{-# LANGUAGE TypeFamilies #-}
-- | Module: Poll
-- | Support for voting
-- |
-- | License: lGPL
-- |
-- | added by Kenneth Hoste (boegel), 22/11/2005
-- | inspiration: Where plugin (thanks shapr,dons)
module Lambdabot.Plugin.Social.Poll (pollPlugin) where
import Lambdabot.Plugin
import qualified Data.ByteString.Char8 as P
import Data.List
import qualified Data.Map as M
newPoll :: Poll
newPoll = (True,[])
appendPoll :: Choice -> Poll -> (Maybe Poll)
appendPoll choice (o,ls) = Just (o,(choice,0):ls)
voteOnPoll :: Poll -> Choice -> (Poll,String)
voteOnPoll (o,poll) choice =
if any (\(x,_) -> x == choice) poll
then ((o,map (\(c,n) ->
if c == choice then (c,n+1)
else (c,n)) poll)
,"voted on " ++ pprChoice choice)
else ((o,poll),pprChoice choice ++ " is not currently a candidate in this poll")
------------------------------------------------------------------------
type Count = Int
type Choice = P.ByteString
type PollName = P.ByteString
type Poll = (Bool, [(Choice, Count)])
type VoteState = M.Map PollName Poll
type VoteWriter = VoteState -> Cmd Vote ()
type Vote = ModuleT VoteState LB
------------------------------------------------------------------------
-- Define a serialiser
voteSerial :: Serial VoteState
voteSerial = Serial (Just . showPacked) (Just . readPacked)
------------------------------------------------------------------------
pollPlugin :: Module (M.Map PollName Poll)
pollPlugin = newModule
{ moduleCmds = return
[ (command "poll-list")
{ help = say "poll-list Shows all current polls"
, process = \_ -> do
result <- withMS $ \factFM writer -> processCommand factFM writer "poll-list" []
say result
}
, (command "poll-show")
{ help = say "poll-show <poll> Shows all choices for some poll"
, process = process_ "poll-show"
}
, (command "poll-add")
{ help = say "poll-add <name> Adds a new poll, with no candidates"
, process = process_ "poll-add"
}
, (command "choice-add")
{ help = say "choice-add <poll> <choice> Adds a new choice to the given poll"
, process = process_ "choice-add"
}
, (command "vote")
-- todo, should @vote foo automagically add foo as a possibility?
{ help = say "vote <poll> <choice> Vote for <choice> in <poll>"
, process = process_ "vote"
}
, (command "poll-result")
{ help = say "poll-result <poll> Show result for given poll"
, process = process_ "poll-result"
}
, (command "poll-close")
{ help = say "poll-close <poll> Closes a poll"
, process = process_ "poll-close"
}
, (command "poll-remove")
{ help = say "poll-remove <poll> Removes a poll"
, process = process_ "poll-remove"
}
, (command "poll-reset")
{ help = say "poll-reset <poll> Resets votes and reopens a poll"
, process = process_ "poll-reset"
}
]
, moduleDefState = return M.empty
, moduleSerialize = Just voteSerial
}
process_ :: [Char] -> [Char] -> Cmd Vote ()
process_ cmd [] = say ("Missing argument. Check @help " ++ cmd ++ " for info.")
process_ cmd dat
| any (\c -> c < ' ' || c == '"') dat
= say "Please do not use control characters or double quotes in polls."
process_ cmd dat = do
result <- withMS $ \fm writer ->
processCommand fm writer cmd (map P.pack (words dat))
say result
------------------------------------------------------------------------
processCommand :: VoteState -> VoteWriter -> String -> [P.ByteString] -> Cmd Vote String
processCommand fm writer cmd dat = case cmd of
-- show all current polls
"poll-list" -> return $ listPolls fm
-- show candidates
"poll-show" -> return $ case dat of
[poll] -> showPoll fm poll
_ -> "usage: @poll-show <poll>"
-- declare a new poll
"poll-add" -> case dat of
[poll] -> addPoll fm writer poll
_ -> return "usage: @poll-add <poll> with \"ThisTopic\" style names"
"choice-add" -> case dat of
[poll,choice] -> addChoice fm writer poll choice
_ -> return "usage: @choice-add <poll> <choice>"
"vote" -> case dat of
[poll,choice] -> vote fm writer poll choice
_ -> return "usage: @vote <poll> <choice>"
"poll-result" -> return $ case dat of
[poll] -> showResult fm poll
_ -> "usage: @poll-result <poll>"
"poll-close" -> case dat of
[poll] -> closePoll fm writer poll
_ -> return "usage: @poll-close <poll>"
"poll-remove" -> case dat of
[poll] -> removePoll fm writer poll
_ -> return "usage: @poll-remove <poll>"
"poll-reset" -> case dat of
[poll] -> resetPoll fm writer poll
_ -> return "usage: @poll-reset <poll>"
_ -> return "Unknown command."
------------------------------------------------------------------------
listPolls :: VoteState -> String
listPolls fm = pprList pprPoll $ map fst (M.toList fm)
showPoll :: VoteState -> PollName -> String
showPoll fm poll =
case M.lookup poll fm of
Nothing -> "No such poll: " ++ pprPoll poll ++ " Use @poll-list to see the available polls."
Just p -> pprList pprChoice $ map fst (snd p)
addPoll :: VoteState -> VoteWriter -> PollName -> Cmd Vote String
addPoll fm writer poll =
case M.lookup poll fm of
Nothing -> do writer $ M.insert poll newPoll fm
return $ "Added new poll: " ++ pprPoll poll
Just _ -> return $ "Poll " ++ pprPoll poll ++
" already exists, choose another name for your poll"
addChoice :: VoteState -> VoteWriter -> PollName -> Choice -> Cmd Vote String
addChoice fm writer poll choice = case M.lookup poll fm of
Nothing -> return $ "No such poll: " ++ pprPoll poll
Just _ -> do writer $ M.update (appendPoll choice) poll fm
return $ "New candidate " ++ pprChoice choice ++
", added to poll " ++ pprPoll poll ++ "."
vote :: VoteState -> VoteWriter -> PollName -> Choice -> Cmd Vote String
vote fm writer poll choice = case M.lookup poll fm of
Nothing -> return $ "No such poll: " ++ pprPoll poll
Just (False,_) -> return $ "The "++ pprPoll poll ++ " poll is closed, sorry !"
Just p@(True,_) -> do let (np,msg) = voteOnPoll p choice
writer $ M.update (const (Just np)) poll fm
return msg
showResult :: VoteState -> PollName -> String
showResult fm poll = case M.lookup poll fm of
Nothing -> "No such poll: " ++ pprPoll poll
Just (o,p) -> "Poll results for " ++ pprPoll poll ++ " (" ++ status o ++ "): "
++ (concat $ intersperse ", " $ map ppr p)
where
status s | s = "Open"
| otherwise = "Closed"
ppr (x,y) = pprChoice x ++ "=" ++ show y
removePoll :: VoteState -> VoteWriter -> PollName -> Cmd Vote String
removePoll fm writer poll = case M.lookup poll fm of
Just (True,_) -> return "Poll should be closed before you can remove it."
Just (False,_) -> do writer $ M.delete poll fm
return $ "poll " ++ pprPoll poll ++ " removed."
Nothing -> return $ "No such poll: " ++ pprPoll poll
closePoll :: VoteState -> VoteWriter -> PollName -> Cmd Vote String
closePoll fm writer poll = case M.lookup poll fm of
Nothing -> return $ "No such poll: " ++ pprPoll poll
Just (_,p) -> do writer $ M.update (const (Just (False,p))) poll fm
return $ "Poll " ++ pprPoll poll ++ " closed."
resetPoll :: VoteState -> VoteWriter -> PollName -> Cmd Vote String
resetPoll fm writer poll = case M.lookup poll fm of
Just (_, vs) -> do let np = (True, map (\(c, _) -> (c, 0)) vs)
writer $ M.update (const (Just np)) poll fm
return $ "Poll " ++ pprPoll poll ++ " reset."
Nothing -> return $ "No such poll: " ++ pprPoll poll
------------------------------------------------------------------------
-- we render strings verbatim but surround them with quotes,
-- relying on previous sanitization to disallow control characters
pprBS :: P.ByteString -> String
pprBS p = "\"" ++ P.unpack p ++ "\""
pprPoll :: PollName -> String
pprPoll = pprBS
pprChoice :: Choice -> String
pprChoice = pprBS
pprList :: (a -> String) -> [a] -> String
pprList f as = "[" ++ concat (intersperse "," (map f as)) ++ "]"