---@class BatRenderState
---@field batBase XyPair
---@field batTip XyPair
---@field batAngleDeg number
---@field batSpeed number

---@class Batting
---@field private Baserunning
---@field state BatRenderState Is updated by checkForHit()
Batting = {}

local SwingBackDeg <const> = 30
local SwingForwardDeg <const> = 170
local OffscreenPos <const> = utils.xy(-999, -999)

---@param baserunning Baserunning
function Batting.new(baserunning)
    return setmetatable({
        baserunning = baserunning,
        state = {
            batAngleDeg = 0,
            batSpeed = 0,
            batTip = OffscreenPos,
            batBase = OffscreenPos,
        },
    }, { __index = Batting })
end

-- TODO? Make the bat angle work more like the throw meter.
-- Would instead constantly drift toward a default value, giving us a little more control,
-- and letting the user find a crank position and direction that works for them

--- Assumes the bat is being held by self.baserunning.batter
--- Mutates self.state for later rendering.
---@param batDeg number
---@param batSpeed number
---@param ball Point3d
---@return XyPair | nil, boolean, number | nil Ball destination or nil if no hit, true only if batter swung, power mult
function Batting:checkForHit(batDeg, batSpeed, ball)
    local batter = self.baserunning.batter
    local isSwinging = batDeg > SwingBackDeg and batDeg < SwingForwardDeg
    local batRadians = math.rad(batDeg)

    local base = batter and utils.xy(batter.x + C.BatterHandPos.x, batter.y + C.BatterHandPos.y) or OffscreenPos
    local tip = utils.xy(base.x + (C.BatLength * math.sin(batRadians)), base.y + (C.BatLength * math.cos(batRadians)))

    self.state.batSpeed = batSpeed
    self.state.batAngleDeg = batDeg
    self.state.batTip = tip
    self.state.batBase = base

    local ballWasHit = batSpeed > 0 and ball.y < 232 and utils.pointOnOrUnderLine(ball, base, tip, C.Screen.H)

    if not ballWasHit then
        return nil, isSwinging
    end

    local ballAngle = batRadians + math.rad(90)
    local mult = math.abs(batSpeed / 15)
    local ballVelX = mult * C.BattingPower * 10 * math.sin(ballAngle)
    local ballVelY = mult * C.BattingPower * 5 * math.cos(ballAngle)
    if ballVelY > 0 then
        ballVelX = ballVelX * -1
        ballVelY = ballVelY * -1
    end

    return utils.xy(ball.x + ballVelX, ball.y + ballVelY), isSwinging, mult
end