/*
 * estimatepaths.c: Basic 'C' template for a level 2 S-function.
 * x(n+1)=u(n) 
 * y(n)  =f(x(n),u(n))
 * Copyright 2008.4.28 vincent.
 * $Revision: 0.1
 */

#define S_FUNCTION_NAME  estimatepaths
#define S_FUNCTION_LEVEL 2


#include "simstruc.h"
#include <stdlib.h>

/*--------------------------------------------------------------*/
static void mdlInitializeSizes(SimStruct *S)
{
   
    ssSetNumSFcnParams(S, 0);       /* Number of expected parameters */
    if (ssGetNumSFcnParams(S) != ssGetSFcnParamsCount(S)) {
                                    /* Return if number of expected != number of actual parameters */
        return;
    }

    ssSetNumContStates(S, 0);
    ssSetNumDiscStates(S, 1);

    if (!ssSetNumInputPorts(S, 2)) return;
    ssSetInputPortWidth(S, 0, 1);
    ssSetInputPortDirectFeedThrough(S, 0, 0);

	
	ssSetInputPortWidth(S, 1, 1);
    ssSetInputPortDirectFeedThrough(S, 1, 1);

    if (!ssSetNumOutputPorts(S, 2)) return;
    ssSetOutputPortWidth(S, 0, 1);
    ssSetOutputPortWidth(S, 1, 1);
    
    ssSetNumSampleTimes(S, 1);

    ssSetNumRWork(S, 2);
    ssSetNumIWork(S, 0);
    ssSetNumPWork(S, 0);
    ssSetNumModes(S, 0);
    ssSetNumNonsampledZCs(S, 0);

    ssSetOptions(S,SS_OPTION_EXCEPTION_FREE_CODE);
}

/*----------------------------------------------------------*/

static void mdlInitializeSampleTimes(SimStruct *S)
{
    ssSetSampleTime(S, 0, INHERITED_SAMPLE_TIME);
    ssSetOffsetTime(S, 0, 0.0);
   
}

/*-----------------------------------------------------------*/
#define MDL_INITIALIZE_CONDITIONS
/* Function: mdlInitializeConditions ========================================
 * Abstract:
 *    Initialize both discrete states to one.
 */
static void mdlInitializeConditions(SimStruct *S)
{
    real_T *x  = ssGetRealDiscStates(S);
    *x         =0.0;
}

/*----------------------------------------------------------------*/
static void mdlOutputs(SimStruct *S, int_T tid)
{
	real_T      teamp_v;
	real_T      teamp_u;
	real_T      teamp;
	real_T            *y_0    = ssGetOutputPortRealSignal(S,0);
	real_T            *y_1    = ssGetOutputPortRealSignal(S,1);

    real_T            *x    = ssGetRealDiscStates(S);
    InputRealPtrsType vPtrs = ssGetInputPortRealSignalPtrs(S,0);
    InputRealPtrsType uPtrs = ssGetInputPortRealSignalPtrs(S,1);
    UNUSED_ARG(tid);
      
     teamp    =   *x;
     teamp_v  =   *vPtrs[0];
	 teamp_u  =   *uPtrs[0];

    if((teamp_v>0.0)&&((teamp_v-teamp_u)>=-1)&&((teamp_v-teamp_u)<=1))
	{   
      
			*y_0= teamp_v;
			*y_1= teamp_u;
	
	}
	else
	{  
		*y_0= 0.0;
		*y_1= 0.0;
	}
   
}


/*--------------------------------------------------------*/
#define MDL_UPDATE  /* Change to #undef to remove function */
#if defined(MDL_UPDATE)

  static void mdlUpdate(SimStruct *S, int_T tid)
  {   
	 
	  real_T                *x              = ssGetRealDiscStates(S);
	  InputRealPtrsType		uPtrs			= ssGetInputPortRealSignalPtrs(S,1);
     
	  UNUSED_ARG(tid);
    
		  *x=*uPtrs[0];
	
  }
#endif /* MDL_UPDATE */
/*----------------------------------------------------------------------------------*/


#undef MDL_DERIVATIVES  /* Change to #undef to remove function */
#if defined(MDL_DERIVATIVES)
  /* Function: mdlDerivatives =================================================
   * Abstract:
   *    In this function, you compute the S-function block's derivatives.
   *    The derivatives are placed in the derivative vector, ssGetdX(S).
   */
  static void mdlDerivatives(SimStruct *S)
  {
  }
#endif /* MDL_DERIVATIVES */



/* Function: mdlTerminate =====================================================
 */
static void mdlTerminate(SimStruct *S)
{
}

#ifdef  MATLAB_MEX_FILE    /* Is this file being compiled as a MEX-file? */
#include "simulink.c"      /* MEX-file interface mechanism */
#else
#include "cg_sfun.h"       /* Code generation registration function */
#endif