Print an error before usage if we can't parse the page.

[dead/lwn-epub.git] / src / Main.hs

diff --git a/src/Main.hs b/src/Main.hs
index 47c69fa1cba9ade063d2b63bea22fe800b33a4e9..1f6d7c5f436a583d5143b05c1cf55aaf4126995e 100644 (file)
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -1,49 +1,25 @@
-{-# LANGUAGE ScopedTypeVariables, RecordWildCards #-}
+{-# LANGUAGE DoAndIfThenElse #-}
 module Main
 where
 
-import Prelude hiding (readFile)
+import Control.Concurrent.ParallelIO (stopGlobalPool)
 import System.Directory (doesFileExist)
 import System.IO (
   Handle,
   IOMode (WriteMode),
+  hPutStrLn,
   openBinaryFile,
+  stderr,
   stdout
   )
-import System.IO.UTF8 (readFile)
-import Text.Regex.Posix ((=~))
-import Text.XML.HXT.Core
 
 import CommandLine (show_help)
 import Configuration (Cfg(..), get_cfg)
-import LWN.Page
-import LWN.URI (is_lwn_url, make_absolute_url)
-import Misc (contains)
+import LWN.Article (real_article_path)
+import LWN.HTTP (get_login_cookie)
+import LWN.Page (epublish, page_from_url)
 
 
-my_read_opts :: SysConfigList
-my_read_opts = [ withValidate  no,
-                 withParseHTML yes,
-                 withWarnings no ]
-
--- | My version of HandsomeSoup's parseHTML.
-my_read :: String -> IOStateArrow s b XmlTree
-my_read = readString my_read_opts
-
--- | Try to parse the given article using HXT. We try a few different
---   methods; if none of them work, we return 'Nothing'.
-get_xml_from_article :: String -> IO (Maybe (IOStateArrow s b XmlTree))
-get_xml_from_article s = do
-  article <- real_article_path s
-  is_file <- doesFileExist article
-  case is_file of
-    True -> do
-      contents <- readFile article
-      return $ Just $ my_read contents
-    False -> do
-      -- Download the URL and try to parse it.
-      return Nothing
-
 -- | If we're given an empty path, return a handle to
 --   'stdout'. Otherwise, open the given file and return a read/write
 --   handle to that.
@@ -55,49 +31,28 @@ get_output_handle path =
     openBinaryFile path WriteMode
 
 
-
--- | Convert the given article to either a URL or a filesystem
---   path. If the given article exists on the filesystem, we assume
---   it's a file. Otherwise, we check to see if it's a URL. Failing
---   that, we try to construct a URL from what we're given and do our
---   best.
-real_article_path :: String -> IO String
-real_article_path s = do
-  is_file <- doesFileExist s
-  return $ if is_file then s else check_cases
-  where
-    abs_current =
-      case make_absolute_url "current" of
-        Nothing -> s
-        Just ac -> ac
-    abs_s =
-      case make_absolute_url s of
-        Nothing -> s
-        Just as -> as
-
-    check_cases :: String
-    check_cases
-      | is_lwn_url s = s
-      | s `contains` "current" = abs_current
-      | s =~ "^[0-9]+$" = abs_s
-      | otherwise = s -- Give up
+argument_is_file :: Cfg -> IO Bool
+argument_is_file cfg = do
+  path <- real_article_path (article cfg)
+  doesFileExist path
 
 main :: IO ()
 main = do
-  Cfg{..} <- get_cfg
-  output_handle <- get_output_handle output
-  maybe_html <- get_xml_from_article article
-
-  case maybe_html of
-
-    Just html -> do
-      result <- parse html
-      case result of
-        Just stuff  -> epublish stuff output_handle
-        Nothing     -> do
-         _ <- show_help
-         return ()
-
+  cfg' <- get_cfg
+  aif <- argument_is_file cfg'
+  cfg  <- case aif of
+           False -> get_login_cookie cfg'
+           True  -> return cfg'
+
+  page <- page_from_url cfg (article cfg)
+  case page of
+    Just p -> do
+      output_handle <- get_output_handle (output cfg)
+      epublish p output_handle
     Nothing -> do
+      hPutStrLn stderr "ERROR: could not parse an LWN page from the given URL."
       _ <- show_help
       return ()
+
+  -- Necessary, for some reason.
+  stopGlobalPool