## Gun selector — picks best gun×power, computes aim angle, gates firing.
## Fires highest power with acceptable hit rate when gun is aimed within
## threshold and gunHeat == 0.

import std/math
import gun_interface
import virtual_bullets

const AimThresholdDeg* = 2.0  ## max angle error to fire; ponytail: tune per bot

proc aimAngle*(selfX, selfY, targetX, targetY: float): float =
  ## Absolute bearing in degrees (0=East, CCW+) toward (targetX, targetY).
  result = radToDeg(arctan2(targetY - selfY, targetX - selfX))

proc shouldFire*(currentGunDir, targetAngle, gunHeat: float): bool =
  ## Returns true when gun is close enough and cool enough to fire.
  var delta = (targetAngle - currentGunDir) mod 360.0
  if delta > 180.0:  delta -= 360.0
  elif delta < -180.0: delta += 360.0
  abs(delta) <= AimThresholdDeg and gunHeat <= 0.0

proc selectShot*(t: VirtualTracker, targetId: int = -1): (GunId, int, float) =
  ## Returns (gunId, powerBinIdx, power) — the shot to take this tick.
  ## Pass targetId to pick the best gun for that specific enemy.
  let gunId = t.bestGun(targetId)
  let (binIdx, power) = t.bestPower(gunId, targetId)
  result = (gunId, binIdx, power)