{-# LANGUAGE QuasiQuotes, TemplateHaskell, TypeFamilies #-}
module ~sitearg~
    ( ~sitearg~ (..)
    , ~sitearg~Route (..)
    , resources~sitearg~
    , Handler
    , maybeAuth
    , requireAuth
    , module Yesod
    , module Settings
    , module Model
    , StaticRoute (..)
    , AuthRoute (..)
    ) where

import Yesod
import Yesod.Mail
import Yesod.Helpers.Static
import Yesod.Helpers.Auth
import qualified Settings
import System.Directory
import qualified Data.ByteString.Lazy as L
import Yesod.WebRoutes
import Database.Persist.GenericSql
import Settings (hamletFile, cassiusFile, juliusFile)
import Model
import Control.Monad (join)
import Data.Maybe (isJust)

-- | The site argument for your application. This can be a good place to
-- keep settings and values requiring initialization before your application
-- starts running, such as database connections. Every handler will have
-- access to the data present here.
data ~sitearg~ = ~sitearg~
    { getStatic :: Static -- ^ Settings for static file serving.
    , connPool :: Settings.ConnectionPool -- ^ Database connection pool.
    }

-- | A useful synonym; most of the handler functions in your application
-- will need to be of this type.
type Handler = GHandler ~sitearg~ ~sitearg~

-- This is where we define all of the routes in our application. For a full
-- explanation of the syntax, please see:
-- http://docs.yesodweb.com/book/web-routes-quasi/
--
-- This function does three things:
--
-- * Creates the route datatype ~sitearg~Route. Every valid URL in your
--   application can be represented as a value of this type.
-- * Creates the associated type:
--       type instance Route ~sitearg~ = ~sitearg~Route
-- * Creates the value resources~sitearg~ which contains information on the
--   resources declared below. This is used in Controller.hs by the call to
--   mkYesodDispatch
--
-- What this function does *not* do is create a YesodSite instance for
-- ~sitearg~. Creating that instance requires all of the handler functions
-- for our application to be in scope. However, the handler functions
-- usually require access to the ~sitearg~Route datatype. Therefore, we
-- split these actions into two functions and place them in separate files.
mkYesodData "~sitearg~" [$parseRoutes|
/static StaticR Static getStatic
/auth   AuthR   Auth   getAuth

/favicon.ico FaviconR GET
/robots.txt RobotsR GET

/ RootR GET
|]

-- Please see the documentation for the Yesod typeclass. There are a number
-- of settings which can be configured by overriding methods here.
instance Yesod ~sitearg~ where
    approot _ = Settings.approot

    defaultLayout widget = do
        mmsg <- getMessage
        pc <- widgetToPageContent $ do
            widget
            addStyle $(Settings.cassiusFile "default-layout")
        hamletToRepHtml $(Settings.hamletFile "default-layout")

    -- This is done to provide an optimization for serving static files from
    -- a separate domain. Please see the staticroot setting in Settings.hs
    urlRenderOverride a (StaticR s) =
        Just $ uncurry (joinPath a Settings.staticroot) $ format s
      where
        format = formatPathSegments ss
        ss :: Site StaticRoute (String -> Maybe (GHandler Static ~sitearg~ ChooseRep))
        ss = getSubSite
    urlRenderOverride _ _ = Nothing

    -- The page to be redirected to when authentication is required.
    authRoute _ = Just $ AuthR LoginR

    -- This function creates static content files in the static folder
    -- and names them based on a hash of their content. This allows
    -- expiration dates to be set far in the future without worry of
    -- users receiving stale content.
    addStaticContent ext' _ content = do
        let fn = base64md5 content ++ '.' : ext'
        let statictmp = Settings.staticdir ++ "/tmp/"
        liftIO $ createDirectoryIfMissing True statictmp
        liftIO $ L.writeFile (statictmp ++ fn) content
        return $ Just $ Right (StaticR $ StaticRoute ["tmp", fn] [], [])

-- How to run database actions.
instance YesodPersist ~sitearg~ where
    type YesodDB ~sitearg~ = SqlPersist
    runDB db = fmap connPool getYesod >>= Settings.runConnectionPool db

instance YesodAuth ~sitearg~ where
    type AuthEntity ~sitearg~ = User
    type AuthEmailEntity ~sitearg~ = Email

    defaultDest _ = RootR

    getAuthId creds _extra = runDB $ do
        x <- getBy $ UniqueUser $ credsIdent creds
        case x of
            Just (uid, _) -> return $ Just uid
            Nothing -> do
                fmap Just $ insert $ User (credsIdent creds) Nothing

    openIdEnabled _ = True

    emailSettings _ = Just EmailSettings
        { addUnverified = \email verkey ->
            runDB $ insert $ Email email Nothing (Just verkey)
        , sendVerifyEmail = sendVerifyEmail'
        , getVerifyKey = runDB . fmap (join . fmap emailVerkey) . get
        , setVerifyKey = \eid key -> runDB $ update eid [EmailVerkey $ Just key]
        , verifyAccount = \eid -> runDB $ do
            me <- get eid
            case me of
                Nothing -> return Nothing
                Just e -> do
                    let email = emailEmail e
                    case emailUser e of
                        Just uid -> return $ Just uid
                        Nothing -> do
                            uid <- insert $ User email Nothing
                            update eid [EmailUser $ Just uid]
                            return $ Just uid
        , getPassword = runDB . fmap (join . fmap userPassword) . get
        , setPassword = \uid pass -> runDB $ update uid [UserPassword $ Just pass]
        , getEmailCreds = \email -> runDB $ do
            me <- getBy $ UniqueEmail email
            case me of
                Nothing -> return Nothing
                Just (eid, e) -> return $ Just EmailCreds
                    { emailCredsId = eid
                    , emailCredsAuthId = emailUser e
                    , emailCredsStatus = isJust $ emailUser e
                    , emailCredsVerkey = emailVerkey e
                    }
        , getEmail = runDB . fmap (fmap emailEmail) . get
        }

sendVerifyEmail' :: String -> String -> String -> GHandler Auth m ()
sendVerifyEmail' email _ verurl =
    liftIO $ renderSendMail Mail
            { mailHeaders =
                [ ("From", "noreply")
                , ("To", email)
                , ("Subject", "Verify your email address")
                ]
            , mailPlain = verurl
            , mailParts = return Part
                { partType = "text/html; charset=utf-8"
                , partEncoding = None
                , partDisposition = Inline
                , partContent = renderHamlet id [$hamlet|
%p Please confirm your email address by clicking on the link below.
%p
    %a!href=$verurl$ $verurl$
%p Thank you
|~~]
                }
            }