## Standalone radar lock module for Robocode Tank Royale (1v1).
## No bot-specific imports — takes plain floats, returns radarTurnRate.
##
## Tank Royale radar uses standard math convention: 0° = east, CCW positive.
## Angles are in degrees.

import std/math

const
  MaxRadarTurn* = 45.0
  DefaultOvershootDeg* = 5.0

var overShootDeg* = DefaultOvershootDeg

proc init*() =
  ## Reset module to defaults.
  ## In your bot's constructor set:
  ##   adjustRadarForBodyTurn = true
  ##   adjustRadarForGunTurn  = true
  overShootDeg = DefaultOvershootDeg

proc normalizeRelative(angle: float64): float64 {.inline.} =
  result = angle mod 360.0
  if result >= 180.0: result -= 360.0
  elif result < -180.0: result += 360.0

proc doRadar*(currentRadarHeading, enemyBearing: float64): float64 =
  ## Returns radarTurnRate (degrees/tick, positive = clockwise).
  ##
  ## currentRadarHeading: current radar direction in degrees (0=east, CCW+).
  ## enemyBearing:        absolute bearing to enemy in same coordinate system.
  ##
  ## Handles angle wrapping, clamps to [-45, +45], adds overshoot sweep.
  var turn = normalizeRelative(enemyBearing - currentRadarHeading)
  # Add overshoot in the same direction as the turn to maintain lock
  if turn < 0.0: turn -= overShootDeg
  else:          turn += overShootDeg
  result = turn.clamp(-MaxRadarTurn, MaxRadarTurn)