gehgassi_backend/gehGassi.Web/Controllers/WebsiteApi/WebSiteApiBaseController.cs

using AutoMapper;
using gehGassi.Core.Interfaces;
using gehGassi.Web.Helper;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using System.IO;
using System.Threading.Tasks;
using System;
using SixLabors.ImageSharp;
using SixLabors.ImageSharp.Advanced;
using SixLabors.ImageSharp.Processing;

namespace gehGassi.Web.Controllers.WebsiteApi
{
    /// <summary>
    /// Basis-Controller für die Website-API
    /// </summary>
    public class WebSiteApiBaseController : Controller
    {
        public IMapper Mapper { get; }
        public IOptions<LocalizationOptions> LocalizationOptions { get; }
        public IUserService UserService { get; }

        private IFileService _fileService;
        protected IFileService FileService => _fileService ??= HttpContext?.RequestServices.GetService<IFileService>();

        /// <summary>
        /// Erstellt eine Instanz
        /// </summary>
        /// <param name="mapper">Instanz eines IMapper</param>
        /// <param name="localizationOptions">Instanz von LocalizationOptions</param>
        /// <param name="userService">Instanz eines IUserService</param>
        public WebSiteApiBaseController(IMapper mapper, IOptions<LocalizationOptions> localizationOptions, IUserService userService)
        {
            Mapper = mapper;
            LocalizationOptions = localizationOptions;
            UserService = userService;
        }

        /// <summary>
        /// Gibt die Basis-Adresse für URLS zurück
        /// </summary>
        /// <returns></returns>
        internal string GetBaseAddress()
        {
            var baseAddress = $"{HttpContext.Request.Scheme}://{HttpContext.Request.Host}";
#if DEBUG
            baseAddress = "http://10.0.0.31:54763";
#endif
            return baseAddress;
        }

        /// <summary>
        /// Erstellt ein Thumbnail basierend auf der Breite
        /// </summary>
        /// <param name="container">Container</param>
        /// <param name="filename">Dateiname</param>
        /// <param name="size">Größe für Breite und Höhe</param>
        /// <returns>Task</returns>
        internal async Task GenerateThumbnailByWidth(string container, string filename, int size)
        {
            try
            {
                using (var imgStream = await FileService.GetAsStreamAsync(container, filename))
                {
                    using (var img = await Image.LoadAsync(imgStream))
                    {
                        img.Mutate(x => x.Resize(new ResizeOptions() { Mode = ResizeMode.Max, Size = new Size(size) }));

                        var format = img.DetectEncoder(filename);

                        await using (var memStream = new MemoryStream())
                        {
                            await img.SaveAsync(memStream, format);
                            memStream.Position = 0;
                            await FileService.StoreAsync(container, $"thumbnails/{size}/{filename}", memStream);
                        }
                    }
                }
            }
            catch
            {

            }
        }

        /// <summary>
        /// Löschen eines Thumbnails für ein Bild
        /// </summary>
        /// <param name="container">Container</param>
        /// <param name="fileName">Dateiname</param>
        /// <param name="size">Größe für Breite und Höhe</param>
        /// <returns>Task</returns>
        internal async Task RemoveThumbnail(string container, string fileName, int size)
        {
            try
            {
                var file = await FileService.GetAsync(container, $"thumbnails/{size}/{fileName}");
                if (file != null)
                {
                    await FileService.DeleteAsync(container, $"thumbnails/{size}/{fileName}");
                }
            }
            catch
            {

            }
        }

        /// <summary>
        /// Gibt den Offset zwischen der Server- und der Client-Zeit zurück
        /// </summary>
        /// <returns></returns>
        protected int GetClientDateOffset()
        {
            var compareDate = DateTimeOffset.UtcNow;
            var dateOffset = 0;

            try
            {
                if (Request.Headers.ContainsKey("clientTime"))
                {
                    var requestHeader = Request.Headers["clientTime"];

                    DateTimeOffset clientDate;
                    if (DateTimeOffset.TryParse(requestHeader, null, System.Globalization.DateTimeStyles.RoundtripKind, out clientDate))
                    {
                        //var clientDate = DateTimeOffset.Parse(Request.Headers["clientTime"], null, System.Globalization.DateTimeStyles.RoundtripKind);
                        dateOffset = (int)(compareDate - clientDate).TotalSeconds;
                    }
                    else
                    {
                        System.Diagnostics.Debug.WriteLine($"ClientOffset header Problem: {Request.Headers["clientTime"]}");
                    }
                }

                //System.Diagnostics.Debug.WriteLine($"ClientOffset in seconds: {dateOffset}");
            }
            catch { }

            return dateOffset;
        }
    }
}