using dy.net.model.dto;
using dy.net.model.entity;
using Newtonsoft.Json;
using SqlSugar;
using MediaStorageType = dy.net.model.dto.StorageType;

namespace dy.net.service
{
    public class VideoExclusionService
    {
        private readonly ISqlSugarClient _db;
        private readonly VideoTaskService _tasks;

        public VideoExclusionService(ISqlSugarClient db, VideoTaskService tasks)
        {
            _db = db;
            _tasks = tasks;
        }

        public async Task<VideoExclusionPage> GetPageAsync(VideoExclusionPageRequest request)
        {
            request ??= new VideoExclusionPageRequest();
            var page = Math.Max(1, request.PageIndex);
            var size = Math.Clamp(request.PageSize, 1, 100);
            var query = _db.Queryable<DouyinVideoDelete>()
                .WhereIF(!string.IsNullOrWhiteSpace(request.Keyword), x => x.VideoTitle.Contains(request.Keyword)
                    || x.ViedoId.Contains(request.Keyword) || x.Author.Contains(request.Keyword));
            return new VideoExclusionPage
            {
                TotalCount = await query.CountAsync(),
                Items = await query.OrderByDescending(x => x.DeleteTime).Skip((page - 1) * size).Take(size).ToListAsync()
            };
        }

        public async Task<UnexcludeVideosResult> UnexcludeAsync(UnexcludeVideosRequest request)
        {
            if (request?.Ids == null || request.Ids.Count == 0) throw new InvalidOperationException("请选择要取消排除的视频。");
            var exclusions = await _db.Queryable<DouyinVideoDelete>().Where(x => request.Ids.Contains(x.Id)).ToListAsync();
            if (exclusions.Count == 0) throw new KeyNotFoundException("未找到永久排除记录。");
            var awemeIds = exclusions.Select(x => x.ViedoId).Where(x => !string.IsNullOrWhiteSpace(x)).Distinct().ToList();
            var allDuplicates = awemeIds.Count == 0
                ? exclusions
                : await _db.Queryable<DouyinVideoDelete>().Where(x => awemeIds.Contains(x.ViedoId)).ToListAsync();
            var snapshots = request.CreateDownloadTask
                ? allDuplicates.Select(TryGetSnapshot).Where(x => x != null).GroupBy(x => x.AwemeId).Select(x => x.First()).ToList()
                : new List<DouyinVideo>();
            VideoDownloadTask task = null;
            var result = new UnexcludeVideosResult();
            var transaction = await _db.Ado.UseTranAsync(async () =>
            {
                if (request.CreateDownloadTask && snapshots.Count > 0)
                {
                    task = await _tasks.CreateTaskAsync(VideoTaskType.ExclusionRestore, VideoTaskTrigger.UserAction,
                        $"取消排除恢复（{snapshots.Count} 条）", storageType: snapshots[0].StorageType);
                    foreach (var video in snapshots)
                    {
                        var exclusion = allDuplicates.First(x => x.ViedoId == video.AwemeId);
                        await _tasks.AddItemAsync(task.Id, video.AwemeId, video.CookieId, null, video.ViedoType,
                            video.VideoTitle, video.Author, video.VideoSavePath,
                            new[] { video.VideoUrl }, video, video.FileSize, workerManaged: true);
                    }
                }
                await _db.Deleteable<DouyinVideoDelete>()
                    .Where(x => request.Ids.Contains(x.Id) || awemeIds.Contains(x.ViedoId)).ExecuteCommandAsync();
                var now = DateTime.Now;
                if (awemeIds.Count > 0)
                {
                    var relatedTaskId = task?.Id;
                    await _db.Updateable<VideoDownloadTaskItem>()
                        .SetColumns(x => new VideoDownloadTaskItem
                        {
                            ExclusionReleasedAt = now,
                            RelatedTaskId = relatedTaskId,
                            UpdatedAt = now
                        }).Where(x => awemeIds.Contains(x.AwemeId) && x.SkipReason == VideoTaskSkipReason.PermanentlyExcluded)
                        .ExecuteCommandAsync();
                }
            });
            if (!transaction.IsSuccess) throw new InvalidOperationException("取消排除失败：" + transaction.ErrorMessage);

            result.ReleasedCount = awemeIds.Count;
            result.QueuedCount = snapshots.Count;
            result.TaskId = task?.Id;
            result.CannotQueueIds = request.CreateDownloadTask
                ? awemeIds.Where(id => snapshots.All(x => x.AwemeId != id)).ToList()
                : new List<string>();
            result.Message = result.CannotQueueIds.Count > 0
                ? $"已取消排除 {result.ReleasedCount} 条，其中 {result.CannotQueueIds.Count} 条旧记录资料不足，将在下次正常同步时重新发现。"
                : task == null
                    ? $"已取消排除 {result.ReleasedCount} 条，将在下次正常同步时重新发现。"
                    : $"已取消排除并创建 {result.QueuedCount} 条恢复下载任务。";
            return result;
        }

        private static DouyinVideo TryGetSnapshot(DouyinVideoDelete exclusion)
        {
            if (!string.IsNullOrWhiteSpace(exclusion.RestoreSnapshotJson))
            {
                try
                {
                    var snapshot = JsonConvert.DeserializeObject<DouyinVideo>(exclusion.RestoreSnapshotJson);
                    if (snapshot != null && !string.IsNullOrWhiteSpace(snapshot.AwemeId) && !string.IsNullOrWhiteSpace(snapshot.CookieId)) return snapshot;
                }
                catch { }
            }
            if (string.IsNullOrWhiteSpace(exclusion.ViedoId) || string.IsNullOrWhiteSpace(exclusion.CookieId)
                || !exclusion.VideoType.HasValue || string.IsNullOrWhiteSpace(exclusion.VideoUrl)) return null;
            return new DouyinVideo
            {
                Id = Guid.NewGuid().ToString("N"),
                AwemeId = exclusion.ViedoId,
                CookieId = exclusion.CookieId,
                ViedoType = exclusion.VideoType.Value,
                VideoTitle = exclusion.VideoTitle,
                VideoSavePath = exclusion.VideoSavePath,
                VideoUrl = exclusion.VideoUrl,
                AuthorId = exclusion.AuthorId,
                Author = exclusion.Author,
                StorageType = MediaStorageType.Local,
                SyncTime = DateTime.Now
            };
        }
    }
}