using System;

using System.Collections.Generic;

using System.Data.SqlClient;

using System.Threading.Tasks;

​

namespace CodeReview

{

    public class PersonController

    {

        // returns a JSON string representing a person object

        public string Get(string name)

        {

            var dataProvider = new PersonDataProvider();

            return ConvertToJson(dataProvider.GetPerson(name));

        }

        public string GetAllWithManager()

        {

            var dataProvider = new PersonDataProvider();

            var persons = dataProvider.GetAllPersonAsyn().Result;

            foreach (var item in persons)

            {

                item.Manager = dataProvider.GetManager(item.ManagerId).Result;

            }

​

            return ConvertToJson(persons);

        }

​

        private string ConvertToJson(object obj)

        {

            throw new NotImplementedException();

        }

    }

​

    public class PersonDataProvider

    {

        SqlConnection conn = new SqlConnection();

​

        public Person GetPerson(string name)

        {

            conn.Open();

​

            SqlCommand sc = new SqlCommand($"Select * from Person where name = '{name}'");

            var reader = sc.ExecuteReader();

            // read from data reader

            return new Person(); // assume this line returns the result

        }

​

        public async Task<Person> GetPersonAsyn(string name)

        {

            await conn.OpenAsync();

​

            SqlCommand sc = new SqlCommand($"Select * from Person where name = '{name}'");

            var reader = await sc.ExecuteReaderAsync();

            // read from data reader

            return new Person(); // assume this line returns the result

        }

​

        public async Task<List<Person>> GetAllPersonAsyn()

        {

            await conn.OpenAsync();

​

            SqlCommand sc = new SqlCommand($"Select * from Person");

            var reader = await sc.ExecuteReaderAsync();

            // read from data reader

            return new List<Person>(); // assume this line returns the result

        }

​

        public async Task<Manager> GetManager(int id)

        {

            SqlCommand sc = new SqlCommand($"Select * from Manager where Id = {id}");

            var reader = await sc.ExecuteReaderAsync();

            // read from data reader

            return new Manager(); // assume this line returns the result

        }

    }

​

    public class Person

    {

        public int Id { get; set; }

        public string Name { get; set; }

        public int ManagerId { get; set; }

        public Manager Manager { get; set; }

    }

​

    public class Manager

    {

        public string Name { get; set; }

    }

}