{-|

Copyright:

  This file is part of the package openid-connect.  It is subject to
  the license terms in the LICENSE file found in the top-level
  directory of this distribution and at:

    https://code.devalot.com/open/openid-connect

  No part of this package, including this file, may be copied,
  modified, propagated, or distributed except according to the terms
  contained in the LICENSE file.

License: BSD-2-Clause

-}
module OpenID.Connect.Authentication
  ( ClientAuthentication(..)
  , ClientSecret(..)
  , Credentials(..)
  , ClientID
  , ClientRedirectURI
  , AuthenticationRequest(..)
  ) where

--------------------------------------------------------------------------------
-- Imports:
import Crypto.JOSE.JWK (JWK)
import Data.ByteString (ByteString)
import Data.Text (Text)
import GHC.Generics (Generic)
import Network.HTTP.Types (QueryItem)
import qualified Network.URI as Network
import OpenID.Connect.JSON
import OpenID.Connect.Scope

--------------------------------------------------------------------------------
-- | Private values needed by the client in order to authenticate with
-- the provider.
--
-- The method of authentication is established when the client
-- registers with the provider.
--
-- @since 0.1.0.0
data ClientSecret
  = AssignedSecretText Text
    -- ^ A @client_secret@ created by the provider and given to the
    -- client to use during authentication.
    --
    -- This is the most common way to authenticate with a provider.

  | AssignedAssertionText Text
    -- ^ A @client_secret@ created by the provider and given to the
    -- client.  The client must create a JWT and use the
    -- @client_secret@ to calculate a message authentication code for
    -- the JWT.

  | AssertionPrivateKey JWK
    -- ^ A private key that is solely in the client's possession.  The
    -- provider holds the public key portion of the given key.
    --
    -- The client creates and signs a JWT in order to authenticate.

--------------------------------------------------------------------------------
-- | A @client_id@ assigned by the provider.
--
-- @since 0.1.0.0
type ClientID = Text

--------------------------------------------------------------------------------
-- | The client (relying party) redirection URL previously registered
-- with the OpenID Provider (i.e. a URL to an endpoint on your web
-- site that receives authentication details from the provider via the
-- end-user's browser).
--
-- After the provider has authenticated the end-user, they will be
-- redirected to this URL to continue the flow.
--
-- NOTE: This URL must match exactly with the one registered with the
-- provider.  If they don't match the provider will not redirect the
-- end-user back to your site.
--
-- @since 0.1.0.0
type ClientRedirectURI = Network.URI

--------------------------------------------------------------------------------
-- | A complete set of credentials used by the client to authenticate
-- with the provider.
--
-- @since 0.1.0.0
data Credentials = Credentials
  { assignedClientId :: ClientID
    -- ^ The provider-assigned @client_id@.

  , clientSecret :: ClientSecret
    -- ^ The @client_secret@ or other means of authenticating.

  , clientRedirectUri :: ClientRedirectURI
    -- ^ The @redirect_uri@ shared between the client and provider.
    -- This URI must be registered with the provider.
  }

--------------------------------------------------------------------------------
-- | §3.1.2.1.  Authentication Request.
--
-- The fields of this record are send to the provider by way of a URI
-- given to the end-user.
--
-- Clients can use the
-- 'OpenID.Connect.Client.Flow.AuthorizationCode.defaultAuthenticationRequest'
-- function to easily create a value of this type.
--
-- @since 0.1.0.0
data AuthenticationRequest = AuthenticationRequest
  { authRequestRedirectURI :: ClientRedirectURI
    -- ^ Where to redirect the end-user to after authentication.

  , authRequestClientId :: Text
    -- ^ The @client_id@ assigned by the provider.

  , authRequestScope :: Scope
    -- ^ The @scope@ to request.  The @openid@ scope is always part of
    -- this list.

  , authRequestResponseType :: ByteString
    -- ^ The @response_type@ parameter.

  , authRequestDisplay :: Maybe ByteString
    -- ^ The @display@ parameter.

  , authRequestPrompt :: Maybe ByteString
    -- ^ The @prompt@ parameter.

  , authRequestMaxAge :: Maybe Int
    -- ^ The @max_age@ parameter.

  , authRequestUiLocales :: Maybe Words
    -- ^ The @ui_locales@ parameter.

  , authRequestIdTokenHint :: Maybe ByteString
    -- ^ The @id_token_hint@ parameter.

  , authRequestLoginHint :: Maybe Text
    -- ^ The @login_hint@ parameter.

  , authRequestAcrValues :: Maybe Words
    -- ^ The @acr_values@ parameter.

  , authRequestOtherParams :: [QueryItem]
    -- ^ Any additional query parameters you wish to send to the
    -- provider.
  }

--------------------------------------------------------------------------------
-- | Methods that a client can use to authenticate with a provider.
--
-- Defined in OpenID Connect Core 1.0 §9.
--
-- @since 0.1.0.0
data ClientAuthentication
  = ClientSecretBasic
    -- ^ Send credentials using HTTP Basic Authentication.

  | ClientSecretPost
    -- ^ Send the credentials in the body of an HTTP POST.

  | ClientSecretJwt
    -- ^ Create a JWT and calculate a message authentication code
    -- using a shared secret.  The JWT confirms that the client is in
    -- possession of the shared secret.

  | PrivateKeyJwt
    -- ^ Create and sign a JWT using a private key.  The provider must
    -- already have access to the public key corresponding to the
    -- private key.

  | None
    -- ^ The Client does not authenticate itself at the Token
    -- Endpoint, either because it uses only the Implicit Flow (and so
    -- does not use the Token Endpoint) or because it is a Public
    -- Client with no Client Secret or other authentication mechanism.

  deriving stock (Generic, Eq, Show)
  deriving (ToJSON, FromJSON) via GenericJSON ClientAuthentication