#pragma once

#include <J3ML/Geometry/Common.h>
#include <J3ML/Geometry/Shape.h>
#include <vector>
#include <J3ML/LinearAlgebra/Vector3.h>


namespace J3ML::Geometry
{
    using namespace J3ML::LinearAlgebra;

    // Represents a three-dimensional closed geometric solid defined by flat polygonal faces.
    class Polyhedron : public Shape
    {
    public:
        // Stores a list of indices of a single face of a Polygon
        struct Face
        {
            // Specifies the indices of the corner vertices of the polyhedron.
            // Indices point to the polyhedron vertex array.
            // The face vertices should all lie on the same plane.
            // The positive direction of the plane (the direction the face outwards normal points)
            // is the one where the vertices are wound in counter-clockwise order.
            std::vector<int> v;

            // Reverses the winding order of this face. This has the effect of reversing the direction
            // the normal of this face points to.
            void FlipWindingOrder();

        };

        // Specifies the vertices of this polyhedron.
        std::vector<Vector3> v;
        std::vector<Face> f;

        int NumVertices() const {return (int)v.size();}
        int NumFaces() const { return (int)f.size();}
        AABB MinimalEnclosingAABB() const;

        Vector3 Vertex(int vertexIndex) const;



        bool Contains(const Vector3&) const;
        bool Contains(const LineSegment&) const;
        bool Contains(const Triangle&) const;
        bool Contains(const Polygon&) const;
        bool Contains(const AABB&) const;
        bool Contains(const OBB&) const;
        bool Contains(const Frustum&) const;
        bool Contains(const Polyhedron&) const;

        bool ContainsConvex(const Vector3&, float epsilon = 1e-4f) const;
        bool ContainsConvex(const LineSegment&) const;
        bool ContainsConvex(const Triangle&) const;

        bool Intersects(const Line&) const;
        bool Intersects(const LineSegment&) const;
        bool Intersects(const Ray&) const;
        bool Intersects(const Plane&) const;
        bool Intersects(const Polyhedron&) const;
        bool Intersects(const AABB&) const;
        bool Intersects(const OBB&) const;
        bool Intersects(const Triangle&) const;
        bool Intersects(const Polygon&) const;
        bool Intersects(const Frustum&) const;
        bool Intersects(const Sphere&) const;
        bool Intersects(const Capsule&) const;

        float FaceContainmentDistance2D(int i, Vector3 vector3) const;

        bool IsClosed() const;

        Plane FacePlane(int faceIndex) const;

        std::vector<Polygon> Faces() const;

        int NumEdges() const;

        LineSegment Edge(int edgeIndex) const;

        std::vector<std::pair<int, int>> EdgeIndices() const;

        std::vector<LineSegment> Edges() const;

        Polygon FacePolygon(int faceIndex) const;

        Vector3 FaceNormal(int faceIndex) const;

        bool IsConvex() const;

        Vector3 ApproximateConvexCentroid() const;

        int ExtremeVertex(const Vector3 &direction) const;

        Vector3 ExtremePoint(const Vector3 &direction) const;

        /// Tests if the given face of this Polyhedron contains the given point.
        bool FaceContains(int faceIndex, const Vector3 &worldSpacePoint, float polygonThickness = 1e-3f) const;

        /// A helper for Contains() and FaceContains() tests: Returns a positive value if the given point is contained in the given face,
        /// and a negative value if the given point is outside the face. The magnitude of the return value reports a pseudo-distance
        /// from the point to the nearest edge of the face polygon. This is used as a robustness/stability criterion to estimate how
        /// numerically believable the result is.
        float FaceContainmentDistance2D(int faceIndex, const Vector3 &worldSpacePoint, float polygonThickness) const;
        void ProjectToAxis(const Vector3 &direction, float &outMin, float &outMax) const;
    protected:
    private:


    };
}