2 Backend (getCurrent,getList,get,setCurrent,update)
5 ,Markup (Text, Paragraph, Link, Bold, Emph, Heading, Url, Underline, Strike, Pre)
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]
42 type Document = [Markup]
44 wikiParser :: GenParser Char st Document
47 ss <- (wikiParser <|> return [])
60 pEol = char '\n' <|> do
64 pLinkParser = do try (string "]]" >> return ([],[]))
78 [] -> return (Link l l)
79 _ -> return (Link l d)
81 pBold = pS "**" (\s -> Bold s)
82 pEmph = pS "//" (\s -> Emph s)
83 pUnderline = pS "__" (\s -> Underline s)
84 pStrike = pS "--" (\s -> Strike s)
92 try (string xs >> return []) <|> (do
98 try (string xs >> return []) <|> (do
105 level <- many1 $ char '='
107 s <- pStopAt (' ':level)
108 return (Heading (length level) s)
111 proto <- many1 letter
113 s <- many1 (alphaNum <|> oneOf "?.:&-/")
114 return (Url (proto++"://"++s))
118 s <- pString "</pre>"
121 pMain = try (pHeading)
135 c <- oneOf "*,;.:!?[]()'\"=-%$£<>/\\|"
139 t <- many1 alphaNum--(noneOf ['\n','\r','[',']'])
143 newtype PGB = PGB DBService
145 createPGB :: String -> String -> String -> String -> IO PGB
146 createPGB host database user password = let db = createDBService host database "" user password Nothing in return (PGB db)
149 testDB = createPGB "wave" "wiki" "wiki" "12wiki34db"
151 instance Backend PGB where
153 getCurrent (PGB db) key = do
154 result <- selectReturnTuples db $ "SELECT fulltext,timestamp FROM curtexts WHERE keyword="++tov key
156 [text,date]:_ -> return (Just (text,date))
159 getList (PGB db) key = do
160 list <- selectReturnTuples db $ "SELECT id, timestamp, author, comment from fulltexts WHERE keyword = "++tov key
163 _ -> return $ map (\[id,date,author,comment] -> (id,date,author,comment)) list
165 get (PGB db) key id = do
166 list <- selectReturnTuples db $ "SELECT fulltext from fulltexts WHERE id = "++tov id
168 [s]:_ -> return (Just s)
171 setCurrent (PGB db) key id = do
172 full <- selectReturnTuples db $ "SELECT keyword FROM fulltexts WHERE keyword="++tov key++" AND id='"++id++"'"
173 cur <- selectReturnTuples db $ "SELECT keyword FROM curtexts WHERE keyword="++tov key
180 execute db $ "INSERT INTO current (keyword, id) VALUES ("++tov key++","++tov id++")"
182 execute db $ "UPDATE current SET id = "++tov id++" WHERE keyword = "++tov key
183 if rows == 1 then return True
186 update (PGB db) key text author comment = do
187 rows <- execute db $ "INSERT INTO fulltexts (keyword,fulltext, author, comment) VALUES ("++tov key++","++tov text++","++tov author++","++tov comment++")"
188 if rows == 0 then return ""
190 [[id]] <- selectReturnTuples db $ "SELECT currval('fulltexts_id_seq')"
191 setCurrent (PGB db) key id
195 tov :: String -> String
196 tov s = '\'':escapeQuery s++"'"