2 Backend (getCurrent,getList,get,setCurrent,update,listKeys)
5 ,Markup (Text, Paragraph, Link, Bold, Emph, Heading, Url, Underline, Strike, Pre,List)
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]
47 type Document = [Markup]
49 wikiParser :: GenParser Char st Document
50 wikiParser = many1 pMain
52 pPara :: GenParser Char st Markup
53 pPara = count 2 pEol >> return (Paragraph)
55 pLink :: GenParser Char st Markup
60 [] -> return (Link l l)
61 _ -> return (Link l d)
63 pList :: GenParser Char st Markup
65 list <- many1 $ try pListItem
68 pListItem :: GenParser Char st [Markup]
74 pHeading :: GenParser Char st Markup
77 level <- many1 $ char '='
79 s <- pStopAt (' ':level)
80 return (Heading (length level) s)
82 pURL :: GenParser Char st Markup
86 s <- many1 (alphaNum <|> oneOf "?.:&-/")
87 return (Url (proto++"://"++s))
89 pMail :: GenParser Char st Markup
91 user <- many1 (alphaNum <|> oneOf ".-_")
93 server <- many1 (alphaNum <|> oneOf ".-_")
94 return (Url ("mailto:"++user++"@"++server))
97 pPre :: GenParser Char st Markup
98 pPre = string "<pre>" >> do
102 pBold,pEmph,pUnderline,pStrike :: GenParser Char st Markup
103 pBold = pS "**" (\s -> Bold s)
104 pEmph = pS "//" (\s -> Emph s)
105 pUnderline = pS "__" (\s -> Underline s)
106 pStrike = pS "--" (\s -> Strike s)
107 pS s f = string s >> do
111 pOtherChar :: GenParser Char st Markup
116 pText :: GenParser Char st Markup
121 pLinkContent :: GenParser Char st (String, String)
122 pLinkContent = do try (string "]]" >> return ([],[]))
129 (l,d) <- pLinkContent
132 pStopAt :: String -> GenParser Char st Document
133 pStopAt xs = pUntil pOneLine xs
135 pString :: String -> GenParser Char st String
136 pString xs = pUntil anyChar xs
138 pEol :: GenParser Char st Markup
140 (string "\n" <|> string "\r\n")
143 pUntil :: GenParser Char st a -> String -> GenParser Char st [a]
144 pUntil p xs = manyTill p (try $ string xs)
146 pMain :: GenParser Char st Markup
176 newtype PGB = PGB DBService
178 createPGB :: String -> String -> String -> String -> IO PGB
179 createPGB host database user password = let db = createDBService host database "" user password Nothing in return (PGB db)
181 instance Backend PGB where
183 getCurrent (PGB db) key = do
184 result <- selectReturnTuples db $ "SELECT fulltext,timestamp FROM curtexts WHERE keyword="++tov key
186 [text,date]:_ -> return (Just (text,date))
189 getList (PGB db) key = do
190 list <- selectReturnTuples db $ "SELECT id, timestamp, author, comment from fulltexts WHERE keyword = "++tov key
193 _ -> return $ map (\[id,date,author,comment] -> (id,date,author,comment)) list
195 get (PGB db) key id = do
196 list <- selectReturnTuples db $ "SELECT fulltext from fulltexts WHERE id = "++tov id
198 [s]:_ -> return (Just s)
201 setCurrent (PGB db) key id = do
202 full <- selectReturnTuples db $ "SELECT keyword FROM fulltexts WHERE keyword="++tov key++" AND id='"++id++"'"
203 cur <- selectReturnTuples db $ "SELECT keyword FROM curtexts WHERE keyword="++tov key
210 execute db $ "INSERT INTO current (keyword, id) VALUES ("++tov key++","++tov id++")"
212 execute db $ "UPDATE current SET id = "++tov id++" WHERE keyword = "++tov key
213 if rows == 1 then return True
216 update (PGB db) key text author comment = do
217 rows <- execute db $ "INSERT INTO fulltexts (keyword,fulltext, author, comment) VALUES ("++tov key++","++tov text++","++tov author++","++tov comment++")"
218 if rows == 0 then return ""
220 [[id]] <- selectReturnTuples db $ "SELECT currval('fulltexts_id_seq')"
221 setCurrent (PGB db) key id
224 listKeys (PGB db) = do
225 list <- selectReturnTuples db $ "SELECT keyword FROM current keyword ORDER BY lower(keyword)"
228 _ -> mapM (\[key] -> return key) list
230 tov :: String -> String
231 tov s = '\'':escapeQuery s++"'"
233 toHtml :: [Markup] -> String
235 toHtml ((Paragraph):xs) = "<p>\n"++toHtml xs
236 toHtml ((Text s):xs) = s++toHtml xs
237 toHtml ((Link l d):xs) = "<link: "++l++" desc: "++d++">"++toHtml xs
238 toHtml ((Bold d):xs) = "<b>"++toHtml d++"</b>"++toHtml xs
239 toHtml ((Emph d):xs) = "<em>"++toHtml d++"</em>"++toHtml xs
240 toHtml ((Underline d):xs) = "<u>"++toHtml d++"</u>"++toHtml xs
241 toHtml ((Strike d):xs) = "<strike>"++toHtml d++"</strike>"++toHtml xs
242 toHtml ((Heading n d):xs) = "\n<h"++show n++">"++toHtml d++"</h"++show n++">\n"++toHtml xs
243 toHtml ((Url l):xs) = "<link: "++l++">"++toHtml xs
244 toHtml ((Pre s):xs) = "<pre>"++s++"</pre>"++toHtml xs
245 toHtml ((List l):xs) = "<ul>\n"++(unlines $ map (\s -> "<li>"++toHtml s++"</li>\n") l) ++ "</ul>"++toHtml xs
247 htmlOutput s = case parse wikiParser "" s of
248 Right n -> putStr (toHtml n)