#include "fracture.h"

double th_p(double x, double y, double th) {
	if (x >= 0 && y >= 0) return th;
	else if (x <  0 && y >= 0) return M_PI - th;
	else if (x <  0 && y <  0) return th - M_PI;
	else return -th;

}

double u_y(double x, double y) {
	double r = sqrt(pow(x, 2) + pow(y, 2));
	double th = th_p(x, y, atan(fabs(y / x)));

	return sqrt(r) * sin(th / 2);
}

void bound_set_embedded(double *bound, const graph_t *g, double notch_len) {
	uint_t L = g->L;

	for (uint_t i = 0; i < L / 2; i++) {
		double x1, y1, x2, y2, x3, y3, x4, y4;
		x1 = (2. * i + 1.) / L - notch_len; y1 = 0.5 - 1.;
		x2 = (2. * i + 1.) / L - notch_len; y2 = 0.5 - 0.;
		y3 = (2. * i + 1.) / L - 0.5; x3 = 0.5 - 1.;
		y4 = (2. * i + 1.) / L - 0.5; x4 = 0.5 - 0.;

		bound[g->bound_verts[g->bound_inds[0] + i]] = u_y(x1, y1);
		bound[g->bound_verts[g->bound_inds[1] + i]] = u_y(x2, y2);
		bound[g->bound_verts[g->bound_inds[2] + i]] = u_y(x3, y3);
		bound[g->bound_verts[g->bound_inds[3] + i]] = u_y(x4, y4);
	}
}

cholmod_dense *bound_set(const graph_t *g, bool vb, double notch_len, cholmod_common *c) {
	cholmod_dense *boundary = CHOL_F(zeros)(g->break_dim, 1, CHOLMOD_REAL, c);
	double *bound = (double *)boundary->x;

	switch (g->boundary) {
		case TORUS_BOUND:
			for (uint_t i = 0; i < g->bound_inds[1]; i++) {
				bound[g->bound_verts[i]] = 1;
				bound[g->nv + i] = -1;
			}
			bound[g->bound_verts[0]] = 1;
			break;
		case EMBEDDED_BOUND:
			bound_set_embedded(bound, g, notch_len);
			break;
		default:
			if (vb) {
				for (uint_t i = 0; i < g->bound_inds[1]; i++) {
					bound[g->bound_verts[i]] = 1;
				}
			} else {
				bound[0] = 1;
				bound[g->nv] = 1;
				bound[g->nv + 1] = -1;
			}
	}

	return boundary;
}