Hdoc/TCT/Read.hs

   1 module Hdoc.TCT.Read
   2  ( module Hdoc.TCT.Read.Cell
   3  , module Hdoc.TCT.Read.Elem
   4  , module Hdoc.TCT.Read.Token
   5  , module Hdoc.TCT.Read.Tree
   6  , module Hdoc.TCT.Read
   7  ) where
   8
   9 import Control.Applicative (Applicative(..))
  10 import Control.Arrow (left)
  11 import Control.Monad (Monad(..), join, (=<<))
  12 import Data.Bool
  13 import Data.Either (Either(..))
  14 import Data.Eq (Eq(..))
  15 import Data.Foldable (Foldable(..), any)
  16 import Data.Function (($), (.))
  17 import Data.Functor ((<$>))
  18 import Data.Functor.Compose (Compose(..))
  19 import Data.List.NonEmpty (NonEmpty(..))
  20 import Data.Semigroup (Semigroup(..))
  21 import Data.Traversable (Traversable(..))
  22 import Data.TreeSeq.Strict (Tree(..), Trees)
  23 import Data.Void (Void)
  24 import System.FilePath ((</>), takeDirectory)
  25 import System.IO (FilePath, IO)
  26 import Text.Show (Show(..), showString)
  27 import qualified Control.Monad.Trans.Reader as R
  28 import qualified Data.ByteString.Lazy as BSL
  29 import qualified Data.Text.Lazy as TL
  30 import qualified Data.Text.Lazy.Encoding as TL
  31 import qualified System.Directory as Directory
  32 import qualified System.FilePath as FilePath
  33 import qualified System.IO.Error as IO
  34 import qualified Text.Megaparsec as P
  35
  36 import Hdoc.TCT.Debug
  37 import Hdoc.TCT.Tree
  38 import Hdoc.TCT.Cell
  39 import Hdoc.TCT.Read.Cell
  40 import Hdoc.TCT.Read.Elem
  41 import Hdoc.TCT.Read.Tree
  42 import Hdoc.TCT.Read.Token
  43
  44 -- | Parsing is done in two phases:
  45 --
  46 -- 1. Indentation-sensitive parsing on 'TL.Text'.
  47 -- 2. 'Pair'-sensitive parsing on some 'NodeText's resulting of 1. .
  48 readTCT :: FilePath -> IO (Either ErrorRead (Trees (Cell Node)))
  49 readTCT inp = do
  50         inpFileCanon <-
  51                 Directory.makeRelativeToCurrentDirectory =<<
  52                 Directory.canonicalizePath inp
  53         goFile (NodeHeader HeaderDash) $
  54                 Span inpFileCanon pos1 pos1:|[]
  55         where
  56         goFile :: Node -> NonEmpty Span -> IO (Either ErrorRead (Trees (Cell Node)))
  57         goFile parentNode loc@(Span{span_file=inpFile}:|inpPath)
  58          | any (\Span{span_file} -> span_file == inpFile) inpPath =
  59                 return $ Left $ ErrorReadIncludeLoop loc
  60          | otherwise = do
  61                 readFile inpFile >>= \case
  62                  Left err -> return $ Left $ ErrorReadIO loc err
  63                  Right inpText ->
  64                         case (`R.runReader` inpPath) $ P.runParserT (p_Trees <* P.eof) inpFile inpText of
  65                          Left err -> return $ Left $ ErrorReadParser err
  66                          Right trees ->
  67                                 (join <$>) . sequence <$>
  68                                 traverse
  69                                  (goTree parentNode)
  70                                  trees
  71                                  -- DEBUG: (debug0 "readTCT" trees)
  72         goTree :: Node -> Tree (Cell Node) -> IO (Either ErrorRead (Trees (Cell Node)))
  73         goTree parNode t@(Tree c@(Cell ss@(Span{span_file}:|_sn) nod) ts) =
  74                 case nod of
  75                  NodeLower{} -> return $ Right $ pure t
  76                  -- NOTE: preserve NodeText ""
  77                  NodeText n | TL.null n -> return $ Right $ pure t
  78                  NodeText n ->
  79                         case parNode of
  80                          NodeHeader HeaderBar{}      -> return $ Right $ pure t
  81                          NodeHeader HeaderEqual{}    -> return $ Right $ pure t
  82                          NodeHeader HeaderDashDash{} -> return $ Right $ pure t
  83                          _ ->
  84                                 return $ left ErrorReadParser $
  85                                 parseTokens <$> parseLexemes (Cell ss n)
  86                  NodeHeader (HeaderDotSlash incFile) -> do
  87                         incFileCanon <-
  88                                 Directory.makeRelativeToCurrentDirectory =<<
  89                                 Directory.canonicalizePath
  90                                  (FilePath.takeDirectory span_file </> incFile)
  91                         ((pure . Tree c <$>) <$>) $
  92                          -- NOTE: preserve HeaderDotSlash to avoid Seq.spanl
  93                          --       to merge nodes accross files, when writing XML
  94                                 goFile parNode $ Span incFileCanon pos1 pos1 :| toList ss
  95                  _ ->
  96                         (pure . Tree c . join <$>) .
  97                         sequence <$> traverse (goTree nod') ts
  98                         where
  99                         -- NOTE: skip parent 'Node's whose semantic does not change 'NodeText'
 100                         nod' = case nod of
 101                          NodePara -> parNode
 102                          _ -> nod
 103
 104 readFile :: FilePath -> IO (Either IO.IOError TL.Text)
 105 readFile fp =
 106         (Right . TL.decodeUtf8 <$> BSL.readFile fp)
 107         `IO.catchIOError` \e ->
 108                 if IO.isAlreadyInUseError e
 109                 || IO.isDoesNotExistError e
 110                 || IO.isPermissionError   e
 111                 then return $ Left e
 112                 else IO.ioError e
 113
 114 -- | Useful when producing only an exact source file rendition.
 115 readTCTWithoutIncludes ::
 116  FilePath -> TL.Text ->
 117  Either ErrorRead (Trees (Cell Node))
 118 readTCTWithoutIncludes inp txt = do
 119         trees <-
 120                 left ErrorReadParser $
 121                 (`R.runReader` []) $
 122                 P.runParserT (p_Trees <* P.eof) inp txt
 123         join <$> traverse (go $ NodeHeader HeaderDash) trees
 124          -- (debug0 "readTCTWithoutIncludes" trees)
 125         where
 126         go :: Node -> Tree (Cell Node) -> Either ErrorRead (Trees (Cell Node))
 127         go parent t@(Tree c@(Cell ssn nod) ts) =
 128                 case nod of
 129                  NodeLower{} -> Right $ pure t
 130                  -- NOTE: preserve NodeText ""
 131                  NodeText n | TL.null n -> Right $ pure t
 132                  NodeText n ->
 133                         case parent of
 134                          NodeHeader HeaderBar{}      -> Right $ pure t
 135                          NodeHeader HeaderEqual{}    -> Right $ pure t
 136                          NodeHeader HeaderDashDash{} -> Right $ pure t
 137                          _ -> left ErrorReadParser $ parseTokens <$> parseLexemes (Cell ssn n)
 138                  _ -> pure . Tree c . join <$> traverse (go nod') ts
 139                         where
 140                         -- NOTE: skip parent 'Node's whose semantic does not change 'NodeText'
 141                         nod' = case nod of
 142                          NodePara -> parent
 143                          _ -> nod
 144
 145 dependencies :: Trees (Cell Node) -> [FilePath]
 146 dependencies = foldr (go "") []
 147         where
 148         go :: FilePath -> Tree (Cell Node) -> [FilePath] -> [FilePath]
 149         go dir (Tree (Cell _ss n) ts) acc =
 150                 case n of
 151                  NodeHeader (HeaderDotSlash file) ->
 152                         (dir</>file) :
 153                         foldr (go (dir</>takeDirectory file)) acc ts
 154                  _ ->
 155                         foldr (go dir) acc ts
 156
 157 -- * Type 'ErrorRead'
 158 data ErrorRead
 159  =   ErrorReadParser (P.ParseError (P.Token TL.Text) (P.ErrorFancy Void))
 160  |   ErrorReadIncludeLoop Location
 161  |   ErrorReadIO Location IO.IOError
 162  deriving (Eq)
 163 instance Show ErrorRead where
 164         showsPrec _p = \case
 165          ErrorReadParser e ->
 166                 showString (P.parseErrorPretty e)
 167          ErrorReadIncludeLoop (Span{..}:|loc) ->
 168                 showString "ErrorReadIncludeLoop" .
 169                 showString "\n             " . showString span_file .
 170                 showString (foldMap (\s -> "\n included by "<>show s) loc)
 171          ErrorReadIO (_:|loc) err ->
 172                 showString "ErrorReadIO" .
 173                 showString "\n " . showsPrec 10 err .
 174                 showString (foldMap (\s -> "\n in "<>show s) loc)