using System.Collections.Generic;
using System.Numerics;
using ACE.Server.Physics.Common;

namespace ACE.Server.Physics.Collision
{
    public class BBox
    {
        public Vector3 Min;
        public Vector3 Max;

        public BBox() { }

        public BBox(List<DatLoader.Entity.Polygon> polys, Matrix4x4 transform)
        {
            Min = new Vector3(float.MaxValue, float.MaxValue, float.MaxValue);
            Max = new Vector3(float.MinValue, float.MinValue, float.MinValue);

            foreach (var poly in polys)
            {
                foreach (var vertex in poly.Vertices)
                {
                    var v = Vector3.Transform(vertex.Origin, transform);

                    if (v.X < Min.X) Min.X = v.X;
                    if (v.Y < Min.Y) Min.Y = v.Y;
                    if (v.Z < Min.Z) Min.Z = v.Z;

                    if (v.X > Max.X) Max.X = v.X;
                    if (v.Y > Max.Y) Max.Y = v.Y;
                    if (v.Z > Max.Z) Max.Z = v.Z;
                }
            }
        }

        public void AdjustBBox(Vector3 v)
        {
            if (v.X < Min.X) Min.X = v.X;
            if (v.Y < Min.Y) Min.Y = v.Y;
            if (v.Z < Min.Z) Min.Z = v.Z;

            if (v.X > Max.X) Max.X = v.X;
            if (v.Y > Max.Y) Max.Y = v.Y;
            if (v.Z > Max.Z) Max.Z = v.Z;
        }

        public void BuildBoundingBox(BBox bbox)
        {
            if (Min.X < bbox.Min.X) bbox.Min.X = Min.X;
            if (Min.Y < bbox.Min.Y) bbox.Min.Y = Min.Y;
            if (Min.Z < bbox.Min.Z) bbox.Min.Z = Min.Z;

            if (Max.X > bbox.Max.X) bbox.Max.X = Max.X;
            if (Max.Y > bbox.Max.Y) bbox.Max.Y = Max.Y;
            if (Max.Z > bbox.Max.Z) bbox.Max.Z = Max.Z;
        }

        /// <summary>
        /// Returns TRUE if point is inside box
        /// </summary>
        public bool Contains(Vector3 point)
        {
            return (point.X >= Min.X && point.X <= Max.X) &&
                   (point.Y >= Min.Y && point.Y <= Max.Y) &&
                   (point.Z >= Min.Z && point.Z <= Max.Z);
        }

        public void ConvertToGlobal(Position pos)
        {
            var transform = Matrix4x4.CreateFromQuaternion(pos.Frame.Orientation) * Matrix4x4.CreateTranslation(pos.Frame.Origin);
            Min = Vector3.Transform(Min, transform);
            Max = Vector3.Transform(Max, transform);
            // adjust?
        }

        public Vector3 GetCenter()
        {
            return new Vector3((Max.X - Min.X) * 0.5f, (Max.Y - Min.Y) * 0.5f, (Max.Z - Min.Z) * 0.5f);
        }

        public List<Vector3> GetCorners()
        {
            // cache?
            return new List<Vector3>()
            {
                new Vector3(Min.X, Min.Y, Min.Z),
                new Vector3(Min.X, Min.Y, Max.Z),
                new Vector3(Min.X, Max.Y, Min.Z),
                new Vector3(Min.X, Max.Y, Max.Z),
                new Vector3(Max.X, Min.Y, Min.Z),
                new Vector3(Max.X, Min.Y, Max.Z),
                new Vector3(Max.X, Max.Y, Min.Z),
                new Vector3(Max.X, Max.Y, Max.Z),
            };
        }

        public void InitForAdjustment()
        {
            Min = new Vector3(float.MaxValue, float.MaxValue, float.MaxValue);
            Max = new Vector3(float.MinValue, float.MinValue, float.MinValue);
        }

        public void LocalToGlobal(BBox fromBox, Position fromPos, Position toPos)
        {
            Min = toPos.LocalToGlobal(fromPos, fromBox.Min);
            Max = toPos.LocalToGlobal(fromPos, fromBox.Max);

            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Max.X, fromBox.Max.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Max.X, fromBox.Min.Y, fromBox.Max.Z)));
            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Min.X, fromBox.Max.Y, fromBox.Max.Z)));
            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Min.X, fromBox.Max.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Max.X, fromBox.Min.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToGlobal(fromPos, new Vector3(fromBox.Min.X, fromBox.Min.Y, fromBox.Max.Z)));
        }

        public void LocalToLocal(BBox fromBox, Position fromPos, Position toPos)
        {
            Min = toPos.LocalToLocal(fromPos, fromBox.Min);
            Max = toPos.LocalToLocal(fromPos, fromBox.Max);

            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Max.X, fromBox.Max.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Max.X, fromBox.Min.Y, fromBox.Max.Z)));
            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Min.X, fromBox.Max.Y, fromBox.Max.Z)));
            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Min.X, fromBox.Max.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Max.X, fromBox.Min.Y, fromBox.Min.Z)));
            AdjustBBox(toPos.LocalToLocal(fromPos, new Vector3(fromBox.Min.X, fromBox.Min.Y, fromBox.Max.Z)));
        }
    }
}