{-# LANGUAGE LambdaCase #-}
module Dodge.Item.HeldOffset (
    turretItemOffset,
    twoFlatHRot,
    heldItemOffset,
    heldItemRelativeOrient,
    heldItemOrient2D,
) where

import Dodge.Data.AimStance
import Dodge.Item.AimStance
import qualified Quaternion as Q
import Dodge.Data.Creature
import Dodge.Data.Machine
import Geometry
import LensHelp

turretItemOffset :: Item -> Turret -> Machine -> Point3 -> Point3
turretItemOffset it tu mc =
    rotate3 (_tuDir tu - _mcDir mc) . (+.+.+ V3 0 0 shoulderHeight)
        . transToHandle it

transToHandle :: Item -> Point3 -> Point3
transToHandle itm = (-.-.- V3 x y 0)
  where
    V2 x y = handlePos itm

heldItemOrient2D :: Item -> Creature -> Point2 -> Float -> (Point2, Float)
heldItemOrient2D itm cr p a = (V2 x y, argV . Q.qToV2 $ q )
  where
    (V3 x y _,q) = heldItemRelativeOrient itm cr (p `v2z` 0, Q.axisAngle (V3 0 0 1) a)

heldItemRelativeOrient 
    :: Item -> Creature -> (Point3, Q.Quaternion Float) -> (Point3, Q.Quaternion Float)
heldItemRelativeOrient itm cr (p,q)
    | Aiming {} <- _posture (_crStance cr) =
        (p + aimingWeaponZeroPos cr itm `v2z` shoulderHeight, Q.qID * q)
    |  TwoHandFlat <- aStance itm = 
        ( V3 (_crRad cr) 0 handD + rotate3 (twoFlatHRot cr) (transToHandle itm p)
        , Q.axisAngle (V3 0 0 1) (twoFlatHRot cr) * q
        )
    |  OneHand <- aStance itm = 
            ( V3 (_crRad cr * 0.7 + handPos) (_crRad cr * negate 0.7) handD
                + transToHandle itm p
            , Q.qID * q
            )
    | otherwise = 
        ( V3 (_crRad cr) 0 handD 
            + rotate3 (strideRot cr + 1.2) (V3 (-8) 0 0 + transToHandle itm p)
        , Q.axisAngle (V3 0 0 1) (strideRot cr + 1.2) * q
        )
  where
    handD = 15
    handPos = case cr ^? crStance . carriage of
        Just (Walking x LeftForward) -> f x * 50 -2
        _ -> 0 - 2
    f i = 0.1 * fromIntegral (sLen - i) / fromIntegral sLen
    sLen = _strideLength $ _crStance cr

aimingWeaponZeroPos :: Creature -> Item -> Point2
aimingWeaponZeroPos cr it = aimStanceHandlePos cr it - handlePos it

-- the position of a weapon handle
aimStanceHandlePos :: Creature -> Item -> Point2
aimStanceHandlePos _ it = case aStance it of
    TwoHandUnder -> V2 (-2) 0
    TwoHandOver -> V2 (-7) 0
    OneHand -> V2 10 (-2)
    TwoHandFlat -> V2 10 0

heldItemOffset :: Item -> Creature -> Point3 -> Point3
heldItemOffset itm cr p = fst (heldItemRelativeOrient itm cr (p,Q.qID))

shoulderHeight :: Float
shoulderHeight = 18

strideRot :: Creature -> Float
strideRot cr = case cr ^? crStance . carriage of
    Just (Walking x LeftForward) -> f x
    Just (Walking x RightForward) -> - f x
    _ -> 0
  where
    f i = 0.1 * fromIntegral (sLen - i) / fromIntegral sLen
    sLen = _strideLength $ _crStance cr

twoFlatHRot :: Creature -> Float
twoFlatHRot = (2 *) . strideRot

handlePos :: Item -> Point2
handlePos itm = case itm ^. itType of
    HELD hit -> heldHandlePos hit
    _ -> 0

heldHandlePos :: HeldItemType -> Point2
heldHandlePos = \case
    BANGSTICK{} -> V2 3 0
    REWINDER -> V2 3 0
    TIMESTOPPER -> V2 3 0
    TIMESCROLLER -> V2 3 0
    PISTOL -> V2 3 0
    MACHINEPISTOL -> V2 3 0
    AUTOPISTOL -> V2 3 0
    SMG -> V2 3 0
    BANGCONE -> V2 3 0
    BLUNDERBUSS -> V2 3 0
    GRAPECANNON{} -> V2 3 0
    MINIGUNX{} -> V2 3 0
    VOLLEYGUN{} -> V2 3 0
    RIFLE -> V2 3 0
    ALTERIFLE -> V2 3 0
    AUTORIFLE -> V2 3 0
    BURSTRIFLE -> V2 3 0
    BANGROD -> V2 3 0
    ELEPHANTGUN -> V2 3 0
    AMR -> V2 3 0
    AUTOAMR -> V2 3 0
    SNIPERRIFLE -> V2 3 0
    FLAMESPITTER -> V2 3 0
    FLAMETHROWER -> V2 3 0
    FLAMETORRENT -> V2 3 0
    FLAMEWALL -> V2 3 0
    BLOWTORCH -> V2 3 0
    SPARKGUN -> V2 3 0
    TESLAGUN -> V2 3 0
    LASER -> V2 3 0
    TRACTORGUN -> V2 3 0
    RLAUNCHER -> V2 3 0
    RLAUNCHERX{} -> V2 3 0
    GLAUNCHER -> V2 3 0
    POISONSPRAYER -> V2 3 0
    SHATTERGUN -> V2 3 0
    TORCH -> V2 3 0
    FLATSHIELD -> V2 3 0
    KEYCARD {} -> V2 3 0
    BLINKER -> V2 3 0
    BLINKERUNSAFE -> V2 3 0