module Main where

import Prelude

import Data.Array (filter)
import Data.Maybe (Maybe(..))
import Data.String.Regex (Regex, test, match, replace, regex, parseFlags)
import Data.String.Regex.Flags (global, ignoreCase)
import Data.String.Regex.Unsafe (unsafeRegex)
import Effect (Effect)
import Effect.Console (log)

main :: Effect Unit
main = do
  -- This tests whether a pattern matches a string.
  let matchResult = test (unsafeRegex "p([a-z]+)ch" global) "peach"
  log $ show matchResult

  -- For other regex tasks, we'll use a compiled Regex.
  let r = unsafeRegex "p([a-z]+)ch" global

  -- Here's a match test like we saw earlier.
  log $ show $ test r "peach"

  -- This finds the match for the regex.
  case match r "peach punch" of
    Just matches -> log $ show $ matches
    Nothing -> log "No match found"

  -- The `match` function returns information about both
  -- the whole-pattern matches and the submatches.
  case match r "peach punch" of
    Just matches -> log $ show matches
    Nothing -> log "No match found"

  -- The `match` function with the global flag will find all matches.
  case match (unsafeRegex "p([a-z]+)ch" $ parseFlags "g") "peach punch pinch" of
    Just matches -> log $ show matches
    Nothing -> log "No matches found"

  -- The `replace` function can be used to replace subsets of strings.
  log $ replace r "<fruit>" "a peach"

  -- The `replace` function can also use a function to transform matched text.
  log $ replace r (\_ -> "PEACH") "a peach"