2 Backend (getCurrent,getList,get,setCurrent,update)
5 ,Markup (Text, Paragraph, Link, Bold, Emph, Heading, Url, Underline, Strike)
13 import Text.ParserCombinators.Parsec
16 --Keyword -> (Full text,date)
17 getCurrent :: a -> String -> IO (Maybe (String,String))
19 --Keyword -> [(id,date,author,comment)]
20 getList :: a -> String -> IO [(String, String, String, String)]
22 --Keyword -> id -> Full text
23 get :: a -> String -> String -> IO (Maybe String)
26 setCurrent :: a -> String -> String -> IO Bool
28 --Keyword -> Full text -> id
29 update :: a -> String -> String -> String -> String -> IO String
31 data Markup = Text String
36 | Heading Int [Markup]
41 type Document = [Markup]
43 wikiParser :: GenParser Char st Document
46 ss <- (wikiParser <|> return [])
59 pEol = char '\n' <|> do
63 pLinkParser = do try (string "]]" >> return ([],[]))
77 [] -> return (Link l l)
78 _ -> return (Link l d)
80 pBold = pS "**" (\s -> Bold s)
81 pEmph = pS "//" (\s -> Emph s)
82 pUnderline = pS "__" (\s -> Underline s)
83 pStrike = pS "--" (\s -> Strike s)
91 try (string xs >> return []) <|> (do
97 try (string xs >> return []) <|> (do
104 level <- many1 $ char '='
106 s <- pStopAt (' ':level)
107 return (Heading (length level) s)
110 proto <- many1 letter
112 s <- many1 (alphaNum <|> oneOf "?.:&-/")
113 return (Url (proto++"://"++s))
115 pMain = try (pHeading)
128 c <- oneOf "*,;.:!?[]()'\"=-%$£<>/\\|"
132 t <- many1 alphaNum--(noneOf ['\n','\r','[',']'])
136 newtype PGB = PGB DBService
138 createPGB :: String -> String -> String -> String -> IO PGB
139 createPGB host database user password = let db = createDBService host database "" user password Nothing in return (PGB db)
142 testDB = createPGB "wave" "wiki" "wiki" "12wiki34db"
144 instance Backend PGB where
146 getCurrent (PGB db) key = do
147 result <- selectReturnTuples db $ "SELECT fulltext,timestamp FROM curtexts WHERE keyword="++tov key
149 [text,date]:_ -> return (Just (text,date))
152 getList (PGB db) key = do
153 list <- selectReturnTuples db $ "SELECT id, timestamp, author, comment from fulltexts WHERE keyword = "++tov key
156 _ -> return $ map (\[id,date,author,comment] -> (id,date,author,comment)) list
158 get (PGB db) key id = do
159 list <- selectReturnTuples db $ "SELECT fulltext from fulltexts WHERE id = "++tov id
161 [s]:_ -> return (Just s)
164 setCurrent (PGB db) key id = do
165 full <- selectReturnTuples db $ "SELECT keyword FROM fulltexts WHERE keyword="++tov key++" AND id='"++id++"'"
166 cur <- selectReturnTuples db $ "SELECT keyword FROM curtexts WHERE keyword="++tov key
173 execute db $ "INSERT INTO current (keyword, id) VALUES ("++tov key++","++tov id++")"
175 execute db $ "UPDATE current SET id = "++tov id++" WHERE keyword = "++tov key
176 if rows == 1 then return True
179 update (PGB db) key text author comment = do
180 rows <- execute db $ "INSERT INTO fulltexts (keyword,fulltext, author, comment) VALUES ("++tov key++","++tov text++","++tov author++","++tov comment++")"
181 if rows == 0 then return ""
183 [[id]] <- selectReturnTuples db $ "SELECT currval('fulltexts_id_seq')"
184 setCurrent (PGB db) key id
188 tov :: String -> String
189 tov s = '\'':escapeQuery s++"'"