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 Sony.Filtr.Contracts.Abstractions;
using Sony.Filtr.Contracts.Entities;
using Sony.Filtr.Utility;

namespace Sony.Filtr.YouTube.Api
{
    public class AuthenticatedYoutubeApi : YouTubeApi
    {
        public AuthenticatedYoutubeApi(ServiceAccount serviceAccount, IServiceAccountManager serviceAccountManager, GoogleOAuth2Api googleOAuth2Api, IRateLimiter rateLimiter)
            : base(BuildAuthenticatedClient(serviceAccount, serviceAccountManager, googleOAuth2Api, rateLimiter))
        {
        }

        private static HttpClient BuildAuthenticatedClient(ServiceAccount serviceAccount, IServiceAccountManager serviceAccountManager, GoogleOAuth2Api googleOAuth2Api, IRateLimiter rateLimiter)
        {
            var rateLimitedHandler = new RateLimitedHttpMessageHandler(new HttpClientHandler() {AutomaticDecompression = DecompressionMethods.GZip}, rateLimiter);
            var youtubeOAuthMessageHandler = new YouTubeOAuthHttpMessageHandler(serviceAccount, serviceAccountManager, googleOAuth2Api, rateLimitedHandler);
            HttpClient client = new HttpClient(youtubeOAuthMessageHandler);
            client.DefaultRequestHeaders.AcceptEncoding.Add(new StringWithQualityHeaderValue("gzip"));
            client.DefaultRequestHeaders.UserAgent.ParseAdd("Filtr/1.0 (gzip)");
            
            return client;
        }

        public async Task AddVideoToPlaylistAsync(string playlistId, Id videoId, int? position = null)
        {
            var url = new Url("https://www.googleapis.com/youtube/v3/playlistItems");
            url.SetQueryParam("part", "snippet");

            var response = await GetDefaultClient().PostAsJsonAsync(url, new
            {
                snippet = new
                {
                    playlistId = playlistId,
                    resourceId = new
                    {
                        videoId = videoId.videoId,
                        kind = "youtube#video"
                    },
                    position = position
                }
            });

            if (!response.IsSuccessStatusCode)
            {
                throw YoutubeApiException.FromHttpResponseMessage(response, "Could not add videos to youtube playlists");
            }
        }

        public async Task AddVideosToPlaylistAsync(string playlistId, List<string> videoIds,
            CancellationToken cancellationToken)
        {
            foreach (var videoId in videoIds)
            {
                var youtubeId = new Id() {videoId = videoId};

                await AddVideoToPlaylistAsync(playlistId, youtubeId);
            }
        }
        
        public async Task DeletePlaylistItemsAsync(PlaylistItem playlistItem)
        {
            if (playlistItem == null)
                return;

            var url = new Url("https://www.googleapis.com/youtube/v3/playlistItems");
            url.SetQueryParam("id", playlistItem.id);

            var response = await GetDefaultClient().DeleteAsync(url);

            if (!response.IsSuccessStatusCode)
            {
                throw YoutubeApiException.FromHttpResponseMessage(response, "Could not delete playlists items in youtube playlist");
            }
        }

        public async Task DeletePlaylistItemsAsync(List<PlaylistItem> playlistItems)
        {
            if (playlistItems == null || !playlistItems.Any())
                return;

            foreach (var playlistItem in playlistItems)
            {
                await DeletePlaylistItemsAsync(playlistItem);
            }
        }

        public async Task UpdatePlaylistItemAsync(PlaylistItem playlistItem)
        {
            if (playlistItem == null)
                return;

            var simpleItem = new SimplePlaylistItem(playlistItem);

            var url = new Url("https://www.googleapis.com/youtube/v3/playlistItems");
            url.SetQueryParam("part", "snippet");

            var response = await GetDefaultClient().PutAsJsonAsync(url, simpleItem);

            if (!response.IsSuccessStatusCode)
            {
                throw YoutubeApiException.FromHttpResponseMessage(response, "Could not update playlist item in youtube playlist.");
            }
        }

        public async Task UpdatePlaylistAsync(Playlist playlist)
        {
            if (playlist == null)
                return;

            var url = new Url("https://www.googleapis.com/youtube/v3/playlists");
            url.SetQueryParam("part", "snippet");

            var response = await GetDefaultClient().PutAsJsonAsync(url, playlist);

            if (!response.IsSuccessStatusCode)
            {
                throw YoutubeApiException.FromHttpResponseMessage(response, "Could not update playlist");
            }
        }

        public async Task<ChannelResponse> GetMyChannelsAsync()
        {
            var url = new Url("https://www.googleapis.com/youtube/v3/channels");
            url.SetQueryParam("part", "snippet");
            url.SetQueryParam("mine", "true");

            var response = await GetDefaultClient().GetAsync(url);
            var playlistResponse = await response.Content.ReadAsAsync<ChannelResponse>();
            return playlistResponse;
        }
    }
}