{-# LANGUAGE OverloadedStrings #-}

module Actions where

import Control.Concurrent

import Control.Concurrent.Chan

import qualified Data.IntSet as IntSet

import qualified Data.Set as Set

import qualified Data.Sequence as Seq

import System.Log.Logger

import Control.Monad

import Data.Time

import Data.Maybe

import Control.Monad.Reader

import Control.Monad.State.Strict

import qualified Data.ByteString.Char8 as B

import Control.DeepSeq

-----------------------------

import CoreTypes

import Utils

import ClientIO

import ServerState

data Action =

    AnswerClients ![ClientChan] ![B.ByteString]

    | SendServerMessage

    | SendServerVars

    | MoveToRoom RoomIndex

    | MoveToLobby B.ByteString

    | RemoveTeam B.ByteString

    | RemoveRoom

    | UnreadyRoomClients

    | JoinLobby

    | ProtocolError B.ByteString

    | Warning B.ByteString

    | ByeClient B.ByteString

    | KickClient ClientIndex

    | KickRoomClient ClientIndex

    | BanClient B.ByteString -- nick

    | RemoveClientTeams ClientIndex

    | ModifyClient (ClientInfo -> ClientInfo)

    | ModifyClient2 ClientIndex (ClientInfo -> ClientInfo)

    | ModifyRoom (RoomInfo -> RoomInfo)

    | ModifyServerInfo (ServerInfo -> ServerInfo)

    | AddRoom B.ByteString B.ByteString

    | CheckRegistered

    | ClearAccountsCache

    | ProcessAccountInfo AccountInfo

    | AddClient ClientInfo

    | DeleteClient ClientIndex

    | PingAll

    | StatsAction

type CmdHandler = [B.ByteString] -> Reader (ClientIndex, IRnC) [Action]

instance NFData Action where

    rnf (AnswerClients chans msg) = chans `deepseq` msg `deepseq` ()

    rnf a = a `seq` ()

instance NFData B.ByteString

instance NFData (Chan a)

othersChans = do

    cl <- client's id

    ri <- clientRoomA

    liftM (map sendChan . filter (/= cl)) $ roomClientsS ri

processAction :: Action -> StateT ServerState IO ()

processAction (AnswerClients chans msg) = do

    io $ mapM_ (flip writeChan (msg `deepseq` msg)) (chans `deepseq` chans)

processAction SendServerMessage = do

    chan <- client's sendChan

    protonum <- client's clientProto

    si <- liftM serverInfo get

    let message = if protonum < latestReleaseVersion si then

            serverMessageForOldVersions si

            else

            serverMessage si

    processAction $ AnswerClients [chan] ["SERVER_MESSAGE", message]

processAction SendServerVars = do

    chan <- client's sendChan

    si <- gets serverInfo

    io $ writeChan chan ("SERVER_VARS" : vars si)

    where

        vars si = [

            "MOTD_NEW", serverMessage si,

            "MOTD_OLD", serverMessageForOldVersions si,

            "LATEST_PROTO", B.pack . show $ latestReleaseVersion si

            ]

processAction (ProtocolError msg) = do

    chan <- client's sendChan

    processAction $ AnswerClients [chan] ["ERROR", msg]

processAction (Warning msg) = do

    chan <- client's sendChan

    processAction $ AnswerClients [chan] ["WARNING", msg]

processAction (ByeClient msg) = do

    (Just ci) <- gets clientIndex

    rnc <- gets roomsClients

    ri <- clientRoomA

    chan <- client's sendChan

    clNick <- client's nick

    when (ri /= lobbyId) $ do

        processAction $ MoveToLobby ("quit: " `B.append` msg)

        return ()

    clientsChans <- liftM (Prelude.map sendChan . Prelude.filter logonPassed) $! allClientsS

    io $ do

        infoM "Clients" (show ci ++ " quits: " ++ (B.unpack msg))

    processAction $ AnswerClients [chan] ["BYE", msg]

    processAction $ AnswerClients clientsChans ["LOBBY:LEFT", clNick, msg]

    s <- get

    put $! s{removedClients = ci `Set.insert` removedClients s}

processAction (DeleteClient ci) = do

    rnc <- gets roomsClients

    io $ removeClient rnc ci

    s <- get

    put $! s{removedClients = ci `Set.delete` removedClients s}

processAction (ModifyClient f) = do

    (Just ci) <- gets clientIndex

    rnc <- gets roomsClients

    io $ modifyClient rnc f ci

    return ()

processAction (ModifyClient2 ci f) = do

    rnc <- gets roomsClients

    io $ modifyClient rnc f ci

    return ()

processAction (ModifyRoom f) = do

    rnc <- gets roomsClients

    ri <- clientRoomA

    io $ modifyRoom rnc f ri

    return ()

processAction (ModifyServerInfo f) =

    modify (\s -> s{serverInfo = f $ serverInfo s})

processAction (MoveToRoom ri) = do

    (Just ci) <- gets clientIndex

    rnc <- gets roomsClients

    io $ do

        modifyClient rnc (\cl -> cl{teamsInGame = 0, isReady = False, isMaster = False}) ci

        modifyRoom rnc (\r -> r{playersIn = (playersIn r) + 1}) ri

        moveClientToRoom rnc ri ci

    chans <- liftM (map sendChan) $ roomClientsS ri

    clNick <- client's nick

    processAction $ AnswerClients chans ["JOINED", clNick]

processAction (MoveToLobby msg) = do

    (Just ci) <- gets clientIndex

    ri <- clientRoomA

    rnc <- gets roomsClients

    room <- clientRoomA

    ready <- client's isReady

    master <- client's isMaster

    client <- client's id

    if master then

        processAction RemoveRoom

        else

        do

        clNick <- client's nick

        clChan <- client's sendChan

        chans <- othersChans

        mapM_ processAction [AnswerClients chans ["LEFT", clNick, msg], RemoveClientTeams ci]

    io $ do

            modifyRoom rnc (\r -> r{

                    playersIn = (playersIn r) - 1,

                    readyPlayers = if ready then readyPlayers r - 1 else readyPlayers r

                    }) ri

            moveClientToLobby rnc ci

{-

    (_, _, newClients, newRooms) <-

            if isMaster client then

                if (gameinprogress room) && (playersIn room > 1) then

                    (changeMaster >>= (\state -> foldM processAction state

                        [AnswerOthersInRoom ["LEFT", nick client, msg],

                        AnswerOthersInRoom ["WARNING", "Admin left the room"],

                        RemoveClientTeams clID]))

                else -- not in game

                    processAction (clID, serverInfo, rnc) RemoveRoom

            else -- not master

                foldM

                    processAction

                        (clID, serverInfo, rnc)

                        [AnswerOthersInRoom ["LEFT", nick client, msg],

                        RemoveClientTeams clID]

    return (

        clID,

        serverInfo,

        adjust resetClientFlags clID newClients,

        adjust removeClientFromRoom rID $ adjust insertClientToRoom 0 newRooms

        )

    where

        rID = roomID client

        client = clients ! clID

        room = rooms ! rID

        resetClientFlags cl = cl{roomID = 0, isMaster = False, isReady = False, teamsInGame = undefined}

        removeClientFromRoom r = r{

                playersIDs = otherPlayersSet,

                playersIn = (playersIn r) - 1,

                readyPlayers = if isReady client then (readyPlayers r) - 1 else readyPlayers r

                }

        insertClientToRoom r = r{playersIDs = IntSet.insert clID (playersIDs r)}

        changeMaster = do

            processAction (newMasterId, serverInfo, rnc) $ AnswerThisClient ["ROOM_CONTROL_ACCESS", "1"]

            return (

                clID,

                serverInfo,

                adjust (\cl -> cl{isMaster = True}) newMasterId clients,

                adjust (\r -> r{masterID = newMasterId, name = newRoomName}) rID rooms

                )

        newRoomName = nick newMasterClient

        otherPlayersSet = IntSet.delete clID (playersIDs room)

        newMasterId = IntSet.findMin otherPlayersSet

        newMasterClient = clients ! newMasterId

-}

processAction (AddRoom roomName roomPassword) = do

    Just clId <- gets clientIndex

    rnc <- gets roomsClients

    proto <- io $ client'sM rnc clientProto clId

    let room = newRoom{

            masterID = clId,

            name = roomName,

            password = roomPassword,

            roomProto = proto

            }

    rId <- io $ addRoom rnc room

    processAction $ MoveToRoom rId

    chans <- liftM (map sendChan) $! roomClientsS lobbyId

    mapM_ processAction [

        AnswerClients chans ["ROOM", "ADD", roomName]

        , ModifyClient (\cl -> cl{isMaster = True})

        ]

processAction RemoveRoom = do

    Just clId <- gets clientIndex

    rnc <- gets roomsClients

    ri <- io $ clientRoomM rnc clId

    roomName <- io $ room'sM rnc name ri

    others <- othersChans

    lobbyChans <- liftM (map sendChan) $! roomClientsS lobbyId

    mapM_ processAction [

            AnswerClients lobbyChans ["ROOM", "DEL", roomName],

            AnswerClients others ["ROOMABANDONED", roomName]

        ]

    io $ removeRoom rnc ri

processAction (UnreadyRoomClients) = do

    rnc <- gets roomsClients

    ri <- clientRoomA

    roomPlayers <- roomClientsS ri

    roomClIDs <- io $ roomClientsIndicesM rnc ri

    processAction $ AnswerClients (map sendChan roomPlayers) ("NOT_READY" : map nick roomPlayers)

    io $ mapM_ (modifyClient rnc (\cl -> cl{isReady = False})) roomClIDs

    processAction $ ModifyRoom (\r -> r{readyPlayers = 0})

processAction (RemoveTeam teamName) = do

    rnc <- gets roomsClients

    cl <- client's id

    ri <- clientRoomA

    inGame <- io $ room'sM rnc gameinprogress ri

    chans <- othersChans

    if inGame then

            mapM_ processAction [

                AnswerClients chans ["REMOVE_TEAM", teamName],

                ModifyRoom (\r -> r{teams = Prelude.filter (\t -> teamName /= teamname t) $ teams r})

                ]

        else

            mapM_ processAction [

                AnswerClients chans ["EM", rmTeamMsg],

                ModifyRoom (\r -> r{

                    teams = Prelude.filter (\t -> teamName /= teamname t) $ teams r,

                    leftTeams = teamName : leftTeams r,

                    roundMsgs = roundMsgs r Seq.|> rmTeamMsg

                    })

                ]

    where

        rmTeamMsg = toEngineMsg $ (B.singleton 'F') `B.append` teamName

processAction (RemoveClientTeams clId) = do

    rnc <- gets roomsClients

    removeTeamActions <- io $ do

        clNick <- client'sM rnc nick clId

        rId <- clientRoomM rnc clId

        roomTeams <- room'sM rnc teams rId

        return . Prelude.map (RemoveTeam . teamname) . Prelude.filter (\t -> teamowner t == clNick) $ roomTeams

    mapM_ processAction removeTeamActions

processAction CheckRegistered = do

    (Just ci) <- gets clientIndex

    n <- client's nick

    h <- client's host

    db <- gets (dbQueries . serverInfo)

    io $ writeChan db $ CheckAccount ci n h

    return ()

processAction ClearAccountsCache = do

    dbq <- gets (dbQueries . serverInfo)

    io $ writeChan dbq ClearCache

    return ()

processAction (ProcessAccountInfo info) =

    case info of

        HasAccount passwd isAdmin -> do

            chan <- client's sendChan

            processAction $ AnswerClients [chan] ["ASKPASSWORD"]

        Guest -> do

            processAction JoinLobby

        Admin -> do

            mapM processAction [ModifyClient (\cl -> cl{isAdministrator = True}), JoinLobby]

            chan <- client's sendChan

            processAction $ AnswerClients [chan] ["ADMIN_ACCESS"]

processAction JoinLobby = do

    chan <- client's sendChan

    clientNick <- client's nick

    (lobbyNicks, clientsChans) <- liftM (unzip . Prelude.map (\c -> (nick c, sendChan c)) . Prelude.filter logonPassed) $! allClientsS

    mapM_ processAction $

        (AnswerClients clientsChans ["LOBBY:JOINED", clientNick])

        : [AnswerClients [chan] ("LOBBY:JOINED" : clientNick : lobbyNicks)]

        ++ [ModifyClient (\cl -> cl{logonPassed = True}), SendServerMessage]

{-

processAction (clID, serverInfo, rnc) (RoomAddThisClient rID) =

    processAction (

        clID,

        serverInfo,

        adjust (\cl -> cl{roomID = rID, teamsInGame = if rID == 0 then teamsInGame cl else 0}) clID clients,

        adjust (\r -> r{playersIDs = IntSet.insert clID (playersIDs r), playersIn = (playersIn r) + 1}) rID $

            adjust (\r -> r{playersIDs = IntSet.delete clID (playersIDs r)}) 0 rooms

        ) joinMsg

    where

        client = clients ! clID

        joinMsg = if rID == 0 then

                AnswerAllOthers ["LOBBY:JOINED", nick client]

            else

                AnswerThisRoom ["JOINED", nick client]

processAction (clID, serverInfo, rnc) (KickClient kickID) =

    liftM2 replaceID (return clID) (processAction (kickID, serverInfo, rnc) $ ByeClient "Kicked")

processAction (clID, serverInfo, rnc) (BanClient banNick) =

    return (clID, serverInfo, rnc)

processAction (clID, serverInfo, rnc) (KickRoomClient kickID) = do

    writeChan (sendChan $ clients ! kickID) ["KICKED"]

    liftM2 replaceID (return clID) (processAction (kickID, serverInfo, rnc) $ RoomRemoveThisClient "kicked")

-}

processAction (AddClient client) = do

    rnc <- gets roomsClients

    si <- gets serverInfo

    io $ do

        ci <- addClient rnc client

        t <- forkIO $ clientRecvLoop (clientSocket client) (coreChan si) ci

        forkIO $ clientSendLoop (clientSocket client) t (coreChan si) (sendChan client) ci

        infoM "Clients" (show ci ++ ": New client. Time: " ++ show (connectTime client))

    processAction $ AnswerClients [sendChan client] ["CONNECTED", "Hedgewars server http://www.hedgewars.org/"]

{-        let newLogins = takeWhile (\(_ , time) -> (connectTime client) `diffUTCTime` time <= 11) $ lastLogins serverInfo

        if False && (isJust $ host client `Prelude.lookup` newLogins) then

            processAction (ci, serverInfo{lastLogins = newLogins}, rnc) $ ByeClient "Reconnected too fast"

            else

            return (ci, serverInfo)

-}

processAction PingAll = do

    rnc <- gets roomsClients

    io (allClientsM rnc) >>= mapM_ (kickTimeouted rnc)

    cis <- io $ allClientsM rnc

    chans <- io $ mapM (client'sM rnc sendChan) cis

    io $ mapM_ (modifyClient rnc (\cl -> cl{pingsQueue = pingsQueue cl + 1})) cis

    processAction $ AnswerClients chans ["PING"]

    where

        kickTimeouted rnc ci = do

            pq <- io $ client'sM rnc pingsQueue ci

            when (pq > 0) $

                withStateT (\as -> as{clientIndex = Just ci}) $

                    processAction (ByeClient "Ping timeout")

processAction (StatsAction) = do

    rnc <- gets roomsClients

    si <- gets serverInfo

    (roomsNum, clientsNum) <- io $ withRoomsAndClients rnc stats

    io $ writeChan (dbQueries si) $ SendStats clientsNum (roomsNum - 1)

    where

          stats irnc = (length $ allRooms irnc, length $ allClients irnc)