{-# LANGUAGE OverloadedStrings #-}
module Yesod.Auth.OAuth2.GitLab
    ( oauth2GitLab
    , oauth2GitLabHostScopes
    , defaultHost
    , defaultScopes
    )
where

import Yesod.Auth.OAuth2.Prelude

import qualified Data.Text as T

newtype User = User Int

instance FromJSON User where
    parseJSON :: Value -> Parser User
parseJSON = String -> (Object -> Parser User) -> Value -> Parser User
forall a. String -> (Object -> Parser a) -> Value -> Parser a
withObject String
"User" ((Object -> Parser User) -> Value -> Parser User)
-> (Object -> Parser User) -> Value -> Parser User
forall a b. (a -> b) -> a -> b
$ \Object
o -> Int -> User
User (Int -> User) -> Parser Int -> Parser User
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Object
o Object -> Text -> Parser Int
forall a. FromJSON a => Object -> Text -> Parser a
.: Text
"id"

pluginName :: Text
pluginName :: Text
pluginName = Text
"gitlab"

defaultHost :: URI
defaultHost :: URI
defaultHost = URI
"https://gitlab.com"

defaultScopes :: [Text]
defaultScopes :: [Text]
defaultScopes = [Text
"read_user"]

-- | Authorize with @gitlab.com@ and @[\"read_user\"]@
--
-- To customize either of these values, use @'oauth2GitLabHostScopes'@ and pass
-- the default for the argument not being customized. Note that we require at
-- least @read_user@, so we can request the credentials identifier.
--
-- > oauth2GitLabHostScopes defaultHost ["api", "read_user"]
-- > oauth2GitLabHostScopes "https://gitlab.example.com" defaultScopes
--
oauth2GitLab :: YesodAuth m => Text -> Text -> AuthPlugin m
oauth2GitLab :: Text -> Text -> AuthPlugin m
oauth2GitLab = URI -> [Text] -> Text -> Text -> AuthPlugin m
forall m.
YesodAuth m =>
URI -> [Text] -> Text -> Text -> AuthPlugin m
oauth2GitLabHostScopes URI
defaultHost [Text]
defaultScopes

oauth2GitLabHostScopes
    :: YesodAuth m => URI -> [Text] -> Text -> Text -> AuthPlugin m
oauth2GitLabHostScopes :: URI -> [Text] -> Text -> Text -> AuthPlugin m
oauth2GitLabHostScopes URI
host [Text]
scopes Text
clientId Text
clientSecret =
    Text -> OAuth2 -> FetchCreds m -> AuthPlugin m
forall m.
YesodAuth m =>
Text -> OAuth2 -> FetchCreds m -> AuthPlugin m
authOAuth2 Text
pluginName OAuth2
oauth2 (FetchCreds m -> AuthPlugin m) -> FetchCreds m -> AuthPlugin m
forall a b. (a -> b) -> a -> b
$ \Manager
manager OAuth2Token
token -> do
        (User Int
userId, ByteString
userResponse) <-
            Text -> Manager -> OAuth2Token -> URI -> IO (User, ByteString)
forall a.
FromJSON a =>
Text -> Manager -> OAuth2Token -> URI -> IO (a, ByteString)
authGetProfile Text
pluginName Manager
manager OAuth2Token
token
            (URI -> IO (User, ByteString)) -> URI -> IO (User, ByteString)
forall a b. (a -> b) -> a -> b
$ URI
host
            URI -> ByteString -> URI
forall a. URIRef a -> ByteString -> URIRef a
`withPath` ByteString
"/api/v4/user"

        Creds m -> IO (Creds m)
forall (f :: * -> *) a. Applicative f => a -> f a
pure Creds :: forall master. Text -> Text -> [(Text, Text)] -> Creds master
Creds
            { credsPlugin :: Text
credsPlugin = Text
pluginName
            , credsIdent :: Text
credsIdent = String -> Text
T.pack (String -> Text) -> String -> Text
forall a b. (a -> b) -> a -> b
$ Int -> String
forall a. Show a => a -> String
show Int
userId
            , credsExtra :: [(Text, Text)]
credsExtra = OAuth2Token -> ByteString -> [(Text, Text)]
setExtra OAuth2Token
token ByteString
userResponse
            }
  where
    oauth2 :: OAuth2
oauth2 = OAuth2 :: Text -> Maybe Text -> URI -> URI -> Maybe URI -> OAuth2
OAuth2
        { oauthClientId :: Text
oauthClientId = Text
clientId
        , oauthClientSecret :: Maybe Text
oauthClientSecret = Text -> Maybe Text
forall a. a -> Maybe a
Just Text
clientSecret
        , oauthOAuthorizeEndpoint :: URI
oauthOAuthorizeEndpoint =
            URI
host
            URI -> ByteString -> URI
forall a. URIRef a -> ByteString -> URIRef a
`withPath` ByteString
"/oauth/authorize"
            URI -> [(ByteString, ByteString)] -> URI
forall a. URIRef a -> [(ByteString, ByteString)] -> URIRef a
`withQuery` [Text -> [Text] -> (ByteString, ByteString)
scopeParam Text
" " [Text]
scopes]
        , oauthAccessTokenEndpoint :: URI
oauthAccessTokenEndpoint = URI
host URI -> ByteString -> URI
forall a. URIRef a -> ByteString -> URIRef a
`withPath` ByteString
"/oauth/token"
        , oauthCallback :: Maybe URI
oauthCallback = Maybe URI
forall a. Maybe a
Nothing
        }