module Foundation where

import ClassyPrelude.Yesod
import Yesod.Auth
import Yesod.Auth.BrowserId
import Yesod.Auth.GoogleEmail
import Yesod.Default.Config
import Yesod.Default.Util (addStaticContentExternal)
import qualified Settings
import Settings.Development (development)
import qualified Database.Persist
import Settings.StaticFiles
import Settings (widgetFile, Extra (..))
import Model
import Text.Jasmine (minifym)
import Text.Hamlet (hamletFile)
import Yesod.Core.Types (Logger)
import Data.Slug (safeMakeSlug, HasGenIO (getGenIO), randomSlug, Slug)
import qualified System.Random.MWC as MWC
import Data.BlobStore
import Types

-- | 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 App = App
    { settings :: AppConfig DefaultEnv Extra
    , getStatic :: Static -- ^ Settings for static file serving.
    , connPool :: Database.Persist.PersistConfigPool Settings.PersistConf -- ^ Database connection pool.
    , httpManager :: Manager
    , persistConfig :: Settings.PersistConf
    , appLogger :: Logger
    , genIO :: !MWC.GenIO
    , blobStore :: !(BlobStore StoreKey)
    , progressMap :: !(IORef (IntMap Progress))
    , nextProgressKey :: !(IORef Int)
    }

data Progress = ProgressWorking !Text
              | ProgressDone !Text !(Route App)

instance HasBlobStore App StoreKey where
    getBlobStore = blobStore

instance HasGenIO App where
    getGenIO = genIO

instance HasHttpManager App where
    getHttpManager = httpManager

instance HasHackageRoot App where
    getHackageRoot = hackageRoot . appExtra . settings

-- This is where we define all of the routes in our application. For a full
-- explanation of the syntax, please see:
-- http://www.yesodweb.com/book/routing-and-handlers
--
-- Note that this is really half the story; in Application.hs, mkYesodDispatch
-- generates the rest of the code. Please see the linked documentation for an
-- explanation for this split.
mkYesodData "App" $(parseRoutesFile "config/routes")

deriving instance Show Progress

type Form x = Html -> MForm (HandlerT App IO) (FormResult x, Widget)

-- Please see the documentation for the Yesod typeclass. There are a number
-- of settings which can be configured by overriding methods here.
instance Yesod App where
    approot = ApprootMaster $ appRoot . settings

    -- Store session data on the client in encrypted cookies,
    -- default session idle timeout is 120 minutes
    makeSessionBackend _ = fmap Just $ defaultClientSessionBackend
        (120 * 60) -- 120 minutes
        "config/client_session_key.aes"

    defaultLayout widget = do
        master <- getYesod
        mmsg <- getMessage
        muser <- maybeAuth

        -- We break up the default layout into two components:
        -- default-layout is the contents of the body tag, and
        -- default-layout-wrapper is the entire page. Since the final
        -- value passed to hamletToRepHtml cannot be a widget, this allows
        -- you to use normal widget features in default-layout.

        cur <- getCurrentRoute
        pc <- widgetToPageContent $ do
            $(combineStylesheets 'StaticR
                [ css_normalize_css
                , css_bootstrap_css
                , css_bootstrap_responsive_css
                ])
            $(widgetFile "default-layout")

        mcurr <- getCurrentRoute
        let notHome = mcurr /= Just HomeR

        giveUrlRenderer $(hamletFile "templates/default-layout-wrapper.hamlet")

    -- This is done to provide an optimization for serving static files from
    -- a separate domain. Please see the staticRoot setting in Settings.hs
    urlRenderOverride y (StaticR s) =
        Just $ uncurry (joinPath y (Settings.staticRoot $ settings y)) $ renderRoute s
    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 =
        addStaticContentExternal minifym genFileName Settings.staticDir (StaticR . flip StaticRoute [])
      where
        -- Generate a unique filename based on the content itself
        genFileName lbs
            | development = "autogen-" ++ base64md5 lbs
            | otherwise   = base64md5 lbs

    -- Place Javascript at bottom of the body tag so the rest of the page loads first
    jsLoader _ = BottomOfBody

    -- What messages should be logged. The following includes all messages when
    -- in development, and warnings and errors in production.
    shouldLog _ source level =
        development || level == LevelWarn || level == LevelError || source == "CLEANUP"

    makeLogger = return . appLogger

    maximumContentLength _ (Just UploadStackageR) = Just 50000000
    maximumContentLength _ _ = Just 2000000

-- How to run database actions.
instance YesodPersist App where
    type YesodPersistBackend App = SqlPersistT
    runDB = defaultRunDB persistConfig connPool
instance YesodPersistRunner App where
    getDBRunner = defaultGetDBRunner connPool

instance YesodAuth App where
    type AuthId App = UserId

    -- Where to send a user after successful login
    loginDest _ = HomeR
    -- Where to send a user after logout
    logoutDest _ = HomeR

    getAuthId creds = do
        muid <- maybeAuthId
        join $ runDB $ case muid of
            Nothing -> do
                x <- getBy $ UniqueEmail $ credsIdent creds
                case x of
                    Just (Entity _ email) -> return $ return $ Just $ emailUser email
                    Nothing -> do
                        handle' <- getHandle (0 :: Int)
                        token <- getToken
                        userid <- insert User
                            { userHandle = handle'
                            , userDisplay = credsIdent creds
                            , userToken = token
                            }
                        void $ insert Email
                            { emailEmail = credsIdent creds
                            , emailUser = userid
                            }
                        return $ return $ Just userid
            Just uid -> do
                memail <- getBy $ UniqueEmail $ credsIdent creds
                case memail of
                    Nothing -> do
                        void $ insert Email
                            { emailEmail = credsIdent creds
                            , emailUser = uid
                            }
                        return $ do
                            setMessage $ toHtml $ concat
                                [ "Email address "
                                , credsIdent creds
                                , " added to your account."
                                ]
                            redirect ProfileR
                    Just _  -> invalidArgs $ return $ concat
                        [ "The email address "
                        , credsIdent creds
                        , " is already associated with a different account."
                        ]
      where
        handleBase = takeWhile (/= '@') (credsIdent creds)
        getHandle cnt | cnt > 50 = error "Could not get a unique slug"
        getHandle cnt = do
            slug <- lift $ safeMakeSlug handleBase (cnt > 0)
            muser <- getBy $ UniqueHandle slug
            case muser of
                Nothing -> return slug
                Just _  -> getHandle (cnt + 1)

    -- You can add other plugins like BrowserID, email or OAuth here
    authPlugins _ = [authBrowserId def, authGoogleEmail]

    authHttpManager = httpManager

getToken :: YesodDB App Slug
getToken =
    go (0 :: Int)
  where
    go cnt | cnt > 50 = error "Could not get a unique token"
    go cnt = do
        slug <- lift $ randomSlug 25
        muser <- getBy $ UniqueToken slug
        case muser of
            Nothing -> return slug
            Just _  -> go (cnt + 1)

-- This instance is required to use forms. You can modify renderMessage to
-- achieve customized and internationalized form validation messages.
instance RenderMessage App FormMessage where
    renderMessage _ _ = defaultFormMessage

-- | Get the 'Extra' value, used to hold data from the settings.yml file.
getExtra :: Handler Extra
getExtra = fmap (appExtra . settings) getYesod

-- Note: previous versions of the scaffolding included a deliver function to
-- send emails. Unfortunately, there are too many different options for us to
-- give a reasonable default. Instead, the information is available on the
-- wiki:
--
-- https://github.com/yesodweb/yesod/wiki/Sending-email