/*************************************************************************\
* Copyright (c) 2002 The University of Chicago, as Operator of Argonne
*     National Laboratory.
* Copyright (c) 2002 The Regents of the University of California, as
*     Operator of Los Alamos National Laboratory.
* EPICS BASE Versions 3.13.7
* and higher are distributed subject to a Software License Agreement found
* in file LICENSE that is included with this distribution. 
\*************************************************************************/

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

#include "exServer.h"
#include "gddApps.h"

#define myPI 3.14159265358979323846

//
// SUN C++ does not have RAND_MAX yet
//
#if !defined(RAND_MAX)
//
// Apparently SUN C++ is using the SYSV version of rand
//
#if 0
#define RAND_MAX INT_MAX
#else
#define RAND_MAX SHRT_MAX
#endif
#endif

//
// exScalarPV::scan
//
void exScalarPV::scan()
{
    caStatus        status;
    double          radians;
    smartGDDPointer pDD;
    float           newValue;
    float           limit;
    int             gddStatus;

    //
    // update current time (so we are not required to do
    // this every time that we write the PV which impacts
    // throughput under sunos4 because gettimeofday() is
    // slow)
    //
    this->currentTime = epicsTime::getCurrent ();

    pDD = new gddScalar ( gddAppType_value, aitEnumFloat64 );
    if ( ! pDD.valid () ) {
        return;
    }

    //
    // smart pointer class manages reference count after this point
    //
    gddStatus = pDD->unreference ();
    assert ( ! gddStatus );

    radians = ( rand () * 2.0 * myPI ) / RAND_MAX;
    if ( this->pValue.valid () ) {
        this->pValue->getConvert(newValue);
    }
    else {
        newValue = 0.0f;
    }
    newValue += (float) ( sin (radians) / 10.0 );
    limit = (float) this->info.getHopr ();
    newValue = tsMin ( newValue, limit );
    limit = (float) this->info.getLopr ();
    newValue = tsMax ( newValue, limit );
    *pDD = newValue;
    aitTimeStamp gddts ( this->currentTime );
    pDD->setTimeStamp ( & gddts );
    status = this->update ( *pDD );
    if (status!=S_casApp_success) {
        errMessage ( status, "scalar scan update failed\n" );
    }
}

//
// exScalarPV::updateValue ()
//
// NOTES:
// 1) This should have a test which verifies that the 
// incoming value in all of its various data types can
// be translated into a real number?
// 2) We prefer to unreference the old PV value here and
// reference the incomming value because this will
// result in each value change events retaining an
// independent value on the event queue.
//
caStatus exScalarPV::updateValue ( const gdd & valueIn )
{
    //
    // Really no need to perform this check since the
    // server lib verifies that all requests are in range
    //
    if ( ! valueIn.isScalar() ) {
        return S_casApp_outOfBounds;
    }

    if ( ! pValue.valid () ) {
        this->pValue = new gddScalar ( 
            gddAppType_value, this->info.getType () );
        if ( ! pValue.valid () ) {
            return S_casApp_noMemory;
        }
    }

    this->pValue->put ( & valueIn );

    return S_casApp_success;
}