using AsbCloudApp.Data;
using AsbCloudApp.Repositories;
using AsbCloudApp.Requests;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace AsbCloudApp.Services;

/// <summary>
/// Сервис доступа к файлам
/// </summary>
public class FileService
{
    private readonly IFileRepository fileRepository;
    private readonly IFileStorageRepository fileStorageRepository;

    /// <summary>
    /// Сервис доступа к файлам
    /// </summary>
    /// <param name="fileRepository"></param>
    /// <param name="fileStorageRepository"></param>
    public FileService(IFileRepository fileRepository, IFileStorageRepository fileStorageRepository)
    {
        this.fileRepository = fileRepository;
        this.fileStorageRepository = fileStorageRepository;
    }

    /// <summary>
    /// переместить файл
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="idUser"></param>
    /// <param name="idCategory"></param>
    /// <param name="destinationFileName"></param>
    /// <param name="srcFilePath"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<FileInfoDto?> MoveAsync(int idWell, int? idUser, int idCategory,
        string destinationFileName, string srcFilePath, CancellationToken token = default)
    {
        destinationFileName = Path.GetFileName(destinationFileName);
        srcFilePath = Path.GetFullPath(srcFilePath);
        var fileSize = fileStorageRepository.GetFileLength(srcFilePath);

        //save info to db
        var dto = new FileInfoDto {
            IdWell = idWell,
            IdAuthor = idUser,
            IdCategory = idCategory,
            Name = destinationFileName,
            Size = fileSize
        };
        var fileId = await fileRepository.InsertAsync(dto, token)
            .ConfigureAwait(false);
        
        string filePath = fileStorageRepository.MakeFilePath(idWell, idCategory, destinationFileName, fileId);
        fileStorageRepository.MoveFile(srcFilePath, filePath);
        
        return await GetOrDefaultAsync(fileId, token);
    }

    /// <summary>
    /// Сохранить файл
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="idUser"></param>
    /// <param name="idCategory"></param>
    /// <param name="fileFullName"></param>
    /// <param name="fileStream"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<FileInfoDto> SaveAsync(int idWell, int? idUser, int idCategory,
        string fileFullName, Stream fileStream, CancellationToken token)
    {
        //save info to db
        var dto = new FileInfoDto
        {
            IdWell = idWell,
            IdAuthor = idUser,
            IdCategory = idCategory,
            Name = Path.GetFileName(fileFullName),
            Size = fileStream.Length
        };

        var fileId = await fileRepository.InsertAsync(dto, token)
            .ConfigureAwait(false);

        //save stream to disk
        string filePath = fileStorageRepository.MakeFilePath(idWell, idCategory, fileFullName, fileId);
        await fileStorageRepository.SaveFileAsync(filePath, fileStream, token);

        return (await GetOrDefaultAsync(fileId, token))!;
    }

    /// <summary>
    /// удалить файл
    /// </summary>
    /// <param name="idFile"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<int> DeleteAsync(int idFile, CancellationToken token)
        => DeleteAsync(new int[] { idFile }, token);

    /// <summary>
    /// удалить файлы
    /// </summary>
    /// <param name="ids"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<int> DeleteAsync(IEnumerable<int> ids, CancellationToken token)
    {
        if (ids is null || !ids.Any())
            return 0;

        var files = await fileRepository.DeleteAsync(ids, token).ConfigureAwait(false);

        if (files is null || !files.Any())
            return 0;

        var filesName = files.Select(x => GetUrl(x.IdWell, x.IdCategory, x.Id, Path.GetExtension(x.Name)));
        fileStorageRepository.DeleteFiles(filesName);

        return files.Any() ? 1 : 0;
    }

    /// <summary>
    /// получить путь для скачивания
    /// </summary>
    /// <param name="fileInfo"></param>
    /// <returns></returns>
    public string GetUrl(FileInfoDto fileInfo) =>
        GetUrl(fileInfo.IdWell, fileInfo.IdCategory, fileInfo.Id, Path.GetExtension(fileInfo.Name));

    /// <summary>
    /// получить путь для скачивания
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="idCategory"></param>
    /// <param name="idFile"></param>
    /// <param name="dotExtention"></param>
    /// <returns></returns>
    public string GetUrl(int idWell, int idCategory, int idFile, string dotExtention) =>
        fileStorageRepository.GetFilePath(idWell, idCategory, idFile, dotExtention);

    /// <summary>
    /// пометить метку файла как удаленную
    /// </summary>
    /// <param name="idMark"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<int> MarkFileMarkAsDeletedAsync(int idMark,
        CancellationToken token)
    => fileRepository.MarkFileMarkAsDeletedAsync(new int[] { idMark }, token);

    /// <summary>
    /// Инфо о файле
    /// </summary>
    /// <param name="idsFile"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<IEnumerable<FileInfoDto>> GetInfoByIdsAsync(IEnumerable<int> idsFile, CancellationToken token)
    {
        var result = await fileRepository.GetInfoByIdsAsync(idsFile, token).ConfigureAwait(false);
        return result;
    }

    /// <summary>
    /// Получить файлы определенной категории
    /// </summary>
    /// <param name="request"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<IEnumerable<FileInfoDto>> GetInfosAsync(FileRequest request, CancellationToken token)
        => fileRepository.GetInfosAsync(request, token);

    /// <summary>
    /// Получить список файлов в контейнере
    /// </summary>
    /// <param name="request"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<PaginationContainer<FileInfoDto>> GetInfosPaginatedAsync(FileRequest request, CancellationToken token)
        => fileRepository.GetInfosPaginatedAsync(request, token);

    /// <summary>
    /// Пометить файл как удаленный
    /// </summary>
    /// <param name="idFile"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<int> MarkAsDeletedAsync(int idFile, CancellationToken token = default)
        => fileRepository.MarkAsDeletedAsync(idFile, token);

    /// <summary>
    /// добавить метку на файл
    /// </summary>
    /// <param name="fileMarkDto"></param>
    /// <param name="idUser"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<int> CreateFileMarkAsync(FileMarkDto fileMarkDto, int idUser, CancellationToken token)
        => fileRepository.CreateFileMarkAsync(fileMarkDto, idUser, token);

    /// <summary>
    /// Получить запись по id
    /// </summary>
    /// <param name="id"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<FileInfoDto?> GetOrDefaultAsync(int id, CancellationToken token)
        => fileRepository.GetOrDefaultAsync(id, token);

    /// <summary>
    /// получить инфо о файле по метке
    /// </summary>
    /// <param name="idMark"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<FileInfoDto> GetByMarkId(int idMark, CancellationToken token)
        => fileRepository.GetByMarkId(idMark, token);

    /// <summary>
    /// получить инфо о файле по метке
    /// </summary>
    /// <param name="idsMarks"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public Task<int> MarkFileMarkAsDeletedAsync(IEnumerable<int> idsMarks, CancellationToken token)
        => fileRepository.MarkFileMarkAsDeletedAsync(idsMarks, token);

    /// <summary>
    /// Удаление всех файлов по скважине помеченных как удаленные
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<int> DeleteFilesFromDbMarkedDeletionByIdWell(int idWell, CancellationToken token)
    {
        var files = await fileRepository.GetInfosAsync(
            new FileRequest
            {
                IdWell = idWell,
                IsDeleted = true
            },
            token);
        var result = await DeleteAsync(files.Select(x => x.Id), token);
        return result;
    }

    /// <summary>
    /// Удаление всех файлов с диска о которых нет информации в базе
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="token"></param>
    public async Task<int> DeleteFilesNotExistStorage(int idWell, CancellationToken token)
    {
        var files = await fileRepository.GetInfosAsync(
            new FileRequest
            {
                IdWell = idWell
            },
            token);
        var result = await Task.FromResult(fileStorageRepository.DeleteFilesNotInList(idWell, files.Select(x => x.Id)));
        return result;
    }

    /// <summary>
    /// Вывод списка всех файлов из базы, для которых нет файла на диске
    /// </summary>
    /// <param name="idWell"></param>
    /// <param name="token"></param>
    /// <returns></returns>
    public async Task<IEnumerable<FileInfoDto>> GetListFilesNotDisc(int idWell, CancellationToken token)
    {
        var files = await fileRepository.GetInfosAsync(
            new FileRequest
            {
                IdWell = idWell
            },
            token);
        var result = fileStorageRepository.GetListFilesNotDisc(files);
        return result;
    }

    /// <summary>
    /// Получить файловый поток по идентификатору файла
    /// </summary>
    /// <param name="fileInfo"></param>
    /// <returns></returns>
    public Stream GetFileStream(FileInfoDto fileInfo)
    {
        var relativePath = GetUrl(fileInfo);
        var fileStream = new FileStream(Path.GetFullPath(relativePath), FileMode.Open);

        return fileStream;
    }
}