User: split the username into localpart and domain (if given)

library/Icinga/Authentication/User/UserBackend.php

@@ -231,4 +231,55 @@ class UserBackend implements ConfigAwareFactory
         $backend->setName($name);
         return $backend;
     }
+
+    /**
+     * Return whether the given backend is responsible for authenticating the given user (based on their domains)
+     *
+     * @param   UserBackendInterface    $backend
+     * @param   User                    $user
+     *
+     * @return  bool
+     */
+    public static function isBackendResponsibleForUser(UserBackendInterface $backend, User $user)
+    {
+        $backendDomain = static::getBackendDomain($backend);
+        $userDomain = $user->getDomain();
+
+        if ($userDomain === null) {
+            // The user logs in as "jdoe", not as "jdoe@example.com" and there's no default domain.
+            // The backend is only responsible if its domain is also missing.
+            return $backendDomain === null;
+        } else {
+            // The user logs in as "jdoe@example.com" or "jdoe" with a default domain being configured.
+            return strtolower($userDomain) === strtolower($backendDomain);
+        }
+    }
+
+    /**
+     * Get the domain the given backend is responsible for (fall back to the default domain if any)
+     *
+     * @param   UserBackendInterface    $backend
+     *
+     * @return  string|null
+     */
+    public static function getBackendDomain(UserBackendInterface $backend)
+    {
+        $backendDomain = Config::app('authentication')->get($backend->getName(), 'domain');
+        return $backendDomain === null ? Config::app()->get('authentication', 'default_domain') : $backendDomain;
+    }
+
+    /**
+     * Get the user from the given username without its domain and the backend as fully assembled {@link User} object
+     *
+     * @param   string                  $localUsername
+     * @param   UserBackendInterface    $backend
+     *
+     * @return  User
+     */
+    public static function getUserFromBackend($localUsername, UserBackendInterface $backend)
+    {
+        $user = new User($localUsername);
+        $user->setDomain(static::getBackendDomain($backend));
+        return $user->setDefaultDomainIfNeeded();
+    }
 }

library/Icinga/User.php

@@ -17,13 +17,6 @@ use Icinga\Web\Navigation\Navigation;
  */
 class User
 {
-    /**
-     * Username
-     *
-     * @var string
-     */
-    protected $username;
-
     /**
      * Firstname
      *
@@ -45,6 +38,13 @@ class User
      */
     protected $email;
 
+    /**
+     * {@link username} without {@link domain}
+     *
+     * @var string
+     */
+    protected $localUsername;
+
     /**
      * Domain
      *
@@ -279,7 +279,7 @@ class User
      */
     public function getUsername()
     {
-        return $this->username;
+        return $this->domain === null ? $this->localUsername : $this->localUsername . '@' . $this->domain;
     }
 
     /**
@@ -289,7 +289,18 @@ class User
      */
     public function setUsername($name)
     {
-        $this->username = $name;
+        $parts = explode('\\', $name, 2);
+        if (count($parts) === 2) {
+            list($this->domain, $this->localUsername) = $parts;
+        } else {
+            $parts = explode('@', $name, 2);
+            if (count($parts) === 2) {
+                list($this->localUsername, $this->domain) = $parts;
+            } else {
+                $this->localUsername = $name;
+                $this->domain = null;
+            }
+        }
     }
 
     /**
@@ -354,7 +365,7 @@ class User
         if (filter_var($mail, FILTER_VALIDATE_EMAIL)) {
             $this->email = $mail;
         } else {
-            throw new InvalidArgumentException("Invalid mail given for user $this->username: $mail");
+            throw new InvalidArgumentException('Invalid mail given for user ' . $this->getUsername() . ': $mail');
         }
     }
 
@@ -378,6 +389,15 @@ class User
         return $this->domain;
     }
 
+    /**
+     * Get the local username, ie. the username without its domain
+     *
+     * @return string
+     */
+    public function getLocalUsername()
+    {
+        return $this->localUsername;
+    }
 
     /**
      * Set additional information about user