using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using OpenGL4NET;

namespace Semestralka
{
    class Object
    {
        string objectName;
        int countOfVertex;
        private int vert;
        int countOfFaces;
        private int fac;
        Vector3[] vertex;
        uint[] index;
        uint vertexVBO, indexVBO;

        public Object(string objectName)
        {
            this.objectName = objectName;
            countOfVertex = 0;
            vert = 0;
            countOfFaces = 0;
            fac = 0;
        }

        public void setCountOfVertex(int countOfVertex)
        {
            this.countOfVertex = countOfVertex;
        }

        public void addedVertex()
        {
            countOfVertex++;
        }

        public void setCountOfFaces(int countOfFaces)
        {
            this.countOfFaces = countOfFaces;
        }

        public void addedFace()
        {
            countOfFaces++;
        }

        public void createVertexField()
        {
            vertex = new Vector3[countOfVertex];
        }

        public void createIndexFiels()
        {
            index = new uint[3 * countOfFaces];
        }

        public void addVertex(float x, float y, float z)
        {
            vertex[vert++] = new Vector3(x,y,z);
        }

        public void addFace(uint p1, uint p2, uint p3)
        {
            index[fac++] = p1;
            index[fac++] = p2;
            index[fac++] = p3;
        }

        public void createBuffers()
        {
            vertexVBO = gl.GenBuffer();
            gl.BindBuffer(GL.ARRAY_BUFFER, vertexVBO);
            gl.BufferData(GL.ARRAY_BUFFER, vertex.Length * 3 * sizeof(float), vertex, GL.STATIC_DRAW);

            indexVBO = gl.GenBuffer();
            gl.BindBuffer(GL.ELEMENT_ARRAY_BUFFER, indexVBO);   
            gl.BufferData(GL.ELEMENT_ARRAY_BUFFER, index.Length * sizeof(uint), index, GL.STATIC_DRAW);

            gl.BindBuffer(GL.ELEMENT_ARRAY_BUFFER, 0);
            gl.BindBuffer(GL.ARRAY_BUFFER, 0);
        }

        public void render()
        {
            //gl.Color3f(1f, 0f, 0f);
            gl.BindBuffer(GL.ARRAY_BUFFER, vertexVBO);
            gl.EnableClientState(GL.VERTEX_ARRAY);
            gl.VertexPointer(3, GL.FLOAT, 3 * sizeof(float), (IntPtr)0);

            gl.BindBuffer(GL.ELEMENT_ARRAY_BUFFER, indexVBO);

            gl.DrawElements(GL.TRIANGLES, 24, GL.UNSIGNED_INT, (IntPtr)0);
            gl.DisableClientState(GL.VERTEX_ARRAY);

            gl.BindBuffer(GL.ARRAY_BUFFER, 0);
            gl.BindBuffer(GL.ELEMENT_ARRAY_BUFFER, 0);
        }

        public void destroy()
        {
            gl.DeleteBuffer(vertexVBO);
            gl.DeleteBuffer(indexVBO);
        }

        public void objectInfo()
        {
            Console.WriteLine("Object name: " + objectName + "\ncount of vertex = " + countOfVertex + "\ncount of faces = " + countOfFaces);

            if (vertex != null)
            {
                for (int i = 0; i < vertex.Length; i++)
                {
                    Console.WriteLine("v" + i + " = " + vertex[i].x + " " + vertex[i].y + " " + vertex[i].z);
                }
            }
            if (index != null)
            {
                for (int i = 0; i < index.Length; i++)
                {
                    Console.WriteLine("f" + (i/3) + " = " + index[i] + " " + index[++i] + " " + index[++i]);
                }
            }
        }
    }
}