using System;
using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using Microsoft.Identity.Client;
using System.Net.Http.Headers;
using System.Net.Http;

namespace AzureFunctionMSAL
{
    public static class ConnectMSAL
    {
       

        [FunctionName("MSALFunction")]

        // change get or post based on your scenario

        public static async Task<IActionResult> Run(
            [HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
            ILogger log)
        {
            log.LogInformation("C# HTTP trigger function processed a request.");

            string contactEmail = req.Query["eamil"];
            string contacts = string.Empty;
            string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
            dynamic data = JsonConvert.DeserializeObject(requestBody);
            contactEmail = contactEmail ?? data?.email;


            // MSAL Authentication
            string clientId = "*********583";
            string secret = "zDC******";
            string[] scope = new string[] { "https://******.crm.dynamics.com/.default" };
            string webAPI = " https://***.crm.dynamics.com/api/data/v9.1/";
            string authority = "https://login.microsoftonline.com/69e9641e-4be0-4f4c-9ae4-06fdc1160c34";

            var clientApp = ConfidentialClientApplicationBuilder.Create(clientId: clientId)
            .WithClientSecret(clientSecret: secret)
            .WithAuthority(new Uri(authority))
            .Build();

            try
            {
                AuthenticationResult authResult = await clientApp.AcquireTokenForClient(scope).ExecuteAsync();

    // WEB API
                var httpClient = new HttpClient();
                httpClient.DefaultRequestHeaders.Add("OData-MaxVersion", "4.0");
                httpClient.DefaultRequestHeaders.Add("OData-Version", "4.0");
                httpClient.Timeout = new TimeSpan(0, 2, 0);
                httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
                httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", authResult.AccessToken);
                httpClient.BaseAddress = new Uri(webAPI);
                var queryOptions = "contacts?$select=fullname,mobilephone&$filter=emailaddress1 eq '" + contactEmail + "'";
                var response =  httpClient.GetAsync(queryOptions).Result;
                
                if (response.IsSuccessStatusCode)
                {
                    var contactsresult = response.Content.ReadAsStringAsync().Result;
                    contacts = contactsresult;
                    log.LogInformation("webapi executed");
               
                }

            }
            catch (Exception ex)
            {
                // log error 
                string errorMessage = ex.Message;
                log.LogError(errorMessage);
                //response
                return new BadRequestObjectResult(JsonConvert.SerializeObject("an error occured while retriving contacts:"));
            }



            //
            string responseMessage = "WEB API Response: " + contacts;

            return new OkObjectResult(responseMessage);
        }
    }
}