanButton(context, StringsLocalization.scan(), Resources.getPrimaryColor(app)))
        ]))]);
  }

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

  getCompleteButton() {
    return buildRaisedButton(StringsLocalization.completePurchase(), () => onPurchaseClick());
  }

  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(context, app, helper)),
        decoration: new BoxDecoration(
            border: new Border.all(color: Resources.getButtonColor(app), width: 1.0),
            borderRadius: new BorderRadius.all(new Radius.circular(4.0))));
  }

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

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

  @override getMenuButtons() {
    return <Widget>[getFaqButton(), getLogoutButton()];
  }

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

  getLoyalty(String url) async {

    if (await platform.invokeMethod('isOnline')) {

      String token = await helper.getToken();

      var headers = {
        'DM-Authorization': 'dmapptoken $appToken',
        'Authorization': 'dmtoken ${token}'
      };

      httpClient.get(url, headers: headers).then((response) {

        print(response.body);

        Map bonuses = JSON.decode(response.body);
        String type = bonuses['type'];
        setState(() {
          if (type == 'amount') {
            this.loyalty = '${user['discount']}%';
          } else {
            List amountToBonus = bonuses['amount_to_bonus'];
            double loyalityVal = (double.parse(amountToBonus[1]) / amountToBonus[0]) * 100;
            this.loyalty = '${loyalityVal.toStringAsFixed(0)}%';
          }
        });
      }).catchError((error) {
        print(error.toString());
      });
    }
  }

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

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

  _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);
      }
    }
    return sumTotal.toStringAsFixed(2);
  }

  onPurchaseClick() {
    String val = _parseSum(controller.text);
    showDialog(context: context, child: new AlertDialog(
        title: new Text(StringsLocalization.confirmation()),
        content: new Text(StringsLocalization.confirmPurchase(val)),
        actions: <Widget>[
          new FlatButton(
            child: new Text(StringsLocalization.no()),
            onPressed: () {
              Navigator.of(context).pop();
            },
          ),
          new FlatButton(
            child: new Text(StringsLocalization.yes()),
            onPressed: () {
              purchase(val);
            },
          )
        ]));
  }

  purchase(String sumTotal) async {
    if (await platform.invokeMethod('isOnline')) {
      if (!purchaseInProgress) {
        purchaseInProgress = true;

        String token = await helper.getToken();
        helper.getMerchantID().then((result) {

          String url = user['purchases_url'];

          var body = {
            'doc_id': result,
            'curr_iso_code': '643',
            'commit': 'true',
            'sum_total': sumTotal
          };

          var headers = {
            'DM-Authorization': 'dmapptoken $appToken',
            'Authorization': 'dmtoken ${token}'
          };

          httpClient.post(url, body: body, headers: headers).then((response) {

            print(response.body);
            helper.close().then((_) {
              Navigator.of(context).pop();
              pushRoute(context, new PurchaseSuccessScreen(sumTotal, user['first_name'] == null ? '' : user['first_name']));
            });

          }).catchError((error) {
            purchaseInProgress = false;
            print(error.toString());
          });
        });
      }
    }
  }
}