src/Darcs/PopulationData.hs

   1 --   Copyright (C) 2003-2004 Jan Scheffczyk and David Roundy
   2 --
   3 --   This program is free software; you can redistribute it and/or modify
   4 --   it under the terms of the GNU General Public License as published by
   5 --   the Free Software Foundation; either version 2, or (at your option)
   6 --   any later version.
   7 --
   8 --   This program is distributed in the hope that it will be useful,
   9 --   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 --   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 --   GNU General Public License for more details.
  12 --
  13 --   You should have received a copy of the GNU General Public License
  14 --   along with this program; see the file COPYING.  If not, write to
  15 --   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16 --   Boston, MA 02110-1301, USA.
  17
  18 module Darcs.PopulationData ( Population(..), PopTree(..), Info(..),
  19                         setPopState, notModified, setState,
  20                         DirMark(..), getPopFrom
  21                       ) where
  22 import Darcs.Patch.Info
  23 import Darcs.Utils ( withCurrentDirectory )
  24 import System.Directory ( doesDirectoryExist, getDirectoryContents )
  25 import qualified Data.ByteString.Char8 as BC
  26 import qualified Data.ByteString       as B (ByteString)
  27
  28 -- | the population of a darcs repository (simpler Slurpy)
  29 data Population = Pop { popState :: PatchInfo -- ^ the state when last modified
  30                       , popTree  :: PopTree   -- ^ the directory listing
  31                       }
  32  deriving (Show, Eq)
  33
  34 setPopState :: PatchInfo -> Population -> Population
  35 setPopState i (Pop _ tr) = Pop i tr
  36
  37 -- | directory listing
  38 data PopTree = PopDir !Info ![PopTree]
  39              | PopFile !Info
  40  deriving ( Ord, Eq )
  41
  42 -- | info of a directory member
  43 data DirMark = AddedFile | RemovedFile | MovedFile String
  44              | ModifiedFile | DullFile
  45              | AddedDir | RemovedDir | MovedDir !String | DullDir
  46                deriving ( Ord, Eq )
  47 data Info = Info {nameI :: !B.ByteString, -- ^ name of the element
  48                   modifiedByI :: !PatchInfo, -- ^ last patch modifying this element
  49                   modifiedHowI :: !DirMark, -- ^ how was it modified
  50                   createdByI :: !(Maybe PatchInfo), -- ^ this can be unknown when restored backwards!
  51                   creationNameI :: !(Maybe B.ByteString) -- ^ the original name of the element
  52                  }
  53  deriving ( Ord, Eq )
  54
  55 -- | was an Info record not modified?
  56 notModified :: Info -> Bool
  57 notModified i = (modifiedHowI i == DullFile) || (modifiedHowI i == DullDir)
  58
  59 -- | set the modifier for an Info record
  60 setState :: Info -> PatchInfo -> Info
  61 setState i pinfo = i { modifiedByI = pinfo }
  62
  63 instance Show PopTree where
  64  show s = showPop "" s
  65
  66 showPop :: String -> PopTree -> String
  67 showPop indent (PopDir i fs)
  68  = indent ++ show i ++ "\n" ++
  69    unlines (map (showPop (' ':indent)) fs)
  70 showPop indent (PopFile i)
  71  = indent ++ show i
  72
  73 instance Show Info where
  74  show i = show (nameI i) ++ " " ++ show (modifiedHowI i) ++
  75           " at state " ++ show (modifiedByI i)
  76
  77 instance Show DirMark where
  78  show AddedFile = "File added"
  79  show RemovedFile = "File removed"
  80  show (MovedFile s) = "File moved to " ++ s
  81  show ModifiedFile = "File modified"
  82  show DullFile = "File old"
  83  show AddedDir = "Dir added"
  84  show RemovedDir = "Dir removed"
  85  show (MovedDir s) = "Dir moved from " ++ s
  86  show DullDir = "Dir old"
  87
  88 -- | read the population from a given directory @dirname@
  89 --   all folders and documents get the given time @t@
  90 --
  91 --  This needs to be here in order to avoid a circular dependency
  92 --  between Population and Pristine.
  93 getPopFrom :: FilePath -> PatchInfo -> IO Population
  94 getPopFrom the_directory pinfo =
  95     withCurrentDirectory the_directory $
  96        do popT <- getPopFrom_helper "."
  97           return (Pop pinfo popT)
  98  where getPopFrom_helper :: FilePath -> IO PopTree
  99        getPopFrom_helper dirname = do
 100         isdir <- doesDirectoryExist dirname
 101         let n = BC.pack dirname
 102         if isdir
 103           then do
 104            fnames <- getDirectoryContents dirname
 105            sl <- withCurrentDirectory dirname
 106                  (sequence $ map getPopFrom_helper $ filter not_hidden fnames)
 107            let i = Info {nameI = n,
 108                          modifiedByI = pinfo,
 109                          modifiedHowI = DullDir,
 110                          createdByI = Just pinfo,
 111                          creationNameI = Just n}
 112            return $ PopDir i sl
 113           else do let i = Info {nameI = n,
 114                                 modifiedByI = pinfo,
 115                                 modifiedHowI = DullFile,
 116                                 createdByI = Just pinfo,
 117                                 creationNameI = Just n}
 118                   return $ PopFile i
 119
 120 not_hidden :: FilePath -> Bool
 121 not_hidden ('.':_) = False
 122 not_hidden ('_':_) = False
 123 not_hidden _ = True