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

#include <stdio.h>
#include <stdlib.h>

#include <dff.h>

#define ESCAPE 27

DFF *dff;

float xpos = 0.0f, ypos = 0.0f, zpos = -6.8f;
float xrot = -66.0f, yrot = 0.0f, zrot = -120.0f;
int textured;

void exitprog(int signal)
{
	printf("Exiting...%d\n", signal);
	exit(signal);
}

void
keypress(unsigned char key, int x, int y)
{
	switch(key) {
	case 'q':
		yrot -= 0.7f;
		break;
	case 'Q':
		yrot -= 2.0f;
		break;
	case 'e':
		yrot += 0.7f;
		break;
	case 'E':
		yrot += 2.0f;
		break;
	case 'h':
		xpos += 0.1f;
		break;
	case 'H':
		xpos += 0.2f;
		break;
	case 'j':
		ypos += 0.1f;
		break;
	case 'J':
		ypos += 0.2f;
		break;
	case 'k':
		ypos -= 0.1f;
		break;
	case 'K':
		ypos -= 0.2f;
		break;
	case 'l':
		xpos -= 0.1f;
		break;
	case 'L':
		xpos -= 0.2f;
		break;
	case 't':
	case 'T':
		if (textured == 1)
			glDisable(GL_TEXTURE_2D);
		else
			glEnable(GL_TEXTURE_2D);
		textured = !textured;
		break;
/*
	case 'O':
		if (whichobj == 0)
			whichobj = objscount;
		whichobj--;
		whichframe = 0;
		isvisible();
		break;
	case 'o':
		whichobj++;
		if (whichobj == objscount)
			whichobj = 0;
		isvisible();
		break;
	case 'F':
		if (whichframe == 0)
			whichframe = objs[whichobj].mdl->clp->frmcount;
		whichframe--;
		isvisible();
		break;
	case 'f':
		whichframe++;
		if (whichframe == objs[whichobj].mdl->clp->frmcount)
			whichframe = 0;
		isvisible();
		break;
	case 'V':
	case 'v':
		objs[whichobj].mdl->clp->frm[whichframe].display =
			!objs[whichobj].mdl->clp->frm[whichframe].display;
		isvisible();
		break;
*/
	case 'c':
	case 'C':
		printf("\nCamera position: %f %f %f\n", xpos, ypos, zpos);
		printf("Camera roatation: %f %f %f\n\n", xrot, yrot, zrot);
		break;
/*
	case 'i':
	case 'I':
		objscount = 0;
		if (objs != NULL) {
			DestroyObjs(objs);
			free(objs);
		if ((objs = ReadIde(ide)) == NULL) {
			objscount = 0;
			exitprog(0);
		objs->mdl = LoadModel(objs->Model, objs->Texture, img, 0);
		objscount = 1;
		break;
*/
	case ESCAPE:
		exitprog(0);
	default:
		break;
	}
	glutPostRedisplay();
}

void
spkeypress(int key, int x, int y)
{
	switch (key) {
	case GLUT_KEY_UP:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			xrot -= 2.0f;
		else
			xrot -= 0.7f;
		break;
	case GLUT_KEY_DOWN:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			xrot += 2.0f;
		else
			xrot += 0.7f;
		break;
	case GLUT_KEY_LEFT:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			zrot -= 2.0f;
		else
			zrot -= 0.7f;
		break;
	case GLUT_KEY_RIGHT:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			zrot += 2.0f;
		else
			zrot += 0.7f;
		break;
	case GLUT_KEY_PAGE_UP:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			zpos += 0.7f;
		else
			zpos += 0.2f;
		break;
	case GLUT_KEY_PAGE_DOWN:
		if (glutGetModifiers() == GLUT_ACTIVE_SHIFT)
			zpos -= 0.7f;
		else
			zpos -= 0.2f;
		break;
	default:
		break;
	}
	glutPostRedisplay();
}

void
resize(int w, int h)
{
	if(h == 0)
		h = 1;

	glViewport(0, 0, w, h);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(45.0f, (GLfloat) w/(GLfloat)h, 0.1f, 2000.0f);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
/*	glLightfv(GL_LIGHT0, GL_POSITION, LightPosition);
	glTranslatef(0.0f, 0.0f, 0.0f); */
}

void
drawclump(_clump *clp)
{
	int i, j, k, g, f;
	_split *split;
	vector3f *vert;

	for (i = 0; i < clp->natomic; i++) {
		g = clp->atm[i].geoindex;
		f = clp->atm[i].frmindex;
/*		glPushMatrix(); */
		for (j = 0; j < clp->geo[g].nsplit; j++) {
			split = &clp->geo[g].split[j];
			vert = clp->geo[g].vertex;

			glBegin(GL_TRIANGLE_STRIP);
			for (k = 0; k < split->nindex; k++) {
				glVertex3fv(vert[split->indices[k]]);
			}
		}
		glEnd();
	}
}

void
renderscene()
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glLoadIdentity();

	glTranslatef(xpos, ypos, zpos);
	glRotatef(xrot, 1.0f, 0.0f, 0.0f);
	glRotatef(yrot, 0.0f, 1.0f, 0.0f);
	glRotatef(zrot, 0.0f, 0.0f, 1.0f);

	drawclump(dff[0].clp);

	glutSwapBuffers();
}

int
main(int argc, char *argv[])
{
	int w, h;
	FILE *fdff;

	w = 800;
	h = 600;

	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_ALPHA | GLUT_DEPTH);
	glutInitWindowSize(w, h);
	glutCreateWindow("DFF Viewer");
	glutReshapeFunc(resize);
	glutSpecialFunc(&spkeypress);
	glutKeyboardFunc(&keypress);
	glutDisplayFunc(renderscene);

	if ((fdff = fopen(argv[1], "rb")) == NULL) {
		fprintf(stderr, "Couldn't open file %s\n", argv[1]);
		exitprog(1);
	}
	fseek(fdff, 0, SEEK_END);
	dff = dffread(fdff, 0, ftell(fdff));

	glClearColor(0.6f, 0.6f, 0.6f, 1.0f);
	glClearDepth(1.0);
	glDepthFunc(GL_LESS);
	glEnable(GL_DEPTH_TEST);
	glEnable(GL_ALPHA_TEST);
	glEnable(GL_NORMALIZE);
	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
	glShadeModel(GL_SMOOTH);
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(45.0f, (GLfloat) w/(GLfloat)h, 0.1f, 100.0f);

	glMatrixMode(GL_MODELVIEW);
	glutMainLoop();
	return 0;
}