russel-norvig-ai-problems/chapter2/cleaner.hs

84 lines
2.6 KiB
Haskell

{-# LANGUAGE FlexibleContexts, TemplateHaskell #-}
module AI.Vacuum.Cleaner where
import AI.Vacuum.Grid
import qualified Data.Map as M
import Control.Monad.State
import Prelude hiding (id, (.))
import Control.Category
import Data.Maybe (isJust, isNothing, fromJust)
import Data.Lens.Common
import Data.Lens.Template
data Percept = TouchSensor | PhotoSensor | InfraredSensor deriving (Eq, Ord, Show)
type Percepts = [Percept]
type PerceptsHistory = [Percepts]
data Action = GoForward | TurnRight | TurnLeft | SuckDirt | TurnOff deriving (Eq, Show)
data CleanerState = On | Off deriving (Eq, Show)
type Score = Int
data Cleaner =
Cleaner {
_state :: CleanerState,
_cell :: Cell,
_direction :: Direction,
_path :: [Point],
_perceptsHist :: PerceptsHistory,
_actionHist :: [Action],
_score :: Score
} deriving (Show)
makeLenses [''Cleaner]
createCleaner :: Cell -> Direction -> Cleaner
createCleaner cell dir = Cleaner On cell dir [cell^.point] [] [] 0
setPercepts percepts = perceptsHist ^%= (percepts :)
turnRight :: (MonadState Grid m) => Cleaner -> m Cleaner
turnRight = return . (direction ^%= right) . (setPercepts [])
turnLeft :: (MonadState Grid m) => Cleaner -> m Cleaner
turnLeft = return . (direction ^%= left) . (setPercepts [])
moveForward :: (MonadState Grid m) => Cleaner -> m Cleaner
moveForward cleaner = do
grid <- get
return .
case forwardCell (cleaner^.cell) (cleaner^.direction) grid of
Nothing -> setPercepts [TouchSensor]
Just nextCell@(Cell nextPoint nextCellType) ->
let setNextCellPoint = (cell ^= nextCell) . (path ^%= (nextPoint :)) in
case nextCellType of
Empty -> setNextCellPoint . (setPercepts [])
Furniture -> setPercepts [TouchSensor]
Dirt -> setNextCellPoint . (setPercepts [PhotoSensor])
Home -> setNextCellPoint . (setPercepts [InfraredSensor])
$ cleaner
suckDirt :: (MonadState Grid m) => Cleaner -> m Cleaner
suckDirt cleaner = do
let point' = (cleaner^.cell)^.point
grid <- get
put $ M.insert point' (Cell point' Empty) grid
return cleaner
doAction :: (MonadState Grid m) => Action -> Cleaner -> m Cleaner
doAction action cleaner = do
case action of
GoForward -> moveForward
TurnRight -> turnRight
TurnLeft -> turnLeft
SuckDirt ->
(if cellType' == Dirt then suckDirt . (score ^%= (+ 100)) else return)
. (setPercepts [])
TurnOff ->
return . (state ^= Off) . (setPercepts [])
. (if cellType' == Home then id else score ^%= (subtract 1000))
. (score ^%= subtract 1)
. (actionHist ^%= (action :))
$ cleaner
where
cellType' = (cleaner^.cell)^.cellType