/// Copyright (c) 2021 Iiro Iivanainen, Harri Linna, Jere Pakkanen, Riikka Vilavaara
/// 
/// Permission is hereby granted, free of charge, to any person obtaining
/// a copy of this software and associated documentation files (the
/// "Software"), to deal in the Software without restriction, including
/// without limitation the rights to use, copy, modify, merge, publish,
/// distribute, sublicense, and/or sell copies of the Software, and to
/// permit persons to whom the Software is furnished to do so, subject to
/// the following conditions:
/// 
/// The above copyright notice and this permission notice shall be included
/// in all copies or substantial portions of the Software.
/// 
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
/// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
/// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
/// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
/// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
/// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
/// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

using System;
using System.Numerics;

using SharpGL;
using SharpGL.WPF;
using SharpGL.SceneGraph;
using SharpGL.SceneGraph.Assets;

namespace WPFOpenGL
{
    public class UserShape : Shape
    {
        public MainWindow.Planes plane;
        private Vector2 bottomleft = new Vector2();
        private Vector2 topright = new Vector2();
        private float depth;
        private Vector3 v0;
        private Vector3 v1;
        private Vector3 v2;
        private Vector3 v3;
        private Vector4 color = new Vector4(1f, 1f, 0f, 1f);

        /// v2        v3
        ///  +--------+
        ///  |        |
        ///  |        |
        ///  |        |
        ///  +--------+
        /// v0        v1
        public UserShape(Vector2 start, Vector2 end, float depth, MainWindow.Planes plane)
        {
            this.plane = plane;
            this.depth = depth;

            bottomleft.X = MathF.Min(start.X, end.X);
            bottomleft.Y = MathF.Min(start.Y, end.Y);

            topright.X = MathF.Max(start.X, end.X);
            topright.Y = MathF.Max(start.Y, end.Y);

            calculateVertices();
        }
        public UserShape(Vector3 start, Vector3 end, MainWindow.Planes plane)
        {
            this.plane = plane;

            if (plane == MainWindow.Planes.XY)
            {
                SetStartEnd(new Vector2(start.X, start.Y), new Vector2(end.X, end.Y), start.Z);
            }
            if (plane == MainWindow.Planes.XZ)
            {
                SetStartEnd(new Vector2(start.X, start.Z), new Vector2(end.X, end.Z), start.Y);
            }
            if (plane == MainWindow.Planes.YZ)
            {
                SetStartEnd(new Vector2(start.Y, start.Z), new Vector2(end.Y, end.Z), start.X);
            }
        }
        public void SetColor(Vector4 color)
        {
            this.color = color;
        }
        public void SetStartEnd(Vector2 start, Vector2 end, float depth)
        {
            this.depth = depth;

            bottomleft.X = MathF.Min(start.X, end.X);
            bottomleft.Y = MathF.Min(start.Y, end.Y);

            topright.X = MathF.Max(start.X, end.X);
            topright.Y = MathF.Max(start.Y, end.Y);

            calculateVertices();
        }
        public void SetStartEnd(Vector3 start, Vector3 end)
        {
            if (plane == MainWindow.Planes.XY)
            {
                SetStartEnd(new Vector2(start.X, start.Y), new Vector2(end.X, end.Y), start.Z);
            }
            
            if (plane == MainWindow.Planes.XZ)
            {
                SetStartEnd(new Vector2(start.X, start.Z), new Vector2(end.X, end.Z), start.Y);
            }

            if (plane == MainWindow.Planes.YZ)
            {
                SetStartEnd(new Vector2(start.Y, start.Z), new Vector2(end.Y, end.Z), start.X);
            }

            calculateVertices();
        }
        private void calculateVertices()
        {
            if (plane == MainWindow.Planes.XY)
            {
                v0 = new Vector3(bottomleft.X, bottomleft.Y, depth);
                v1 = new Vector3(topright.X, bottomleft.Y, depth);
                v2 = new Vector3(bottomleft.X, topright.Y, depth);
                v3 = new Vector3(topright.X, topright.Y, depth);
            }

            if (plane == MainWindow.Planes.XZ)
            {
                v0 = new Vector3(bottomleft.X, depth, bottomleft.Y);
                v1 = new Vector3(topright.X, depth, bottomleft.Y);
                v2 = new Vector3(bottomleft.X, depth, topright.Y);
                v3 = new Vector3(topright.X, depth, topright.Y);
            }

            if (plane == MainWindow.Planes.YZ)
            {
                v0 = new Vector3(depth, bottomleft.X, bottomleft.Y);
                v1 = new Vector3(depth, topright.X, bottomleft.Y);
                v2 = new Vector3(depth, bottomleft.X, topright.Y);
                v3 = new Vector3(depth, topright.X, topright.Y);
            }
        }

        public override bool IntersectRay(Vector3 rayOrigin, Vector3 rayDirection, out Vector3 hit, out float distance)
        {
            hit = new Vector3(0f, 0f, 0f);
            distance = -1f;

            if (!isVisible || !isRaycastable) return false;

            return RayCast.IntersectQuad(rayOrigin, rayDirection, v0, v1, v2, v3, out hit, out distance);
        }

        public override void Render(OpenGL openGL)
        {
            openGL.Begin(OpenGL.GL_LINE_LOOP);

                openGL.Color(color.X, color.Y, color.Z, color.W);

                openGL.Vertex(v0.X, v0.Y, v0.Z);
                openGL.Vertex(v1.X, v1.Y, v1.Z);
                openGL.Vertex(v3.X, v3.Y, v3.Z);
                openGL.Vertex(v2.X, v2.Y, v2.Z);
                openGL.Vertex(v0.X, v0.Y, v0.Z);

            openGL.End();
        }
    }
}