using System;
namespace Socer;

// Presentation only: follows real expenditure, never writes player stamina.
public sealed class StaminaReadout
{
    readonly float[] previous=new float[22],remaining=new float[22];
    public float[] Fill=new float[22],Opacity=new float[22];
    MatchSimulation match;
    float sampledSeconds=-1;
    public void Update(MatchSimulation m,float dt,bool paused)
    {
        dt=Math.Clamp(dt,0,.1f);
        if(match!=m)
        {
            match=m;sampledSeconds=m.Seconds;Array.Clear(remaining);Array.Clear(Opacity);
            foreach(var p in m.Players)previous[p.Id]=Fill[p.Id]=p.Stamina;
            return;
        }
        bool fresh=m.Seconds!=sampledSeconds;
        foreach(var p in m.Players)
        {
            if(fresh && previous[p.Id]-p.Stamina>.000001f)remaining[p.Id]=.75f;
            if(fresh)previous[p.Id]=p.Stamina;
            if(!paused)remaining[p.Id]=Math.Max(0,remaining[p.Id]-dt);
            Fill[p.Id]+=(p.Stamina-Fill[p.Id])*(1-MathF.Exp(-dt*12));
            Opacity[p.Id]=p.SentOff?0:Math.Clamp(remaining[p.Id]/.3f,0,1);
        }
        sampledSeconds=m.Seconds;
    }
}