[Fencommits] fenserve: make more robust by checking always before doing a (make run)

[Benja Fallenstein]

Sat Apr 28 21:57:23 EEST 2007  Benja Fallenstein <benja.fallenstein at gmail.com>
  * make more robust by checking always before doing a (make run)
diff -rN -u old-fenserve/notetaker/Main.hs new-fenserve/notetaker/Main.hs
--- old-fenserve/notetaker/Main.hs	2007-04-28 21:57:33.000000000 +0300
+++ new-fenserve/notetaker/Main.hs	2007-04-28 21:57:33.000000000 +0300
@@ -34,7 +34,7 @@
             \    document.forms[0].elements[1].focus();\
             \</script>"
 
-views n nick = "<p>Views: "++concat (intersperse " | " [view i|i<-[0..2]])
+views n nick = "<p>Views: "++concat (intersperse " | " [view i|i<-[0..length links-1]])
     where links = [("main", "/"), ("log", "/log"), ("lastlog", "/lastlog")]
           view i | i == n    = printf "<b>%s</b>" name
                  | otherwise = printf "<a href=%s?nick=%s>%s</a>" uri nick name
@@ -42,13 +42,15 @@
 
 page path nick = do 
     (lines :: [Line]) <- get
-    let Note title _ notes =
-            getPath path $ foldl (flip execute) (Note "HOME" True []) lines
-    respond $ style ++ "<h2>" ++ renderPath path ++ " " ++ title ++ "</h2>"
-           ++ renderNotes path nick notes ++ views 0 nick ++ form nick
-           
-getPath [] note = note
-getPath (i:is) (Note _ _ cs) = getPath is (cs !! i)
+    case getPath path $ executeAll lines of
+      Just (Note title _ notes) ->
+        respond $ style ++ "<h2>" ++ renderPath path ++ " " ++ title ++ "</h2>"
+               ++ renderNotes path nick notes ++ views 0 nick ++ form nick
+      Nothing -> respond $ "Path not found: " ++ renderPath path
+
+getPath [] note = Just note
+getPath (i:is) (Note _ _ cs) | i >= 0 && i < length cs = getPath is (cs !! i)
+                             | otherwise = Nothing
                     
 renderNotes p nick notes = 
     "<ol>" ++ concat [renderNote (p++[i]) (notes !! i) 
@@ -80,9 +82,10 @@
            | ":unpage "  `isPrefixOf` s = readPath' s 8 $ \p "" -> Unpage p
            | otherwise               = Body s
     
-execute (Line _ _ (Body _)) = id
-execute (Line _ _ body) =
-    case body of 
+executeAll = foldl (\n (Line _ _ b) -> execute b n) (Note "HOME" True [])
+
+execute (Body _) = id
+execute body = case body of 
         Add p l       -> on p $ \(Note t o cs) -> [Note t o (cs++[Note l False []])]
         Edit p l      -> on p $ \(Note _ o cs) -> [Note l o cs]
         Move p q      -> move p q
@@ -94,12 +97,14 @@
   where
     on is f note = head $ on' is f note
     on' []     f note        = f note
-    on' (i:is) f (Note t o cs) = 
+    on' (i:is) f (Note t o cs) | i < 0 || i >= length cs = [Note t o cs]
+                               | otherwise =
           [Note t o (take i cs ++ on' is f (cs !! i) ++ drop (i+1) cs)]
               
-    move p q root = (on p $ \(Note _ _ cs) -> [])
-                  $ (on q $ \(Note t o cs) -> [Note t o (cs++[getPath p root])])
-                  $ root
+    move p q root = case getPath p root of
+        Nothing -> root
+        Just n  -> (on p $ \(Note _ _ cs) -> []) $
+                   (on q $ \(Note t o cs) -> [Note t o (cs++[n])]) $ root
 
 getNick m = case lookM m "nick" of Nothing -> "(anon)"; Just "" -> "(anon)"
                                    Just x  -> x