using Unity.Mathematics;

namespace ProjectM.Client
{
    /// <summary>07-21 G4 (review wf_98bf1268) — pure co-op saturation-budget math (no ECS; unit-tested like
    /// <c>HudVisualMath</c>, the Client-side presentation-math precedent). Maps a live on-screen enemy count to
    /// the ALLY-FX degradation scale: 1 at &lt;= start, linear down to <paramref name="floor"/> at &gt;= full.
    /// Enemy telegraphs never ride this (guidelines G4: they never degrade); local-player FX never ride this.
    /// Note: <c>EnemyMarkerSystem</c>'s pip fade equals <c>AllyScale(count, start, 2*start, floor)</c> — a later
    /// pass can retrofit it onto this helper.</summary>
    public static class SaturationMath
    {
        /// <summary>1 at enemies &lt;= start; linear to <paramref name="floor"/> at enemies &gt;= full; clamped.
        /// Degenerate inputs (full &lt;= start) snap straight to floor once past start.</summary>
        public static float AllyScale(int enemies, int start, int full, float floor)
        {
            floor = math.clamp(floor, 0f, 1f);
            if (enemies <= start) return 1f;
            if (full <= start) return floor;
            float t = math.saturate((enemies - start) / (float)(full - start));
            return math.lerp(1f, floor, t);
        }
    }
}