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/**

 * Copyright (c) 2011 Colony Project

 * 

 * Permission is hereby granted, free of charge, to any person

 * obtaining a copy of this software and associated documentation

 * files (the "Software"), to deal in the Software without

 * restriction, including without limitation the rights to use,

 * copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following

 * conditions:

 * 

 * The above copyright notice and this permission notice shall be

 * included in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

 * OTHER DEALINGS IN THE SOFTWARE.

 **/

/**

 * @file SonarControl.cpp

 * @brief Contains sonar function imeplementations

 * 

 * Contains functions for the use of sonar control.

 *

 * @author Colony Project, CMU Robotics Club

 * @author Priyanka Deo

 **/

#include "SonarControl.h"

/**

 * @brief Initialize the sonar module of libscout.

 *

 * Initialize the libscout node as a publisher of sonar_set_scan and 

 * sonar_toggle and a client of query_sonar.

 */

SonarControl::SonarControl(const ros::NodeHandle& libscout_node)

    : node(libscout_node)

{

    sonar_set_scan_pub =

        node.advertise<sonar::sonar_set_scan>("set_sonar_scan", QUEUE_SIZE);

    sonar_toggle_pub = 

        node.advertise<sonar::sonar_toggle>("toggle_sonar", QUEUE_SIZE);

    query_sonar =

        node.serviceClient<sonar::sonar_direction>("query_sonar");

}

/**

 * @brief Sets the sonar to a position.

 *

 * @param position Value between 0-180 of degree position to set sonar

 * @return NONE

 */

void SonarControl::set(int position)

{

    set_range(position, position);

}

/**

 * @brief Sets the sonar to scan between two positions

 *

 * @param start_pos The leftmost (smallest) value that the sonar can take

 * @param end_pos The rightmost (largest) value that the sonar can take

 * @return NONE

 */

void SonarControl::set_range(int start_pos, int end_pos)

{

    //TODO Enable some checks of start and end position

    sonar::sonar_set_scan msg;

    msg.stop_l = start_pos;

    msg.stop_r = end_pos;

    sonar_set_scan_pub.publish(msg);

    ros::spinOnce();

}

/**

 * @brief Query the current front sonar readings

 *

 * Sends a request to the query_sonar service which will reply with the

 *  current readings of the sonar.

 *

 * @TODO Change so we can get multiple sonar readings with one call

 *

 * @return The reading of the front sonar or LIB_ERR.

 */

float SonarControl::query_front()

{

    sonar::sonar_direction srv;

    if(query_sonar.call(srv))

    {

        srv.response.distance0;

    }

    else

    {

        ROS_ERROR("Failed to call service query_motors");

        return LIB_ERROR;

    }

    return 0;

}

/**

 * @brief Query the current back sonar readings

 *

 * Sends a request to the query_sonar service which will reply with the

 *  current readings of the sonar.

 *

 * @TODO Change so we can get multiple sonar readings with one call

 *

 * @return The reading of the back sonar or LIB_ERR.

 */

float SonarControl::query_back()

{

    sonar::sonar_direction srv;

    if(query_sonar.call(srv))

    {

        srv.response.distance1;

    }

    else

    {

        ROS_ERROR("Failed to call service query_motors");

        return LIB_ERROR;

    }

    return 0;

}

/**

 * @brief Converts value returne by sonar to physical distances.

 *

 * @param sonar_value The returned value of the sonar

 * @return The physical distance measured by the sonar.

 **/

float sonar_to_dist(float sonar_value)

{

    //TODO impelement later based on sonar readings

    return sonar_value;

}

/**

 * @brief Converts values from physical distances to values read by sonar

 *

 * @param distance The physical distance as measured.

 * @return The value read by the sonar that corresponds to the given distance

 **/

float dist_to_sonar(float distance)

{

    //TODO implement later based on sonar readings

    return distance;

}