using System;
using System.Collections.Generic;

namespace Socer;

// Timing brief: physical contact peaks on contact, glints end at .18 s, grass
// settles by .60 s. Ordinary ball wake spans .10–.25 s of actual sampled flight.
// No camera-facing rings, random clocks or match-state changes are involved.
public static class FootballMatchEffects
{
    public readonly record struct FlightStroke(bool Visible,Point A,float ZA,Point B,float ZB,
        float Width,string Color,float Opacity);
    public static FlightStroke Flight(IReadOnlyList<FlightMark> trail,int index,Point ball,float height,
        float speed,bool free,UniqueSkill skill,int grade,LegendaryAbility legendary)
    {
        if(!free || speed<=9 || index<0 || index>=trail.Count)return default;
        bool special=skill!=UniqueSkill.None || legendary!=LegendaryAbility.None;
        int visible=special?11:speed>23?7:speed>15?5:3;
        int first=Math.Max(0,trail.Count-visible);
        if(index<first)return default;
        var a=trail[index];
        var b=index+1<trail.Count?trail[index+1]:new FlightMark{Position=ball,Height=height};
        float horizontal=(b.Position-a.Position).Length,dz=b.Height-a.Height;
        float length=MathF.Sqrt(horizontal*horizontal+dz*dz);
        // A restart, camera preview or seek must never draw a bridge across the pitch.
        if(length<.018f || length>3.2f)return default;
        float freshness=(index-first+1f)/Math.Max(1,trail.Count-first);
        float taper=freshness*freshness*(3-2*freshness);
        float width=(.008f+(special?.092f:.050f)*taper)*Math.Clamp(speed/23,.55f,1.12f);
        string color=skill switch
        {
            UniqueSkill.CurveComet=>freshness>.65f?"#ffe6a0":"#b68cd2",
            UniqueSkill.PowerDrive or UniqueSkill.AerialFinisher=>"#efc687",
            UniqueSkill.Sniper=>"#b8d2e8",
            UniqueSkill.ThreadNeedle=>"#a4d7b7",
            UniqueSkill.LongDistributor or UniqueSkill.KeeperDistributor=>"#a7dce0",
            _=>"#e0e6c8"
        };
        if(special && grade==2)width*=1.08f;
        if(legendary!=LegendaryAbility.None)color=LegendaryVisuals.BallColor(legendary,index);
        float opacity=(special?.28f:.12f)+(special?.46f:.36f)*taper;
        return new(true,a.Position,Math.Max(.11f,a.Height),b.Position,Math.Max(.11f,b.Height),width,color,opacity);
    }
}