2 Backend (getCurrent,getList,get,setCurrent,update,listKeys)
5 ,Markup (Text, Paragraph, Link, Bold, Emph, Heading, Url, Underline, Strike, Pre)
14 import Text.ParserCombinators.Parsec
17 --Keyword -> (Full text,date)
18 getCurrent :: a -> String -> IO (Maybe (String,String))
20 --Keyword -> [(id,date,author,comment)]
21 getList :: a -> String -> IO [(String, String, String, String)]
23 --Keyword -> id -> Full text
24 get :: a -> String -> String -> IO (Maybe String)
27 setCurrent :: a -> String -> String -> IO Bool
29 --Keyword -> Full text -> id
30 update :: a -> String -> String -> String -> String -> IO String
33 listKeys :: a -> IO [String]
35 data Markup = Text String
40 | Heading Int [Markup]
46 type Document = [Markup]
48 wikiParser :: GenParser Char st Document
49 wikiParser = many1 pMain
51 pPara :: GenParser Char st Markup
52 pPara = count 2 pEol >> return (Paragraph)
54 pSpace :: GenParser Char st Markup
59 pLink :: GenParser Char st Markup
64 [] -> return (Link l l)
65 _ -> return (Link l d)
67 pHeading :: GenParser Char st Markup
70 level <- many1 $ char '='
72 s <- pStopAt (' ':level)
73 return (Heading (length level) s)
75 pURL :: GenParser Char st Markup
79 s <- many1 (alphaNum <|> oneOf "?.:&-/")
80 return (Url (proto++"://"++s))
82 pPre :: GenParser Char st Markup
83 pPre = string "<pre>" >> do
87 pBold,pEmph,pUnderline,pStrike :: GenParser Char st Markup
88 pBold = pS "**" (\s -> Bold s)
89 pEmph = pS "//" (\s -> Emph s)
90 pUnderline = pS "__" (\s -> Underline s)
91 pStrike = pS "--" (\s -> Strike s)
92 pS s f = string s >> do
96 pOtherChar :: GenParser Char st Markup
98 c <- oneOf "*,;.:!?[]()'\"=-%$£<>/\\|"
101 pText :: GenParser Char st Markup
106 pLinkContent :: GenParser Char st (String, String)
107 pLinkContent = do try (string "]]" >> return ([],[]))
114 (l,d) <- pLinkContent
117 pStopAt :: String -> GenParser Char st Document
118 pStopAt xs = pUntil pMain xs
120 pString :: String -> GenParser Char st String
121 pString xs = pUntil anyChar xs
123 pEol :: GenParser Char st String
124 pEol = string "\n" <|> string "\r\n"
126 pUntil :: GenParser Char st a -> String -> GenParser Char st [a]
127 pUntil p xs = manyTill p (try $ string xs)
129 pMain :: GenParser Char st Markup
145 newtype PGB = PGB DBService
147 createPGB :: String -> String -> String -> String -> IO PGB
148 createPGB host database user password = let db = createDBService host database "" user password Nothing in return (PGB db)
150 instance Backend PGB where
152 getCurrent (PGB db) key = do
153 result <- selectReturnTuples db $ "SELECT fulltext,timestamp FROM curtexts WHERE keyword="++tov key
155 [text,date]:_ -> return (Just (text,date))
158 getList (PGB db) key = do
159 list <- selectReturnTuples db $ "SELECT id, timestamp, author, comment from fulltexts WHERE keyword = "++tov key
162 _ -> return $ map (\[id,date,author,comment] -> (id,date,author,comment)) list
164 get (PGB db) key id = do
165 list <- selectReturnTuples db $ "SELECT fulltext from fulltexts WHERE id = "++tov id
167 [s]:_ -> return (Just s)
170 setCurrent (PGB db) key id = do
171 full <- selectReturnTuples db $ "SELECT keyword FROM fulltexts WHERE keyword="++tov key++" AND id='"++id++"'"
172 cur <- selectReturnTuples db $ "SELECT keyword FROM curtexts WHERE keyword="++tov key
179 execute db $ "INSERT INTO current (keyword, id) VALUES ("++tov key++","++tov id++")"
181 execute db $ "UPDATE current SET id = "++tov id++" WHERE keyword = "++tov key
182 if rows == 1 then return True
185 update (PGB db) key text author comment = do
186 rows <- execute db $ "INSERT INTO fulltexts (keyword,fulltext, author, comment) VALUES ("++tov key++","++tov text++","++tov author++","++tov comment++")"
187 if rows == 0 then return ""
189 [[id]] <- selectReturnTuples db $ "SELECT currval('fulltexts_id_seq')"
190 setCurrent (PGB db) key id
193 listKeys (PGB db) = do
194 list <- selectReturnTuples db $ "SELECT keyword FROM current keyword ORDER BY lower(keyword)"
197 _ -> mapM (\[key] -> return key) list
199 tov :: String -> String
200 tov s = '\'':escapeQuery s++"'"
202 toHtml :: [Markup] -> String
204 toHtml ((Paragraph):xs) = "<p>\n"++toHtml xs
205 toHtml ((Text s):xs) = s++toHtml xs
206 toHtml ((Link l d):xs) = "<link: "++l++" desc: "++d++">"++toHtml xs
207 toHtml ((Bold d):xs) = "<b>"++toHtml d++"</b>"++toHtml xs
208 toHtml ((Emph d):xs) = "<em>"++toHtml d++"</em>"++toHtml xs
209 toHtml ((Underline d):xs) = "<u>"++toHtml d++"</u>"++toHtml xs
210 toHtml ((Strike d):xs) = "<strike>"++toHtml d++"</strike>"++toHtml xs
211 toHtml ((Heading n d):xs) = "\n<h"++show n++">"++toHtml d++"</h"++show n++">\n"++toHtml xs
212 toHtml ((Url l):xs) = "<link: "++l++">"++toHtml xs
213 toHtml ((Pre s):xs) = "<pre>"++s++"</pre>"++toHtml xs
215 htmlOutput s = case parse wikiParser "" s of
216 Right n -> putStr (toHtml n)