{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE RankNTypes #-}

module Traverse where

import Analysis.Annotations
import Language.Fortran

import Generics.Deriving.Base
import Generics.Deriving.Copoint
import GHC.Generics

import Control.Monad.Trans.Writer.Lazy

import Data.Generics.Zipper
import Data.Generics.Aliases
import Data.Generics.Str
import Data.Generics.Uniplate.Operations

import Language.Fortran.Lexer

import Control.Comonad

import Data.Data
import Data.Maybe
import Data.Monoid     

import Debug.Trace

instance Monoid x => Monad ((,) x) where
    return a = (mempty, a)
    (x, a) >>= k = let (x', b) = k a
                   in (mappend x x', b)



-- Data-type generic comonad-style traversal

extendBi :: (Biplate (from a) (to a), RComonad to) => (to a -> a) -> (from a) -> (from a)
extendBi f x = case biplate x of
                     (current, generate) -> generate $ strMap (rextend f) current

reduceCollect :: (Data s, Data t, Uniplate t, Biplate t s) => (s -> Maybe a) -> t -> [a]
reduceCollect k x = execWriter (transformBiM (\y -> do case k y of 
                                                         Just x -> tell [x]
                                                         Nothing -> return ()
                                                       return y) x) 

-- Data-type generic comonad-style traversal with zipper (contextual traversal)
                         
everywhere :: (Zipper a -> Zipper a) -> Zipper a -> Zipper a
everywhere k z = let everywhere' = enterRight . enterDown . k
           
                     enterDown z = case (down' z) of
                                     Just dz -> let dz' = everywhere' dz
                                                in case (up $ dz') of
                                                     Just uz -> uz
                                                     Nothing -> dz'
                                     Nothing -> z

                     enterRight z = case (right z) of
                                      Just rz -> let rz' = everywhere' rz
                                                 in case (left $ rz') of
                                                     Just lz -> lz 
                                                     Nothing -> rz'
                                      Nothing -> z
                  in everywhere' z
                              

zfmap :: Data a => (a -> a) -> Zipper (d a) -> Zipper (d a)
zfmap f x = zeverywhere (mkT f) x

-- This one is less useful as the definitions for comonads are then very annoying

extendBi' :: (Biplate (from a) (to a), Comonad to) => (to a -> a) -> (from a) -> (from a)
extendBi' f x = case biplate x of
                     (current, generate) -> generate $ strMap (extend f) current

class RComonad t where
    rextract :: t a -> a
    rextend :: (t a -> a) -> t a -> t a

class RFunctor t where
    rfmap :: (a -> a) -> t a -> t a
     

instance RComonad Fortran where
    rextract x = tag x

    rextend k y@(Assg _ sp e1 e2)        = Assg (k y) sp e1 e2
    rextend k y@(For _ sp v e1 e2 e3 fs) = For (k y) sp v e1 e2 e3 (rextend k fs)
    rextend k y@(FSeq _ sp f1 f2)        = FSeq (k y) sp (rextend k f1) (rextend k f2)
    rextend k y@(If _ sp e f1 fes f3)    = let fes' = map (\(e, f) -> (e, rextend k f)) fes
                                               f3' = case f3 of 
                                                    Nothing -> Nothing
                                                    Just f3a -> Just (rextend k f3a)
                                            in If (k y) sp e (rextend k f1) fes' f3'
    rextend k y@(Allocate _ sp e1 e2)      = Allocate (k y) sp e1 e2
    rextend k y@(Backspace _ sp sp')        = Backspace (k y) sp sp'
    rextend k y@(Call _ sp e as)           = Call (k y) sp e as
    rextend k y@(Open _ sp s)              = Open (k y) sp s
    rextend k y@(Close _ sp s)             = Close (k y) sp s
    rextend k y@(Continue _ sp)            = Continue (k y) sp
    rextend k y@(Cycle _ sp s)             = Cycle (k y) sp s
    rextend k y@(Deallocate _ sp es e)     = Deallocate (k y) sp es e
    rextend k y@(Endfile _ sp s)           = Endfile (k y) sp s
    rextend k y@(Exit _ sp s)              = Exit (k y) sp s
    rextend k y@(Forall _ sp es f)         = Forall (k y) sp es (rextend k f)
    rextend k y@(Goto _ sp s)              = Goto (k y) sp s
    rextend k y@(Nullify _ sp e)           = Nullify (k y) sp e
    rextend k y@(Inquire _ sp s e)         = Inquire (k y) sp s e
    rextend k y@(Rewind _ sp s)            = Rewind (k y) sp s
    rextend k y@(Stop _ sp e)              = Stop (k y) sp e
    rextend k y@(Where _ sp e f Nothing)   = Where (k y) sp e (rextend k f) Nothing
    rextend k y@(Where _ sp e f (Just f')) = Where (k y) sp e (rextend k f) (Just (rextend k f'))
    rextend k y@(Write _ sp s e)           = Write (k y) sp s e
    rextend k y@(PointerAssg _ sp e1 e2)   = PointerAssg (k y) sp e1 e2
    rextend k y@(Return _ sp e)            = Return (k y) sp e
    rextend k y@(Label _ sp s f)           = Label (k y) sp s (rextend k f)
    rextend k y@(Print _ sp e es)          = Print (k y) sp e es
    rextend k y@(ReadS _ sp s e)           = ReadS (k y) sp s e
    rextend k y@(TextStmt _ sp s)          = TextStmt (k y) sp s
    rextend k y@(NullStmt _ sp)            = NullStmt (k y) sp

class Refill d where
    refill :: d a -> a -> d a

instance Refill Fortran where
    refill y@(Assg _ sp e1 e2)         a = Assg a sp e1 e2
    refill y@(For _ sp v e1 e2 e3 fs)  a = For a sp v e1 e2 e3 fs
    refill y@(DoWhile _ sp e f)        a = DoWhile a sp e f
    refill y@(FSeq _ sp f1 f2)         a = FSeq a sp f1 f2
    refill y@(If _ sp e f1 fes f3)     a = If a sp e f1 fes f3
    refill y@(Allocate _ sp e1 e2)     a = Allocate a sp e1 e2
    refill y@(Backspace _ sp sp')      a = Backspace a sp sp'
    refill y@(Call _ sp e as)          a = Call a sp e as
    refill y@(Open _ sp s)             a = Open a sp s
    refill y@(Close _ sp s)            a = Close a sp s
    refill y@(Continue _ sp)           a = Continue a sp
    refill y@(Cycle _ sp s)            a = Cycle a sp s
    refill y@(DataStmt _ sp p)         a = DataStmt a sp p
    refill y@(Deallocate _ sp es e)    a = Deallocate a sp es e
    refill y@(Endfile _ sp s)          a = Endfile a sp s
    refill y@(Exit _ sp s)             a = Exit a sp s
    refill y@(Forall _ sp es f)        a = Forall a sp es f
    refill y@(Format _ sp s)           a = Format a sp s
    refill y@(Goto _ sp s)             a = Goto a sp s
    refill y@(Nullify _ sp e)          a = Nullify a sp e
    refill y@(Inquire _ sp s e)        a = Inquire a sp s e
    refill y@(Pause _ sp s)            a = Pause a sp s
    refill y@(Rewind _ sp s)           a = Rewind a sp s
    refill y@(Stop _ sp e)             a = Stop a sp e
    refill y@(Where _ sp e f f')       a = Where a sp e f f'
    refill y@(Write _ sp s e)          a = Write a sp s e
    refill y@(PointerAssg _ sp e1 e2)  a = PointerAssg a sp e1 e2
    refill y@(Return _ sp e)           a = Return a sp e
    refill y@(Label _ sp s f)          a = Label a sp s f
    refill y@(Print _ sp e es)         a = Print a sp e es
    refill y@(ReadS _ sp s e)          a = ReadS a sp s e
    refill y@(TextStmt _ sp s)         a = TextStmt a sp s
    refill y@(NullStmt _ sp)           a = NullStmt a sp


-- > instance Comonad Fortran where
-- >     extract x = rextract x

-- >     extend k y@(Assg _ sp e1 e2)        = Assg (k y) sp  (fmap (k . NullStmt) e1) 
-- >                                                     (fmap (k . NullStmt) e2)

-- >     extend k y@(For _ sp v e1 e2 e3 fs) = For (k y) sp  (fmap (k . NullStmt) v)
-- >                                                   (fmap (k . NullStmt) e1)
-- >                                                    (fmap (k . NullStmt) e2)
-- >                                                     (fmap (k . NullStmt) e3)
-- >                                                      (extend k fs)

-- >     extend k y@(FSeq _ sp f1 f2)        = FSeq (k y) sp  (extend k f1) (extend k f2)
-- >     extend k y@(If _ sp e f1 fes f3)    = let fes' = map (\(e, f) -> (fmap (k . NullStmt) e, extend k f)) fes
-- >                                               f3' = case f3 of 
-- >                                                       Nothing -> Nothing
-- >                                                       Just f3a -> Just (extend k f3a)
-- >                                           in If (k y) sp  (fmap (k . NullStmt) e) (extend k f1) fes' f3'

-- >     extend k y@(Allocate _ sp e1 e2)      = Allocate (k y) sp  (fmap (k . NullStmt) e1)
-- >                                                           (fmap (k . NullStmt) e2)
-- >     extend k y@(Backspace _ sp sp')        = Backspace (k y) sp  (map (fmap (k . NullStmt)) sp')
-- >     extend k y@(Call _ sp e as)           = Call (k y) sp  (fmap (k . NullStmt) e)
-- >                                                       (fmap (k . NullStmt) as)
-- >     extend k y@(Open _ sp s)              = Open (k y) sp  (map (fmap (k . NullStmt)) s)
-- >     extend k y@(Close _ sp s)             = Close (k y) sp  (map (fmap (k . NullStmt)) s)
-- >     extend k y@(Continue _ sp)            = Continue (k y) sp 
-- >     extend k y@(Cycle _ sp s)             = Cycle (k y) sp  s
-- >     extend k y@(Deallocate _ sp es e)     = Deallocate (k y) sp  (map (fmap (k . NullStmt)) es) (fmap (k . NullStmt) e)
-- >     extend k y@(Endfile _ sp s)           = Endfile (k y) sp  (map (fmap (k . NullStmt)) s)
-- >     extend k y@(Exit _ sp s)              = Exit (k y) sp  s
-- >     extend k y@(Forall _ sp (es, e) f)    = let g (s, e1, e2, e3) = (s, fmap (k . NullStmt) e1, 
-- >                                                                        fmap (k . NullStmt) e2,
-- >                                                                          fmap (k . NullStmt) e3)
-- >                                             in Forall (k y) sp  (map g es, fmap (k . NullStmt) e) (extend k f)
-- >     extend k y@(Goto _ sp s)              = Goto (k y) sp  s
-- >     extend k y@(Nullify _ sp es)          = Nullify (k y) sp  (map (fmap (k . NullStmt)) es)
-- >     extend k y@(Inquire _ sp ss es)       = Inquire (k y) sp  (map (fmap (k . NullStmt)) ss) (map (fmap (k . NullStmt)) es)
-- >     extend k y@(Rewind _ sp ss)           = Rewind (k y) sp  (map (fmap (k . NullStmt)) ss)
-- >     extend k y@(Stop _ sp e)              = Stop (k y) sp  (fmap (k . NullStmt) e)
-- >     extend k y@(Where _ sp e f)           = Where (k y) sp  (fmap (k . NullStmt) e) (extend k f)
-- >     extend k y@(Write _ sp ss es)         = Write (k y) sp  (map (fmap (k . NullStmt)) ss) (map (fmap (k . NullStmt)) es)
-- >     extend k y@(PointerAssg _ sp e1 e2)   = PointerAssg (k y) sp  (fmap (k . NullStmt) e1) (fmap (k . NullStmt) e2)
-- >     extend k y@(Return _ sp e)            = Return (k y) sp  (fmap (k . NullStmt) e)
-- >     extend k y@(Label _ sp s f)           = Label (k y) sp  s (extend k f)
-- >     extend k y@(Print _ sp e es)          = Print (k y) sp  (fmap (k . NullStmt) e) (map (fmap (k . NullStmt)) es)
-- >     extend k y@(ReadS _ sp ss es)         = ReadS (k y) sp  (map (fmap (k . NullStmt)) ss) (map (fmap (k . NullStmt)) es)
-- >     extend k y@(TextStmt _ sp s)          = TextStmt (k y) sp  s
-- >     extend k y@(NullStmt _ sp)            = NullStmt (k y) sp 


annotation :: Tagged g => g a -> a
annotation = tag