using Sandbox;
using Sandbox.UI;
using Socer;
using System;

public sealed class SetPieceAimInput : Panel
{
    public MatchController Game {get;set;}
    public FootballWorldPanel World {get;set;}
    public Action<float,float> Pick {get;set;}
    bool panning;
    Vector2 panLast;
    Vector2 lastClick;
    float lastClickAt=-10;
    int lastPlayer=-1;
    Vector2 Fraction(Vector2 pixel)=>new(pixel.x/Math.Max(1,Box.Rect.Width),pixel.y/Math.Max(1,Box.Rect.Height));
    int FindPlayer(Vector2 pixel)
    {
        if(Game==null || World==null)return -1;
        var candidates=new System.Collections.Generic.List<(int Id,float Distance)>();
        foreach(var player in Game.Match.ActivePlayers)
        {
            var foot=World.Project(player.Position,.15f);var head=World.Project(player.Position,1.7f);
            var a=new Vector2(foot.x*Box.Rect.Width,foot.y*Box.Rect.Height);
            var b=new Vector2(head.x*Box.Rect.Width,head.y*Box.Rect.Height);
            var segment=b-a;float length2=segment.x*segment.x+segment.y*segment.y;
            var offset=pixel-a;float t=length2<1?0:(offset.x*segment.x+offset.y*segment.y)/length2;
            if(t>1.12f || (t<-.2f && offset.Length>25))continue;
            float d=(pixel-a-segment*Math.Clamp(t,0,1)).Length;
            if(d<24)candidates.Add((player.Id,d));
        }
        if(candidates.Count==0)return -1;
        candidates.Sort((a,b)=>a.Distance.CompareTo(b.Distance));
        int index=0;
        if(Time.Now-lastClickAt<1.1f && (pixel-lastClick).Length<20)
        {
            int previous=candidates.FindIndex(p=>p.Id==lastPlayer);
            if(previous>=0)index=(previous+1)%candidates.Count;
        }
        lastClickAt=Time.Now;lastClick=pixel;lastPlayer=candidates[index].Id;
        return lastPlayer;
    }
    public bool TrySelectPlayer(Vector2 pixel)
    {
        int player=FindPlayer(pixel);
        if(player<0)return false;
        Game.SelectPlayer(player);return true;
    }
    public bool InsideGoalMouth(Vector2 pixel)
    {
        if(Game==null || World==null)return false;
        float x=Game.Match.HomeAttackGoal.X;
        var a=World.Project(new Point(x,30.34f),0);
        var b=World.Project(new Point(x,37.66f),0);
        var c=World.Project(new Point(x,37.66f),2.44f);
        var d=World.Project(new Point(x,30.34f),2.44f);
        var p=Fraction(pixel);
        return InTriangle(p,a,b,c) || InTriangle(p,a,c,d);
    }
    static float Cross(Vector2 a,Vector2 b)=>a.x*b.y-a.y*b.x;
    static bool InTriangle(Vector2 point,Vector2 a,Vector2 b,Vector2 c)
    {
        float area=Cross(b-a,c-a);
        if(!float.IsFinite(area) || Math.Abs(area)<.00000001f)return false;
        float u=Cross(b-a,point-a)/area,v=Cross(point-a,c-a)/area;
        return u>=-.0001f && v>=-.0001f && u+v<=1.0001f;
    }
    void MovePan(Vector2 pixel)
    {
        if(!panning || World==null || Game==null)return;
        if((pixel-panLast).Length<.001f)return;
        Game.PanBroadcastCamera(World.CameraPanDelta(Fraction(panLast),Fraction(pixel)));
        panLast=pixel;
    }
    // The native pointer handler and editor interaction checks share exactly
    // the same player hit-test, pixel mapping and aim callback.
    public bool AimAt(Vector2 pixel)
    {
        if(Game==null || World==null || Pick==null)return false;
        // A keeper or wall can cover the chosen point on screen. Inside the
        // projected goal opening this click means aim; elsewhere players still
        // receive the normal inspection/selection hit test.
        if(!InsideGoalMouth(pixel) && TrySelectPlayer(pixel))return false;
        Pick.Invoke(Math.Clamp(pixel.x/Math.Max(1,Box.Rect.Width),0,1),
            Math.Clamp(pixel.y/Math.Max(1,Box.Rect.Height),0,1));
        return true;
    }
    protected override void OnMouseDown(MousePanelEvent e)
    {
        base.OnMouseDown(e);
        if(HasMouseCapture)SetMouseCapture(false);
        if(e.MouseButton==MouseButtons.Right){panning=true;panLast=MousePosition;return;}
        if(e.MouseButton!=MouseButtons.Left)return;
        AimAt(MousePosition);
    }
    protected override void OnMouseUp(MousePanelEvent e)
    {
        base.OnMouseUp(e);
        if(e.MouseButton!=MouseButtons.Right)return;
        MovePan(MousePosition);panning=false;if(HasMouseCapture)SetMouseCapture(false);
    }
    public override void OnMouseWheel(Vector2 value)
    {
        base.OnMouseWheel(value);
        Game?.ZoomBroadcastCamera(value.y);
    }
    public override void Tick(){base.Tick();if(panning)MovePan(MousePosition);}
}