using System;
using System.Collections.Generic;
namespace Socer;
public sealed partial class MatchSimulation
{
    void RegisterChallengeImpact(Footballer offender,Footballer victim,bool slide)
    {
        var direction=(victim.Position-offender.Position).Unit;
        offender.ImpactAt=Seconds;offender.ImpactUntil=Seconds+(slide?.85f:.48f);
        offender.ImpactSlide=slide;offender.ImpactDirection=direction;
        offender.ImpactPoint=victim.Position-direction*.14f;
        offender.ImpactVelocity=slide?direction*Math.Clamp(offender.Velocity.Length,2.2f,5):direction*-.6f;
        if(slide){offender.SlideDirection=direction;offender.LastSlideAt=Seconds-.12f;}
        else offender.StumbleUntil=Seconds+.48f;
    }
    void FallDown(Footballer p,Point direction,float severity)
    {
        var facing=new Point(MathF.Cos(p.Facing),MathF.Sin(p.Facing));
        float impact=Point.Dot(direction.Unit,facing);
        p.FallSpeed=p.Velocity.Length;p.FallSeverity=Math.Clamp(severity,0,1);
        p.FallVariant=p.FallSpeed>4.8f && severity>.65f?4:impact<-.45f?1:impact>.45f?0:direction.Y*facing.X-direction.X*facing.Y>0?2:3;
        p.FallAt=Seconds+.055f;p.FallUntil=Seconds+2+p.FallSeverity*.65f;
        p.FallDirection=direction.Length>.01f?direction.Unit:new Point(MathF.Cos(p.Facing),MathF.Sin(p.Facing));
        p.FallVelocity=p.FallDirection*(2.8f+p.FallSeverity*2.8f)+p.Velocity*.45f;
        p.Velocity=new();p.VisualSpeed=0;p.BurstRemaining=0;p.RunUntil=0;p.Action="Падает";
        p.Recovery=Math.Max(p.Recovery,p.FallUntil-Seconds);
        AssessFallInjury(p,severity);
    }
    void AdvanceFalls(float dt)
    {
        foreach(var p in Players)
        {
            if(p.SentOff && Seconds>=p.ImpactUntil)continue;
            if(Seconds<p.ImpactUntil && Seconds>=p.FallUntil)
            {
                p.Position=Clamp(p.Position+p.ImpactVelocity*dt);
                p.ImpactVelocity*=MathF.Exp(-dt*(p.ImpactSlide?3:7));
                p.Velocity=new();p.Action=p.ImpactSlide?"Завершает подкат":"Теряет равновесие после контакта";
            }
            float age=InjuryAnimationSeconds(p)-p.FallAt;
            if(age<0 || age>.62f || p.FallVelocity.Length<.02f)continue;
            p.VisualBefore=p.Position;
            p.Position=Clamp(p.Position+p.FallVelocity*dt);
            p.VisualVelocity=(p.Position-p.VisualBefore)*(1/Math.Max(dt,.001f));
            p.FallVelocity*=MathF.Exp(-dt*4.2f);
            p.Action="Падает от столкновения";
        }
    }
}
public static partial class HumanFigure
{
    public static float FallBlend(Footballer p,MatchSimulation m)
    {
        float animationSeconds=m.InjuryAnimationSeconds(p);
        float age=animationSeconds-p.FallAt,remaining=p.FallUntil-animationSeconds;
        return Smooth(age/(p.FallVariant==4?.58f:.44f))*Smooth(remaining/.75f);
    }
    static List<Part> FallenPose(Footballer p,MatchSimulation m,List<Part> buffer=null)
    {
        var parts=buffer??new List<Part>(16);float fall=FallBlend(p,m),angle=fall*1.5f;
        var axis=p.FallDirection;var side=new Point(-axis.Y,axis.X);
        Point Joint(float lateral,float ahead,float z)
        {
            var ground=side*lateral+axis*(ahead*MathF.Cos(angle)+(z-.5f)*MathF.Sin(angle));
            float height=.04f+z*MathF.Cos(angle)-ahead*MathF.Sin(angle);
            return new(ground.X,ground.Y*GroundScale-height*.77f);
        }
        string shirt=p.Keeper?"#f5dc68":p.Team==0?"#46c7ed":"#fc8b61";
        string shorts=p.Team==0?"#193d60":"#f3e4cb";
        string skin=PlayerHeadProfiles.Skin(p.Profile.CatalogId,p.Profile.SkinTone,p.Id);
        void Bone(Point a,Point b,float w,string color)=>parts.Add(new(a,b,w,color));
        foreach(int s in new[]{-1,1})
        {
            var hip=Joint(s*.14f,0,.85f);var knee=Joint(s*.18f,-fall*.22f,.46f);var foot=Joint(s*.2f,-fall*.13f,.07f);
            Bone(hip,knee,.21f,shorts);Bone(knee,foot,.14f,shirt);Bone(foot,foot+axis*.15f,.16f,"#17282b");
        }
        Bone(Joint(0,0,.85f),Joint(0,0,1.38f),.48f,shirt);
        foreach(int s in new[]{-1,1})
        {
            var shoulder=Joint(s*.26f,0,1.33f);var elbow=Joint(s*.4f,-fall*.12f,1.05f);var hand=Joint(s*.34f,-fall*.08f,.8f);
            Bone(shoulder,elbow,.17f,shirt);Bone(elbow,hand,.12f,skin);
        }
        Bone(Joint(0,0,1.47f),Joint(0,0,1.7f),.31f,skin);Bone(Joint(0,0,1.7f),Joint(0,0,1.77f),.29f,PlayerHeadProfiles.Hair(p.Profile.CatalogId,p.Profile.HairTone));return parts;
    }
}