using AsbCloudApp.Data;
using AsbCloudApp.Exceptions;
using AsbCloudApp.Services;
using AsbCloudDb.Model;
using AsbCloudInfrastructure.Repository;
using Mapster;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace AsbCloudInfrastructure.Services
{
    public class FileService : IFileService
    {
        public string RootPath { get; private set; }
        private readonly IFileRepository fileRepository;

        public FileService(IFileRepository fileRepository)
        {
            RootPath = "files";
            this.fileRepository = fileRepository;
        }

        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);
            if (!File.Exists(srcFilePath))
                throw new ArgumentInvalidException($"file {srcFilePath} doesn't exist", nameof(srcFilePath));

            var sysFileInfo = new System.IO.FileInfo(srcFilePath);

            //save info to db
            var fileId = await fileRepository.AddAsync(idWell, idUser, idCategory, destinationFileName, sysFileInfo.Length, token)
                .ConfigureAwait(false);
            
            string filePath = MakeFilePath(idWell, idCategory, destinationFileName, fileId);
            Directory.CreateDirectory(Path.GetDirectoryName(filePath));
            File.Move(srcFilePath, filePath);

            return await GetInfoAsync(fileId, token);
        }

        public async Task<FileInfoDto> SaveAsync(int idWell, int? idUser, int idCategory,
            string fileFullName, Stream fileStream, CancellationToken token)
        {
            //save info to db
            var fileId = await fileRepository.AddAsync(idWell, idUser, idCategory, Path.GetFileName(fileFullName), fileStream?.Length ?? 0, token)
                .ConfigureAwait(false);

            //save stream to disk
            string filePath = MakeFilePath(idWell, idCategory, fileFullName, fileId);

            Directory.CreateDirectory(Path.GetDirectoryName(filePath));

            using var newfileStream = new FileStream(filePath, FileMode.Create);
            await fileStream.CopyToAsync(newfileStream, token).ConfigureAwait(false);

            return await GetInfoAsync(fileId, token);
        }

        private string MakeFilePath(int idWell, int idCategory, string fileFullName, int fileId)
        {
            return Path.Combine(RootPath, $"{idWell}",
                    $"{idCategory}", $"{fileId}" + $"{Path.GetExtension(fileFullName)}");
        }

        public async Task<FileInfoDto> GetInfoAsync(int idFile,
            CancellationToken token)
        {
            var dto = await fileRepository.GetInfoAsync(idFile, token).ConfigureAwait(false);

            var ext = Path.GetExtension(dto.Name);

            var relativePath = GetUrl(dto.IdWell, dto.IdCategory, dto.Id, ext);
            var fullPath = Path.GetFullPath(relativePath);
            if (!File.Exists(fullPath))
            {
                throw new FileNotFoundException("not found", relativePath);
            }

            return dto;
        }

        public Task<int> DeleteAsync(int idFile, CancellationToken token)
        => DeleteAsync(new int[] { idFile }, token);

        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;

            foreach (var file in files)
            {
                var fileName = GetUrl(file.IdWell, file.IdCategory, file.Id, Path.GetExtension(file.Name));
                if (File.Exists(fileName))
                    File.Delete(fileName);
            }

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

        public async Task<string> GetUrl(int idFile)
        {
            var fileInfo = await fileRepository.GetInfoAsync(idFile, CancellationToken.None).ConfigureAwait(false);

            return GetUrl(fileInfo.IdWell, fileInfo.IdCategory, fileInfo.Id, Path.GetExtension(fileInfo.Name));
        }

        public string GetUrl(FileInfoDto fileInfo) =>
            GetUrl(fileInfo.IdWell, fileInfo.IdCategory, fileInfo.Id, Path.GetExtension(fileInfo.Name));

        public string GetUrl(int idWell, int idCategory, int idFile, string dotExtention) =>
            Path.Combine(RootPath, idWell.ToString(), idCategory.ToString(), $"{idFile}{dotExtention}");

        public Task<int> MarkFileMarkAsDeletedAsync(int idMark,
            CancellationToken token)
        => fileRepository.MarkFileMarkAsDeletedAsync(new int[] { idMark }, token);

        public async Task<IEnumerable<FileInfoDto>> GetInfoByIdsAsync(IEnumerable<int> idsFile, CancellationToken token)
        {
            var result = await fileRepository.GetInfoByIdsAsync(idsFile, token).ConfigureAwait(false);

            foreach (var entity in result)
            {
                
                var ext = Path.GetExtension(entity.Name);
                var relativePath = GetUrl(entity.IdWell, entity.IdCategory, entity.Id, ext);
                var fullPath = Path.GetFullPath(relativePath);
                if (!File.Exists(fullPath))
                {
                    throw new FileNotFoundException("not found", relativePath);
                }
            }
            
            return result;
        }
    }
}