using Unity.Mathematics;

namespace ProjectM.Simulation
{
    /// <summary>
    /// Pure, deterministic wave-size math — no RNG state, no wall-clock — so a wave is reproducible across
    /// restarts/saves and EditMode-unit-testable without an ECS world (mirrors <see cref="EnemyAIMath"/>).
    ///
    /// HISTORY (2026-08-07 audit purge): this class used to carry a 4-kind weighted composition
    /// (Grunt/Charger/Spitter/Swarmer) driven by a MixBands struct. The Charger/Spitter/Swarmer authoring
    /// components were on ZERO prefabs, so LungeState/SpitterState/SwarmerTag were never baked and every
    /// branch of that math resolved to Grunt at runtime — the escalation curve was inert while 734 lines of
    /// green tests certified it. The composition layer was deleted; the LANTERN bestiary (Drowner, Grindylow,
    /// Wrecker, Wisp-Choir) will reintroduce variety through the CreatureKit path, not through this file.
    /// Recover the old version from git if the weighted-slot model is wanted again.
    /// </summary>
    public static class ZoneEnemyMath
    {
        /// <summary>The single enemy kind. Directors index a per-Kind prefab buffer by this byte; kept as a
        /// byte (not an enum) because <c>EnemyAISystem</c> is Bursted and cross-assembly enums trip Burst.</summary>
        public const byte KindGrunt = 0;

        /// <summary>
        /// Total enemies in this wave: <paramref name="baseCount"/> plus one extra per epoch beyond the first
        /// (a gentle ramp). Lower-bounded at 1 so an occupied arena always has a fight. <paramref name="epoch"/>
        /// is the monotonic wave counter (&gt;=1 in practice). Pure integer math; Burst-safe.
        /// </summary>
        public static int WaveSize(int epoch, int baseCount)
        {
            int e = math.max(1, epoch);
            return math.max(1, math.max(0, baseCount) + (e - 1));
        }
    }
}