1-- Copyright (C) 2006-2007 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; if not, write to the Free Software Foundation,
15-- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
16module Darcs.Repository.InternalTypes ( Repository, PristineType(..)
17                                      , repoCache, modifyCache
18                                      , repoFormat
19                                      , repoLocation
20                                      , withRepoLocation
21                                      , repoPristineType
22                                      , unsafeCoerceRepoType
23                                      , unsafeCoercePatchType
24                                      , unsafeCoerceR
25                                      , unsafeCoerceU
26                                      , unsafeCoerceT
27                                      , mkRepo
28                                      ) where
29
30import Darcs.Prelude
31
32import Darcs.Repository.Cache ( Cache )
33import Darcs.Repository.Format ( RepoFormat )
34import Darcs.Patch ( RepoType )
35import Darcs.Util.File ( withCurrentDirectory )
36import Unsafe.Coerce ( unsafeCoerce )
37
38data PristineType
39  = NoPristine
40  | PlainPristine
41  | HashedPristine
42    deriving ( Show, Eq )
43
44-- |A @Repository@ is a token representing the state of a repository on disk.
45-- It is parameterized by the patch type in the repository, and witnesses for
46-- the recorded state of the repository (i.e. what darcs get would retrieve),
47-- the unrecorded state (what's in the working tree now),
48-- and the tentative state, which represents work in progress that will
49-- eventually become the new recorded state unless something goes wrong.
50data Repository (rt :: RepoType) (p :: * -> * -> *) wRecordedstate wUnrecordedstate wTentativestate =
51  Repo !String !RepoFormat !PristineType Cache deriving ( Show )
52
53type role Repository nominal nominal nominal nominal nominal
54
55repoLocation :: Repository rt p wR wU wT -> String
56repoLocation (Repo loc _ _ _) = loc
57
58withRepoLocation :: Repository rt p wR wU wT -> IO a -> IO a
59withRepoLocation repo = withCurrentDirectory (repoLocation repo)
60
61repoFormat :: Repository rt p wR wU wT -> RepoFormat
62repoFormat (Repo _ fmt _ _) = fmt
63
64repoPristineType :: Repository rt p wR wU wT -> PristineType
65repoPristineType (Repo _ _ pr _) = pr
66
67repoCache :: Repository rt p wR wU wT -> Cache
68repoCache (Repo _ _ _ c) = c
69
70modifyCache :: (Cache -> Cache) -> Repository rt p wR wU wT -> Repository rt p wR wU wT
71modifyCache g (Repo l f p c) = Repo l f p (g c)
72
73unsafeCoerceRepoType :: Repository rt p wR wU wT -> Repository rt' p wR wU wT
74unsafeCoerceRepoType = unsafeCoerce
75
76unsafeCoercePatchType :: Repository rt p wR wU wT -> Repository rt p' wR wU wT
77unsafeCoercePatchType = unsafeCoerce
78
79unsafeCoerceR :: Repository rt p wR wU wT -> Repository rt p wR' wU wT
80unsafeCoerceR = unsafeCoerce
81
82unsafeCoerceU :: Repository rt p wR wU wT -> Repository rt p wR wU' wT
83unsafeCoerceU = unsafeCoerce
84
85unsafeCoerceT :: Repository rt p wR wU wT -> Repository rt p wR wU wT'
86unsafeCoerceT = unsafeCoerce
87
88mkRepo :: String -> RepoFormat -> PristineType -> Cache -> Repository rt p wR wU wT
89mkRepo = Repo
90