#include "gsai_arrive.h"

GSAIAgentLocation GSAIArrive::get_ *target() {
	return *target;
}

void GSAIArrive::set_ *target(const GSAIAgentLocation &val) {
	*target = val;
}

float GSAIArrive::get_arrival_tolerance() const {
	return arrival_tolerance;
}

void GSAIArrive::set_arrival_tolerance(const float val) {
	arrival_tolerance = val;
}

float GSAIArrive::get_deceleration_radius() const {
	return deceleration_radius;
}

void GSAIArrive::set_deceleration_radius(const float val) {
	deceleration_radius = val;
}

float GSAIArrive::get_time_to_reach() const {
	return time_to_reach;
}

void GSAIArrive::set_time_to_reach(const float val) {
	time_to_reach = val;
}

// Calculates acceleration to take an agent to its target's location. The;
// calculation attempts to arrive with zero remaining velocity.;
// @category - Individual behaviors;
// Target agent to arrive to.;
GSAIAgentLocation *target;
// Distance from the target for the agent to be considered successfully;
// arrived.;
float arrival_tolerance = 0.0;
// Distance from the target for the agent to begin slowing down.;
float deceleration_radius = 0.0;
// Represents the time it takes to change acceleration.;
float time_to_reach = 0.1;

void GSAIArrive::arrive(const GSAITargetAcceleration &acceleration, const Vector3 &target_position) {
	call("_arrive", acceleration, target_position);
}

void GSAIArrive::_arrive(const GSAITargetAcceleration &acceleration, const Vector3 &target_position) {
	Vector3 to_target = target_position - agent.position;
	float distance = to_target.length();

	if (distance <= arrival_tolerance) {
		acceleration.set_zero();
	}

	else {
		float desired_speed = agent.linear_speed_max;

		if (distance <= deceleration_radius) {
			desired_speed *= distance / deceleration_radius;
		}

		Vector3 desired_velocity = to_target * desired_speed / distance;
		desired_velocity = ((desired_velocity - agent.linear_velocity) * 1.0 / time_to_reach);
		acceleration.linear = GSAIUtils.clampedv3(desired_velocity, agent.linear_acceleration_max);
		acceleration.angular = 0;
	}
}

void GSAIArrive::_calculate_steering(const GSAITargetAcceleration &acceleration) {
	arrive(acceleration, target.position);
}
}

GSAIArrive::GSAIArrive() {
	*target;
	arrival_tolerance = 0.0;
	deceleration_radius = 0.0;
	time_to_reach = 0.1;
}

GSAIArrive::~GSAIArrive() {
}

static void GSAIArrive::_bind_methods() {
	ClassDB::bind_method(D_METHOD("get_*target"), &GSAIArrive::get_ * target);
	ClassDB::bind_method(D_METHOD("set_*target", "value"), &GSAIArrive::set_ * target);
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "*target", PROPERTY_HINT_RESOURCE_TYPE, "GSAIAgentLocation"), "set_*target", "get_*target");

	ClassDB::bind_method(D_METHOD("get_arrival_tolerance"), &GSAIArrive::get_arrival_tolerance);
	ClassDB::bind_method(D_METHOD("set_arrival_tolerance", "value"), &GSAIArrive::set_arrival_tolerance);
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "arrival_tolerance"), "set_arrival_tolerance", "get_arrival_tolerance");

	ClassDB::bind_method(D_METHOD("get_deceleration_radius"), &GSAIArrive::get_deceleration_radius);
	ClassDB::bind_method(D_METHOD("set_deceleration_radius", "value"), &GSAIArrive::set_deceleration_radius);
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "deceleration_radius"), "set_deceleration_radius", "get_deceleration_radius");

	ClassDB::bind_method(D_METHOD("get_time_to_reach"), &GSAIArrive::get_time_to_reach);
	ClassDB::bind_method(D_METHOD("set_time_to_reach", "value"), &GSAIArrive::set_time_to_reach);
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "time_to_reach"), "set_time_to_reach", "get_time_to_reach");

	ClassDB::bind_method(D_METHOD("arrive", "acceleration", "target_position"), &GSAIArrive::arrive);
	ClassDB::bind_method(D_METHOD("_arrive", "acceleration", "target_position"), &GSAIArrive::_arrive);
	ClassDB::bind_method(D_METHOD("_calculate_steering", "acceleration"), &GSAIArrive::_calculate_steering);
}