using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading;
using System.Threading.Tasks;
using Flurl;
using Newtonsoft.Json;
using Sony.Filtr.Contracts.Abstractions;
using Sony.Filtr.Contracts.Entities;
using Sony.Filtr.SoundCloud.Model;

namespace Sony.Filtr.SoundCloud
{
    public class SoundCloudAuthorizationHttpMessageHandler : DelegatingHandler
    {
        private ServiceAccount _serviceAccount;
        private readonly IServiceAccountManager _serviceAccountManager;
        private readonly string _clientId;
        private readonly string _clientSecret;

        public SoundCloudAuthorizationHttpMessageHandler(ServiceAccount serviceAccount, IServiceAccountManager serviceAccountManager, string clientId, string clientSecret, HttpMessageHandler httpMessageHandler)
            : base(httpMessageHandler)
        {
            _serviceAccount = serviceAccount;
            _serviceAccountManager = serviceAccountManager;
            _clientId = clientId;
            _clientSecret = clientSecret;
        }

        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            var url = new Url(request.RequestUri.ToString());
            url.SetQueryParam("oauth_token", _serviceAccount.AccessToken);
            request.RequestUri = new Uri(url);

            var response = await base.SendAsync(request, cancellationToken);
            if (response.StatusCode == HttpStatusCode.Unauthorized)
            {
                //Our access code be old, try and refresh
                var refreshedAccessToken = await RequestRefreshedAccessToken(_serviceAccount.RefreshToken);
                if (refreshedAccessToken == null || string.IsNullOrWhiteSpace(refreshedAccessToken.access_token))
                {
                    throw new SoundCloudException("Could not get access token by refresh token", HttpMethod.Post, HttpStatusCode.Unauthorized);
                }

                _serviceAccount = SaveAccessToken(_serviceAccount, refreshedAccessToken);

                //Try request once more with updated access token
                url.SetQueryParam("oauth_token", _serviceAccount.AccessToken);
                request.RequestUri = new Uri(url);
                response = await base.SendAsync(request, cancellationToken);
            }
            return response;
        }

        private ServiceAccount SaveAccessToken(ServiceAccount serviceAccount, SoundCloudAuthResponse refreshedAccessToken)
        {
            _serviceAccount.UpdatedDate = DateTime.Now;
            _serviceAccount.AccessToken = refreshedAccessToken.access_token;
            _serviceAccount.AccessTokenExpiry = refreshedAccessToken.expires_in;
            var updatedServiceAccount = _serviceAccountManager.SaveServiceAccount(serviceAccount);
            return updatedServiceAccount;
        }

        private async Task<SoundCloudAuthResponse> RequestRefreshedAccessToken(string refreshToken)
        {
            var url = $"https://api.soundcloud.com/oauth2/token";

            var client = new HttpClient();

            var formDictionary = new Dictionary<string, string>()
                {
                    { "client_id", _clientId },
                    { "client_secret", _clientSecret},
                    { "grant_type", "refresh_token" },
                    { "refresh_token", refreshToken },
                    {"redirect_uri", "http://adminapi.filtr.local.circuit.se/serviceAccounts/soundcloudcallback" }
                };

            var response = await client.PostAsync(url, new FormUrlEncodedContent(formDictionary));

            var soundCloudResponseString = await response.Content.ReadAsStringAsync();
            return JsonConvert.DeserializeObject<SoundCloudAuthResponse>(soundCloudResponseString);
        }
    }
}