#include <GLUT/glut.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>

#define SIZE 200
#define CLNUM 3

typedef struct point{
	double x;
	double y;
	int cls;
}Point;
typedef enum state{
	Init,
	KS,
	MS,
}STATE;

Point data[SIZE];
Point center[CLNUM];
STATE state = Init;

void make_data(void)
{
 int i;
 for(i = 0; i < SIZE; i++){
	 data[i].x = rand()%200;
	 data[i].y = rand()%200;
	 data[i].cls = -1;
 }

 for(i = 0; i < CLNUM; i++){
	 center[i].x = rand()%200;
	 center[i].y = rand()%200;
	 center[i].cls=i;
 }

}

void Kstep(void)
{
	int i,j;
	double min_range;
	for(i = 0; i < SIZE; i ++){
		min_range=4000.0; // > sqrt(x**2+y**2)
		for(j = 0; j < CLNUM; j++){
			if(min_range > sqrt(pow(data[i].x-center[j].x,2)+pow(data[i].y-center[j].y,2))){
				min_range = sqrt(pow(data[i].x-center[j].x,2)+pow(data[i].y-center[j].y,2));
				data[i].cls=j;
			}
		}
	}
}
void Mstep(void)
{
	int i;
	double sum_x[CLNUM],sum_y[CLNUM];
	int count_cls[CLNUM];
	for(i = 0; i < CLNUM; i++) {
		sum_x[i] = sum_y[i] = count_cls[i] = 0;
	}

	for(i = 0; i < SIZE; i++) {
		sum_x[data[i].cls] += data[i].x;
		sum_y[data[i].cls] += data[i].y;
		count_cls[data[i].cls]++;
	}

	for(i = 0; i < CLNUM; i++) {
		center[i].x = sum_x[i] / count_cls[i];
		center[i].y = sum_y[i] / count_cls[i];
	}
}

void display(void)
{
	printf("%d\n",state);
	int i;
	glClearColor(0.0, 0.0, 0.0, 0.0);	// 画面のクリア色(背景色)
	glClear(GL_COLOR_BUFFER_BIT);		// バッファのクリア
	switch (state) {
		case Init:
			glPointSize(5.0);					// 点の太さ
			glBegin(GL_POINTS);					// 点の座標を記述開始
			//glColor4f(0.7, 0.2, 0.2, 0.0);	// 点の色(RGBA)
			for(i = 0; i < SIZE; i++){
				switch (data[i].cls) {
					case -1:
						glColor4f(1, 1, 1, 1);
						break;
					case 0:
						glColor4f(1, 0, 0, 1);
						break;
					case 1:
						glColor4f(0, 1, 0, 1);
						break;
					case 2:
						glColor4f(0, 0, 1, 1);
						break;
					default:
						break;
				}
				glVertex2f((data[i].x-100)/100, (data[i].y-100)/100);			// 点の座標
			}
			state=KS;
			break;
		case KS:
		puts("KS");
			Kstep();
			glPointSize(5.0);					// 点の太さ
			glBegin(GL_POINTS);					// 点の座標を記述開始
			for(i = 0; i < SIZE; i++){
				switch (data[i].cls) {
					case -1:
						glColor4f(1, 1, 1, 1);
						break;
					case 0:
						glColor4f(1, 0, 0, 1);
						break;
					case 1:
						glColor4f(0, 1, 0, 1);
						break;
					case 2:
						glColor4f(0, 0, 1, 1);
						break;
					default:
						break;
				}
				glVertex2f((data[i].x-100)/100, (data[i].y-100)/100);			// 点の座標
			}
			for(i = 0; i<CLNUM;i++){
				switch (center[i].cls) {
					case 0:
					glColor4f(1,0.5,0.5,1);
					break;
					case 1:
					glColor4f(0.5, 1, 0.5, 1);
					break;
					case 2:
					glColor4f(0.5, 0.5, 1, 1);
					break;
					default:
					break;
				}
				glVertex2f((center[i].x-100)/100, (center[i].y-100)/100);
			}
			state=MS;
			break;
		case MS:
			Mstep();
			glPointSize(5.0);					// 点の太さ
			glBegin(GL_POINTS);					// 点の座標を記述開始
			for(i = 0; i < SIZE; i++){
				switch (data[i].cls) {
					case -1:
						glColor4f(1, 1, 1, 1);
						break;
					case 0:
						glColor4f(1, 0, 0, 1);
						break;
					case 1:
						glColor4f(0, 1, 0, 1);
						break;
					case 2:
						glColor4f(0, 0, 1, 1);
						break;
					default:
						break;
				}
				glVertex2f((data[i].x-100)/100, (data[i].y-100)/100);			// 点の座標
			}
			for(i = 0; i<CLNUM;i++){
				switch (center[i].cls) {
					case 0:
					glColor4f(1,0.5,0.5,1);
					break;
					case 1:
					glColor4f(0.5, 1, 0.5, 1);
					break;
					case 2:
					glColor4f(0.5, 0.5, 1, 1);
					break;
					default:
					break;
				}
				glVertex2f((center[i].x-100)/100, (center[i].y-100)/100);
			}
			state=KS;
			break;
		default:
			break;
	}


	glEnd();							// 座標の記述終了
	glFlush();							// コマンドの実行
}

void mouse(int button, int state, int x, int y)
{
  switch (button) {
  case GLUT_LEFT_BUTTON:
	if(state==GLUT_DOWN){
		glutPostRedisplay();
	}
    break;
  case GLUT_RIGHT_BUTTON:
    break;
  default:
    break;
  }
}

int main(int argc, char *argv[])
{
	srand((unsigned)time(NULL));
	make_data();
	glutInitWindowPosition(100, 100);	// 画面の出現位置
	glutInitWindowSize(400, 300);		// 画面サイズ(400*300px)
	glutInit(&argc, argv);				// GLUTの初期化
	glutInitDisplayMode(GLUT_RGBA);		// 画面のモード(RGBA色空間を使う)
	glutCreateWindow("kmeans");			// 画面の名前
	glutDisplayFunc(display);			// GLUTの再描画関数を登録
	glutMouseFunc(mouse);
	glutMainLoop();						// イベントループを繰り返し実行
	return 0;
}