// Peter Bui
// CSE 40166 Computer Graphics (Fall 2010)
// Example 19: drawables

#include "drawable.h"
#include "drawable_circle.h"
#include "drawable_star.h"
#include "drawable_initials.h"
 
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <list>

#ifdef __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif

using namespace std;

// Constants -------------------------------------------------------------------

#define WHEEL_UP    3
#define WHEEL_DOWN  4

// Global variables ------------------------------------------------------------

static GLint WindowWidth  = 640;
static GLint WindowHeight = 480;

static Drawable *CurrentDrawable = NULL;
static Drawable *StaticCircle    = NULL;
static Drawable *StaticStar      = NULL;
static Drawable *StaticInitials  = NULL;

static list<Drawable*> Drawables;

// Initialize scene ------------------------------------------------------------

void
init_scene()
{
    glViewport(0, 0, WindowWidth, WindowHeight);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluOrtho2D(0, WindowWidth, 0, WindowHeight);

    glMatrixMode(GL_MODELVIEW);

    glutSetCursor(GLUT_CURSOR_NONE);

    StaticCircle    = new Circle();
    StaticStar      = new Star();
    StaticInitials  = new Initials();
    CurrentDrawable = StaticCircle;
}

// Display callback ------------------------------------------------------------

void
display()
{
    glClear(GL_COLOR_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    
    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
    for (list<Drawable*>::iterator it = Drawables.begin(); it != Drawables.end(); it++)
	(*it)->draw();

    glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
    CurrentDrawable->draw();

    glutSwapBuffers();
}

// Reshape callback ------------------------------------------------------------

void
reshape(GLsizei nw, GLsizei nh)
{
    WindowWidth  = nw;
    WindowHeight = nh;
    
    init_scene();
}

// Keyboard callback -----------------------------------------------------------

void
keyboard(unsigned char key, int x, int y)
{
    switch (key) {
	case 'q':
	case 'Q':
	    exit(EXIT_SUCCESS);
	    break;
	case '1':
	    CurrentDrawable = StaticCircle;
	    break;
	case '2':
	    CurrentDrawable = StaticStar;
	    break;
	case '3':
	    CurrentDrawable = StaticInitials;
	    break;
	case 'w':
	    break;
    }
    
    glutPostRedisplay();
}

// Mouse callback --------------------------------------------------------------

void
mouse(int button, int state, int x, int y)
{
    CurrentDrawable->x = x;
    CurrentDrawable->y = WindowHeight - y;

    if (button == GLUT_LEFT_BUTTON && state == GLUT_DOWN) {
    	Drawable *d = NULL;

	if (CurrentDrawable == StaticCircle)
	    d = new Circle(x, WindowHeight - y);
	else if (CurrentDrawable == StaticStar)
	    d = new Star(x, WindowHeight - y);
	else if (CurrentDrawable == StaticInitials)
	    d = new Initials(x, WindowHeight - y);
	else
	    d = NULL;

	if (d) 
	    Drawables.push_back(d);
    }
    
    if (button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN) {
	for (list<Drawable*>::iterator it = Drawables.begin(); it != Drawables.end(); it++) 
	    delete *it;
	Drawables.clear();
    }

    if (button == WHEEL_UP && state == GLUT_DOWN) {
	if (CurrentDrawable == StaticCircle)
	    CurrentDrawable = StaticStar;
	else if (CurrentDrawable == StaticStar)
	    CurrentDrawable = StaticInitials;
	else
	    CurrentDrawable = StaticCircle;
    }
    
    if (button == WHEEL_DOWN && state == GLUT_DOWN) {
	if (CurrentDrawable == StaticCircle)
	    CurrentDrawable = StaticInitials;
	else if (CurrentDrawable == StaticStar)
	    CurrentDrawable = StaticCircle;
	else
	    CurrentDrawable = StaticStar;
    }
    
    glutPostRedisplay();
}

// Passive motion callback -----------------------------------------------------

void
passive_motion(int x, int y)
{
    CurrentDrawable->x = x;
    CurrentDrawable->y = WindowHeight - y;
    
    glutPostRedisplay();
}

// Main execution --------------------------------------------------------------

int
main(int argc, char *argv[])
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
    glutInitWindowSize(WindowWidth, WindowHeight);
    glutCreateWindow("drawables");
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutKeyboardFunc(keyboard);
    glutMouseFunc(mouse);
    glutPassiveMotionFunc(passive_motion);

    init_scene();

    glutMainLoop();

    return (EXIT_SUCCESS);
}

// vim: set sts=4 sw=4 ts=8 ft=cpp: --------------------------------------------