--  eidolon -- A simple gallery in Haskell and Yesod
--  Copyright (C) 2015  Amedeo Molnár
--
--  This program is free software: you can redistribute it and/or modify
--  it under the terms of the GNU Affero General Public License as published
--  by the Free Software Foundation, either version 3 of the License, or
--  (at your option) any later version.
--
--  This program is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU Affero General Public License for more details.
--
--  You should have received a copy of the GNU Affero General Public License
--  along with this program.  If not, see <http://www.gnu.org/licenses/>.

module Handler.AlbumSettings where

import Import
import qualified Data.Text as T
import System.Directory
import System.FilePath
import qualified Data.List as L

getAlbumSettingsR :: AlbumId -> Handler Html
getAlbumSettingsR albumId = do
  tempAlbum <- runDB $ get albumId
  case tempAlbum of
    Just album -> do
      let ownerId = albumOwner album
      musername <- maybeAuthId
      case musername of
        Just username -> do
          (Just (Entity uId u)) <- runDB $ getBy $ UniqueUser username
          let ownerPresence = uId == ownerId
              presence = uId `elem` (albumShares album)
          if ownerPresence || presence
          then do
            entities <- runDB $ selectList [UserId !=. (albumOwner album)] [Desc UserName]
            let users = map (\u -> (userName $ entityVal u, entityKey u)) entities
            (albumSettingsWidget, enctype) <- generateFormPost $
              renderBootstrap3 BootstrapBasicForm $
              albumSettingsForm album albumId users
            defaultLayout $ do
              setTitle "Eidolon :: Album Settings"
              $(widgetFile "albumSettings")
          else do
            setMessage "You must own this album to change its settings"
            redirect $ AlbumR albumId
        Nothing -> do
          setMessage "You must be logged in to change settings"
          redirect $ AuthR LoginR
    Nothing -> do
      setMessage "This album does not exist"
      redirect HomeR

postAlbumSettingsR :: AlbumId -> Handler Html
postAlbumSettingsR albumId = do
  tempAlbum <- runDB $ get albumId
  case tempAlbum of
    Just album -> do
      let ownerId = albumOwner album
      owner <- runDB $ getJust ownerId
      let ownerName = userName owner
      musername <- maybeAuthId
      case musername of
        Just username -> do
          (Just (Entity uId u)) <- runDB $ getBy $ UniqueUser username
          let ownerPresence = uId == ownerId
              presence = uId `elem` albumShares album
          if ownerPresence || presence
          then do
            entities <- runDB $ selectList [UserId !=. (albumOwner album)] [Desc UserName]
            let users = map (\u -> (userName $ entityVal u, entityKey u)) entities
            ((result, _), _) <- runFormPost $
              renderBootstrap3 BootstrapBasicForm $
              albumSettingsForm album albumId users
            case result of
              FormSuccess temp -> do
                let newShares = L.sort $ albumShares temp
                let oldShares = L.sort $ albumShares album
                _ <- if
                  newShares /= oldShares
                  then do
                    link <- ($ AlbumR albumId) <$> getUrlRender
                    let rcptIds = L.nub $ newShares L.\\ oldShares
                    mapM (\id -> do
                      -- update userAlbums
                      user <- runDB $ getJust id
                      let oldAlbs = userAlbums user
                          newAlbs = albumId : oldAlbs
                      _ <- runDB $ update id [UserAlbums =. newAlbs]
                      -- send notification
                      let addr = userEmail user
                      sendMail addr "A new album was shared with you" $
                        [shamlet|
<h1>Hello #{userSlug user}!
<p>#{ownerName} was so kind to share his album #{albumTitle album} with you.
<p>You can find it
  <a href=#{link}>
    here
  .
                          |]
                      ) rcptIds
                  else  do
                    return [()]
                    -- nothing to do here
                _ <- runDB $ update albumId
                  [ AlbumTitle =. albumTitle temp
                  , AlbumShares =. newShares
                  , AlbumSamplePic =. albumSamplePic temp
                  ]
                setMessage "Album settings changed succesfully"
                redirect $ AlbumR albumId
              _ -> do
                setMessage "There was an error while changing the settings"
                redirect $ AlbumSettingsR albumId
          else do
            setMessage "You must own this album to change its settings"
            redirect $ AlbumR albumId
        Nothing -> do
          setMessage "You must be logged in to change settings"
          redirect $ AuthR LoginR
    Nothing -> do
      setMessage "This album does not exist"
      redirect HomeR

albumSettingsForm :: Album -> AlbumId -> [(Text, UserId)]-> AForm Handler Album
albumSettingsForm album albumId users = Album
  <$> areq textField (bfs ("Title" :: T.Text)) (Just $ albumTitle album)
  <*> pure (albumOwner album)
  <*> areq (userField users) (bfs ("Share this album with" :: T.Text)) (Just $ albumShares album)
  <*> pure (albumContent album)
  <*> aopt (selectField media) (bfs ("Sample picture" :: T.Text)) (Just $ albumSamplePic album)
  <*  bootstrapSubmit ("Change settings" :: BootstrapSubmit Text)
  where
    media = do
      entities <- runDB $ selectList [MediumAlbum ==. albumId] [Asc MediumTitle]
      optionsPairs $ map (\med -> (mediumTitle $ entityVal med, mediumThumb (entityVal med))) entities

getAlbumDeleteR :: AlbumId -> Handler Html
getAlbumDeleteR albumId = do
  tempAlbum <- runDB $ get albumId
  case tempAlbum of
    Just album -> do
      let ownerId = albumOwner album
      musername <- maybeAuthId
      case musername of
        Just username -> do
          (Just (Entity uId u)) <- runDB $ getBy $ UniqueUser username
          if uId == ownerId
          then do
            defaultLayout $ do
              setTitle $ toHtml ("Eidolon :: Delete album" `T.append` (albumTitle album))
              $(widgetFile "albumDelete")
          else do
            setMessage "You must own this album to delete it"
            redirect $ AlbumR albumId
        Nothing -> do
          setMessage "You must be logged in to delete albums"
          redirect $ AuthR LoginR
    Nothing -> do
      setMessage "This album does not exist"
      redirect HomeR

postAlbumDeleteR :: AlbumId -> Handler Html
postAlbumDeleteR albumId = do
  tempAlbum <- runDB $ get albumId
  case tempAlbum of
    Just album -> do
      let ownerId = albumOwner album
      owner <- runDB $ getJust ownerId
      musername <- maybeAuthId
      case musername of
        Just username -> do
          (Just (Entity uId u)) <- runDB $ getBy $ UniqueUser username
          if uId == ownerId
          then do
            confirm <- lookupPostParam "confirm"
            case confirm of
              Just "confirm" -> do
                -- remove album reference from user
                let albumList = userAlbums owner
                let newAlbumList = removeItem albumId albumList
                runDB $ update ownerId [UserAlbums =. newAlbumList]
                -- delete album content and its comments
                _ <- mapM (\a -> do
                  -- delete files
                  medium <- runDB $ getJust a
                  liftIO $ removeFile (normalise $ L.tail $ mediumPath medium)
                  liftIO $ removeFile (normalise $ L.tail $ mediumThumb medium)
                  liftIO $ removeFile (normalise $ L.tail $ mediumPreview medium)
                  -- delete comments
                  commEnts <- runDB $ selectList [CommentOrigin ==. a] []
                  _ <- mapM (\c -> do
                    children <- runDB $ selectList [CommentParent ==. (Just $ entityKey c)] []
                    _ <- mapM (\child -> do
                      -- delete comment children from elasticsearch and db
                      runDB $ delete $ entityKey child
                      ) children
                    -- delete comment from elasticsearch
                    runDB $ delete $ entityKey c) commEnts
                  runDB $ delete a
                  ) (albumContent album)
                -- delete album
                runDB $ delete albumId
                -- delete files
                liftIO $ removeDirectoryRecursive $ "static" </> "data" </> T.unpack (extractKey uId) </> T.unpack (extractKey albumId)
                -- outro
                setMessage "Album deleted succesfully"
                redirect HomeR
              _ -> do
                setMessage "You must confirm the deletion"
                redirect $ AlbumSettingsR albumId
          else do
            setMessage "You must own this album to delete it"
            redirect $ AlbumR albumId
        Nothing -> do
          setMessage "You must be logged in to delete albums"
          redirect $ AuthR LoginR
    Nothing -> do
      setMessage "This album does not exist"
      redirect HomeR