using System;
using Goo.Animation;

namespace Goo.FpsUI;

// Crosshair spread logic: a spring 0..1 settling toward a sustained target (movement) with
// transient kicks on fire. The view reads CurrentGap. Engine-free.
public sealed class CrosshairModel
{
    public float Gap         = 6f;   // base center gap in px (still, no spread)
    public float SpreadScale = 14f;  // px added at full spread (0 = fixed-gap crosshair)

    SpringFloat _spread = new( 0f, 12f, 0.7f );  // 0..1 spread amount

    public float Spread     => Math.Clamp( _spread.Current, 0f, 1.5f ); // animated spread 0..1
    public float CurrentGap => Gap + Spread * SpreadScale;              // gap the view draws with

    public void SetSpread( float t ) => _spread.Target = Math.Clamp( t, 0f, 1f ); // sustained (e.g. while moving)
    public void Fire() => _spread.Current = MathF.Min( 1.5f, _spread.Current + 0.5f ); // transient kick

    public bool Tick( float dt ) => _spread.Tick( dt );
}