laatzen/LaaProductionWeb/LaaProduction.Web/App_Infrastructure/HttpExtensions.cs

namespace LaaProduction.Web.App_Infrastructure
{
    using LaaProductionHttp.Interfaces;

    using Newtonsoft.Json;

    using System;
    using System.Linq;
    using System.Net;
    using System.Security.Claims;
    using System.Security.Cryptography;
    using System.Security.Principal;
    using System.Text;
    using System.Web;
    using System.Web.Mvc;

    /// <summary>
    /// Static class with extension methods that run on controller contexts.
    /// </summary>
    public static class HttpExtensions
    {
        const string ORDER_DATA = nameof(ORDER_DATA);
        const string URL_REFERER = nameof(URL_REFERER);
        const string LAA_USER = nameof(LAA_USER);

        public static TDST Map<TSRC, TDST>(this TSRC model, Func<TSRC, TDST> mapper)
            where TDST : class
            where TSRC : class
        {
            if (model is null)
            {
                return default(TDST);
            }

            return mapper(model);
        }

        public static bool IsInRole<T>(this IPrincipal principal, T role)
            => principal.IsInRole($"{role}");

        public static string GetNameIdentifier(this IPrincipal principal)
        {
            if (principal is ClaimsPrincipal claimsPrincipal)
            {
                return claimsPrincipal
                    .FindFirst(ClaimTypes.NameIdentifier)
                    ?.Value;
            }

            return default(string);
        }

        public static string FullName(this IPrincipal principal)
        {
            if (principal is ClaimsPrincipal claimsPrincipal)
            {
                return claimsPrincipal
                    .FindAll(nameof(FullName))
                    .LastOrDefault()?.Value;
            }

            return "<unknown>";
        }

        public static string ClaimId(this IPrincipal principal)
        {
            if (principal is ClaimsPrincipal claimsPrincipal)
            {
                return claimsPrincipal
                    .FindAll(ClaimTypes.NameIdentifier)
                    .LastOrDefault()?.Value;
            }

            return "<unknown>";
        }

        public static string GetUrlReferer(this HttpContextBase httpContext)
            => httpContext
                .Request
                .Cookies
                .Get(URL_REFERER)
                ?.Value ?? "~/";

        public static void SetUrlReferer(this HttpContextBase httpContext)
            => httpContext
                .Response
                .Cookies
                .Add(new HttpCookie(URL_REFERER, $"{httpContext.Request.Url}"));

        public static void SetUserData(this HttpContextBase httpContext, object data)
        {
            if (data != null)
            {
                var userId = httpContext.User.ClaimId();
                var json = JsonConvert.SerializeObject(data);
                var encoded = WebUtility.UrlEncode(json);
                var cookie = new HttpCookie($"{ORDER_DATA}_{userId}")
                {
                    Value = encoded,
                    Expires = DateTime.Now.AddHours(7)
                };

                httpContext.Response.Cookies.Set(cookie);
            }
        }

        public static T GetUserData<T>(this HttpContextBase httpContext)
        {
            var userId = httpContext.User.ClaimId();
            var cookie = httpContext.Request.Cookies.Get($"{ORDER_DATA}_{userId}");

            if (cookie != null && cookie.Value != null)
            {
                try
                {
                    var json = WebUtility.UrlDecode(cookie.Value);

                    return JsonConvert.DeserializeObject<T>(json);
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.Message);
                }
            }

            return default(T);
        }

        public static string GetSessionUser(this HttpContextBase httpContext)
        {
            var sessionUser = httpContext.Request.Cookies.Get(LAA_USER);

            if (sessionUser is null)
            {
                return default(string);
            }

            sessionUser.Expires = DateTime.UtcNow.AddMinutes(Appsettings.LoginTimeout);

            httpContext.Response.Cookies.Set(sessionUser);

            return sessionUser.Value;
        }

        public static void SignIn(this HttpContextBase httpContext, string token)
        {
            httpContext.Response.Cookies.Add(new HttpCookie(LAA_USER, token)
            {
                Expires = DateTime.UtcNow.AddMinutes(Appsettings.LoginTimeout)
            });
        }

        public static void SignOut(this HttpContextBase httpContext)
        {
            var sessionUser = httpContext.Request.Cookies.Get(LAA_USER);

            if (sessionUser != null)
            {
                sessionUser.Expires = DateTime.UtcNow.AddMinutes(Appsettings.LoginTimeout * -1);

                httpContext.Response.Cookies.Set(sessionUser);
            }
        }

        public static string ComputeHash(this string value)
        {
            if (!string.IsNullOrWhiteSpace(value))
            {
                var bytes = Encoding.UTF8.GetBytes(value);
                var hash = SHA256.Create().ComputeHash(bytes);
                var base64 = Convert.ToBase64String(hash);

                return base64;
            }

            return value;
        }

        public static void AddModelErrors(this ModelStateDictionary modelState, IHttpErrorResponse response)
        {
            if (response != null)
            {
                if (response.Errors != null)
                {
                    foreach (var error in response.Errors)
                    {
                        modelState.AddModelError(error.Key, error.Value);
                    }
                }

                if (!string.IsNullOrWhiteSpace(response.Message))
                {
                    modelState.AddModelError(nameof(response.Message), response.Message);
                }
            }
        }

        public static short GetAppId(this IPrincipal principal)
        {
            if (principal is ClaimsPrincipal claimsPrincipal)
            {
                if (short.TryParse($"{claimsPrincipal.FindFirst("AppId")?.Value}", out short appId))
                {
                    return appId;
                }
            }

            return default(short);
        }
    }
}