{- |
Module testing for properties of creatures, whether they are reloading, etc.
Each function takes a creature, and possibly other parameters, and returns a bool.
Note that if there is a world parameter,
the creature NEED NOT be the same as the creature with that id in the world,
in fact a creature with that id need not exist.
-}
module Dodge.Creature.Test (
    crIsAiming,
    crIsReloading,
    crIsArmouredFrom,
    oneH,
    twists,
    twoFlat,
    crWeaponReady,
    crInAimStance,
    crNearPoint,
    isAnimate,
    crCanShoot,
    crHasTargetLOS,
    crAwayFromPost,
    crHasTarget,
    crStratConMatches,
    crSafeDistFromTarg,
) where

import Control.Lens
import Data.List (find)
import Data.Maybe
import Dodge.Base.Collide
import Dodge.Data.World
import Geometry

crIsReloading :: Creature -> Bool
crIsReloading cr = case cr ^? crInvSel . iselAction of
    Just ReloadAction{} -> True
    _ -> False

crWeaponReady :: Creature -> Bool
crWeaponReady cr = fromMaybe False $ do
    ic <- cr ^? crInv . ix (crSel cr) . itUse . heldConsumption
    return (_laLoaded ic > 0 && _laPrimed ic)

crCanSeeCr :: Creature -> (World, Creature) -> Bool
crCanSeeCr tcr (w, cr) = hasLOS (_crPos cr) (_crPos tcr) w

crIsAiming :: Creature -> Bool
crIsAiming cr = _posture (_crStance cr) == Aiming

crHasTarget :: Creature -> Bool
crHasTarget cr = isJust $ cr ^? crIntention . targetCr . _Just

crHasTargetLOS :: World -> Creature -> Bool
crHasTargetLOS w cr = case cr ^? crIntention . targetCr . _Just of
    Just i -> crCanSeeCr i (w, cr)
    Nothing -> False

crSafeDistFromTarg :: Float -> Creature -> Bool
crSafeDistFromTarg d cr = case cr ^? crIntention . targetCr . _Just of
    Just tcr -> dist (_crPos cr) (_crPos tcr) > d
    Nothing -> True

crStratConMatches :: Strategy -> Creature -> Bool
crStratConMatches strat cr = strat == _apStrategy (_crActionPlan cr)

-- this equality check might be slow...

crAwayFromPost :: Creature -> Bool
crAwayFromPost cr = case find sentinelGoal . _apGoal $ _crActionPlan cr of
    Just (SentinelAt p _) -> dist p (_crPos cr) > 15
    _ -> False
  where
    sentinelGoal (SentinelAt _ _) = True
    sentinelGoal _ = False

crCanShoot :: Creature -> Bool
crCanShoot cr = crIsAiming cr && crWeaponReady cr

crInAimStance :: AimStance -> Creature -> Bool
crInAimStance as cr =
    crIsAiming cr
        && cr ^? crInv . ix (crSel cr) . itUse . heldAim . aimStance == Just as

oneH :: Creature -> Bool
oneH = crInAimStance OneHand

twoFlat :: Creature -> Bool
twoFlat = crInAimStance TwoHandFlat

twists :: Creature -> Bool
twists = crInAimStance TwoHandTwist

-- the use of crOldPos is because the damage position is calculated on the
-- previous frame
-- Not sure if it is a good idea
crIsArmouredFrom :: Point2 -> Creature -> Bool
crIsArmouredFrom = hasFrontArmour

hasFrontArmour :: Point2 -> Creature -> Bool
hasFrontArmour p cr = fromMaybe False $ do
    invid <- cr ^? crEquipment . ix OnChest
    ittype <- cr ^? crInv . ix invid . itType . iyBase
    return $
        EQUIP FRONTARMOUR == ittype
            && p /= _crOldPos cr
            && angleVV (unitVectorAtAngle (_crDir cr + frontarmdirection)) (p -.- _crOldPos cr) < pi / 2
  where
    -- even though angleVV can generate NaN, the comparison seems to deal with it

    frontarmdirection
        | crInAimStance OneHand cr = 0.5
        | crInAimStance TwoHandTwist cr = negate 1
        | otherwise = 0

--crOnSeg :: Point2 -> Point2 -> Creature -> Bool
--crOnSeg p1 p2 cr = circOnSeg p1 p2 (_crPos cr) (_crRad cr)

--crNearSeg :: Float -> Point2 -> Point2 -> Creature -> Bool
--crNearSeg d p1 p2 cr = circOnSeg p1 p2 (_crPos cr) (_crRad cr + d)

crNearPoint :: Float -> Point2 -> Creature -> Bool
crNearPoint d p cr = dist (_crPos cr) p < d + _crRad cr

isAnimate :: Creature -> Bool
{-# INLINE isAnimate #-}
isAnimate cr = case _crActionPlan cr of
    Inanimate -> False
    _ -> True