{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE QuasiQuotes #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE ViewPatterns #-}

-- |
-- SPDX-License-Identifier: BSD-3-Clause
--
-- Application state for the @brick@-based Swarm TUI.
module Swarm.TUI.Model (
  -- * Custom UI label types
  -- $uilabel
  AppEvent (..),
  WebCommand (..),
  FocusablePanel (..),
  Name (..),

  -- * Menus and dialogs
  ModalType (..),
  ScenarioOutcome (..),
  Button (..),
  ButtonAction (..),
  Modal (..),
  modalType,
  modalDialog,
  MainMenuEntry (..),
  mainMenu,
  Menu (..),
  _NewGameMenu,
  mkScenarioList,
  mkNewGameMenu,

  -- * UI state

  -- ** REPL
  REPLHistItem (..),
  replItemText,
  isREPLEntry,
  getREPLEntry,
  REPLHistory,
  replIndex,
  replLength,
  replSeq,
  newREPLHistory,
  addREPLItem,
  restartREPLHistory,
  getLatestREPLHistoryItems,
  moveReplHistIndex,
  getCurrentItemText,
  replIndexIsAtInput,
  TimeDir (..),

  -- ** Prompt utils
  REPLPrompt (..),
  removeEntry,

  -- ** Inventory
  InventoryListEntry (..),
  _Separator,
  _InventoryEntry,
  _EquippedEntry,

  -- *** REPL Panel Model
  REPLState,
  ReplControlMode (..),
  replPromptType,
  replPromptEditor,
  replPromptText,
  replValid,
  replLast,
  replType,
  replControlMode,
  replHistory,
  newREPLEditor,

  -- ** Updating
  populateInventoryList,
  infoScroll,
  modalScroll,
  replScroll,

  -- * Runtime state
  RuntimeState,
  webPort,
  upstreamRelease,
  eventLog,
  worlds,
  scenarios,
  stdEntityMap,
  stdRecipes,
  appData,
  nameParts,

  -- ** Utility
  logEvent,
  mkGameStateConfig,

  -- * App state
  AppState (AppState),
  gameState,
  uiState,
  runtimeState,

  -- ** Initialization
  AppOpts (..),
  defaultAppOpts,
  Seed,

  -- *** Re-exported types used in options
  ColorMode (..),

  -- ** Utility
  topContext,
  focusedItem,
  focusedEntity,
  nextScenario,
  initRuntimeState,
) where

import Brick
import Brick.Widgets.List qualified as BL
import Control.Effect.Accum
import Control.Effect.Lift
import Control.Effect.Throw
import Control.Lens hiding (from, (<.>))
import Control.Monad ((>=>))
import Control.Monad.State (MonadState)
import Data.List (findIndex)
import Data.List.NonEmpty (NonEmpty (..))
import Data.Map (Map)
import Data.Maybe (fromMaybe)
import Data.Sequence (Seq)
import Data.Text (Text)
import Data.Vector qualified as V
import GitHash (GitInfo)
import Graphics.Vty (ColorMode (..))
import Network.Wai.Handler.Warp (Port)
import Swarm.Game.CESK (TickNumber (..))
import Swarm.Game.Entity as E
import Swarm.Game.Failure
import Swarm.Game.Recipe (Recipe, loadRecipes)
import Swarm.Game.ResourceLoading (NameGenerator, initNameGenerator, readAppData)
import Swarm.Game.Robot
import Swarm.Game.Scenario.Status
import Swarm.Game.ScenarioInfo (ScenarioCollection, loadScenarios, _SISingle)
import Swarm.Game.State
import Swarm.Game.World.Load (loadWorlds)
import Swarm.Game.World.Typecheck (WorldMap)
import Swarm.Log
import Swarm.TUI.Inventory.Sorting
import Swarm.TUI.Model.Menu
import Swarm.TUI.Model.Name
import Swarm.TUI.Model.Repl
import Swarm.TUI.Model.UI
import Swarm.Util.Lens (makeLensesNoSigs)
import Swarm.Version (NewReleaseFailure (NoMainUpstreamRelease))
import Text.Fuzzy qualified as Fuzzy

------------------------------------------------------------
-- Custom UI label types
------------------------------------------------------------

-- $uilabel These types are used as parameters to various @brick@
-- types.

newtype WebCommand = RunWebCode Text
  deriving (Show)

-- | 'Swarm.TUI.Model.AppEvent' represents a type for custom event types our app can
--   receive. The primary custom event 'Frame' is sent by a separate thread as fast as
--   it can, telling the TUI to render a new frame.
data AppEvent
  = Frame
  | Web WebCommand
  | UpstreamVersion (Either NewReleaseFailure String)
  deriving (Show)

infoScroll :: ViewportScroll Name
infoScroll = viewportScroll InfoViewport

modalScroll :: ViewportScroll Name
modalScroll = viewportScroll ModalViewport

replScroll :: ViewportScroll Name
replScroll = viewportScroll REPLViewport

-- ----------------------------------------------------------------------------
--                                Runtime state                              --
-- ----------------------------------------------------------------------------

data RuntimeState = RuntimeState
  { _webPort :: Maybe Port
  , _upstreamRelease :: Either NewReleaseFailure String
  , _eventLog :: Notifications LogEntry
  , _worlds :: WorldMap
  , _scenarios :: ScenarioCollection
  , _stdEntityMap :: EntityMap
  , _stdRecipes :: [Recipe Entity]
  , _appData :: Map Text Text
  , _nameParts :: NameGenerator
  }

initRuntimeState ::
  ( Has (Throw SystemFailure) sig m
  , Has (Accum (Seq SystemFailure)) sig m
  , Has (Lift IO) sig m
  ) =>
  m RuntimeState
initRuntimeState = do
  entities <- loadEntities
  recipes <- loadRecipes entities
  worlds <- loadWorlds entities
  scenarios <- loadScenarios entities worlds
  appDataMap <- readAppData
  nameGen <- initNameGenerator appDataMap
  return $
    RuntimeState
      { _webPort = Nothing
      , _upstreamRelease = Left (NoMainUpstreamRelease [])
      , _eventLog = mempty
      , _worlds = worlds
      , _scenarios = scenarios
      , _stdEntityMap = entities
      , _stdRecipes = recipes
      , _appData = appDataMap
      , _nameParts = nameGen
      }

makeLensesNoSigs ''RuntimeState

-- | The port on which the HTTP debug service is running.
webPort :: Lens' RuntimeState (Maybe Port)

-- | The upstream release version.
upstreamRelease :: Lens' RuntimeState (Either NewReleaseFailure String)

-- | A log of runtime events.
--
-- This logging is separate from the logging done during game-play.
-- If some error happens before a game is even selected, this is the
-- place to log it.
eventLog :: Lens' RuntimeState (Notifications LogEntry)

-- | A collection of typechecked world DSL terms that are available to
--   be used in scenario definitions.
worlds :: Lens' RuntimeState WorldMap

-- | The collection of scenarios that comes with the game.
scenarios :: Lens' RuntimeState ScenarioCollection

-- | The standard entity map loaded from disk.  Individual scenarios
--   may define additional entities which will get added to this map
--   when loading the scenario.
stdEntityMap :: Lens' RuntimeState EntityMap

-- | The standard list of recipes loaded from disk.  Individual scenarios
--   may define additional recipes which will get added to this list
--   when loading the scenario.
stdRecipes :: Lens' RuntimeState [Recipe Entity]

-- | Free-form data loaded from the @data@ directory, for things like
--   the logo, about page, tutorial story, etc.
appData :: Lens' RuntimeState (Map Text Text)

-- | Lists of words/adjectives for use in building random robot names.
nameParts :: Lens' RuntimeState NameGenerator

--------------------------------------------------
-- Utility

-- | Simply log to the runtime event log.
logEvent :: LogSource -> Severity -> Text -> Text -> Notifications LogEntry -> Notifications LogEntry
logEvent src sev who msg el =
  el
    & notificationsCount %~ succ
    & notificationsContent %~ (l :)
 where
  l = LogEntry (TickNumber 0) src sev who msg

-- | Create a 'GameStateConfig' record from the 'RuntimeState'.
mkGameStateConfig :: RuntimeState -> GameStateConfig
mkGameStateConfig rs =
  GameStateConfig
    { initNameParts = rs ^. nameParts
    , initEntities = rs ^. stdEntityMap
    , initRecipes = rs ^. stdRecipes
    , initWorldMap = rs ^. worlds
    }

-- ----------------------------------------------------------------------------
--                                   APPSTATE                                --
-- ----------------------------------------------------------------------------

-- | The 'AppState' just stores together the other states.
--
-- This is so you can use a smaller state when e.g. writing some game logic
-- or updating the UI. Also consider that GameState can change when loading
-- a new scenario - if the state should persist games, use RuntimeState.
data AppState = AppState
  { _gameState :: GameState
  , _uiState :: UIState
  , _runtimeState :: RuntimeState
  }

--------------------------------------------------
-- Lenses for AppState

makeLensesNoSigs ''AppState

-- | The 'GameState' record.
gameState :: Lens' AppState GameState

-- | The 'UIState' record.
uiState :: Lens' AppState UIState

-- | The 'RuntimeState' record
runtimeState :: Lens' AppState RuntimeState

--------------------------------------------------
-- Utility functions

-- | Get the currently focused 'InventoryListEntry' from the robot
--   info panel (if any).
focusedItem :: AppState -> Maybe InventoryListEntry
focusedItem s = do
  list <- s ^? uiState . uiInventory . _Just . _2
  (_, entry) <- BL.listSelectedElement list
  return entry

-- | Get the currently focused entity from the robot info panel (if
--   any).  This is just like 'focusedItem' but forgets the
--   distinction between plain inventory items and equipped devices.
focusedEntity :: AppState -> Maybe Entity
focusedEntity =
  focusedItem >=> \case
    Separator _ -> Nothing
    InventoryEntry _ e -> Just e
    EquippedEntry e -> Just e

------------------------------------------------------------
-- Functions for updating the UI state
------------------------------------------------------------

-- | Given the focused robot, populate the UI inventory list in the info
--   panel with information about its inventory.
populateInventoryList :: (MonadState UIState m) => Maybe Robot -> m ()
populateInventoryList Nothing = uiInventory .= Nothing
populateInventoryList (Just r) = do
  mList <- preuse (uiInventory . _Just . _2)
  showZero <- use uiShowZero
  sortOptions <- use uiInventorySort
  search <- use uiInventorySearch
  let mkInvEntry (n, e) = InventoryEntry n e
      mkInstEntry (_, e) = EquippedEntry e
      itemList isInventoryDisplay mk label =
        (\case [] -> []; xs -> Separator label : xs)
          . map mk
          . sortInventory sortOptions
          . filter ((&&) <$> matchesSearch <*> shouldDisplay)
          . elems
       where
        -- Display items if we have a positive number of them, or they
        -- aren't an equipped device.  In other words we don't need to
        -- display equipped devices twice unless we actually have some
        -- in our inventory in addition to being equipped.
        shouldDisplay (n, e) =
          n > 0
            || isInventoryDisplay
              && showZero
              && not ((r ^. equippedDevices) `E.contains` e)

      matchesSearch :: (Count, Entity) -> Bool
      matchesSearch (_, e) = maybe (const True) Fuzzy.test search (e ^. E.entityName)

      items =
        (r ^. robotInventory . to (itemList True mkInvEntry "Compendium"))
          ++ (r ^. equippedDevices . to (itemList False mkInstEntry "Equipped devices"))

      -- Attempt to keep the selected element steady.
      sel = mList >>= BL.listSelectedElement -- Get the currently selected element+index.
      idx = case sel of
        -- If there is no currently selected element, just focus on
        -- index 1 (not 0, to avoid the separator).
        Nothing -> 1
        -- Otherwise, try to find the same entry in the list;
        -- if it's not there, keep the index the same.
        Just (selIdx, InventoryEntry _ e) ->
          fromMaybe selIdx (findIndex ((== Just e) . preview (_InventoryEntry . _2)) items)
        Just (selIdx, EquippedEntry e) ->
          fromMaybe selIdx (findIndex ((== Just e) . preview _EquippedEntry) items)
        Just (selIdx, _) -> selIdx

      -- Create the new list, focused at the desired index.
      lst = BL.listMoveTo idx $ BL.list InventoryList (V.fromList items) 1

  -- Finally, populate the newly created list in the UI, and remember
  -- the hash of the current robot.
  uiInventory .= Just (r ^. inventoryHash, lst)

------------------------------------------------------------
-- App state (= UI state + game state) initialization
------------------------------------------------------------

-- | Command-line options for configuring the app.
data AppOpts = AppOpts
  { userSeed :: Maybe Seed
  -- ^ Explicit seed chosen by the user.
  , userScenario :: Maybe FilePath
  -- ^ Scenario the user wants to play.
  , scriptToRun :: Maybe FilePath
  -- ^ Code to be run on base.
  , autoPlay :: Bool
  -- ^ Automatically run the solution defined in the scenario file
  , speed :: Int
  -- ^ Initial game speed (logarithm)
  , cheatMode :: Bool
  -- ^ Should cheat mode be enabled?
  , colorMode :: Maybe ColorMode
  -- ^ What colour mode should be used?
  , userWebPort :: Maybe Port
  -- ^ Explicit port on which to run the web API
  , repoGitInfo :: Maybe GitInfo
  -- ^ Information about the Git repository (not present in release).
  }

-- | A default/empty 'AppOpts' record.
defaultAppOpts :: AppOpts
defaultAppOpts =
  AppOpts
    { userSeed = Nothing
    , userScenario = Nothing
    , scriptToRun = Nothing
    , autoPlay = False
    , speed = defaultInitLgTicksPerSecond
    , cheatMode = False
    , colorMode = Nothing
    , userWebPort = Nothing
    , repoGitInfo = Nothing
    }

-- | Extract the scenario which would come next in the menu from the
--   currently selected scenario (if any).  Can return @Nothing@ if
--   either we are not in the @NewGameMenu@, or the current scenario
--   is the last among its siblings.
nextScenario :: Menu -> Maybe ScenarioInfoPair
nextScenario = \case
  NewGameMenu (curMenu :| _) ->
    let nextMenuList = BL.listMoveDown curMenu
        isLastScenario = BL.listSelected curMenu == Just (length (BL.listElements curMenu) - 1)
     in if isLastScenario
          then Nothing
          else BL.listSelectedElement nextMenuList >>= preview _SISingle . snd
  _ -> Nothing

-- | Context for the REPL commands to execute in. Contains the base
--   robot context plus the `it` variable that refer to the previously
--   computed values. (Note that `it{n}` variables are set in the
--   base robot context; we only set `it` here because it's so transient)
topContext :: AppState -> RobotContext
topContext s = ctxPossiblyWithIt
 where
  ctx = fromMaybe emptyRobotContext $ s ^? gameState . baseRobot . robotContext

  ctxPossiblyWithIt = case s ^. gameState . gameControls . replStatus of
    REPLDone (Just p) -> ctx & at "it" ?~ p
    _ -> ctx