module Get(readURL) where

-- A simple program which takes a URL, and returns its contents.

-- To compile this, you need to install the Haskell http package: 
--
-- http://www.haskell.org/http/

import Data.Char(intToDigit)
import Network.HTTP
import Network.URI
import System.Environment(getArgs)
import System.Exit(exitFailure)
import System.IO(hPutStrLn, stderr)

readURL :: String -> IO String
readURL uri = 
  case parseURI uri of 
    Nothing -> error "Could not parse URI."
    Just uri -> do 
      resp <- simpleHTTP (request uri)
      case resp of 
        Right resp -> 
          case rspCode resp of
            (2,0,0) -> do hPutStrLn stderr $ "Successfully read "++ show uri
                          return (rspBody resp)
            _ -> error (httpError resp)
        Left connerr -> error (show connerr)
    where
      showRspCode (a,b,c) = map intToDigit [a,b,c]
      httpError resp = showRspCode (rspCode resp) ++ " " ++ rspReason resp

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