{-# LANGUAGE DeriveDataTypeable #-}

{- |

Module : $Header$

Description : Morphism of Common Logic

Copyright : (c) Uni Bremen DFKI 2010

License : GPLv2 or higher, see LICENSE.txt

Maintainer : eugenk@informatik.uni-bremen.de

Stability : experimental

Portability : non-portable (via Logic.Logic)

Morphism of Common Logic

-}

module CommonLogic.Morphism

( Morphism (..)

, pretty -- pretty printing

, idMor -- identity morphism

, isLegalMorphism -- check if morhpism is ok

, composeMor -- composition

, inclusionMap -- inclusion map

, mkMorphism -- create Morphism

, mapSentence -- map of sentences

, applyMap -- application function for maps

, applyMorphism -- application function for morphism

, morphismUnion

) where

import qualified Data.Map as Map

import qualified Data.Set as Set

import qualified Common.Result as Result

import Common.Id as Id

import Common.Result

import Common.Doc

import Common.DocUtils

import CommonLogic.AS_CommonLogic as AS

import CommonLogic.Sign as Sign

import Control.Monad (unless)

import Data.Data

-- maps of sets

data Morphism = Morphism

{ source :: Sign

, target :: Sign

, propMap :: Map.Map Id Id

} deriving (Eq, Ord, Show, Typeable)

instance Pretty Morphism where

pretty = printMorphism

-- | Constructs an id-morphism

idMor :: Sign -> Morphism

idMor a = inclusionMap a a

-- | Determines whether a morphism is valid

isLegalMorphism :: Morphism -> Result ()

isLegalMorphism pmor =

let psource = allItems $ source pmor

ptarget = allItems $ target pmor

pdom = Map.keysSet $ propMap pmor

pcodom = Set.map (applyMorphism pmor) psource

in unless (Set.isSubsetOf pcodom ptarget && Set.isSubsetOf pdom psource) $

fail "illegal CommonLogic morphism"

-- | Application funtion for morphisms

applyMorphism :: Morphism -> Id -> Id

applyMorphism mor idt = Map.findWithDefault idt idt $ propMap mor

-- | Application function for propMaps

applyMap :: Map.Map Id Id -> Id -> Id

applyMap pmap idt = Map.findWithDefault idt idt pmap

-- | Composition of morphisms in propositional Logic

composeMor :: Morphism -> Morphism -> Result Morphism

composeMor f g =

let fSource = source f

gTarget = target g

fMap = propMap f

gMap = propMap g

in return Morphism

{ source = fSource

, target = gTarget

, propMap = if Map.null gMap then fMap else

Set.fold ( \ i -> let j = applyMap gMap (applyMap fMap i) in

if i == j then id else Map.insert i j)

Map.empty $ allItems fSource }

-- | Pretty printing for Morphisms

printMorphism :: Morphism -> Doc

printMorphism m = pretty (source m) <> text "-->" <> pretty (target m)

<> vcat (map ( \ (x, y) -> lparen <> pretty x <> text ","

<> pretty y <> rparen) $ Map.assocs $ propMap m)

-- | Inclusion map of a subsig into a supersig

inclusionMap :: Sign.Sign -> Sign.Sign -> Morphism

inclusionMap s1 s2 = Morphism

{ source = s1

, target = s2

, propMap = Map.empty }

-- | creates a Morphism

mkMorphism :: Sign.Sign -> Sign.Sign -> Map.Map Id Id -> Morphism

mkMorphism s t p =

Morphism { source = s

, target = t

, propMap = p }

{- | sentence (text) translation along signature morphism

here just the renaming of formulae -}

mapSentence :: Morphism -> AS.TEXT_META -> Result.Result AS.TEXT_META

mapSentence mor tm =

return $ tm { getText = mapSen_txt mor $ getText tm }

-- propagates the translation to sentences

mapSen_txt :: Morphism -> AS.TEXT -> AS.TEXT

mapSen_txt mor txt = case txt of

AS.Text phrs r -> AS.Text (map (mapSen_phr mor) phrs) r

AS.Named_text n t r -> AS.Named_text n (mapSen_txt mor t) r

-- propagates the translation to sentences

mapSen_phr :: Morphism -> AS.PHRASE -> AS.PHRASE

mapSen_phr mor phr = case phr of

AS.Module m -> AS.Module $ mapSen_mod mor m

AS.Sentence s -> AS.Sentence $ mapSen_sen mor s

AS.Comment_text c t r -> AS.Comment_text c (mapSen_txt mor t) r

x -> x

-- propagates the translation to sentences

mapSen_mod :: Morphism -> AS.MODULE -> AS.MODULE

mapSen_mod mor m = case m of

AS.Mod n t rn -> AS.Mod n (mapSen_txt mor t) rn

AS.Mod_ex n exs t rn -> AS.Mod_ex n exs (mapSen_txt mor t) rn

mapSen_sen :: Morphism -> AS.SENTENCE -> AS.SENTENCE

mapSen_sen mor frm = case frm of

AS.Quant_sent q vs is rn ->

AS.Quant_sent q (map (mapSen_nos mor) vs) (mapSen_sen mor is) rn

AS.Bool_sent bs rn -> AS.Bool_sent (case bs of

AS.Junction j sens -> AS.Junction j (map (mapSen_sen mor) sens)

AS.Negation sen -> AS.Negation (mapSen_sen mor sen)

AS.BinOp op s1 s2 ->

AS.BinOp op (mapSen_sen mor s1) (mapSen_sen mor s2)

) rn

AS.Atom_sent atom rn -> AS.Atom_sent (case atom of

AS.Equation t1 t2 -> AS.Equation (mapSen_trm mor t1) (mapSen_trm mor t2)

AS.Atom t tss -> AS.Atom (mapSen_trm mor t) (map (mapSen_trmSeq mor) tss)

) rn

AS.Comment_sent cm sen rn -> AS.Comment_sent cm (mapSen_sen mor sen) rn

AS.Irregular_sent sen rn -> AS.Irregular_sent (mapSen_sen mor sen) rn

mapSen_trm :: Morphism -> AS.TERM -> AS.TERM

mapSen_trm mor trm = case trm of

AS.Name_term n -> AS.Name_term (mapSen_tok mor n)

AS.Funct_term t ts rn ->

AS.Funct_term (mapSen_trm mor t) (map (mapSen_trmSeq mor) ts) rn

AS.Comment_term t c rn -> AS.Comment_term (mapSen_trm mor t) c rn

AS.That_term s rn -> AS.That_term (mapSen_sen mor s) rn

mapSen_nos :: Morphism -> AS.NAME_OR_SEQMARK -> AS.NAME_OR_SEQMARK

mapSen_nos mor nos = case nos of

AS.Name n -> AS.Name (mapSen_tok mor n)

AS.SeqMark s -> AS.SeqMark (mapSen_tok mor s)

mapSen_trmSeq :: Morphism -> AS.TERM_SEQ -> AS.TERM_SEQ

mapSen_trmSeq mor ts = case ts of

AS.Term_seq t -> AS.Term_seq (mapSen_trm mor t)

AS.Seq_marks s -> AS.Seq_marks (mapSen_tok mor s)

mapSen_tok :: Morphism -> Id.Token -> Id.Token

mapSen_tok mor tok = Id.idToSimpleId $ applyMorphism mor $ Id.simpleIdToId tok

-- | Union of two morphisms.

morphismUnion :: Morphism -> Morphism -> Result.Result Morphism

morphismUnion mor1 mor2 =

let pmap1 = propMap mor1

pmap2 = propMap mor2

p1 = source mor1

p2 = source mor2

up1 = Set.difference (allItems p1) $ Map.keysSet pmap1

up2 = Set.difference (allItems p2) $ Map.keysSet pmap2

(pds, pmap) = foldr ( \ (i, j) (ds, m) -> case Map.lookup i m of

Nothing -> (ds, Map.insert i j m)

Just k -> if j == k then (ds, m) else

(Diag Error

("incompatible mapping of prop " ++ showId i " to "

++ showId j " and " ++ showId k "")

nullRange : ds, m))

([], pmap1)

(Map.toList pmap2 ++ map (\ a -> (a, a))

(Set.toList $ Set.union up1 up2))

in if null pds then return Morphism

{ source = unite p1 p2

, target = unite (target mor1) $ target mor2

, propMap = pmap } else Result pds Nothing