-- based on code from http://darcs.haskell.org/http/test/get.hs

import Data.Char (intToDigit)
import Network.HTTP
import Network.URI
import Network.Stream (ConnError)
import System.Environment (getArgs)
import System.Exit (exitFailure)
import System.IO (hPutStrLn, stderr, openFile, IOMode(..), hPutStr, hClose)
import Data.Maybe (isNothing)
import VotesUtil

voteYear = 2005
voteGetDir = "http://clerk.house.gov/evs/" ++ (show voteYear) ++ "/"
maxVoteNum = 671 -- TODO - figure this out
-- maxVoteNum = 543 -- TODO - figure this out
-- maxVoteNum = 175 -- TODO - figure this out

getDestFilename :: Int -> String
getDestFilename num = fileNameFromVoteIndex (VoteIndex voteYear num)

getTargetFilename :: Int -> String
getTargetFilename num = voteGetDir ++ "roll" ++ (padString 3 "0" (show num)) ++ ".xml"

getTargetURI :: Int -> Maybe URI
getTargetURI num = parseURI (getTargetFilename num)

getTargetFile :: Int -> IO ()
getTargetFile num = case getTargetURI num of
                           Nothing -> err ("Could not parse URI for number " ++ (show num))
                           Just uri -> do
                               text <- get uri
                               writeFile (getDestFilename num) text

downloadAll :: IO ()
downloadAll = sequence_ (map getTargetFile [1..maxVoteNum])

--downloadURI :: Int -> Maybe (IO Bool)
--downloadURI num = let target = getTargetURI num
--                  in if (isNothing(target))
--                     then Nothing
--                     else do blah <- map getTargetFile [1..maxVoteNum]
--                             return Just True


main = do downloadAll
--main = writeFile "samplefile.txt" "sampletext"
--main = 
--    do
--    args <- getArgs
--    case args of 
--        [addr] -> case parseURI addr of
--                    Nothing -> err "Could not parse URI"
--                    Just uri -> do
--                        cont <- get uri
--                        putStr cont
--         _ -> err "Usage: get <url>"

err :: String -> IO a
err msg = do 
      hPutStrLn stderr msg
      exitFailure

get :: URI -> IO String
get uri =
    do
    eresp <- simpleHTTP (request uri)
    resp <- handleE (err . show) eresp
    case rspCode resp of
                      (2,0,0) -> return (rspBody resp)
                      _ -> err (httpError resp)
    where
    showRspCode (a,b,c) = map intToDigit [a,b,c]
    httpError resp = showRspCode (rspCode resp) ++ " " ++ rspReason resp

request :: URI -> Request String
request uri = Request{ rqURI = uri,
                       rqMethod = GET,
                       rqHeaders = [],
                       rqBody = "" }

handleE :: Monad m => (ConnError -> m a) -> Either ConnError a -> m a
handleE h (Left e) = h e
handleE _ (Right v) = return v