#include "control.h"

#include <math.h>
#include <stdlib.h>
#include <assert.h>

struct angle {
	double a;
	int c;
};
typedef struct angle angle;

gint cmp_angle(gconstpointer _a, gconstpointer _b, gpointer p) {
	const angle *a = (const angle*) _a, *b = (const angle*) _b;
	UNUSED(p);
	return (a->a == b->a) ? 0 : (a->a < b->a) ? -1 : 1;
}

void angle_free(angle* a) {
	g_slice_free(angle, a);
}

angle* angle_new(double a, int c) {
	angle *x = g_slice_new(angle);
	x->a = a; x->c = c;
	return x;
}

static double fixangle(double a) {
	while (a < -180) a += 360;
	while (a > 180) a -= 360;
	return a;
}

void goradar(trial *t) {
	vehicle v;
	telemetry *tm;
	GSequence *angles = g_sequence_new((GDestroyNotify) angle_free);
	GSequenceIter *prev, *cur, *end;
	angle *acur, *aprev;
	double hang, ang = 1000, weight = 0;
	int c;
	guint i;

	v = t->sim.tm.vehicle;
	hang = atan2(-v.y, -v.x)*180/M_PI;
	
	tm = &t->sim.tm;

	g_sequence_insert_sorted(angles, angle_new(-45, 0), cmp_angle, NULL);
	g_sequence_insert_sorted(angles, angle_new(45, 0), cmp_angle, NULL);
	for (i = 0; i < tm->objects->len; i++) {
		object *o = &g_array_index(tm->objects, object, i);
		double phi, phi2, avoid = 0, oangle;
		double distance = sqrt((o->y - v.y) * (o->y - v.y) + (o->x - v.x) * (o->x - v.x));
		oangle = fixangle(atan2(-o->y, -o->x)*180/M_PI - hang);
		if (fabs(oangle) > 180) continue;
// 		if (distance > 100) continue;
		phi = fixangle(atan2(o->y - v.y, o->x - v.x)*180/M_PI - hang);
		if (fabs(phi) > 45) continue;
		switch (o->type) {
			case BOLDER:
				avoid = 1.2 * o->rad + VEHICLE_RADIUS; break;
			case CRATER:
				avoid = 1.2 * o->rad + VEHICLE_RADIUS + 1; break;
			case MARTIAN:
				avoid = o->rad + VEHICLE_RADIUS + 5; break;
		}
		phi2 = atan(avoid / distance )*180/M_PI;
		g_sequence_insert_sorted(angles, angle_new(phi - phi2, 1), cmp_angle, NULL);
		g_sequence_insert_sorted(angles, angle_new(phi + phi2, -1), cmp_angle, NULL);
	}

	prev = g_sequence_get_begin_iter(angles), end = g_sequence_get_end_iter(angles);
	if (prev != end) {
		aprev = (angle*) g_sequence_get(prev);
		c = aprev->c;
		while ((cur = g_sequence_iter_next(prev)) != end) {
			acur = (angle*) g_sequence_get(cur);
			assert(aprev->a <= acur->a);
			if (!c) {
// 				fprintf(stderr, "Gap between %f and %f\n", aprev->a, acur->a);
				if (acur->a - aprev->a > 1) {
					double ax, ad, w1 = 1E20, w2 = 1E20, w;
					if (aprev->a <= 0) {
						if (acur->a <= 0) {
							ax = acur->a;
						} else {
							ax = 0;
						}
					} else {
						ax = aprev->a;
					}
					if (ax != 0) w1 = 1/fabs(ax);
					ad = fixangle(ax - v.dir + hang);
					if (ad != 0) w2 = 1/fabs(ad);
					w = w1+w2;
					if (w > weight) {
						fprintf(stderr, "Selected %f\n", ax);
						ang = ax;
						weight = w;
					}
				}
			}
			
			c += acur->c;
			prev = cur;
			aprev = acur;
		}
	}

	if (weight == 0) {
		fprintf(stderr, "Potential\n");
		godown(t);
		return;
	}

	ang = fixangle(ang - v.dir + hang);
	fprintf(stderr, "Angle: %f, objects: %u\n", ang, tm->objects->len);
	if (ang < 1) {
		if (ang < -50) {
			vehicle_hard_right(t);
		} else {
			vehicle_right(t);
		}
	} else if (ang > 1) {
		if (ang > 50) {
			vehicle_hard_left(t);
		} else {
			vehicle_left(t);
		}
	}
	ang = fabs(ang);
	if (ang > 90) {
		vehicle_break(t);
	} else if (ang > 45) {
		vehicle_roll(t);
	} else {
		vehicle_accel(t);
	}
}