From 6789361c1ee570df06878535aff73d99b87528a5 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Mon, 25 Jun 2012 17:37:27 -0400
Subject: [PATCH] Begin working on determining the article argument type.

---
 lwn-epub.cabal     |  8 +++++++-
 src/CommandLine.hs |  7 +++++--
 src/Main.hs        | 48 +++++++++++++++++++++++++++++++++++-----------
 3 files changed, 49 insertions(+), 14 deletions(-)

diff --git a/lwn-epub.cabal b/lwn-epub.cabal
index 6eb0c4e..1879634 100644
--- a/lwn-epub.cabal
+++ b/lwn-epub.cabal
@@ -15,10 +15,16 @@ executable lwn-epub
     directory               == 1.1.*,
     filepath                == 1.3.*,
     HandsomeSoup            == 0.3.*,
+    HUnit                   == 1.2.*,
     hxt                     == 9.*,
     MissingH                == 1.1.*,
+    network                 == 2.3.*,
     pandoc                  == 1.9.*,
-    time                    == 1.*
+    regex-posix             == 0.95.*,
+    test-framework          == 0.6.*,
+    test-framework-hunit    == 0.2.*,
+    time                    == 1.*,
+    utf8-string             == 0.3.*
 
   main-is:
     Main.hs
diff --git a/src/CommandLine.hs b/src/CommandLine.hs
index a61cc30..4fd9a54 100644
--- a/src/CommandLine.hs
+++ b/src/CommandLine.hs
@@ -1,6 +1,6 @@
 {-# LANGUAGE DeriveDataTypeable #-}
 
-module CommandLine (Args(..), apply_args)
+module CommandLine (Args(..), apply_args, show_help)
 where
 
 -- Get the version from Cabal.
@@ -71,6 +71,9 @@ is_missing_arg_error s =
   startswith "Requires at least" s
 
 
+show_help :: IO (CmdArgs Args)
+show_help = withArgs ["--help"] parse_args
+
 parse_args :: IO (CmdArgs Args)
 parse_args = do
   x <- getArgs
@@ -80,7 +83,7 @@ parse_args = do
       Left err ->
         if (is_missing_arg_error err) then
           -- Disregard the error message, show help instead.
-          withArgs ["--help"] parse_args
+          show_help
         else do
           hPutStrLn stderr err
           exitWith (ExitFailure exit_args_parse_failed)
diff --git a/src/Main.hs b/src/Main.hs
index 373d423..655f1be 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -2,24 +2,44 @@
 module Main
 where
 
+import Prelude hiding (readFile)
+import System.Directory(doesFileExist)
 import System.IO (
   Handle,
   IOMode (WriteMode),
   openBinaryFile,
   stdout
   )
+import System.IO.UTF8 (readFile)
 import Text.XML.HXT.Core
 
-import CommandLine (Args(..), apply_args)
+import CommandLine (Args(..), apply_args, show_help)
 import LWN.Page
 
-my_read :: String -> IOStateArrow s b XmlTree
-my_read =
-  readDocument [ withValidate  no,
+
+my_read_opts :: SysConfigList
+my_read_opts = [ withValidate  no,
                  withParseHTML yes,
-                 withInputEncoding utf8,
                  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.
@@ -43,12 +63,18 @@ main :: IO ()
 main = do
   Args{..} <- apply_args
   output_handle <- get_output_handle output
-  input_path <- real_article_path article
-  let html = my_read input_path
-  result <- parse html
+  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     -> return ()
 
-  case result of
-    Just stuff  -> epublish stuff output_handle
-    Nothing     -> return ()
+    Nothing -> do
+      _ <- show_help
+      return ()
 
   putStrLn "Done."
-- 
2.44.2