{-# LANGUAGE TypeFamilies #-}
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 :: String -> Poll -> (Maybe Poll)
appendPoll choice (o,ls) = Just (o,(choice,0):ls)
voteOnPoll :: Poll -> String -> (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 " ++ show choice)
else ((o,poll),show choice ++ " is not currently a candidate in this poll")
type Count = Int
type Candidate = String
type PollName = P.ByteString
type Poll = (Bool, [(Candidate, Count)])
type VoteState = M.Map PollName Poll
type VoteWriter = VoteState -> Cmd Vote ()
type Vote = ModuleT VoteState LB
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")
{ 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"
}
]
, 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 = do
result <- withMS $ \fm writer -> processCommand fm writer cmd (words dat)
say result
processCommand :: VoteState -> VoteWriter -> String -> [String] -> Cmd Vote String
processCommand fm writer cmd dat = case cmd of
"poll-list" -> return $ listPolls fm
"poll-show" -> return $ case length dat of
1 -> showPoll fm (head dat)
_ -> "usage: @poll-show <poll>"
"poll-add" -> case length dat of
1 -> addPoll fm writer (head dat)
_ -> return "usage: @poll-add <poll> with \"ThisTopic\" style names"
"choice-add" -> case length dat of
2 -> addChoice fm writer (head dat) (last dat)
_ -> return "usage: @choice-add <poll> <choice>"
"vote" -> case length dat of
2 -> vote fm writer (head dat) (last dat)
_ -> return "usage: @vote <poll> <choice>"
"poll-result" -> return $ case length dat of
1 -> showResult fm (head dat)
_ -> "usage: @poll-result <poll>"
"poll-close" -> case length dat of
1 -> closePoll fm writer (head dat)
_ -> return "usage: @poll-close <poll>"
"poll-remove" -> case length dat of
1 -> removePoll fm writer (head dat)
_ -> return "usage: @poll-remove <poll>"
_ -> return "Unknown command."
listPolls :: VoteState -> String
listPolls fm = show $ map fst (M.toList fm)
showPoll :: VoteState -> String -> String
showPoll fm poll =
case M.lookup (P.pack poll) fm of
Nothing -> "No such poll: " ++ show poll ++ " Use @poll-list to see the available polls."
Just p -> show $ map fst (snd p)
addPoll :: VoteState -> VoteWriter -> String -> Cmd Vote String
addPoll fm writer poll =
case M.lookup (P.pack poll) fm of
Nothing -> do writer $ M.insert (P.pack poll) newPoll fm
return $ "Added new poll: " ++ show poll
Just _ -> return $ "Poll " ++ show poll ++
" already exists, choose another name for your poll"
addChoice :: VoteState -> VoteWriter -> String -> String -> Cmd Vote String
addChoice fm writer poll choice = case M.lookup (P.pack poll) fm of
Nothing -> return $ "No such poll: " ++ show poll
Just _ -> do writer $ M.update (appendPoll choice) (P.pack poll) fm
return $ "New candidate " ++ show choice ++
", added to poll " ++ show poll ++ "."
vote :: VoteState -> VoteWriter -> String -> String -> Cmd Vote String
vote fm writer poll choice = case M.lookup (P.pack poll) fm of
Nothing -> return $ "No such poll:" ++ show poll
Just (False,_) -> return $ "The "++ show poll ++ " poll is closed, sorry !"
Just p@(True,_) -> do let (np,msg) = voteOnPoll p choice
writer $ M.update (const (Just np)) (P.pack poll) fm
return msg
showResult :: VoteState -> String -> String
showResult fm poll = case M.lookup (P.pack poll) fm of
Nothing -> "No such poll: " ++ show poll
Just (o,p) -> "Poll results for " ++ poll ++ " (" ++ (status o) ++ "): "
++ (concat $ intersperse ", " $ map ppr p)
where
status s | s = "Open"
| otherwise = "Closed"
ppr (x,y) = x ++ "=" ++ show y
removePoll :: VoteState -> VoteWriter -> String -> Cmd Vote String
removePoll fm writer poll = case M.lookup (P.pack poll) fm of
Just (True,_) -> return "Poll should be closed before you can remove it."
Just (False,_) -> do writer $ M.delete (P.pack poll) fm
return $ "poll " ++ show poll ++ " removed."
Nothing -> return $ "No such poll: " ++ show poll
closePoll :: VoteState -> VoteWriter -> String -> Cmd Vote String
closePoll fm writer poll = case M.lookup (P.pack poll) fm of
Nothing -> return $ "No such poll: " ++ show poll
Just (_,p) -> do writer $ M.update (const (Just (False,p))) (P.pack poll) fm
return $ "Poll " ++ show poll ++ " closed."