/**********************************************************************//**
 *
 *  Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
 *
 *  THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 *  WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
 *  @file Timers.c
 *
 *  @date 25-Sep-2019
 *  @author S. Nash
 *
 *  @brief Timers service module.  Provides miscellaneous timer functions.
 *
 **************************************************************************/

#include "Timers.h"

/**
 *  @addtogroup Timers
 *  @{
 */

// ********** private definitions **********

// ********** private data **********

static U32 msTimerCount = 0;            ///< 1ms timer counter incremented by TaskTimer.c.

/*********************************************************************//**
 * @brief
 * The initTimers function initializes the Timers module.
 * @details
 * Inputs : none
 * Outputs : Timers module initialized.
 * @return none
 *************************************************************************/
void initTimers( void )
{
    msTimerCount = 0;
}

/*********************************************************************//**
 * @brief
 * The incMSTimerCount function increments the ms timer count.
 * @details
 * Inputs : none
 * Outputs : msTimerCount incremented
 * @return none
 *************************************************************************/
void incMSTimerCount( void )
{
    msTimerCount++;
}

/*********************************************************************//**
 * @brief
 * The getMSTimerCount function returns the current ms timer count.
 * @details
 * Inputs : msTimerCount
 * Outputs : none
 * @return msTimerCount
 *************************************************************************/
U32 getMSTimerCount( void )
{
    return msTimerCount;
}

/*********************************************************************//**
 * @brief
 * The didTimeout function determines whether a timeout has occurred between \n
 * a given start count and a given timeout period (in ms).
 * @details
 * Inputs : msTimerCount
 * Outputs : none
 * @param startMSCount : the ms count at the start of the timeout period
 * @param timeoutPeriod : the period for the timeout (in ms)
 * @return TRUE if a timeout has occurred, FALSE if not
 *************************************************************************/
BOOL didTimeout( U32 startMSCount, U32 timeoutPeriod )
{
    BOOL result = FALSE;
    U32  currMSCount = msTimerCount;

    // no wrap
    if ( currMSCount >= startMSCount )
    {
        if ( ( currMSCount - startMSCount ) >= timeoutPeriod )
        {
            result = TRUE;
        }
    }
    // counter wrapped
    else
    {
        U32 deltaMSCount = ( 0xFFFFFFFF - startMSCount ) + currMSCount + 1;

        if ( deltaMSCount >= timeoutPeriod )
        {
            result = TRUE;
        }
    }

    return result;
}

/*********************************************************************//**
 * @brief
 * The calcTimeSince function calculates the time (in ms) from a given start \n
 * time until now.
 * @details
 * Inputs : msTimerCount
 * Outputs : none
 * @param startMSCount : the ms count at the start of the period
 * @return ms since given start time
 *************************************************************************/
U32 calcTimeSince( U32 startMSCount )
{
    U32 result;
    U32 currMSCount = msTimerCount;

    // no wrap
    if ( currMSCount >= startMSCount )
    {
        result = currMSCount - startMSCount;
    }
    else
    {
        result = ( 0xFFFFFFFF - startMSCount ) + currMSCount + 1;
    }

    return result;
}

/*********************************************************************//**
 * @brief
 * The calcTimeBetween function calculates the time (in ms) from a given start \n
 * time until a given end time.
 * @details
 * Inputs : none
 * Outputs : none
 * @param startMSCount : the ms count at the start of the period
 * @param endMSCount : the ms count at the end of the period
 * @return ms between two given times
 *************************************************************************/
U32 calcTimeBetween( U32 startMSCount, U32 endMSCount )
{
    U32 result;

    // no wrap
    if ( endMSCount >= startMSCount )
    {
        result = endMSCount - startMSCount;
    }
    else
    {
        result = ( 0xFFFFFFFF - startMSCount ) + endMSCount + 1;
    }

    return result;
}

/**@}*/