{-# OPTIONS_GHC -funbox-strict-fields #-}
-- | Common supports the Lazy Parsec backend.  It defines all the data
-- types except Pattern and exports everything but the contructors of
-- Pattern.
module Text.Regex.Parsec.Common where

import Data.IntMap(IntMap)
import Text.ParserCombinators.Parsec(GenParser)
import Text.Regex.Parsec.Pattern(Pattern)

-- | 'RegexOption' control whether the pattern is multiline or
-- case-sensitive like Text.Regex and whether to capture the subgroups
-- (\1, \2, etc).
data CompOption = CompOption {multiline :: Bool
                             ,caseSensitive :: Bool
                             ,captureGroups :: Bool
                             ,strategy::RegexOptionStrategy}

data RegexOptionStrategy = Find_LongestMatch 
                         | Find_FirstLeft 
                         | Find_FirstRight 
                         | Find_All

newtype ExecOption = ExecOption ()
{-
-- | This is a convenience value of RegexOption with multiline,
-- caseSensitive, and captureGroups all True and longestMatch False.
defaultRegexOption :: RegexOption
defaultRegexOption = RegexOption {multiline = True
                                 ,caseSensitive = True
                                 ,captureGroups = True
                                 ,strategy = Find_LongestMatch
                                 }
-}

-- | 'FullState' is the opaque data type used to hold the RegexParser
-- state and a user defined state.
data FullState userStateType = FullState {userState :: !userStateType
                                         ,accepted :: !Int
                                         ,openSub :: !(IntMap (String,Int))
                                         ,closedSub :: !MatchedStrings
                                         ,posixSub :: !Opened}

data Opened = Opened [Closed] Int (String,Int) Opened | EndOpened [Closed] deriving (Show)
data Closed = Closed [Closed] Int (String,(Int,Int)) deriving (Show)

-- | 'MatchedStrings' is an IntMap where the keys are PatternIndex
-- numbers and the values are completed substring captures.
--
-- This has now been augmented to also remember the offset and length
-- of the matched string.
type MatchedStrings = IntMap (String,(Int,Int))

-- | 'RegexParser' is the type of CharParser that uses the state from this module.
type RegexParser userState = GenParser Char (FullState userState)

type RegexP = RegexParser () [MatchedStrings]
type RegexPS s = RegexParser s [MatchedStrings]
type BoolMultiline = Bool
type BoolCaseSensitive = Bool
type StringRegex = String
type StringInput = String
type StringBeforeMatch = String
type StringOfMatch = String
type StringAfterMatch = String
type StringSubgroups = String
type StringSubPattern = String
type AboutMatch = (StringBeforeMatch,StringOfMatch,StringAfterMatch,[StringSubgroups])

-- | Datatype memo-izing the parsed regular expression and meta-data
data Regex = Regex {asString::StringRegex,asPattern::Pattern
                   ,capture::RegexP,capture'::RegexPS ShowS
                   ,noCapture::RegexP,noCapture'::RegexPS ([String]->[String])
                   ,userInt :: RegexPS Int
                   ,allMatches::RegexP,frontAnchor::Bool
                   ,groups::Int}