Edit.hs

{-# LANGUAGE OverloadedStrings #-}
module Main where
import System.Exit
import System.IO
import Data.Char
import Database.SQLite.Simple
import Text.RawString.QQ
import Data.Text (Text)
import qualified Data.Text as T
import Database.SQLite.Simple.Types


data User =
  User {
    userId :: Integer
  , username :: Text
  , shell :: Text
  , homedirectory :: Text
  , realName :: Text
  , phone :: Text
  } deriving (Eq, Show)

instance FromRow User where
  fromRow = User <$> field
                <*> field
                <*> field
                <*> field
                <*> field
                <*> field

instance ToRow User where
  toRow (User id_ username shell homeDir realName phone) =
    toRow (id_, username, shell, homeDir, realName, phone)


updateUser :: Query
updateUser = "UPDATE users\
             \ SET username = :uname, shell = :shell, homeDirectory = :hd, realName = :rname, phone = :ph WHERE username = :uname;"


main :: IO ()
main = do
  hSetBuffering stdin LineBuffering
  conn <- open "finger.db"
  putStrLn "Enter the username you want to edit or delete : "
  chknm <- getLine
  res <- query conn ("SELECT * from users where username=(?);") (Only (T.pack chknm)) :: IO [User]
  if null res then main else return ()
  putStrLn "Enter 1 to edit, 2 to delete : "
  choice <- getChar
  _ <- getChar
  case (ord choice) - 48 of
    1 -> return ()
    2 -> do
          execute conn ("DELETE from users where username=(?);") (Only (T.pack chknm))
          rows <- query_ conn ("SELECT * from users;") :: IO [User]
          mapM_ print (rows :: [User])
          Database.SQLite.Simple.close conn
          exitSuccess
    _ -> main
  putStrLn "Enter the shell : "
  ishell <- getLine
  putStrLn "Enter home directory : "
  ihome <- getLine
  putStrLn "Enter the real name : "
  irname <- getLine
  putStrLn "Enter the phone number : "
  iphone <- getLine
  executeNamed conn updateUser [":uname" := T.pack chknm, ":shell" := T.pack ishell, ":hd" := T.pack ihome, ":rname" := T.pack irname, ":ph" := T.pack iphone]
  rows <- query_ conn ("SELECT * from users;") :: IO [User]
  mapM_ print (rows :: [User])
  Database.SQLite.Simple.close conn