#include "GlutRender.hpp"

#include <GL/gl.h>
#include <GL/glut.h>
#include <cstring>

GlutRender& GlutRender::get_instance() {
    static GlutRender instance;
    return instance;
}

GlutRender::GlutRender() { }

void GlutRender::init(int* argc, char** argv,
        int wid, int hei, const char* win_name)
{
   glutInit(argc, argv);
   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize(wid, hei);
   glutCreateWindow(win_name);

   glClearColor(0.0, 0.0, 0.0, 0.0);
   glShadeModel(GL_FLAT);

   glutDisplayFunc(display_handle);
   glutReshapeFunc(reshape_handle);
}

void GlutRender::cleanup() {
}

void GlutRender::add_mesh(const Mesh* mesh) {
    meshes.insert(mesh);
}

void GlutRender::remove_mesh(const Mesh* mesh) {
    meshes.erase(mesh);
}

void GlutRender::run() {
}

void GlutRender::reshape(int wid, int hei) {
   glViewport(0, 0, (GLsizei) wid, (GLsizei) hei);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluOrtho2D(0.0, (GLdouble) wid, 0.0, (GLdouble) hei);
}

void GlutRender::display() {
    for(const Mesh* mesh: meshes) {
        const std::vector<Point>& points = mesh->get_vertices();
        for(const Face& face: mesh->get_faces()) {
            const Point& p0 = face.pt(0, points),
                         p1 = face.pt(2, points),
                         p2 = face.pt(2, points);
            glBegin(GL_TRIANGLES);
                glVertex3d(p0[0], p0[1], p0[2]);
                glVertex3d(p1[0], p1[1], p1[2]);
                glVertex3d(p2[0], p2[1], p2[2]);
            glEnd();
        }
    }
}

void GlutRender::reshape_handle(int wid, int hei) {
    get_instance().reshape(wid, hei);
}
void GlutRender::display_handle() {
    get_instance().display();
}