module Darcs.Email ( make_email, read_email ) where
import Data.Char ( digitToInt, isHexDigit )
import Printer ( Doc, ($$), (<+>), (<>), text, empty, packedString, renderPS)
import ByteStringUtils (dropSpace, linesPS, betweenLinesPS )
import qualified Data.ByteString as B (ByteString, length, null, tail, drop, head)
import qualified Data.ByteString.Char8 as BC (index, head, pack)
#if __GLASGOW_HASKELL__ > 606
import Data.ByteString.Internal as B (c2w, createAndTrim)
#else
import Data.ByteString.Base as B (c2w, createAndTrim)
#endif
import System.IO.Unsafe ( unsafePerformIO )
import Foreign.Ptr ( Ptr, plusPtr )
import Foreign.Storable ( poke )
import Data.Word ( Word8 )
line_max :: Int
line_max = 75
qpencode :: B.ByteString -> B.ByteString
qpencode s = unsafePerformIO
$ B.createAndTrim (4 * B.length s) (\buf -> encode s line_max buf 0)
encode :: B.ByteString -> Int -> Ptr Word8 -> Int -> IO Int
encode ps _ _ bufi | B.null ps = return bufi
encode ps n buf bufi = case B.head ps of
c | c == newline ->
do poke (buf `plusPtr` bufi) newline
encode ps' line_max buf (bufi+1)
| n == 0 && B.length ps > 1 ->
do poke (buf `plusPtr` bufi) equals
poke (buf `plusPtr` (bufi+1)) newline
encode ps line_max buf (bufi + 2)
| (c == tab || c == space) ->
if B.null ps' || B.head ps' == newline
then do poke (buf `plusPtr` bufi) c
poke (buf `plusPtr` (bufi+1)) equals
poke (buf `plusPtr` (bufi+2)) newline
encode ps' line_max buf (bufi + 3)
else do poke (buf `plusPtr` bufi) c
encode ps' (n 1) buf (bufi + 1)
| (c >= bang && c /= equals && c <= tilde) ->
do poke (buf `plusPtr` bufi) c
encode ps' (n 1) buf (bufi + 1)
| n < 3 ->
encode ps 0 buf bufi
| otherwise ->
do let (x, y) = c `divMod` 16
h1 = intToUDigit x
h2 = intToUDigit y
poke (buf `plusPtr` bufi) equals
poke (buf `plusPtr` (bufi+1)) h1
poke (buf `plusPtr` (bufi+2)) h2
encode ps' (n 3) buf (bufi + 3)
where ps' = B.tail ps
newline = B.c2w '\n'
tab = B.c2w '\t'
space = B.c2w ' '
bang = B.c2w '!'
tilde = B.c2w '~'
equals = B.c2w '='
intToUDigit i
| i >= 0 && i <= 9 = B.c2w '0' + i
| i >= 10 && i <= 15 = B.c2w 'A' + i 10
| otherwise = error $ "intToUDigit: '"++show i++"'not a digit"
qpdecode :: B.ByteString -> B.ByteString
qpdecode s = unsafePerformIO
$ B.createAndTrim (B.length s + 1) (\buf -> decode (linesPS s) buf 0)
decode :: [B.ByteString] -> Ptr Word8 -> Int -> IO Int
decode [] _ bufi = return bufi
decode (ps:pss) buf bufi
| B.null (dropSpace ps)
= do poke (buf `plusPtr` bufi) newline
decode pss buf (bufi+1)
| is_equals && B.length ps >= 3 && isHexDigit c1 && isHexDigit c2
= do poke (buf `plusPtr` bufi)
(toWord8 $ digitToInt c1 * 16 + digitToInt c2)
decode (B.drop 3 ps:pss) buf (bufi+1)
| is_equals && B.null (dropSpace (B.tail ps)) = decode pss buf bufi
| otherwise = do poke (buf `plusPtr` bufi) (B.head ps)
decode (B.tail ps:pss) buf (bufi+1)
where is_equals = BC.head ps == '='
c1 = BC.index ps 1
c2 = BC.index ps 2
newline = B.c2w '\n'
toWord8 :: Int -> Word8
toWord8 = fromIntegral
make_email :: String -> [(String, String)] -> (Maybe Doc) -> Doc -> (Maybe String) -> Doc
make_email repodir headers mcontents bundle mfilename =
text "DarcsURL:" <+> text repodir
$$ foldl (\m (h,v) -> m $$ (text (h ++ ":") <+> text v)) empty headers
$$ text "MIME-Version: 1.0"
$$ text "Content-Type: multipart/mixed; boundary=\"=_\""
$$ text ""
$$ text "--=_"
$$ (case mcontents of
Just contents ->
text "Content-Type: text/plain"
$$ text "Content-Transfer-Encoding: quoted-printable"
$$ text ""
$$ packedString (qpencode (renderPS contents))
$$ text ""
$$ text "--=_"
Nothing -> empty)
$$ text "Content-Type: text/x-darcs-patch" <>
(case mfilename of
Just filename -> text "; name=\"" <> text filename <> text "\""
Nothing -> empty)
$$ text "Content-Transfer-Encoding: quoted-printable"
$$ text "Content-Description: A darcs patch for your repository!"
$$ text ""
$$ packedString (qpencode (renderPS bundle))
$$ text "--=_--"
$$ text ""
$$ text "."
$$ text ""
$$ text ""
read_email :: B.ByteString -> B.ByteString
read_email s =
case betweenLinesPS
(BC.pack "Content-Description: A darcs patch for your repository!")
(BC.pack "--=_--") s of
Nothing -> s
Just s' -> qpdecode s'