{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE StrictData        #-}

{-|
Module      : Headroom.UI.Progress
Description : UI component for displaying progress
Copyright   : (c) 2019-2020 Vaclav Svejcar
License     : BSD-3-Clause
Maintainer  : vaclav.svejcar@gmail.com
Stability   : experimental
Portability : POSIX

This component displays progress in format @[CURR of TOTAL]@.
-}

module Headroom.UI.Progress
  ( Progress(..)
  , zipWithProgress
  )
where

import           RIO
import qualified RIO.List                      as L
import qualified RIO.Text                      as T
import           Text.Printf                    ( printf )


-- | Progress indication. First argument is current progress, second the maximum
-- value.
data Progress = Progress Int Int
  deriving (Eq, Show)


instance Display Progress where
  textDisplay (Progress current total) = T.pack
    $ mconcat ["[", currentS, " of ", totalS, "]"]
   where
    format   = "%" <> (show . L.length $ totalS) <> "d"
    currentS = printf format current
    totalS   = show total


-- | Zips given list with the progress info.
--
-- >>> zipWithProgress ["a", "b"]
-- [(Progress 1 2,"a"),(Progress 2 2,"b")]
zipWithProgress :: [a]
                -- ^ list to zip with progress
                -> [(Progress, a)]
                -- ^ zipped result
zipWithProgress list = zip progresses list
 where
  listLength = L.length list
  progresses = fmap (`Progress` listLength) [1 .. listLength]