diff --git a/src/Models/AuthorizationCode.php b/src/Models/AuthorizationCode.php
new file mode 100644
index 0000000..18940db
--- /dev/null
+++ b/src/Models/AuthorizationCode.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace FoskyM\OAuthCenter\Models;
+
+use Flarum\Database\AbstractModel;
+
+class AuthorizationCode extends AbstractModel
+{
+    protected $table = 'oauth_authorization_codes';
+}
diff --git a/src/Models/Client.php b/src/Models/Client.php
new file mode 100644
index 0000000..ffe375d
--- /dev/null
+++ b/src/Models/Client.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace FoskyM\OAuthCenter\Models;
+
+use Flarum\Database\AbstractModel;
+
+class Client extends AbstractModel
+{
+    protected $table = 'oauth_clients';
+}
diff --git a/src/Models/Jwt.php b/src/Models/Jwt.php
new file mode 100644
index 0000000..bf19989
--- /dev/null
+++ b/src/Models/Jwt.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace FoskyM\OAuthCenter\Models;
+
+use Flarum\Database\AbstractModel;
+
+class Jwt extends AbstractModel
+{
+    protected $table = 'oauth_jwt';
+}
diff --git a/src/Models/RefreshToken.php b/src/Models/RefreshToken.php
new file mode 100644
index 0000000..e742c0c
--- /dev/null
+++ b/src/Models/RefreshToken.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace FoskyM\OAuthCenter\Models;
+
+use Flarum\Database\AbstractModel;
+
+class RefreshToken extends AbstractModel
+{
+    protected $table = 'oauth_refresh_tokens';
+}
diff --git a/src/Models/Scope.php b/src/Models/Scope.php
new file mode 100644
index 0000000..e5d108e
--- /dev/null
+++ b/src/Models/Scope.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace FoskyM\OAuthCenter\Models;
+
+use Flarum\Database\AbstractModel;
+
+class Scope extends AbstractModel
+{
+    protected $table = 'oauth_scopes';
+}
diff --git a/src/Storage.php b/src/Storage.php
index 72ad820..e196761 100644
--- a/src/Storage.php
+++ b/src/Storage.php
@@ -1,12 +1,126 @@
 <?php
 
 namespace FoskyM\OAuthCenter;
+use Flarum\Extend\Model;
+use Flarum\User\User;
+use OAuth2\OpenID\Storage\AuthorizationCodeInterface as OpenIDAuthorizationCodeInterface;
+use OAuth2\OpenID\Storage\UserClaimsInterface;
 use OAuth2\Storage\AccessTokenInterface;
 use OAuth2\Storage\ClientCredentialsInterface;
 use OAuth2\Storage\AuthorizationCodeInterface;
-abstract class Storage implements AccessTokenInterface,
-    ClientCredentialsInterface, AuthorizationCodeInterface
+use OAuth2\Storage\JwtBearerInterface;
+use OAuth2\Storage\PublicKeyInterface;
+use OAuth2\Storage\RefreshTokenInterface;
+use OAuth2\Storage\ScopeInterface;
+use OAuth2\Storage\UserCredentialsInterface;
+
+abstract class Storage implements
+    AuthorizationCodeInterface,
+    AccessTokenInterface,
+    ClientCredentialsInterface,
+    UserCredentialsInterface,
+    RefreshTokenInterface,
+    JwtBearerInterface,
+    ScopeInterface,
+    PublicKeyInterface,
+    UserClaimsInterface,
+    OpenIDAuthorizationCodeInterface
 {
+    /* OAuth2\Storage\ClientCredentialsInterface */
+    /**
+     * @param string $client_id
+     * @param null|string $client_secret
+     * @return bool
+     */
+    public function checkClientCredentials($client_id, $client_secret = null)
+    {
+        $client = Models\Client::where('client_id', $client_id)->first();
+
+        return $client && $client['client_secret'] == $client_secret;
+    }
+
+    /**
+     * @param string $client_id
+     * @return bool
+     */
+    public function isPublicClient($client_id)
+    {
+        $client = Models\Client::where('client_id', $client_id)->first();
+
+        if (!$client) {
+            return false;
+        }
+
+        return empty($client['client_secret']);
+    }
+
+    /**
+     * @param string $client_id
+     * @return array|mixed
+     */
+    public function getClientDetails($client_id)
+    {
+        $client = Models\Client::where('client_id', $client_id)->first();
+
+        return $client;
+    }
+
+    /**
+     * @param string $client_id
+     * @param null|string $client_secret
+     * @param null|string $redirect_uri
+     * @param null|array  $grant_types
+     * @param null|string $scope
+     * @param null|string $user_id
+     * @return bool
+     */
+    public function setClientDetails($client_id, $client_secret = null, $redirect_uri = null, $grant_types = null, $scope = null, $user_id = null)
+    {
+        // if it exists, update it.
+        if ($this->getClientDetails($client_id)) {
+            return Models\Client::where('client_id', $client_id)->update([
+                'client_secret' => $client_secret,
+                'redirect_uri' => $redirect_uri,
+                'grant_types' => $grant_types,
+                'scope' => $scope,
+                'user_id' => $user_id,
+            ]);
+        } else {
+            return Models\Client::create([
+                'client_id' => $client_id,
+                'client_secret' => $client_secret,
+                'redirect_uri' => $redirect_uri,
+                'grant_types' => $grant_types,
+                'scope' => $scope,
+                'user_id' => $user_id,
+            ]);
+        }
+    }
+
+    /**
+     * @param $client_id
+     * @param $grant_type
+     * @return bool
+     */
+    public function checkRestrictedGrantType($client_id, $grant_type)
+    {
+        $details = $this->getClientDetails($client_id);
+        if (isset($details['grant_types'])) {
+            $grant_types = explode(' ', $details['grant_types']);
+
+            return in_array($grant_type, (array) $grant_types);
+        }
+
+        // if grant_types are not defined, then none are restricted
+        return true;
+    }
+
+    /* OAuth2\Storage\AccessTokenInterface */
+
+    /**
+     * @param string $access_token
+     * @return array|bool|mixed|null
+     */
     public function getAccessToken($access_token)
     {
         if ($token = Models\AccessToken::where('access_token', $access_token)->first()) {
@@ -16,6 +130,14 @@ abstract class Storage implements AccessTokenInterface,
         return false;
     }
 
+    /**
+     * @param string $access_token
+     * @param mixed  $client_id
+     * @param mixed  $user_id
+     * @param int    $expires
+     * @param string $scope
+     * @return bool
+     */
     public function setAccessToken($access_token, $client_id, $user_id, $expires, $scope = null)
     {
         $expires = date('Y-m-d H:i:s', $expires);
@@ -38,8 +160,400 @@ abstract class Storage implements AccessTokenInterface,
         }
     }
 
+    /**
+     * @param $access_token
+     * @return bool
+     */
     public function unsetAccessToken($access_token)
     {
         return Models\AccessToken::where('access_token', $access_token)->delete();
     }
+
+    /* OAuth2\Storage\AuthorizationCodeInterface */
+    /**
+     * @param string $code
+     * @return mixed
+     */
+    public function getAuthorizationCode($code)
+    {
+        if ($code = Models\AuthorizationCode::where('authorization_code', $code)->first()) {
+            // convert date string back to timestamp
+            $code['expires'] = strtotime($code['expires']);
+        }
+
+        return $code;
+    }
+
+    /**
+     * @param string $code
+     * @param mixed  $client_id
+     * @param mixed  $user_id
+     * @param string $redirect_uri
+     * @param int    $expires
+     * @param string $scope
+     * @param string $id_token
+     * @return bool|mixed
+     */
+    public function setAuthorizationCode($code, $client_id, $user_id, $redirect_uri, $expires, $scope = null, $id_token = null, $code_challenge = null, $code_challenge_method = null)
+    {
+        if (func_num_args() > 6) {
+            // we are calling with an id token
+            return call_user_func_array(array($this, 'setAuthorizationCodeWithIdToken'), func_get_args());
+        }
+
+        // convert expires to datestring
+        $expires = date('Y-m-d H:i:s', $expires);
+
+        // if it exists, update it.
+        if ($this->getAuthorizationCode($code)) {
+            return Models\AuthorizationCode::where('authorization_code', $code)->update([
+                'client_id' => $client_id,
+                'user_id' => $user_id,
+                'redirect_uri' => $redirect_uri,
+                'expires' => $expires,
+                'scope' => $scope
+            ]);
+
+        } else {
+            return Models\AuthorizationCode::create([
+                'authorization_code' => $code,
+                'client_id' => $client_id,
+                'user_id' => $user_id,
+                'redirect_uri' => $redirect_uri,
+                'expires' => $expires,
+                'scope' => $scope
+            ]);
+        }
+
+    }
+
+    /**
+     * @param string $code
+     * @param mixed  $client_id
+     * @param mixed  $user_id
+     * @param string $redirect_uri
+     * @param string $expires
+     * @param string $scope
+     * @param string $id_token
+     * @return bool
+     */
+    private function setAuthorizationCodeWithIdToken($code, $client_id, $user_id, $redirect_uri, $expires, $scope = null, $id_token = null, $code_challenge = null, $code_challenge_method = null)
+    {
+        // convert expires to datestring
+        $expires = date('Y-m-d H:i:s', $expires);
+
+        // if it exists, update it.
+        if ($this->getAuthorizationCode($code)) {
+            return Models\AuthorizationCode::where('authorization_code', $code)->update([
+                'client_id' => $client_id,
+                'user_id' => $user_id,
+                'redirect_uri' => $redirect_uri,
+                'expires' => $expires,
+                'scope' => $scope,
+                'id_token' => $id_token,
+                'code_challenge' => $code_challenge,
+                'code_challenge_method' => $code_challenge_method
+            ]);
+        } else {
+            return Models\AuthorizationCode::create([
+                'authorization_code' => $code,
+                'client_id' => $client_id,
+                'user_id' => $user_id,
+                'redirect_uri' => $redirect_uri,
+                'expires' => $expires,
+                'scope' => $scope,
+                'id_token' => $id_token,
+                'code_challenge' => $code_challenge,
+                'code_challenge_method' => $code_challenge_method
+            ]);
+        }
+    }
+
+    /**
+     * @param string $code
+     * @return bool
+     */
+    public function expireAuthorizationCode($code)
+    {
+        return Models\AuthorizationCode::where('authorization_code', $code)->delete();
+    }
+
+    /* OAuth2\Storage\RefreshTokenInterface */
+
+    /**
+     * @param string $refresh_token
+     * @return bool|mixed
+     */
+    public function getRefreshToken($refresh_token)
+    {
+        $token = Models\RefreshToken::where('refresh_token', $refresh_token)->first();
+
+        if ($token) {
+            // convert expires to epoch time
+            $token['expires'] = strtotime($token['expires']);
+        }
+
+        return $token;
+    }
+
+    /**
+     * @param string $refresh_token
+     * @param mixed  $client_id
+     * @param mixed  $user_id
+     * @param string $expires
+     * @param string $scope
+     * @return bool
+     */
+    public function setRefreshToken($refresh_token, $client_id, $user_id, $expires, $scope = null)
+    {
+        // convert expires to datestring
+        $expires = date('Y-m-d H:i:s', $expires);
+
+        return Models\RefreshToken::create([
+            'refresh_token' => $refresh_token,
+            'client_id' => $client_id,
+            'user_id' => $user_id,
+            'expires' => $expires,
+            'scope' => $scope
+        ]);
+    }
+
+    /**
+     * @param string $refresh_token
+     * @return bool
+     */
+    public function unsetRefreshToken($refresh_token)
+    {
+        return Models\RefreshToken::where('refresh_token', $refresh_token)->delete();
+    }
+
+    /* OAuth2\Storage\UserCredentialsInterface */
+    /**
+     * @param string $username
+     * @param string $password
+     * @return bool
+     */
+    public function checkUserCredentials($username, $password)
+    {
+        if ($user = User::where('username', $username)->first()) {
+            return $user->checkPassword($password);
+        }
+
+        return false;
+    }
+
+    /**
+     * @param string $username
+     * @return array|bool
+     */
+    public function getUserDetails($username)
+    {
+        return User::where('username', $username)->first();
+    }
+
+    /**
+     * @param mixed  $user_id
+     * @param string $claims
+     * @return array|bool
+     */
+    public function getUserClaims($user_id, $claims)
+    {
+        if (!$userDetails = $this->getUserDetails($user_id)) {
+            return false;
+        }
+
+        $claims = explode(' ', trim($claims));
+        $userClaims = array();
+
+        // for each requested claim, if the user has the claim, set it in the response
+        $validClaims = explode(' ', self::VALID_CLAIMS);
+        foreach ($validClaims as $validClaim) {
+            if (in_array($validClaim, $claims)) {
+                if ($validClaim == 'address') {
+                    // address is an object with subfields
+                    $userClaims['address'] = $this->getUserClaim($validClaim, $userDetails['address'] ?: $userDetails);
+                } else {
+                    $userClaims = array_merge($userClaims, $this->getUserClaim($validClaim, $userDetails));
+                }
+            }
+        }
+
+        return $userClaims;
+    }
+
+    /**
+     * @param string $claim
+     * @param array  $userDetails
+     * @return array
+     */
+    protected function getUserClaim($claim, $userDetails)
+    {
+        $userClaims = array();
+        $claimValuesString = constant(sprintf('self::%s_CLAIM_VALUES', strtoupper($claim)));
+        $claimValues = explode(' ', $claimValuesString);
+
+        foreach ($claimValues as $value) {
+            $userClaims[$value] = isset($userDetails[$value]) ? $userDetails[$value] : null;
+        }
+
+        return $userClaims;
+    }
+
+    /* OAuth2\Storage\ScopeInterface */
+
+    /**
+     * @param string $scope
+     * @return bool
+     */
+    public function scopeExists($scope)
+    {
+        $scope = explode(' ', $scope);
+
+        if ($count = Models\Scope::whereIn('scope', $scope)->count()) {
+            return $count == count($scope);
+        }
+
+        return false;
+    }
+
+    /**
+     * @param mixed $client_id
+     * @return null|string
+     */
+    public function getDefaultScope($client_id = null)
+    {
+        if ($result = Models\Scope::where('is_default', true)->get()) {
+            $defaultScope = array_map(function ($row) {
+                return $row['scope'];
+            }, $result);
+
+            return implode(' ', $defaultScope);
+        }
+
+        return null;
+    }
+
+    /* OAuth2\Storage\JwtBearerInterface */
+
+    /**
+     * @param mixed $client_id
+     * @param $subject
+     * @return string
+     */
+    public function getClientKey($client_id, $subject)
+    {
+        $jwt = Models\Jwt::where('client_id', $client_id)->where('subject', $subject)->first();
+
+        return $jwt->public_key;
+    }
+
+    /**
+     * @param mixed $client_id
+     * @return bool|null
+     */
+    public function getClientScope($client_id)
+    {
+        if (!$clientDetails = $this->getClientDetails($client_id)) {
+            return false;
+        }
+
+        if (isset($clientDetails['scope'])) {
+            return $clientDetails['scope'];
+        }
+
+        return null;
+    }
+
+    /**
+     * @param mixed $client_id
+     * @param $subject
+     * @param $audience
+     * @param $expires
+     * @param $jti
+     * @return array|null
+     */
+    public function getJti($client_id, $subject, $audience, $expires, $jti)
+    {
+        /*$jti = Models\Jti::where('issuer', $client_id)
+            ->where('subject', $subject)
+            ->where('audience', $audience)
+            ->where('expires', $expires)
+            ->where('jti', $jti)
+            ->first();
+
+        if ($jti) {
+            return array(
+                'issuer' => $jti['issuer'],
+                'subject' => $jti['subject'],
+                'audience' => $jti['audience'],
+                'expires' => $jti['expires'],
+                'jti' => $jti['jti'],
+            );
+        }*/
+
+        return null;
+    }
+
+    /**
+     * @param mixed $client_id
+     * @param $subject
+     * @param $audience
+     * @param $expires
+     * @param $jti
+     * @return bool
+     */
+    public function setJti($client_id, $subject, $audience, $expires, $jti)
+    {
+        /*return Models\Jti::create([
+            'issuer' => $client_id,
+            'subject' => $subject,
+            'audience' => $audience,
+            'expires' => $expires,
+            'jti' => $jti,
+        ]);*/
+    }
+
+    /* OAuth2\Storage\PublicKeyInterface */
+
+    /**
+     * @param mixed $client_id
+     * @return mixed
+     */
+    public function getPublicKey($client_id = null)
+    {
+        /*$result = Models\PublicKey::where('client_id', $client_id)->first();
+
+        if ($result) {
+            return $result['public_key'];
+        }*/
+    }
+
+    /**
+     * @param mixed $client_id
+     * @return mixed
+     */
+    public function getPrivateKey($client_id = null)
+    {
+        /*$result = Models\PublicKey::where('client_id', $client_id)->first();
+
+        if ($result) {
+            return $result['private_key'];
+        }*/
+    }
+
+    /**
+     * @param mixed $client_id
+     * @return string
+     */
+    public function getEncryptionAlgorithm($client_id = null)
+    {
+        /*$result = Models\PublicKey::where('client_id', $client_id)->first();
+
+        if ($result) {
+            return $result['encryption_algorithm'];
+        }*/
+
+        return 'RS256';
+    }
+
 }