{-# OPTIONS_HADDOCK show-extensions #-}

-- |
-- Module      :  CLI.Arguments
-- Copyright   :  (c) OleksandrZhabenko 2021
-- License     :  MIT
-- Stability   :  Experimental
-- Maintainer  :  olexandr543@yahoo.com
--
-- A library to process command line arguments in some more convenient way.

module CLI.Arguments where

import Data.Monoid (mappend)
import GHC.Arr
import Data.List (sortBy)

data Arguments =
  A String
  | B Int String [String]
  | C String [String]
      deriving Eq

type Args = [Arguments]

type Specification = (Delimiter,GQtyArgs)

type CLSpecifications = [Specification]

type Delimiter = String

type GQtyArgs = Int

instance Show Arguments where
  show (A xs) = xs
  show (B n ys yss) = ' ':ys `mappend` concatMap (\xs ->' ':show xs) (take n yss)
  show (C xs xss) = ' ':xs `mappend` concatMap (\ys ->' ':show ys) xss `mappend` (' ':xs)

isA :: Arguments -> Bool
isA (A _) = True
isA _ = False

isB :: Arguments -> Bool
isB (B _ _ _) = True
isB _ = False

isC :: Arguments -> Bool
isC (C _ _) = True
isC _ = False

nullArguments :: Arguments -> Bool
nullArguments (A xs) = null xs
nullArguments (B n ys yss) = n /= length yss || null ys  || null yss
nullArguments (C xs xss) = null xs || null xss

notNullArguments :: Arguments -> Bool
notNullArguments (A (_:_)) =  True
notNullArguments (A _) = False
notNullArguments (B n (_:_) yss@(_:_)) = n == length yss
notNullArguments (B _ _ _) = False
notNullArguments (C (_:_) (_:_)) = True
notNullArguments _ = False

b1Args2AArgs :: Arguments -> Arguments
b1Args2AArgs b@(B n _ [ys])
 | n < 1 = A ys
 | otherwise = b
b1Args2AArgs x = x

args2Args
  :: CLSpecifications
  -> [String]
  ->  Args
args2Args (t@(xs,n):ts) xss@(js:jss)
  | n < 0 = C xs qss:args2Args ts (kss `mappend` rss)
  | n == 0 = A js:args2Args ts jss
  | otherwise = B n xs vss:args2Args ts (kss `mappend` zss)
      where (kss,uss) = break (== xs) xss
            wss = drop 1 uss
            (qss,pss) = break (== xs) wss
            rss = drop 1 pss
            (vss,zss) = splitAt n wss
args2Args [] xss = map A xss
args2Args _ [] = []

args2Args3'
  :: (Args,Args,Args)
  -> CLSpecifications
  -> [String]
  ->  (Args,Args,Args)
args2Args3' (w1,w2,w3) (t@(xs,n):ts) xss@(js:jss)
  | n < 0 = args2Args3' (w1,w2,C xs qss:w3) ts (kss `mappend` rss)
  | n == 0 = args2Args3' (A js:w1,w2,w3) ts jss
  | otherwise = args2Args3' (w1,B n xs vss:w2,w3) ts (kss `mappend` zss)
      where (kss,uss) = break (== xs) xss
            wss = drop 1 uss
            (qss,pss) = break (== xs) wss
            rss = drop 1 pss
            (vss,zss) = splitAt n wss
args2Args3' (w1,w2,w3) [] xss = (map A xss `mappend` w1,w2,w3)
args2Args3' (w1,w2,w3) _ [] = (w1,w2,w3)

args2Args3
  :: CLSpecifications
  -> [String]
  -> (Args,Args,Args)
args2Args3 = args2Args3' ([],[],[])
{-# INLINE args2Args3 #-}

-- | This function can actually parse the command line arguments being the ['String'] so that some of them will disappear
-- because of the 'CLSpecifications' provided and the order of the arguments.
args2ArgsFiltered
  :: CLSpecifications
  -> [String]
  -> Args
args2ArgsFiltered ts = filter notNullArguments . map b1Args2AArgs . args2Args ts
{-# INLINE args2ArgsFiltered #-}

takeCs
  :: CLSpecifications
  -> [String]
  -> Args
takeCs ts = filter (\x -> notNullArguments x && isC x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeCs #-}

takeBs
  :: CLSpecifications
  -> [String]
  -> Args
takeBs ts = filter (\x -> notNullArguments x && isB x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeBs #-}

takeAs
  :: CLSpecifications
  -> [String]
  -> Args
takeAs ts = filter (\x -> notNullArguments x && isA x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeAs #-}

------------------------------------------------------

takeCsSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'C's.
  -> CLSpecifications
  -> [String]
  -> Args
takeCsSortedBy f ts = sortBy f . filter (\x -> notNullArguments x && isC x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeCsSortedBy #-}

takeBsSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'B's.
  -> CLSpecifications
  -> [String]
  -> Args
takeBsSortedBy f ts = sortBy f . filter (\x -> notNullArguments x && isB x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeBsSortedBy #-}

takeAsSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'A's.
  -> CLSpecifications
  -> [String]
  -> Args
takeAsSortedBy f ts = sortBy f . filter (\x -> notNullArguments x && isA x) . map b1Args2AArgs . args2Args ts
{-# INLINE takeAsSortedBy #-}

------------------------------------------------------

takeCsArr
  :: CLSpecifications
  -> [String]
  -> Array Int Arguments
takeCsArr ts xss
 | null xss = error "CLI.Arguments.takeCsArr: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = filter (\x -> notNullArguments x && isC x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeCsArr #-}

takeBsArr
  :: CLSpecifications
  -> [String]
  -> Array Int Arguments
takeBsArr ts xss
 | null xss = error "CLI.Arguments.takeBsArr: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = filter (\x -> notNullArguments x && isB x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeBsArr #-}

takeAsArr
  :: CLSpecifications
  -> [String]
  -> Array Int Arguments
takeAsArr ts xss
 | null xss = error "CLI.Arguments.takeBsArr: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = filter (\x -> notNullArguments x && isA x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeAsArr #-}

---------------------------------------------------

takeCsArrSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'C's.
  -> CLSpecifications
  -> [String]
  -> Array Int Arguments
takeCsArrSortedBy f ts xss
 | null xss = error "CLI.Arguments.takeCsArrSortedBy: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = sortBy f . filter (\x -> notNullArguments x && isC x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeCsArrSortedBy #-}

takeBsArrSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'B's.
  -> CLSpecifications
  -> [String]
  -> Array Int Arguments
takeBsArrSortedBy f ts xss
 | null xss = error "CLI.Arguments.takeBsArrSortedBy: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = sortBy f . filter (\x -> notNullArguments x && isB x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeBsArrSortedBy #-}

takeAsArrSortedBy
  :: (Arguments -> Arguments -> Ordering) -- ^ A 'compare'-like implementation for 'Arguments'. If needed you can implement your own 'Ord' instance for 'Arguments' and use it here. Here can be partial, just for 'A's.
  -> CLSpecifications
  -> [String]
  -> Array Int Arguments
takeAsArrSortedBy f ts xss
 | null xss = error "CLI.Arguments.takeBsArrSortedBy: Empty list of 'String's."
 | otherwise = listArray (0,l-1) js
     where js = sortBy f . filter (\x -> notNullArguments x && isA x) . map b1Args2AArgs . args2Args ts $ xss
           l = length js
{-# INLINE takeAsArrSortedBy #-}