// Librairies
#include "Scene.h"
#include "Objects.h"

// Constructor of the class Scene
Scene::Scene() {
    // Initialise the material specular color
    mat_specular[0] = 1.0;
    mat_specular[1] = 1.0;
    mat_specular[2] = 1.0;
    mat_specular[3] = 1.0;
    
    // Initialize the material shininess
    mat_shininess[0] = 50.0;
    
    // Initialise the light source position
    light_position[0] = 20.0;
    light_position[1] = 9.0;
    light_position[2] = 15.0;
    light_position[3] = 0.0;
    
    // Initialise the ambient color of the light
    ambient_color[0] = 1.0;
    ambient_color[1] = 1.0;
    ambient_color[2] = 1.0;
    ambient_color[3] = 0.7;
    
    // Initialise the diffuse light color
    white_light[0] = 1.0;
    white_light[1] = 1.0;
    white_light[2] = 1.0;
    white_light[3] = 1.0;
    
    // Initialise the camera angles
    camera_angle1 = 0.0;
    camera_angle2 = 0.0;
}

// Destructor of the class Scene
Scene::~Scene() {
    
}

// Init method
void Scene::init() {
    glClearColor(0.0, 0.0, 0.0, 0.0);           // Select the color for the background
    glShadeModel(GL_SMOOTH);
    glClearDepth(1.0);
    
    // Lighting settings
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);        // Specular color of the material
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);      // Shininess of the material
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);        // Position of the light source
    glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_color);          // Ambient color of the light
    glLightfv(GL_LIGHT0, GL_DIFFUSE, white_light);            // Diffuse color of the light
    glLightfv(GL_LIGHT0, GL_SPECULAR, white_light);           // Specular color of the light
    
    glEnable(GL_LIGHTING);                                          // Activate the lighting
    glEnable(GL_LIGHT0);                                            // Activate a light source
    glEnable(GL_DEPTH_TEST);                                        // Activate the Depth buffer
}

// Display method
void Scene::display(const Context& context) const {
    glClearColor(0,0,0,0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

    // Define the position and the direction of the camera
	gluLookAt(30,10,0,0,0,0,0,1,0);
	
    // Rotation of the camera due to the mouse mouvement	
	glRotatef(camera_angle2, 0.0, 0.0, 1.0);
    glRotatef(camera_angle1, 0.0, 1.0, 0.0);
    
    // Draw all objects in the context
    for(int i=0; i<context.getNbObjects(); ++i)
    {
        // Copy the active matrix on the matrix stack
       glPushMatrix();
       
        // Draw the object
        context.getObject(i).draw();   
        
       // Remove the matrix on the top of the matrix stack
       glPopMatrix();
    }
   
	// Change the buffers
	SDL_GL_SwapBuffers();
}

// Reshape the window
void Scene::reshape(int width, int height) {
    glViewport(0,0,width,height);
	glMatrixMode(GL_PROJECTION);                           // Specify the matrix that will be modified
	glLoadIdentity();                                      // Load the identity matrix before the transformations
	gluPerspective(45.0, (float) width/height, 0.1f, 150.0f);
	glMatrixMode(GL_MODELVIEW);                            // Specify the matrix that will be modified
	glLoadIdentity();                                      // Load the identity matrix before the transformations
}