## Regression test: radar lock must hold on a stationary target.
## Run: nim c -r tests/test_radar_lock.nim

import std/[math, strformat]
import PPO_Bot/enemy_tracker

template check(cond: bool, msg: string) =
  if not cond:
    quit("FAIL: " & msg, 1)

# Bot at arena center; stationary enemy due north (same x, higher y).
# Tank Royale: y increases northward.
# Radar uses math convention (0°=east, CCW+); north = 90° in that system.

let botX = 400.0
let botY = 300.0
let enemyX = 400.0   # same x → dx = 0
let enemyY = 500.0   # north of bot → dy > 0
let trueBearing = 90.0  # north in math convention (0=east, CCW+)

# Radar starts pointing at the enemy (radarDirection = 90°, due north in math convention).
var radarDir = 90.0

var tracker = initEnemyTracker()
# Prime with contact at the known position
tracker.update(enemyX, enemyY, 0.0, 0.0, 100.0)

echo "Tick | radarDir | trueBearing | bearingErr"
for tick in 1 .. 20:
  let rate = tracker.getRadarTurnRate(botX, botY, 0.0, radarDir)
  radarDir = (radarDir + rate + 360.0) mod 360.0

  # Simulate a successful scan every tick (enemy is stationary)
  tracker.update(enemyX, enemyY, 0.0, 0.0, 100.0)

  # Bearing error: signed difference, wrapped to [-180, 180]
  let err = ((radarDir - trueBearing) + 540.0) mod 360.0 - 180.0
  echo &"  {tick:2d} | {radarDir:8.3f}° | {trueBearing:8.3f}° | {err:+.3f}°"

  check abs(err) <= 15.0, &"tick {tick}: radar {radarDir:.1f}° drifted > 15° from target {trueBearing:.1f}°"

echo "All radar lock tests passed"