using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using ErsatzTV.Core;
using ErsatzTV.Core.Domain;
using ErsatzTV.Core.Emby;
using ErsatzTV.Core.Interfaces.Emby;
using ErsatzTV.Core.Interfaces.Metadata;
using ErsatzTV.Infrastructure.Emby.Models;
using LanguageExt;
using Microsoft.Extensions.Logging;
using Refit;
using static LanguageExt.Prelude;

namespace ErsatzTV.Infrastructure.Emby
{
    public class EmbyApiClient : IEmbyApiClient
    {
        private readonly IFallbackMetadataProvider _fallbackMetadataProvider;
        private readonly ILogger<EmbyApiClient> _logger;

        public EmbyApiClient(IFallbackMetadataProvider fallbackMetadataProvider, ILogger<EmbyApiClient> logger)
        {
            _fallbackMetadataProvider = fallbackMetadataProvider;
            _logger = logger;
        }

        public async Task<Either<BaseError, EmbyServerInformation>> GetServerInformation(
            string address,
            string apiKey)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                var cts = new CancellationTokenSource();
                cts.CancelAfter(TimeSpan.FromSeconds(5));
                return await service.GetSystemInformation(apiKey, cts.Token)
                    .Map(response => new EmbyServerInformation(response.ServerName, response.OperatingSystem));
            }
            catch (OperationCanceledException ex)
            {
                _logger.LogError(ex, "Timeout getting emby server name");
                return BaseError.New("Emby did not respond in time");
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby server name");
                return BaseError.New(ex.Message);
            }
        }

        public async Task<Either<BaseError, List<EmbyLibrary>>> GetLibraries(string address, string apiKey)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                List<EmbyLibraryResponse> libraries = await service.GetLibraries(apiKey);
                return libraries
                    .Map(Project)
                    .Somes()
                    .ToList();
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby libraries");
                return BaseError.New(ex.Message);
            }
        }

        public async Task<Either<BaseError, List<EmbyMovie>>> GetMovieLibraryItems(
            string address,
            string apiKey,
            int mediaSourceId,
            string libraryId)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                EmbyLibraryItemsResponse items = await service.GetMovieLibraryItems(apiKey, libraryId);
                return items.Items
                    .Map(ProjectToMovie)
                    .Somes()
                    .ToList();
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby movie library items");
                return BaseError.New(ex.Message);
            }
        }

        public async Task<Either<BaseError, List<EmbyShow>>> GetShowLibraryItems(
            string address,
            string apiKey,
            int mediaSourceId,
            string libraryId)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                EmbyLibraryItemsResponse items = await service.GetShowLibraryItems(apiKey, libraryId);
                return items.Items
                    .Map(ProjectToShow)
                    .Somes()
                    .ToList();
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby show library items");
                return BaseError.New(ex.Message);
            }
        }

        public async Task<Either<BaseError, List<EmbySeason>>> GetSeasonLibraryItems(
            string address,
            string apiKey,
            int mediaSourceId,
            string showId)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                EmbyLibraryItemsResponse items = await service.GetSeasonLibraryItems(apiKey, showId);
                return items.Items
                    .Map(ProjectToSeason)
                    .Somes()
                    .ToList();
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby show library items");
                return BaseError.New(ex.Message);
            }
        }

        public async Task<Either<BaseError, List<EmbyEpisode>>> GetEpisodeLibraryItems(
            string address,
            string apiKey,
            int mediaSourceId,
            string seasonId)
        {
            try
            {
                IEmbyApi service = RestService.For<IEmbyApi>(address);
                EmbyLibraryItemsResponse items = await service.GetEpisodeLibraryItems(apiKey, seasonId);
                return items.Items
                    .Map(ProjectToEpisode)
                    .Somes()
                    .ToList();
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error getting emby episode library items");
                return BaseError.New(ex.Message);
            }
        }

        private static Option<EmbyLibrary> Project(EmbyLibraryResponse response) =>
            response.CollectionType?.ToLowerInvariant() switch
            {
                "tvshows" => new EmbyLibrary
                {
                    ItemId = response.ItemId,
                    Name = response.Name,
                    MediaKind = LibraryMediaKind.Shows,
                    ShouldSyncItems = false,
                    Paths = new List<LibraryPath> { new() { Path = $"emby://{response.ItemId}" } }
                },
                "movies" => new EmbyLibrary
                {
                    ItemId = response.ItemId,
                    Name = response.Name,
                    MediaKind = LibraryMediaKind.Movies,
                    ShouldSyncItems = false,
                    Paths = new List<LibraryPath> { new() { Path = $"emby://{response.ItemId}" } }
                },
                // TODO: ??? for music libraries
                _ => None
            };

        private Option<EmbyMovie> ProjectToMovie(EmbyLibraryItemResponse item)
        {
            try
            {
                if (item.MediaSources.Any(ms => ms.Protocol != "File"))
                {
                    return None;
                }

                var version = new MediaVersion
                {
                    Name = "Main",
                    Duration = TimeSpan.FromTicks(item.RunTimeTicks),
                    DateAdded = item.DateCreated.UtcDateTime,
                    MediaFiles = new List<MediaFile>
                    {
                        new()
                        {
                            Path = item.Path
                        }
                    },
                    Streams = new List<MediaStream>()
                };

                MovieMetadata metadata = ProjectToMovieMetadata(item);

                var movie = new EmbyMovie
                {
                    ItemId = item.Id,
                    Etag = item.Etag,
                    MediaVersions = new List<MediaVersion> { version },
                    MovieMetadata = new List<MovieMetadata> { metadata }
                };

                return movie;
            }
            catch (Exception ex)
            {
                _logger.LogWarning(ex, "Error projecting Emby movie");
                return None;
            }
        }

        private MovieMetadata ProjectToMovieMetadata(EmbyLibraryItemResponse item)
        {
            DateTime dateAdded = item.DateCreated.UtcDateTime;
            // DateTime lastWriteTime = DateTimeOffset.FromUnixTimeSeconds(item.UpdatedAt).DateTime;

            var metadata = new MovieMetadata
            {
                Title = item.Name,
                SortTitle = _fallbackMetadataProvider.GetSortTitle(item.Name),
                Plot = item.Overview,
                Year = item.ProductionYear,
                Tagline = Optional(item.Taglines).Flatten().HeadOrNone().IfNone(string.Empty),
                DateAdded = dateAdded,
                Genres = Optional(item.Genres).Flatten().Map(g => new Genre { Name = g }).ToList(),
                Tags = Optional(item.Tags).Flatten().Map(t => new Tag { Name = t }).ToList(),
                Studios = Optional(item.Studios).Flatten().Map(s => new Studio { Name = s.Name }).ToList(),
                Actors = Optional(item.People).Flatten().Map(r => ProjectToModel(r, dateAdded)).ToList(),
                Artwork = new List<Artwork>()
            };

            // set order on actors
            for (var i = 0; i < metadata.Actors.Count; i++)
            {
                metadata.Actors[i].Order = i;
            }

            if (DateTime.TryParse(item.PremiereDate, out DateTime releaseDate))
            {
                metadata.ReleaseDate = releaseDate;
            }

            if (!string.IsNullOrWhiteSpace(item.ImageTags.Primary))
            {
                var poster = new Artwork
                {
                    ArtworkKind = ArtworkKind.Poster,
                    Path = $"emby://Items/{item.Id}/Images/Primary?tag={item.ImageTags.Primary}",
                    DateAdded = dateAdded
                };
                metadata.Artwork.Add(poster);
            }

            if (item.BackdropImageTags.Any())
            {
                var fanArt = new Artwork
                {
                    ArtworkKind = ArtworkKind.FanArt,
                    Path = $"emby://Items/{item.Id}/Images/Backdrop?tag={item.BackdropImageTags.Head()}",
                    DateAdded = dateAdded
                };
                metadata.Artwork.Add(fanArt);
            }

            return metadata;
        }

        private Actor ProjectToModel(EmbyPersonResponse person, DateTime dateAdded)
        {
            var actor = new Actor { Name = person.Name, Role = person.Role };
            if (!string.IsNullOrWhiteSpace(person.Id) && !string.IsNullOrWhiteSpace(person.PrimaryImageTag))
            {
                actor.Artwork = new Artwork
                {
                    Path = $"emby://Items/{person.Id}/Images/Primary?tag={person.PrimaryImageTag}",
                    ArtworkKind = ArtworkKind.Thumbnail,
                    DateAdded = dateAdded
                };
            }

            return actor;
        }

        private Option<EmbyShow> ProjectToShow(EmbyLibraryItemResponse item)
        {
            try
            {
                ShowMetadata metadata = ProjectToShowMetadata(item);

                var show = new EmbyShow
                {
                    ItemId = item.Id,
                    Etag = item.Etag,
                    ShowMetadata = new List<ShowMetadata> { metadata }
                };

                return show;
            }
            catch (Exception ex)
            {
                _logger.LogWarning(ex, "Error projecting Emby show");
                return None;
            }
        }

        private ShowMetadata ProjectToShowMetadata(EmbyLibraryItemResponse item)
        {
            DateTime dateAdded = item.DateCreated.UtcDateTime;
            // DateTime lastWriteTime = DateTimeOffset.FromUnixTimeSeconds(item.UpdatedAt).DateTime;

            var metadata = new ShowMetadata
            {
                Title = item.Name,
                SortTitle = _fallbackMetadataProvider.GetSortTitle(item.Name),
                Plot = item.Overview,
                Year = item.ProductionYear,
                Tagline = Optional(item.Taglines).Flatten().HeadOrNone().IfNone(string.Empty),
                DateAdded = dateAdded,
                Genres = Optional(item.Genres).Flatten().Map(g => new Genre { Name = g }).ToList(),
                Tags = Optional(item.Tags).Flatten().Map(t => new Tag { Name = t }).ToList(),
                Studios = Optional(item.Studios).Flatten().Map(s => new Studio { Name = s.Name }).ToList(),
                Actors = Optional(item.People).Flatten().Map(r => ProjectToModel(r, dateAdded)).ToList(),
                Artwork = new List<Artwork>()
            };

            // set order on actors
            for (var i = 0; i < metadata.Actors.Count; i++)
            {
                metadata.Actors[i].Order = i;
            }

            if (DateTime.TryParse(item.PremiereDate, out DateTime releaseDate))
            {
                metadata.ReleaseDate = releaseDate;
            }

            if (!string.IsNullOrWhiteSpace(item.ImageTags.Primary))
            {
                var poster = new Artwork
                {
                    ArtworkKind = ArtworkKind.Poster,
                    Path = $"emby://Items/{item.Id}/Images/Primary?tag={item.ImageTags.Primary}",
                    DateAdded = dateAdded
                };
                metadata.Artwork.Add(poster);
            }

            if (item.BackdropImageTags.Any())
            {
                var fanArt = new Artwork
                {
                    ArtworkKind = ArtworkKind.FanArt,
                    Path = $"emby://Items/{item.Id}/Images/Backdrop?tag={item.BackdropImageTags.Head()}",
                    DateAdded = dateAdded
                };
                metadata.Artwork.Add(fanArt);
            }

            return metadata;
        }

        private Option<EmbySeason> ProjectToSeason(EmbyLibraryItemResponse item)
        {
            try
            {
                DateTime dateAdded = item.DateCreated.UtcDateTime;
                // DateTime lastWriteTime = DateTimeOffset.FromUnixTimeSeconds(response.UpdatedAt).DateTime;

                var metadata = new SeasonMetadata
                {
                    Title = item.Name,
                    SortTitle = _fallbackMetadataProvider.GetSortTitle(item.Name),
                    Year = item.ProductionYear,
                    DateAdded = dateAdded,
                    Artwork = new List<Artwork>()
                };

                if (!string.IsNullOrWhiteSpace(item.ImageTags.Primary))
                {
                    var poster = new Artwork
                    {
                        ArtworkKind = ArtworkKind.Poster,
                        Path = $"emby://Items/{item.Id}/Images/Primary?tag={item.ImageTags.Primary}",
                        DateAdded = dateAdded
                    };
                    metadata.Artwork.Add(poster);
                }

                if (item.BackdropImageTags.Any())
                {
                    var fanArt = new Artwork
                    {
                        ArtworkKind = ArtworkKind.FanArt,
                        Path = $"emby://Items/{item.Id}/Images/Backdrop?tag={item.BackdropImageTags.Head()}",
                        DateAdded = dateAdded
                    };
                    metadata.Artwork.Add(fanArt);
                }

                var season = new EmbySeason
                {
                    ItemId = item.Id,
                    Etag = item.Etag,
                    SeasonMetadata = new List<SeasonMetadata> { metadata }
                };

                if (item.IndexNumber.HasValue)
                {
                    season.SeasonNumber = item.IndexNumber.Value;
                }

                return season;
            }
            catch (Exception ex)
            {
                _logger.LogWarning(ex, "Error projecting Emby show");
                return None;
            }
        }

        private Option<EmbyEpisode> ProjectToEpisode(EmbyLibraryItemResponse item)
        {
            try
            {
                if (item.LocationType == "Virtual")
                {
                    return None;
                }

                var version = new MediaVersion
                {
                    Name = "Main",
                    Duration = TimeSpan.FromTicks(item.RunTimeTicks),
                    DateAdded = item.DateCreated.UtcDateTime,
                    MediaFiles = new List<MediaFile>
                    {
                        new()
                        {
                            Path = item.Path
                        }
                    },
                    Streams = new List<MediaStream>()
                };

                EpisodeMetadata metadata = ProjectToEpisodeMetadata(item);

                var episode = new EmbyEpisode
                {
                    ItemId = item.Id,
                    Etag = item.Etag,
                    MediaVersions = new List<MediaVersion> { version },
                    EpisodeMetadata = new List<EpisodeMetadata> { metadata }
                };

                if (item.IndexNumber.HasValue)
                {
                    episode.EpisodeNumber = item.IndexNumber.Value;
                }

                return episode;
            }
            catch (Exception ex)
            {
                _logger.LogWarning(ex, "Error projecting Emby movie");
                return None;
            }
        }

        private EpisodeMetadata ProjectToEpisodeMetadata(EmbyLibraryItemResponse item)
        {
            DateTime dateAdded = item.DateCreated.UtcDateTime;
            // DateTime lastWriteTime = DateTimeOffset.FromUnixTimeSeconds(item.UpdatedAt).DateTime;

            var metadata = new EpisodeMetadata
            {
                Title = item.Name,
                SortTitle = _fallbackMetadataProvider.GetSortTitle(item.Name),
                Plot = item.Overview,
                Year = item.ProductionYear,
                DateAdded = dateAdded,
                Genres = new List<Genre>(),
                Tags = new List<Tag>(),
                Studios = new List<Studio>(),
                Actors = new List<Actor>(),
                Artwork = new List<Artwork>()
            };

            if (DateTime.TryParse(item.PremiereDate, out DateTime releaseDate))
            {
                metadata.ReleaseDate = releaseDate;
            }

            if (!string.IsNullOrWhiteSpace(item.ImageTags.Primary))
            {
                var thumbnail = new Artwork
                {
                    ArtworkKind = ArtworkKind.Thumbnail,
                    Path = $"emby://Items/{item.Id}/Images/Primary?tag={item.ImageTags.Primary}",
                    DateAdded = dateAdded
                };
                metadata.Artwork.Add(thumbnail);
            }

            return metadata;
        }
    }
}