using FileShare_Common.Core;
using FileShare_Services.Core;

namespace FileShare_Services.Services.FileLibrary
{
    /// <summary>
    /// 文件库 HTTP 端点服务，将请求适配到 <see cref="IFileLibraryService"/> 并包装为 <see cref="IApiResponse"/>。
    /// </summary>
    public sealed class FileLibraryEndpointService(IFileLibraryService fileLibrary) : IFileLibraryEndpointService
    {
        /// <inheritdoc />
        public async Task<IApiResponse> GetDrivesAsync(ServiceEndpointContext ctx)
        {
            return ResponseHelper.Ok(await fileLibrary.GetDrivesAsync());
        }

        /// <inheritdoc />
        public async Task<IApiResponse> GetDirectoriesAsync(DirectoryQueryRequest request)
        {
            return ResponseHelper.Ok(await fileLibrary.GetDirectoriesAsync(request.Path));
        }

        /// <inheritdoc />
        public async Task<IApiResponse> GetRootsAsync(ServiceEndpointContext ctx)
        {
            return ResponseHelper.Ok(await fileLibrary.GetRootsAsync());
        }

        /// <inheritdoc />
        public async Task<IApiResponse> AddRootAsync(AddLibraryRootRequest request)
        {
            return ResponseHelper.Ok(await fileLibrary.AddRootAsync(request), "文件库目录已添加，后续扫描将自动入库。");
        }

        /// <inheritdoc />
        public async Task<IApiResponse> SetRootEnabledAsync(UpdateLibraryRootRequest request)
        {
            return ResponseHelper.Ok(await fileLibrary.SetRootEnabledAsync(request), "文件库目录状态已更新。");
        }

        /// <inheritdoc />
        public async Task<IApiResponse> DeleteRootAsync(DeleteLibraryRootRequest request)
        {
            await fileLibrary.DeleteRootAsync(request);
            return ResponseHelper.Succeed("文件库目录已删除。");
        }

        /// <inheritdoc />
        public async Task<IApiResponse> ScanRootAsync(ScanLibraryRootRequest request)
        {
            return ResponseHelper.Ok(await fileLibrary.ScanRootAsync(request.Id), "文件库目录扫描完成。");
        }

        /// <inheritdoc />
        public async Task<IApiResponse> SearchFilesAsync(SearchFilesRequest request)
        {
            return await fileLibrary.SearchFilesAsync(request);
        }

        /// <inheritdoc />
        public async Task<IApiResponse> GetFileAsync(FileQueryRequest request)
        {
            ValidateFileId(request.Id);
            var file = await fileLibrary.GetFileAsync(request.Id);
            return file is null
                ? ResponseHelper.Failure(404, "文件不存在或尚未扫描入库。")
                : ResponseHelper.Ok(file);
        }

        /// <inheritdoc />
        public async Task<IApiResponse> GetTextPreviewAsync(FileQueryRequest request)
        {
            ValidateFileId(request.Id);
            var preview = await fileLibrary.GetTextPreviewAsync(request.Id);
            return preview is null
                ? ResponseHelper.Failure(404, "文本文件不存在或无法预览。")
                : ResponseHelper.Ok(preview);
        }

        /// <inheritdoc />
        public async Task<IApiResponse> BrowseDirectoryAsync(BrowseDirectoryRequest request)
        {
            if (request.RootId <= 0)
                return ResponseHelper.Failure(400, "rootId 参数无效。");

            var result = await fileLibrary.BrowseDirectoryAsync(request);
            return ResponseHelper.Ok(result);
        }

        /// <inheritdoc />
        public async Task<IApiResponse> GetRecentFilesAsync(RecentFilesRequest request)
        {
            var items = await fileLibrary.GetRecentFilesAsync(request.Type, request.Count);
            return ResponseHelper.Ok(items);
        }

        /// <inheritdoc />
        public async Task<IApiResponse> MarkFilePlayedAsync(MarkFilePlayedRequest request)
        {
            await fileLibrary.MarkFilePlayedAsync(request.Id);
            return ResponseHelper.Succeed();
        }

        /// <summary>
        /// 验证文件 ID 是否有效，无效时抛出 <see cref="ArgumentException"/>。
        /// </summary>
        /// <param name="id">文件记录 ID。</param>
        /// <exception cref="ArgumentException">ID 小于等于 0 时抛出。</exception>
        private static void ValidateFileId(int id)
        {
            if (id > 0)
            {
                return;
            }

            throw new ArgumentException("id 参数无效。");
        }
    }
}