using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using MediaBrowser.Common.Net;
using MediaBrowser.Controller.Entities;
using MediaBrowser.Controller.Entities.TV;
using MediaBrowser.Controller.Providers;
using MediaBrowser.Model.Entities;
using MediaBrowser.Model.Providers;
using Microsoft.Extensions.Logging;
using TvDbSharper;
using TvDbSharper.Dto;

namespace MediaBrowser.Providers.TV.TheTVDB
{

    /// <summary>
    /// Class RemoteEpisodeProvider
    /// </summary>
    public class TvdbEpisodeProvider : IRemoteMetadataProvider<Episode, EpisodeInfo>, IHasOrder
    {
        private readonly IHttpClient _httpClient;
        private readonly ILogger _logger;
        private readonly TvDbClientManager _tvDbClientManager;

        public TvdbEpisodeProvider(IHttpClient httpClient, ILogger<TvdbEpisodeProvider> logger, TvDbClientManager tvDbClientManager)
        {
            _httpClient = httpClient;
            _logger = logger;
            _tvDbClientManager = tvDbClientManager;
        }

        public async Task<IEnumerable<RemoteSearchResult>> GetSearchResults(EpisodeInfo searchInfo, CancellationToken cancellationToken)
        {
            var list = new List<RemoteSearchResult>();

            // The search query must either provide an episode number or date
            if (!searchInfo.IndexNumber.HasValue || !searchInfo.PremiereDate.HasValue)
            {
                return list;
            }

            if (TvdbSeriesProvider.IsValidSeries(searchInfo.SeriesProviderIds))
            {
                try
                {
                    var episodeTvdbId = searchInfo.GetProviderId(MetadataProviders.Tvdb);
                    if (string.IsNullOrEmpty(episodeTvdbId))
                    {
                        searchInfo.SeriesProviderIds.TryGetValue(MetadataProviders.Tvdb.ToString(),
                            out var seriesTvdbId);
                        episodeTvdbId = await _tvDbClientManager
                            .GetEpisodeTvdbId(searchInfo, searchInfo.MetadataLanguage, cancellationToken)
                            .ConfigureAwait(false);
                        if (string.IsNullOrEmpty(episodeTvdbId))
                        {
                            _logger.LogError("Episode {SeasonNumber}x{EpisodeNumber} not found for series {SeriesTvdbId}",
                                searchInfo.ParentIndexNumber, searchInfo.IndexNumber, seriesTvdbId);
                            return list;
                        }
                    }

                    var episodeResult = await _tvDbClientManager.GetEpisodesAsync(Convert.ToInt32(episodeTvdbId),
                        searchInfo.MetadataLanguage, cancellationToken).ConfigureAwait(false);
                    var metadataResult = MapEpisodeToResult(searchInfo, episodeResult.Data);

                    if (metadataResult.HasMetadata)
                    {
                        var item = metadataResult.Item;

                        list.Add(new RemoteSearchResult
                        {
                            IndexNumber = item.IndexNumber,
                            Name = item.Name,
                            ParentIndexNumber = item.ParentIndexNumber,
                            PremiereDate = item.PremiereDate,
                            ProductionYear = item.ProductionYear,
                            ProviderIds = item.ProviderIds,
                            SearchProviderName = Name,
                            IndexNumberEnd = item.IndexNumberEnd
                        });
                    }
                }
                catch (TvDbServerException e)
                {
                    _logger.LogError(e, "Failed to retrieve episode with id {TvDbId}", searchInfo.IndexNumber);
                }
            }

            return list;
        }

        public string Name => "TheTVDB";

        public async Task<MetadataResult<Episode>> GetMetadata(EpisodeInfo searchInfo, CancellationToken cancellationToken)
        {
            var result = new MetadataResult<Episode>
            {
                QueriedById = true
            };

            if (TvdbSeriesProvider.IsValidSeries(searchInfo.SeriesProviderIds) &&
                (searchInfo.IndexNumber.HasValue || searchInfo.PremiereDate.HasValue))
            {
                var tvdbId = searchInfo.GetProviderId(MetadataProviders.Tvdb);
                try
                {
                    if (string.IsNullOrEmpty(tvdbId))
                    {
                        tvdbId = await _tvDbClientManager
                            .GetEpisodeTvdbId(searchInfo, searchInfo.MetadataLanguage, cancellationToken)
                            .ConfigureAwait(false);
                        if (string.IsNullOrEmpty(tvdbId))
                        {
                            _logger.LogError("Episode {SeasonNumber}x{EpisodeNumber} not found for series {SeriesTvdbId}",
                                 searchInfo.ParentIndexNumber, searchInfo.IndexNumber, tvdbId);
                            return result;
                        }
                    }

                    var episodeResult = await _tvDbClientManager.GetEpisodesAsync(
                        Convert.ToInt32(tvdbId), searchInfo.MetadataLanguage,
                        cancellationToken).ConfigureAwait(false);

                    result = MapEpisodeToResult(searchInfo, episodeResult.Data);
                }
                catch (TvDbServerException e)
                {
                    _logger.LogError(e, "Failed to retrieve episode with id {TvDbId}", tvdbId);
                }
            }
            else
            {
                _logger.LogDebug("No series identity found for {EpisodeName}", searchInfo.Name);
            }

            return result;
        }

        private static MetadataResult<Episode> MapEpisodeToResult(EpisodeInfo id, EpisodeRecord episode)
        {
            var result = new MetadataResult<Episode>
            {
                HasMetadata = true,
                Item = new Episode
                {
                    IndexNumber = id.IndexNumber,
                    ParentIndexNumber = id.ParentIndexNumber,
                    IndexNumberEnd = id.IndexNumberEnd,
                    AirsBeforeEpisodeNumber = episode.AirsBeforeEpisode,
                    AirsAfterSeasonNumber = episode.AirsAfterSeason,
                    AirsBeforeSeasonNumber = episode.AirsBeforeSeason,
                    Name = episode.EpisodeName,
                    Overview = episode.Overview,
                    CommunityRating = (float?)episode.SiteRating,

                }
            };
            result.ResetPeople();

            var item = result.Item;
            item.SetProviderId(MetadataProviders.Tvdb, episode.Id.ToString());
            item.SetProviderId(MetadataProviders.Imdb, episode.ImdbId);

            if (string.Equals(id.SeriesDisplayOrder, "dvd", StringComparison.OrdinalIgnoreCase))
            {
                item.IndexNumber = Convert.ToInt32(episode.DvdEpisodeNumber ?? episode.AiredEpisodeNumber);
                item.ParentIndexNumber = episode.DvdSeason ?? episode.AiredSeason;
            }
            else if (episode.AiredEpisodeNumber.HasValue)
            {
                item.IndexNumber = episode.AiredEpisodeNumber;
            }
            else if (episode.AiredSeason.HasValue)
            {
                item.ParentIndexNumber = episode.AiredSeason;
            }

            if (DateTime.TryParse(episode.FirstAired, out var date))
            {
                // dates from tvdb are UTC but without offset or Z
                item.PremiereDate = date;
                item.ProductionYear = date.Year;
            }

            foreach (var director in episode.Directors)
            {
                result.AddPerson(new PersonInfo
                {
                    Name = director,
                    Type = PersonType.Director
                });
            }

            // GuestStars is a weird list of names and roles
            // Example:
            // 1: Some Actor (Role1
            // 2: Role2
            // 3: Role3)
            // 4: Another Actor (Role1
            // ...
            for (var i = 0; i < episode.GuestStars.Length; ++i)
            {
                var currentActor = episode.GuestStars[i];
                var roleStartIndex = currentActor.IndexOf('(');

                var roles = new List<string> {currentActor.Substring(roleStartIndex + 1)};
                var name = currentActor.Substring(0, roleStartIndex).Trim();

                // Fetch all roles
                for (var j = i + 1; j < episode.GuestStars.Length; ++j)
                {
                    var currentRole = episode.GuestStars[j];
                    var roleEndIndex = currentRole.IndexOf(')');

                    if (roleEndIndex != -1)
                    {
                        roles.Add(currentRole.TrimEnd(')'));
                        // Update the outer index (keep in mind it adds 1 after the iteration)
                        i = j;
                        break;
                    }

                    roles.Add(currentRole);
                }

                result.AddPerson(new PersonInfo
                {
                    Type = PersonType.GuestStar,
                    Name = name,
                    Role = string.Join(", ", roles)
                });
            }

            foreach (var writer in episode.Writers)
            {
                result.AddPerson(new PersonInfo
                {
                    Name = writer,
                    Type = PersonType.Writer
                });
            }

            result.ResultLanguage = episode.Language.EpisodeName;
            return result;
        }

        public Task<HttpResponseInfo> GetImageResponse(string url, CancellationToken cancellationToken)
        {
            return _httpClient.GetResponse(new HttpRequestOptions
            {
                CancellationToken = cancellationToken,
                Url = url
            });
        }

        public int Order => 0;
    }
}