{-# LANGUAGE TypeSynonymInstances #-}

{- |

Module : $Id$

Description : CspCASL signatures

Copyright : (c) Markus Roggenbach and Till Mossakowski and Uni Bremen 2004

License : GPLv2 or higher, see LICENSE.txt

Maintainer : M.Roggenbach@swansea.ac.uk

Stability : provisional

Portability : portable

signatures for CSP-CASL

-}

module CspCASL.SignCSP where

import CspCASL.AS_CspCASL_Process (CHANNEL_NAME, PROCESS_NAME,

PROCESS (..), CommAlpha, CommType (..), TypedChanName (..))

import CspCASL.AS_CspCASL ()

import CspCASL.CspCASL_Keywords

import CspCASL.Print_CspCASL ()

import CASL.AS_Basic_CASL (CASLFORMULA, SORT, TERM)

import CASL.Sign (CASLSign, emptySign, Sign, extendedInfo, sortRel)

import Common.AS_Annotation (Named)

import Common.Doc

import Common.DocUtils

import Common.Id

import Common.Lib.Rel (predecessors)

import qualified Data.Map as Map

import qualified Data.Set as Set

-- | A process has zero or more parameter sorts, and a communication

-- alphabet.

data ProcProfile = ProcProfile [SORT] CommAlpha

deriving (Eq, Ord, Show)

type ChanNameMap = Map.Map CHANNEL_NAME SORT

type ProcNameMap = Map.Map PROCESS_NAME ProcProfile

type ProcVarMap = Map.Map SIMPLE_ID SORT

type ProcVarList = [(SIMPLE_ID, SORT)]

-- Close a communication alphabet under CASL subsort

closeCspCommAlpha :: CspCASLSign -> CommAlpha -> CommAlpha

closeCspCommAlpha sig =

Set.unions . Set.toList . Set.map (closeOneCspComm sig)

-- Close one CommType under CASL subsort

closeOneCspComm :: CspCASLSign -> CommType -> CommAlpha

closeOneCspComm sig x = let

mkTypedChan c s = CommTypeChan $ TypedChanName c s

subsorts s' =

Set.singleton s' `Set.union` predecessors (sortRel sig) s'

in case x of

CommTypeSort s ->

Set.map CommTypeSort (subsorts s)

CommTypeChan (TypedChanName c s) ->

Set.map CommTypeSort (subsorts s)

`Set.union` Set.map (mkTypedChan c) (subsorts s)

{- Will probably be useful, but doesn't appear to be right now.

-- Extract the sorts from a process alphabet

procAlphaSorts :: CommAlpha -> Set.Set SORT

procAlphaSorts a = stripMaybe $ Set.map justSort a

where justSort n = case n of

(CommTypeSort s) -> Just s

_ -> Nothing

-- Extract the typed channel names from a process alphabet

procAlphaChans :: CommAlpha -> Set.Set TypedChanName

procAlphaChans a = stripMaybe $ Set.map justChan a

where justChan n = case n of

(CommTypeChan c) -> Just c

_ -> Nothing

-- Given a set of Maybes, filter to keep only the Justs

stripMaybe :: Ord a => Set.Set (Maybe a) -> Set.Set a

stripMaybe x = Set.fromList $ Maybe.catMaybes $ Set.toList x

-- Close a set of sorts under a subsort relation

cspSubsortCloseSorts :: CspCASLSign -> Set.Set SORT -> Set.Set SORT

cspSubsortCloseSorts sig sorts =

Set.unions subsort_sets

where subsort_sets =

Set.toList $ Set.map (cspSubsortPreds sig) sorts

-}

-- | CSP process signature.

data CspSign = CspSign

{ chans :: ChanNameMap

, procSet :: ProcNameMap

-- | Added for uniformity to the CASL static analysis. After

-- static analysis this is the empty list.

, ccSentences :: [Named CspCASLSen]

} deriving (Eq, Ord, Show)

-- | I dont know if this is implemented correctly. Always prefers sign1 if there

-- are clashes in chans or procSet. BUG?

cspSignUnion :: CspSign -> CspSign -> CspSign

cspSignUnion sign1 sign2 =

CspSign { chans = Map.union (chans sign1) (chans sign2)

, procSet = Map.union (procSet sign1) (procSet sign2)

, ccSentences = ccSentences sign1 ++ ccSentences sign2

}

-- | A CspCASL signature is a CASL signature with a CSP process

-- signature in the extendedInfo part.

type CspCASLSign = Sign () CspSign

ccSig2CASLSign :: CspCASLSign -> CASLSign

ccSig2CASLSign sigma = sigma { extendedInfo = () }

-- | Projection from CspCASL signature to Csp signature

ccSig2CspSign :: CspCASLSign -> CspSign

ccSig2CspSign = extendedInfo

-- | Empty CspCASL signature.

emptyCspCASLSign :: CspCASLSign

emptyCspCASLSign = emptySign emptyCspSign

-- | Empty CSP process signature.

emptyCspSign :: CspSign

emptyCspSign = CspSign

{ chans = Map.empty

, procSet = Map.empty

, ccSentences = []

}

-- | Compute union of two CSP process signatures.

addCspProcSig :: CspSign -> CspSign -> CspSign

addCspProcSig a b = emptyCspSign

{ chans = chans a `Map.union` chans b

, procSet = procSet a `Map.union` procSet b

}

-- | Compute difference of two CSP process signatures.

diffCspProcSig :: CspSign -> CspSign -> CspSign

diffCspProcSig a b = emptyCspSign

{ chans = chans a `Map.difference` chans b

, procSet = procSet a `Map.difference` procSet b

}

-- | Is one Csp Signature a sub signature of another

isCspSubSign :: CspSign -> CspSign -> Bool

isCspSubSign a b =

chans a `Map.isSubmapOf` chans b &&

procSet a `Map.isSubmapOf` procSet b

-- | Pretty printing for CspCASL signatures

instance Pretty CspSign where

pretty = printCspSign

printCspSign :: CspSign -> Doc

printCspSign sigma =

chan_part $+$ proc_part

where chan_part =

case Map.size $ chans sigma of

0 -> empty

s -> keyword (if s > 1 then channelsS else channelS)

<+> printChanNameMap (chans sigma)

proc_part = keyword processS <+>

printProcNameMap (procSet sigma)

-- | Pretty printing for channel name maps

instance Pretty ChanNameMap where

pretty = printChanNameMap

printChanNameMap :: ChanNameMap -> Doc

printChanNameMap chanMap =

vcat $ punctuate semi $ map printChan $ Map.toList chanMap

where printChan (chanName, sort) =

pretty chanName <+> colon <+> pretty sort

-- | Pretty printing for process name maps

instance Pretty ProcNameMap where

pretty = printProcNameMap

printProcNameMap :: ProcNameMap -> Doc

printProcNameMap procNameMap =

vcat $ punctuate semi $ map printProcName $ Map.toList procNameMap

where printProcName (procName, procProfile) =

pretty procName <+> pretty procProfile

-- | Pretty printing for process profiles

instance Pretty ProcProfile where

pretty = printProcProfile

printProcProfile :: ProcProfile -> Doc

printProcProfile (ProcProfile sorts commAlpha) =

printArgs sorts <+> colon <+> ppWithCommas (Set.toList commAlpha)

where printArgs [] = empty

printArgs args = parens $ ppWithCommas args

-- Sentences

-- | FQProcVarList should only contain fully qualified CASL variables which are

-- | TERMs i.e. constructed via the TERM constructor Qual_var.

type FQProcVarList = [TERM ()]

-- | A CspCASl senetence is either a CASL formula or a Procsses equation. A

-- | process equation has on the LHS a process name, a list of parameters which

-- | are qualified variables (which are terms), a constituent( or is it

-- | permitted ?) communication alphabet and finally on the RHS a fully

-- | qualified process.

data CspCASLSen

= CASLSen (CASLFORMULA)

| ProcessEq PROCESS_NAME FQProcVarList CommAlpha PROCESS

deriving (Show, Eq, Ord)

instance GetRange CspCASLSen

instance Pretty CspCASLSen where

pretty (CASLSen f) = pretty f

pretty (ProcessEq pn varList _commAlpha proc) =

let varDoc = if null varList

then empty

else parens $ ppWithCommas varList

in pretty pn <+> varDoc <+> equals <+> pretty proc

-- | Empty CspCASL sentence

emptyCCSen :: CspCASLSen

emptyCCSen =

let emptyProcName = mkSimpleId "empty"

emptyVarList = []

emptyAlphabet = Set.empty

emptyProc = Skip nullRange

-- BUG - this is incorrect

in ProcessEq emptyProcName emptyVarList emptyAlphabet emptyProc

-- | Test if a CspCASL sentence is a CASL sentence

isCASLSen :: CspCASLSen -> Bool

isCASLSen (CASLSen _) = True

isCASLSen _ = False

-- | Test if a CspCASL sentence is a Process Equation.

isProcessEq :: CspCASLSen -> Bool

isProcessEq (ProcessEq _ _ _ _) = True

isProcessEq _ = False