/* *******************************************************************
 *  Includes
 * ******************************************************************/

#include "Camera.h"
#include <stdint.h>

/* *******************************************************************
 *  Defines
 * ******************************************************************/

#define MAX_CAMERA_SPEED        ((int8_t)3)
#define SPEED_CALCULATION_TIME  ((uint8_t)3)
#define CAMERA_ACCELERATION     ((int8_t)1)

/* *******************************************************************
 *  Types definition
 * ******************************************************************/

/* *******************************************************************
 *  Global variables definition
 * ******************************************************************/

/* *******************************************************************
 *  Local variables definition
 * ******************************************************************/

/* *******************************************************************
 *  Local prototypes declaration
 * ******************************************************************/

/* *******************************************************************
 *  Functions definition
 * ******************************************************************/

/*****************************************************************//**
 *
 * \brief   Constructor for Camera class.
 *
 *********************************************************************/
Camera::Camera(void) :
    _bLocked(false),
    _xOffset(0),
    _yOffset(0),
    _xSpeed(0),
    _ySpeed(0),
    _speedTimer(0)
{
}

void Camera::handler(void)
{
    _xOffset += _xSpeed;
    _yOffset += _ySpeed;

    if (++_speedTimer >= SPEED_CALCULATION_TIME)
    {
        _speedTimer = 0;

        if (_ySpeed < 0)
        {
            _ySpeed += CAMERA_ACCELERATION;
        }
        else if (_ySpeed > 0)
        {
            _ySpeed -= CAMERA_ACCELERATION;
        }
        else
        {
            /* Y speed is already still. Continue. */
        }

        if (_xSpeed < 0)
        {
            _xSpeed += CAMERA_ACCELERATION;
        }
        else if (_xSpeed > 0)
        {
            _xSpeed -= CAMERA_ACCELERATION;
        }
        else
        {
            /* x speed is alreadx still. Continue. */
        }
    }
}

/*****************************************************************//**
 *
 * \brief   This function transforms X coordinates for a given
 *          object to camera coordinates.
 *
 *********************************************************************/
uint8_t Camera::getX(const uint8_t x) const
{
    return x + _xOffset;
}

/*****************************************************************//**
 *
 * \brief   This function transforms Y coordinates for a given
 *          object to camera coordinates.
 *
 *********************************************************************/
uint8_t Camera::getY(const uint8_t y) const
{
    return y + _yOffset;
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          left arrow button.
 *
 *********************************************************************/
void Camera::onLeftBtnPressed(void)
{
    if (_xSpeed < 0)
    {
        _xSpeed += CAMERA_ACCELERATION << 1;
    }
    else if (_xSpeed < MAX_CAMERA_SPEED)
    {
        _xSpeed += CAMERA_ACCELERATION;
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          right arrow button.
 *
 *********************************************************************/
void Camera::onRightBtnPressed(void)
{
    if (_xSpeed > 0)
    {
        _xSpeed -= CAMERA_ACCELERATION << 1;
    }
    else if (_xSpeed > -MAX_CAMERA_SPEED)
    {
        _xSpeed -= CAMERA_ACCELERATION;
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          up arrow button.
 *
 *********************************************************************/
void Camera::onUpBtnPressed(void)
{
    if (_ySpeed < 0)
    {
        _ySpeed += CAMERA_ACCELERATION << 1;
    }
    else if (_ySpeed < MAX_CAMERA_SPEED)
    {
        _ySpeed += CAMERA_ACCELERATION;
    }
}

/*****************************************************************//**
 *
 * \brief   Event handler executed when human player presses
 *          down arrow button.
 *
 *********************************************************************/
void Camera::onDownBtnPressed(void)
{
    if (_ySpeed > 0)
    {
        _ySpeed -= CAMERA_ACCELERATION << 1;
    }
    else if (_ySpeed < MAX_CAMERA_SPEED)
    {
        _ySpeed -= CAMERA_ACCELERATION;
    }
}