/*
 * rt_zcfcn.cpp
 *
 * Academic License - for use in teaching, academic research, and meeting
 * course requirements at degree granting institutions only.  Not for
 * government, commercial, or other organizational use.
 *
 * Code generation for model "Alinear_encoder".
 *
 * Model version              : 1.3
 * Simulink Coder version : 24.2 (R2024b) 21-Jun-2024
 * C++ source code generated on : Fri Aug 22 11:49:38 2025
 *
 * Target selection: speedgoat.tlc
 * Note: GRT includes extra infrastructure and instrumentation for prototyping
 * Embedded hardware selection: Intel->x86-64 (Linux 64)
 * Code generation objectives: Unspecified
 * Validation result: Not run
 */

#include "zero_crossing_types.h"
#include "rtwtypes.h"
#include "rt_zcfcn.h"
#include "solver_zc.h"

extern "C"
{
  /* Detect zero crossings events. */
  ZCEventType rt_ZCFcn(ZCDirection zcDir, ZCSigState *prevZc, real_T currValue)
  {
    slZcEventType zcsDir;
    slZcEventType tempEv;
    ZCEventType zcEvent = NO_ZCEVENT;  /* assume */

    /* zcEvent matrix */
    static const slZcEventType eventMatrix[4][4] = {
      /*          ZER              POS              NEG              UNK */
      { SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_Z2P, SL_ZCS_EVENT_Z2N, SL_ZCS_EVENT_NUL },/* ZER */

      { SL_ZCS_EVENT_P2Z, SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_P2N, SL_ZCS_EVENT_NUL },/* POS */

      { SL_ZCS_EVENT_N2Z, SL_ZCS_EVENT_N2P, SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_NUL },/* NEG */

      { SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_NUL, SL_ZCS_EVENT_NUL }/* UNK */
    };

    /* get prevZcEvent and prevZcSign from prevZc */
    const slZcEventType prevEv = (slZcEventType)(((uint8_T)(*prevZc)) >> 2);
    const slZcSignalSignType prevSign = (slZcSignalSignType)(((uint8_T)(*prevZc))
      & (uint8_T)0x03);

    /* get current zcSignal sign from current zcSignal value */
    const slZcSignalSignType currSign = (slZcSignalSignType)((currValue) > 0.0 ?
      SL_ZCS_SIGN_POS :
      ((currValue) < 0.0 ? SL_ZCS_SIGN_NEG : SL_ZCS_SIGN_ZERO));

    /* get current zcEvent based on prev and current zcSignal value */
    slZcEventType currEv = eventMatrix[prevSign][currSign];

    /* get slZcEventType from ZCDirection */
    switch (zcDir) {
     case ANY_ZERO_CROSSING:
      zcsDir = SL_ZCS_EVENT_ALL;
      break;

     case FALLING_ZERO_CROSSING:
      zcsDir = SL_ZCS_EVENT_ALL_DN;
      break;

     case RISING_ZERO_CROSSING:
      zcsDir = SL_ZCS_EVENT_ALL_UP;
      break;

     default:
      zcsDir = SL_ZCS_EVENT_NUL;
      break;
    }

    /* had event, check if zc happened */
    if (slZcHadEvent(currEv, zcsDir)) {
      currEv = (slZcEventType)(slZcUnAliasEvents(prevEv, currEv));
    } else {
      currEv = SL_ZCS_EVENT_NUL;
    }

    /* Update prevZc */
    tempEv = (slZcEventType)(currEv << 2);/* shift left by 2 bits */
    *prevZc = (ZCSigState)((currSign) | (tempEv));
    if ((currEv & SL_ZCS_EVENT_ALL_DN) != 0) {
      zcEvent = FALLING_ZCEVENT;
    } else if ((currEv & SL_ZCS_EVENT_ALL_UP) != 0) {
      zcEvent = RISING_ZCEVENT;
    } else {
      zcEvent = NO_ZCEVENT;
    }

    return zcEvent;
  }                                    /* rt_ZCFcn */
}