{-# LANGUAGE ViewPatterns, OverloadedStrings, FlexibleContexts #-}

module Utils
       ( showEntity
       , takeR
       ) where

import Data.Text (Text)
import qualified Data.Text as Text

import Data.PQueue.Prio.Max (MaxPQueue)
import qualified Data.PQueue.Prio.Max as MaxPQueue

import Data.Monoid (Monoid(..), (<>))

import Control.Monad.State.Class
import Control.Monad.Writer.Class

import Data.Set (Set)
import qualified Data.Set as Set

import Data.Sequence (Seq, ViewR(..), (|>))
import qualified Data.Sequence as Seq

import           Data.CaseInsensitive  ( CI )
import qualified Data.CaseInsensitive as CI

import Types

showEntity :: Entity -> Text
showEntity (Entity name number)
  | (Just (show -> n)) <- number = CI.original name <> " № " <> Text.pack n
  | otherwise = CI.original name

takeR :: Integer -> Seq a -> Seq a
takeR _ (Seq.viewr -> EmptyR) = Seq.empty
takeR n (Seq.viewr -> (xs :> x))
  | n <= 0 = Seq.empty
  | otherwise = takeR (n - 1) xs |> x