3 import Prelude hiding (lookup)
5 import Bencode (BVal(..), InfoDict, encode)
6 import Crypto.Hash.SHA1 (hash)
7 import Data.ByteString.Char8 (ByteString, pack, unpack)
9 import Data.List (intercalate)
10 import Data.Map as M (Map, (!))
11 import Network.HTTP (simpleHTTP, getRequest, getResponseBody)
12 import Network.HTTP.Base (urlEncode)
14 import qualified Data.ByteString.Base16 as B16 (encode)
20 -- >>> urlEncodeHash $ pack "123456789abcdef123456789abcdef123456789a"
21 -- "%124Vx%9a%bc%de%f1%23Eg%89%ab%cd%ef%124Vx%9a"
22 urlEncodeHash :: ByteString -> String
23 urlEncodeHash bs = concatMap (encode' . unpack) (splitN 2 bs)
24 where encode' b@[c1, c2] = let c = chr (read ("0x" ++ b))
27 escape i c1 c2 | i `elem` nonSpecialChars = [i]
28 | otherwise = "%" ++ [c1] ++ [c2]
30 nonSpecialChars = ['A'..'Z'] ++ ['a'..'z'] ++ ['0'..'9'] ++ "-_.~"
32 infoHash :: Map BVal BVal -> ByteString
33 infoHash m = let info = m ! Bstr (pack "info")
34 in (hash . pack . encode) info
36 prepareRequest :: InfoDict -> String -> Integer -> String
37 prepareRequest d peer_id len =
38 let p = [("info_hash", urlEncodeHash ((B16.encode . infoHash) d)),
39 ("peer_id", urlEncode peer_id),
46 in intercalate "&" [f ++ "=" ++ s | (f,s) <- p]
48 connect :: Url -> String -> IO String
49 connect baseurl qstr = let url = baseurl ++ "?" ++ qstr
50 in simpleHTTP (getRequest url) >>=