module Main where

import Text.PrettyPrint.HughesPJ

import qualified Data.MultiMap as MM

import Data.Maybe

import Data.List

import Data.Char

import qualified Data.Set as Set

data HWProtocol = Command String [CmdParam]

instance Ord HWProtocol where

    (Command a _) `compare` (Command b _) = a `compare` b    

instance Eq HWProtocol where

    (Command a _) == (Command b _) = a == b

data CmdParam = Skip

              | SS

              | LS

              | IntP

              | Many [CmdParam]

data ClientStates = NotConnected

                  | JustConnected

                  | ServerAuth

                  | Lobby

data ParseTree = PTPrefix String [ParseTree]

               | PTCommand String HWProtocol

cmd = Command

cmd1 s p = Command s [p]

cmd2 s p1 p2 = Command s [p1, p2]

cmdParams2str (Command _ p) = "TCmdParam" ++ concatMap f p

    where

    f Skip = ""

    f SS = "S"

    f LS = "L"

    f IntP = "i"

    f (Many p) = ""

cmdParams2handlerType (Command _ p) = "handler_" ++ concatMap f p

    where

    f Skip = "_"

    f SS = "S"

    f LS = "L"

    f IntP = "i"

    f (Many p) = 'M' : concatMap f p

cmdParams2record cmd@(Command _ p) = renderStyle style{lineLength = 80} $ 

    text "type " <> text (cmdParams2str cmd)

    <> text " = record" $+$ nest 4 (

    vcat (map (uncurry f) $ zip [1..] $ filter isRendered p) 

    $+$ text "end;")

    where

    isRendered Skip = False

    isRendered (Many _) = False

    isRendered _ = True

    f n Skip = empty

    f n SS = text "str" <> int n <> text ": shortstring;"

    f n LS = text "str" <> int n <> text ": longstring;"

    f n IntP = text "param" <> int n <> text ": LongInt;"

    f _ (Many _) = empty

commandsDescription = [

        cmd "CONNECTED" [Skip, IntP]

        , cmd1 "NICK" SS

        , cmd1 "PROTO" IntP

        , cmd1 "ASKPASSWORD" SS

        , cmd1 "SERVER_AUTH" SS

        , cmd1 "JOINING" SS

        , cmd1 "TEAM_ACCEPTED" SS

        , cmd1 "HH_NUM" $ Many [SS]

        , cmd1 "TEAM_COLOR" $ Many [SS]

        , cmd1 "TEAM_ACCEPTED" SS

        , cmd1 "BANLIST" $ Many [SS]

        , cmd1 "JOINED" $ Many [SS]

        , cmd1 "LOBBY:JOINED" $ Many [SS]

        , cmd2 "LOBBY:LEFT" SS LS

        , cmd2 "CLIENT_FLAGS" SS $ Many [SS]

        , cmd2 "LEFT" SS $ Many [SS]

        , cmd1 "SERVER_MESSAGE" LS

        , cmd1 "NOTICE" LS

        , cmd1 "WARNING" LS

        , cmd1 "EM" $ Many [LS]

        , cmd1 "PING" $ Many [SS]

        , cmd2 "CHAT" SS LS

        , cmd2 "SERVER_VARS" SS LS

        , cmd2 "BYE" SS LS

        , cmd1 "INFO" $ Many [SS]

        , cmd1 "ROOMS" $ Many [SS]

        , cmd "KICKED" []

        , cmd "RUN_GAME" []

        , cmd "ROUND_FINISHED" []

    ]

unknowncmd = PTPrefix "$" [PTCommand "$" $ Command "__UNKNOWN__" [Many [SS]]]

groupByFirstChar :: [ParseTree] -> [(Char, [ParseTree])]

groupByFirstChar = MM.assocs . MM.fromList . map breakCmd

makePT cmd@(Command n p) = PTCommand n cmd

buildParseTree cmds = [PTPrefix "!" $ (bpt $ map makePT cmds) ++ [unknowncmd]]

    where

        assocs = groupByFirstChar cmds

        subtree = map buildsub assocs

        buildsub (c, cmds) = let st = bpt cmds in if null $ drop 1 st then maybeMerge c st else PTPrefix [c] st

        maybeMerge c cmd@[PTCommand {}] = PTPrefix [c] cmd

        maybeMerge c cmd@[PTPrefix s ss] = PTPrefix (c:s) ss

dumpTree = vcat . map dt

    where

    dt (PTPrefix s st) = text s $$ (nest 1 $ vcat $ map dt st)

    dt _ = empty

pas2 = buildSwitch $ buildParseTree commandsDescription

    where

        buildSwitch cmds = text "case getNextChar of" $$ (nest 4 . vcat $ map buildCase cmds) $$ elsePart

        buildCase (PTCommand {}) = text "#10: <call cmd handler>;"

        buildCase (PTPrefix (s:ss) cmds) = quotes (char s) <> text ": " <> consumePrefix ss (buildSwitch cmds)

        consumePrefix "" = id

        consumePrefix str = (text "consume" <> (parens . quotes $ text str) <> semi $$)

        zeroChar = text "#0: state:= pstDisconnected;"

        elsePart = text "else <unknown cmd> end;"

renderArrays (letters, commands, handlers) = vcat $ punctuate (char '\n') [cmds, l, s, bodies, c, structs]

    where

        maybeQuotes "$" = text "#0"

        maybeQuotes s = if null $ tail s then quotes $ text s else text s

        l = text "const letters: array[0.." <> (int $ length letters - 1) <> text "] of char = "

            <> parens (hsep . punctuate comma $ map maybeQuotes letters) <> semi

        s = text "const commands: array[0.." <> (int $ length commands - 1) <> text "] of integer = "

            <> parens (hsep . punctuate comma $ map text commands) <> semi

        c = text "const handlers: array[0.." <> (int $ length fixedNames - 1) <> text "] of PHandler = "

            <> parens (hsep . punctuate comma $ map (text . (:) '@') handlerTypes) <> semi

        handlerTypes = map cmdParams2handlerType . reverse $ sort commandsDescription

        fixedNames = map fixName handlers

        fixName = map fixChar

        fixChar c | isLetter c = c

                  | otherwise = '_'

        bodies = vcat $ punctuate (char '\n') $ map handlerBody fixedNames

        handlerBody n = text "procedure handler_" <> text n <> semi

            $+$ text "begin" 

            $+$ text "end" <> semi

        cmds = text "type TCmdType = " <> parens (hsep $ punctuate comma $ map ((<>) (text "cmd_") . text) $ reverse fixedNames) <> semi

        structs = vcat (map text . Set.toList . Set.fromList $ map cmdParams2record commandsDescription)

pas = renderArrays $ buildTables $ buildParseTree commandsDescription

    where

        buildTables cmds = let (_, _, _, t1, t2, t3) = foldr walk (0, [0], -10, [], [], [[]]) cmds in (tail t1, tail t2, concat t3)

        walk (PTCommand _ (Command n params)) (lc, s:sh, pc, tbl1, tbl2, (t3:tbl3)) =

            (lc, 1:sh, pc - 1, "#10":tbl1, show pc:tbl2, (n:t3):tbl3)

        walk (PTPrefix prefix cmds) l = lvldown $ foldr fpf (foldr walk (lvlup l) cmds) prefix

        lvlup (lc, sh, pc, tbl1, tbl2, tbl3) = (lc, 0:sh, pc, tbl1, tbl2, []:tbl3)

        lvldown (lc, s1:s2:sh, pc, tbl1, t:tbl2, t31:t32:tbl3) = (lc, s1+s2:sh, pc, tbl1, (if null t32 then "0" else show s1):tbl2, (t31 ++ t32):tbl3)

        fpf c (lc, s:sh, pc, tbl1, tbl2, tbl3) = (lc + 1, s+1:sh, pc, [c]:tbl1, "0":tbl2, tbl3)