Add api endpoint to generate the required login cookie

(cherry picked from commit 4180e2787a1ad5284873de4847f345b2c47df72a)

src/Radarr.Api.V4/Authentication/AuthenticationController.cs

@@ -4,8 +4,10 @@ using System.Security.Claims;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Authentication;
 using Microsoft.AspNetCore.Mvc;
+using NzbDrone.Core.Configuration;
 using NzbDrone.Core.Notifications.Plex.PlexTv;
 using Radarr.Http;
+using Radarr.Http.Authentication.Plex;
 
 namespace Radarr.Api.V4.Authentication
 {
@@ -13,10 +15,14 @@ namespace Radarr.Api.V4.Authentication
     public class AuthenticationController : Controller
     {
         private readonly IPlexTvService _plex;
+        private readonly IConfigService _configService;
+        private readonly IConfigFileProvider _configFileProvider;
 
-        public AuthenticationController(IPlexTvService plex)
+        public AuthenticationController(IPlexTvService plex, IConfigService configService, IConfigFileProvider configFileProvider)
         {
             _plex = plex;
+            _configService = configService;
+            _configFileProvider = configFileProvider;
         }
 
         [HttpGet("plex/resources")]
@@ -24,5 +30,32 @@ namespace Radarr.Api.V4.Authentication
         {
             return _plex.GetResources(accessToken);
         }
+
+        [HttpGet("cookie")]
+        public async Task<IActionResult> GetCookie()
+        {
+            var authType = _configFileProvider.AuthenticationMethod;
+
+            var claims = new List<Claim>
+            {
+                new Claim("user", "Anonymous"),
+                new Claim("AuthType", authType.ToString())
+            };
+
+            if (authType == NzbDrone.Core.Authentication.AuthenticationType.Plex)
+            {
+                var claimType = _configService.PlexRequireOwner ? PlexConstants.ServerOwnedClaim : PlexConstants.ServerAccessClaim;
+                claims.Add(new Claim(claimType, _configService.PlexAuthServer));
+            }
+
+            var properties = new AuthenticationProperties
+            {
+                IsPersistent = true
+            };
+
+            await HttpContext.SignInAsync(authType.ToString(), new ClaimsPrincipal(new ClaimsIdentity(claims, "Cookies", "user", "identifier")), properties);
+
+            return StatusCode((int)HttpStatusCode.OK);
+        }
     }
 }