import 'package:flutter/material.dart';
import 'package:http/http.dart as http;
import 'dart:convert';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State {
  var response;
  final apiUrl = 'http://100032.pythonanywhere.com/api/targeted_population/';

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

  Future fetchData() async {
    final Map requestData = {
      'database_details': {
        'database_name': 'mongodb',
        'collection': 'test',
        'database': 'Bangalore',
        'fields': ["LENGTH"],
      },
      'number_of_variable': 1,
      'time_input': {
        'column_name': 'Date',
        'split': 'week',
        'period': 'life_time',
        'start_point': '2021/01/08',
        'end_point': '2021/01/25',
      },
      'stages': [
        {
          'data_type': 1,
          'm_or_A_selction': 'maximum_point',
          'm_or_A_value': 500,
          'error': 40,
          'r': 100,
          'start_point': 0,
          'end_point': 700,
          'a': 2,
        },
      ],
      'distribution_input': {
        'normal': 1,
        'poisson': 1,
        'binomial': 1,
        'bernoulli': 0,
      },
      'bernoulli': {
        'error_size': 0.167,
        'test_number': 7,
        'selection_start_point': 500,
        'items_to_be_selected': 600,
      },
      'binomial': {
        'number_of_variable': 13,
        'split_choice': 'simple',
        'split_decision': 'Eliminate',
        'user_choice_value': 43,
        'function': '>',
        'marginal_error': '0',
        'error': 20,
      },
    };

    final headers = {'content-type': 'application/json'};

    final http.Response apiResponse = await http.post(
      Uri.parse(apiUrl),
      body: jsonEncode(requestData),
      headers: headers,
    );

    if (apiResponse.statusCode == 200) {
      setState(() {
        response = apiResponse.body;
      });
    } else {
      print('Request failed with status code: ${apiResponse.statusCode}');
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Flutter App')),
      body: Center(
        child: response != null
            ? Text(response)
            : CircularProgressIndicator(),
      ),
    );
  }
}