{-# LANGUAGE ViewPatterns #-}

import Control.Monad

import Control.Lens

import System.Console.Shell
import System.Console.Shell.ShellMonad
import System.Console.Shell.Backend.Haskeline

import System.Environment.XDG.BaseDir
import System.FilePath
import System.Directory

import Data.Default
import Data.CaseInsensitive (CI)
import qualified Data.CaseInsensitive

import Data.Map.Strict (Map)
import qualified Data.Map.Strict as Map

import Data.Bimap (Bimap)
import qualified Data.Bimap as Bimap

import Data.List

import Data.List
import Data.Maybe

import Data.Function

import Control.Monad.State.Strict

import Sequence.Types
import Sequence.Utils
import Sequence.Formula

import Text.Layout.Table

main :: IO ()
main = do
  historyFile <- getUserCacheFile "sequence" "history"
  createDirectoryIfMissing True $ takeDirectory historyFile
  let
    description = initialShellDescription
                  { historyFile = Just historyFile
                  , prompt = \st -> return $ maybe "" (++ " ") ((evalState ?? st) . toName <$> view tip st) ++ "→ "
                  , beforePrompt = gets stateOutline >>= (\str -> if null str then return () else shellPutStrLn str)
                  , commandStyle = OnlyCommands
                  , shellCommands = [ exitCommand "exit"
                                    , helpCommand "help"
                                    , cmd "entities" listEntities "List all entities"
                                    , cmd "tip" focusTip "Focus the entity at the top of the queue"
                                    , cmd "focus" setFocus "Focus a specific entity"
                                    , cmd "blur" blur "Focus no entity"
                                    , cmd "remove" remove "Remove the focused entity from the queue"
                                    , cmd "factions" listFactions "List all inhabited factions"
                                    , cmd "members" listFaction "List all members of a faction"
                                    , cmd "align" alignEntity "Align the focused entity to a faction – creating it, if necessary"
                                    ]
                  }
  void $ runShell description haskelineBackend (def :: GameState)

stateOutline :: GameState -> String
stateOutline st
  | null pQueue = ""
  | otherwise   = layoutTableToString rowGs (Just ("" : factions, repeat def)) (repeat def) unicodeBoldHeaderS
  where
    factions = map (view faction') $ st ^. inhabitedFactions
    pQueue = st ^. priorityQueue
    protoRows = groupBy ((==) `on` fst) pQueue
    faction id = fromJust $ view eFaction <$> Map.lookup id (st ^. gEntities)
    factionIndex id = fromJust $ elemIndex (view faction' $ faction id) factions
    rowGs = do
      rowGroup'@((seqVal', _):_) <- protoRows
      let
        rowGroup = map snd rowGroup'
        factionColumn i = [evalState ?? st $ toName x | x <- rowGroup, factionIndex x == i ]
      return . colsAllG top $ [show (seqVal' ^. seqVal)] : map factionColumn [0..(length factions - 1)]

-- Query state
listFactions, listEntities :: Sh GameState ()
listFactions = use inhabitedFactions >>= mapM_ (shellPutStrLn . view faction')
listEntities = use (gEntities . to Map.keys) >>= mapM_ (shellPutStrLn <=< toName)

-- Manage faction
listFaction, alignEntity :: Completable Faction -> Sh GameState ()
listFaction = withArg $ \qFaction -> use gEntities >>= mapM_ (shellPutStrLn <=< toName) . Map.keys . Map.filter ((==) qFaction . view eFaction)
alignEntity = withArg $ \nFaction -> withFocus $ \ident -> gEntities %= Map.adjust (set eFaction nFaction) ident

-- Automatic focus
focusTip, blur :: Sh GameState ()
focusTip = gFocus <~ use tip
blur     = gFocus .= Nothing

-- Manual focus
setFocus :: Completable EntityIdentifier -> Sh GameState ()
setFocus = withArg $ \ident -> gFocus .= Just ident

-- Drop information
remove :: Sh GameState ()
remove = withFocus $ \ident -> do
  name <- toName ident
  confirmation <- askBool ("Are you sure you want to remove ‘" ++ name ++ "’?") False
  when confirmation $ do
    gEntities %= Map.delete ident
    gEntityNames %= Bimap.delete ident
    blur