using System.Text.RegularExpressions;
using dy.net.model.dto;
using dy.net.model.entity;
using dy.net.model.response;
using dy.net.utils;

namespace dy.net.storage
{
    public sealed class StorageMigrationPathPlan
    {
        public string VideoPath { get; set; }
        public string CoverPath { get; set; }
        public string AvatarPath { get; set; }
        public string DirectoryPath => StoragePath.DirectoryName(VideoPath);
    }

    public static class StorageMigrationPathPolicy
    {
        private static readonly Regex EpisodeName = new("^S(?<season>\\d{2})E(?<episode>\\d{2,})$", RegexOptions.IgnoreCase | RegexOptions.Compiled);

        public static StorageMigrationPathPlan Build(
            DouyinVideo video,
            DouyinCookie cookie,
            DouyinCollectCate category,
            DouyinFollowed followed,
            AppConfig config,
            int episodeNumber = 1)
        {
            if (video == null) throw new ArgumentNullException(nameof(video));
            if (cookie == null) throw new InvalidOperationException($"视频 {video.AwemeId} 缺少所属账号");

            var root = GetRemoteRoot(cookie, video.ViedoType);
            if (string.IsNullOrWhiteSpace(root)) throw new InvalidOperationException($"账号 {cookie.UserName} 未配置 {video.ViedoType} 的远端目标路径");

            var extension = NormalizeExtension(Path.GetExtension(video.VideoSavePath));
            var awemeId = string.IsNullOrWhiteSpace(video.AwemeId) ? video.Id : video.AwemeId;
            var titleFolder = DouyinFileNameHelper.SanitizeLinuxFileName(video.VideoTitle, awemeId, true);
            var authorFolder = DouyinFileNameHelper.SanitizeLinuxFileName(video.Author, video.AuthorId ?? "未知博主", true);
            string directory;
            string fileName;

            switch (video.ViedoType)
            {
                case VideoTypeEnum.dy_custom_collect:
                    var customCategory = DouyinFileNameHelper.SanitizeLinuxFileName(category?.SaveFolder, category?.Name ?? "未分类", true);
                    directory = StoragePath.CombineRemote(root, customCategory, titleFolder + "_" + awemeId);
                    fileName = awemeId + extension;
                    break;
                case VideoTypeEnum.dy_mix:
                case VideoTypeEnum.dy_series:
                    var seriesFolder = DouyinFileNameHelper.SanitizeLinuxFileName(category?.SaveFolder, category?.Name ?? video.CateXId ?? "未分类", true);
                    directory = StoragePath.CombineRemote(root, seriesFolder);
                    var oldEpisode = EpisodeName.Match(Path.GetFileNameWithoutExtension(video.VideoSavePath) ?? string.Empty);
                    fileName = oldEpisode.Success
                        ? oldEpisode.Value.ToUpperInvariant() + extension
                        : $"S01E{Math.Max(1, episodeNumber):D2}{extension}";
                    break;
                case VideoTypeEnum.dy_follows:
                    var followedFolder = string.IsNullOrWhiteSpace(followed?.SavePath) ? authorFolder : followed.SavePath;
                    directory = StoragePath.CombineRemote(root, followedFolder, titleFolder);
                    fileName = BuildFollowedFileName(video, config, extension, awemeId);
                    break;
                case VideoTypeEnum.dy_favorite:
                case VideoTypeEnum.dy_collects:
                default:
                    directory = StoragePath.CombineRemote(root, authorFolder, titleFolder + "_" + awemeId);
                    fileName = awemeId + extension;
                    break;
            }

            var videoPath = StoragePath.CombineRemote(directory, fileName);
            var coverName = video.ViedoType is VideoTypeEnum.dy_mix or VideoTypeEnum.dy_series
                ? "poster.jpg"
                : Path.GetFileNameWithoutExtension(fileName) + "-poster.jpg";
            return new StorageMigrationPathPlan
            {
                VideoPath = videoPath,
                CoverPath = StoragePath.CombineRemote(directory, coverName),
                AvatarPath = string.IsNullOrWhiteSpace(video.AuthorAvatar) && string.IsNullOrWhiteSpace(video.AuthorAvatarUrl)
                    ? string.Empty
                    : StoragePath.CombineRemote(root, "author", (string.IsNullOrWhiteSpace(video.AuthorId) ? awemeId : video.AuthorId) + ".jpg")
            };
        }

        public static StorageMigrationPathPlan Build(
            Aweme item,
            VideoTypeEnum type,
            DouyinCookie cookie,
            DouyinCollectCate category,
            DouyinFollowed followed,
            AppConfig config)
        {
            if (item == null) throw new ArgumentNullException(nameof(item));
            var bitrate = item.Video?.BitRate?.FirstOrDefault();
            var format = string.IsNullOrWhiteSpace(bitrate?.Format) ? "mp4" : bitrate.Format.TrimStart('.');
            var createdAt = DateTimeUtil.Convert10BitTimestamp(item.CreateTime);
            var title = string.IsNullOrWhiteSpace(item.Desc)
                ? $"{item.Author?.Nickname}-{item.CreateTime}"
                : item.Desc;
            var video = new DouyinVideo
            {
                ViedoType = type,
                AwemeId = item.AwemeId,
                VideoTitle = title,
                VideoSavePath = $"{item.AwemeId}.{format}",
                Author = item.Author?.Nickname,
                AuthorId = item.Author?.Uid,
                AuthorAvatarUrl = item.Author?.AvatarLarger?.UrlList?.FirstOrDefault()
                                  ?? item.Author?.AvatarThumb?.UrlList?.FirstOrDefault(),
                CreateTime = createdAt,
                FileHash = bitrate?.PlayAddr?.FileHash,
                Resolution = bitrate?.PlayAddr == null ? string.Empty : $"{bitrate.PlayAddr.Width}×{bitrate.PlayAddr.Height}"
            };
            var episode = item.MixInfo?.Statis?.CurrentEpisode ?? 1;
            return Build(video, cookie, category, followed, config, Math.Max(1, episode));
        }

        public static string GetRemoteRoot(DouyinCookie cookie, VideoTypeEnum type) => type switch
        {
            VideoTypeEnum.dy_favorite => cookie.WebDavFavoritePath,
            VideoTypeEnum.dy_follows => cookie.WebDavFollowPath,
            VideoTypeEnum.dy_mix => cookie.WebDavMixPath,
            VideoTypeEnum.dy_series => cookie.WebDavSeriesPath,
            _ => cookie.WebDavCollectPath
        };

        public static IReadOnlyList<string> GetLocalRoots(DouyinCookie cookie)
        {
            if (cookie == null) return Array.Empty<string>();
            return new[] { cookie.SavePath, cookie.FavSavePath, cookie.UpSavePath, cookie.MixPath, cookie.SeriesPath }
                .Where(x => !string.IsNullOrWhiteSpace(x))
                .Select(Path.GetFullPath)
                .Distinct(StringComparer.Ordinal)
                .ToArray();
        }

        private static string BuildFollowedFileName(DouyinVideo video, AppConfig config, string extension, string awemeId)
        {
            if (string.IsNullOrWhiteSpace(config?.FullFollowedTitleTemplate)) return awemeId + extension;
            var generated = VideoTitleGenerator.Generate(config.FullFollowedTitleTemplate, new VideoTitleDataTemplate
            {
                Id = awemeId,
                ReleaseTime = video.CreateTime,
                VideoTitle = video.VideoTitle,
                Author = video.Author,
                FileHash = video.FileHash,
                Resolution = video.Resolution
            });
            generated = DouyinFileNameHelper.SanitizeLinuxFileName(generated, awemeId);
            return generated + extension;
        }

        private static string NormalizeExtension(string extension) => string.IsNullOrWhiteSpace(extension) ? ".mp4" : extension.ToLowerInvariant();
    }
}