{-# OPTIONS_GHC -fno-warn-unused-matches #-}
{-# LANGUAGE TupleSections #-}
module Handler.Notes where

import Import
import Handler.Common (lookupPagingParams)
import qualified Data.Aeson as A
import qualified Data.Text as T
import           Yesod.RssFeed
import qualified Text.Blaze.Html5 as H

getNotesR :: UserNameP -> Handler Html
getNotesR unamep@(UserNameP uname) = do
  mauthuname <- maybeAuthUsername
  (limit', page') <- lookupPagingParams
  let queryp = "query"
  mquery <- lookupGetParam queryp
  let limit = maybe 20 fromIntegral limit'
      page  = maybe 1  fromIntegral page'
      mqueryp = fmap (queryp,) mquery
      isowner = Just uname == mauthuname
  (bcount, notes) <- runDB do
    Entity userId user <- getBy404 (UniqueUserName uname)
    let sharedp = if isowner then SharedAll else SharedPublic
    when (not isowner && userPrivacyLock user)
      (redirect (AuthR LoginR))
    getNoteList userId mquery sharedp limit page
  req <- getRequest
  mroute <- getCurrentRoute
  defaultLayout do
    rssLink (NotesFeedR unamep) "feed"
    let pager = $(widgetFile "pager")
        search = $(widgetFile "search")
        renderEl = "notes" :: Text
    $(widgetFile "notes")
    toWidgetBody [julius|
        app.userR = "@{UserR unamep}";
        app.dat.notes = #{ toJSON notes } || [];
        app.dat.isowner = #{ isowner };
    |]
    toWidget [julius|
      PS['Main'].renderNotes('##{rawJS renderEl}')(app.dat.notes)();
    |]

getNoteR :: UserNameP -> NtSlug -> Handler Html
getNoteR unamep@(UserNameP uname) slug = do
  mauthuname <- maybeAuthUsername
  let renderEl = "note" :: Text
      isowner = Just uname == mauthuname
  note <-
    runDB $
    do Entity userId user <- getBy404 (UniqueUserName uname)
       mnote <- getNote userId slug
       note <- maybe notFound pure mnote
       when (not isowner && (userPrivacyLock user || (not . noteShared . entityVal) note))
         (redirect (AuthR LoginR))
       pure note
  defaultLayout do
    $(widgetFile "note")
    toWidgetBody [julius|
        app.userR = "@{UserR unamep}";
        app.dat.note = #{ toJSON note } || [];
        app.dat.isowner = #{ isowner };
    |]
    toWidget [julius|
      PS['Main'].renderNote('##{rawJS renderEl}')(app.dat.note)();
    |]

getAddNoteSlimViewR :: Handler Html
getAddNoteSlimViewR = do
  Entity userId user <- requireAuth
  getAddNoteViewR (UserNameP (userName user))

getAddNoteViewR :: UserNameP -> Handler Html
getAddNoteViewR unamep@(UserNameP uname) = do
  userId <- requireAuthId
  note <- liftIO . _toNote userId =<< noteFormUrl
  let renderEl = "note" :: Text
      enote = Entity (NoteKey 0) note
  defaultLayout do
    $(widgetFile "note")
    toWidgetBody [julius|
        app.userR = "@{UserR unamep}";
        app.noteR = "@{NoteR unamep (noteSlug (entityVal enote))}";
        app.dat.note = #{ toJSON enote } || [];
    |]
    toWidget [julius|
      PS['Main'].renderNote('##{rawJS renderEl}')(app.dat.note)();
    |]

deleteDeleteNoteR :: Int64 -> Handler Html
deleteDeleteNoteR nid = do
  userId <- requireAuthId
  runDB do
    let k_nid = NoteKey nid
    _ <- requireResource userId k_nid
    delete k_nid
  return ""

postAddNoteR :: Handler Text
postAddNoteR = do
  noteForm <- requireCheckJsonBody
  _handleFormSuccess noteForm >>= \case
    Created nid -> sendStatusJSON created201 nid
    Updated _ -> sendResponseStatus noContent204 ()
    Failed s -> sendResponseStatus status400 s

requireResource :: UserId -> Key Note -> DBM Handler Note
requireResource userId k_nid = do
  nnote <- get404 k_nid
  if userId == noteUserId nnote
    then return nnote
    else notFound

_handleFormSuccess :: NoteForm -> Handler (UpsertResult (Key Note))
_handleFormSuccess noteForm = do
  userId <- requireAuthId
  note <- liftIO $ _toNote userId noteForm
  runDB (upsertNote userId knid note)
  where
    knid = NoteKey <$> (_id noteForm >>= \i -> if i > 0 then Just i else Nothing)

data NoteForm = NoteForm
  { _id :: Maybe Int64
  , _slug :: Maybe NtSlug
  , _title :: Maybe Text
  , _text :: Maybe Textarea
  , _isMarkdown :: Maybe Bool
  , _shared :: Maybe Bool
  , _created :: Maybe UTCTimeStr
  , _updated :: Maybe UTCTimeStr
  } deriving (Show, Eq, Read, Generic)

instance FromJSON NoteForm where parseJSON = A.genericParseJSON gNoteFormOptions
instance ToJSON NoteForm where toJSON = A.genericToJSON gNoteFormOptions

gNoteFormOptions :: A.Options
gNoteFormOptions = A.defaultOptions { A.fieldLabelModifier = drop 1 }

noteFormUrl :: Handler NoteForm
noteFormUrl = do
  title <- lookupGetParam "title"
  description <- lookupGetParam "description" <&> fmap Textarea
  isMarkdown <- lookupGetParam "isMarkdown" <&> fmap parseChk
  pure $ NoteForm
    { _id = Nothing
    , _slug = Nothing
    , _title = title
    , _text = description
    , _isMarkdown = isMarkdown
    , _shared = Nothing
    , _created = Nothing
    , _updated = Nothing
    }
  where
    parseChk s = s == "yes" || s == "on" || s == "true" || s == "1"

_toNote :: UserId -> NoteForm -> IO Note
_toNote userId NoteForm {..} = do
  time <- liftIO getCurrentTime
  slug <- maybe mkNtSlug pure _slug
  pure $
    Note
    { noteUserId = userId
    , noteSlug = slug
    , noteLength = length _text
    , noteTitle = fromMaybe "" _title
    , noteText = maybe "" unTextarea _text
    , noteIsMarkdown = Just True == _isMarkdown
    , noteShared = Just True == _shared
    , noteCreated = maybe time unUTCTimeStr _created
    , noteUpdated = maybe time unUTCTimeStr _updated
    }

noteToRssEntry :: UserNameP -> Entity Note -> FeedEntry (Route App)
noteToRssEntry usernamep (Entity entryId entry) =
  FeedEntry
  { feedEntryLink = NoteR usernamep (noteSlug entry)
  , feedEntryUpdated = noteUpdated entry
  , feedEntryTitle = noteTitle entry
  , feedEntryContent = toHtml (noteText entry)
  , feedEntryEnclosure = Nothing
  , feedEntryCategories = []
  }

getNotesFeedR :: UserNameP -> Handler RepRss
getNotesFeedR unamep@(UserNameP uname) = do
  mauthuname <- maybeAuthUsername
  (limit', page') <- lookupPagingParams
  mquery <- lookupGetParam "query"
  let limit = maybe 20 fromIntegral limit'
      page  = maybe 1   fromIntegral page'
      isowner = Just uname == mauthuname
  (_, notes) <- runDB do
      Entity userId user <- getBy404 (UniqueUserName uname)
      when (not isowner && userPrivacyLock user)
        (redirect (AuthR LoginR))
      getNoteList userId mquery SharedPublic limit page
  let (descr :: Html) = toHtml $ H.text (uname <> " notes")
      entries = map (noteToRssEntry unamep) notes
  updated <- case maximumMay (map feedEntryUpdated entries) of
                Nothing -> liftIO getCurrentTime
                Just m ->  return m
  rssFeed $
    Feed
    { feedTitle = uname <> " notes"
    , feedLinkSelf = NotesFeedR unamep
    , feedLinkHome = NotesR unamep
    , feedAuthor = uname
    , feedDescription = descr
    , feedLanguage = "en"
    , feedUpdated = updated
    , feedLogo = Nothing
    , feedEntries = entries
    }