/* TA-LIB Copyright (c) 1999-2025, Mario Fortier
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
*   notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
*   notice, this list of conditions and the following disclaimer in
*   the documentation and/or other materials provided with the
*   distribution.
*
* - Neither name of author nor the names of its contributors
*   may be used to endorse or promote products derived from this
*   software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/* AUTO-GENERATED by ta_codegen — DO NOT EDIT.
* Source of truth: ta_codegen/input/<name>/  (regenerate: cd ta_codegen/generator && cargo run -- generate)
*/

#include <string.h>
#include <math.h>
#include "ta_func.h"
#include "ta_utility.h"
#include "ta_memory.h"
#include "ta_func_unguarded.h"

/* List of contributors:
 *
 *  Initial  Name/description
 *  -------------------------------------------------------------------
 *  MF       Mario Fortier
 *  CF       Christo Fogelberg
 *
 * Change history:
 *
 *  MMDDYY BY     Description
 *  -------------------------------------------------------------------
 *  010802 MF     Template creation.
 *  052603 MF     Adapt code to compile with .NET Managed C++
 *  122104 MF,CF  Fix#1089506 for out-of-bound access to ep_temp.
 */

TA_LIB_API int TA_SAR_Lookback( double optInAcceleration, double optInMaximum )
{
   if( optInAcceleration == -4e37 )
      optInAcceleration = 0.02;
   else if( optInAcceleration < 0e0 || optInAcceleration > 1.7976931348623157e308 )
      return -1;
   if( optInMaximum == -4e37 )
      optInMaximum = 0.2;
   else if( optInMaximum < 0e0 || optInMaximum > 1.7976931348623157e308 )
      return -1;
   /* SAR always sacrify one price bar to establish the
    * initial extreme price.
    */
   return 1;
}

TA_LIB_API TA_RetCode TA_SAR( int    startIdx,
                              int    endIdx,
                              const double inHigh[],
                              const double inLow[],
                              double optInAcceleration,
                              double optInMaximum,
                              int          *outBegIdx,
                              int          *outNBElement,
                              double        outReal[] )
{
   TA_RetCode retCode;
   int isLong;
   int todayIdx;
   int outIdx;
   int tempInt;
   double newHigh;
   double newLow;
   double prevHigh;
   double prevLow;
   double af;
   double ep;
   double sar;
   double ep_temp[1];

   if( startIdx < 0 )
      return TA_OUT_OF_RANGE_START_INDEX;
   if( (endIdx < 0) || (endIdx < startIdx) )
      return TA_OUT_OF_RANGE_END_INDEX;

   if( !inHigh )
      return TA_BAD_PARAM;
   if( !inLow )
      return TA_BAD_PARAM;
   if( optInAcceleration == -4e37 )
      optInAcceleration = 0.02;
   else if( optInAcceleration < 0e0 || optInAcceleration > 1.7976931348623157e308 )
      return TA_BAD_PARAM;
   if( optInMaximum == -4e37 )
      optInMaximum = 0.2;
   else if( optInMaximum < 0e0 || optInMaximum > 1.7976931348623157e308 )
      return TA_BAD_PARAM;
   if( !outReal )
      return TA_BAD_PARAM;

   /* > 0 indicates long. == 0 indicates short */
   /* Implementation of the SAR has been a little bit open to interpretation
    * since Wilder (the original author) did not define a precise algorithm
    * on how to bootstrap the algorithm. Take any existing software application
    * and you will see slight variation on how the algorithm was adapted.
    *
    * What is the initial trade direction? Long or short?
    * ===================================================
    * The interpretation of what should be the initial SAR values is
    * open to interpretation, particularly since the caller to the function
    * does not specify the initial direction of the trade.
    *
    * In TA-Lib, the following logic is used:
    *  - Calculate +DM and -DM between the first and
    *    second bar. The highest directional indication will
    *    indicate the assumed direction of the trade for the second
    *    price bar.
    *  - In the case of a tie between +DM and -DM,
    *    the direction is LONG by default.
    *
    * What is the initial "extreme point" and thus SAR?
    * =================================================
    * The following shows how different people took different approach:
    *  - Metastock use the first price bar high/low depending of
    *    the direction. No SAR is calculated for the first price
    *    bar.
    *  - Tradestation use the closing price of the second bar. No
    *    SAR are calculated for the first price bar.
    *  - Wilder (the original author) use the SIP from the
    *    previous trade (cannot be implement here since the
    *    direction and length of the previous trade is unknonw).
    *  - The Magazine TASC seems to follow Wilder approach which
    *    is not practical here.
    *
    * TA-Lib "consume" the first price bar and use its high/low as the
    * initial SAR of the second price bar. I found that approach to be
    * the closest to Wilders idea of having the first entry day use
    * the previous extreme point, except that here the extreme point is
    * derived solely from the first price bar. I found the same approach
    * to be used by Metastock.
    */
   /* Identify the minimum number of price bar needed
    * to calculate at least one output.
    *
    * Move up the start index if there is not
    * enough initial data.
    */
   if( startIdx < 1 )
   {
      startIdx = 1;
   }
   /* Make sure there is still something to evaluate. */
   if( startIdx > endIdx )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return TA_SUCCESS;
   }
   /* Make sure the acceleration and maximum are coherent.
    * If not, correct the acceleration.
    */
   af = optInAcceleration;
   if( af > optInMaximum )
   {
      optInAcceleration = optInMaximum;
      af = optInAcceleration;
   }
   /* Identify if the initial direction is long or short.
    * (ep is just used as a temp buffer here, the name
    *  of the parameter is not significant).
    */
   retCode = TA_MINUS_DM_Unguarded(startIdx,startIdx,inHigh,inLow,1,&tempInt,&tempInt,ep_temp);
   if( ep_temp[0] > 0 )
   {
      isLong = 0;
   } else 
   {
      isLong = 1;
   }
   if( retCode != TA_SUCCESS )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return retCode;
   }
   *outBegIdx= startIdx;
   outIdx = 0;
   /* Write the first SAR. */
   todayIdx = startIdx;
   newHigh = inHigh[todayIdx - 1];
   newLow = inLow[todayIdx - 1];
   if( isLong == 1 )
   {
      ep = inHigh[todayIdx];
      sar = newLow;
   } else 
   {
      ep = inLow[todayIdx];
      sar = newHigh;
   }
   /* Cheat on the newLow and newHigh for the
    * first iteration.
    */
   newLow = inLow[todayIdx];
   newHigh = inHigh[todayIdx];
   while( todayIdx <= endIdx )
   {
      prevLow = newLow;
      prevHigh = newHigh;
      newLow = inLow[todayIdx];
      newHigh = inHigh[todayIdx];
      todayIdx += 1;
      if( isLong == 1 )
      {
         /* Switch to short if the low penetrates the SAR value. */
         if( newLow <= sar )
         {
            /* Switch and Overide the SAR with the ep */
            isLong = 0;
            sar = ep;
            /* Make sure the overide SAR is within
             * yesterday's and today's range.
             */
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
            /* Output the overide SAR */
            outReal[outIdx++] = sar;
            /* Adjust af and ep */
            af = optInAcceleration;
            ep = newLow;
            /* Calculate the new SAR */
            sar = sar + af * (ep - sar);
            /* Make sure the new SAR is within
             * yesterday's and today's range.
             */
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
         } else 
         {
            /* No switch */
            /* Output the SAR (was calculated in the previous iteration) */
            outReal[outIdx++] = sar;
            /* Adjust af and ep. */
            if( newHigh > ep )
            {
               ep = newHigh;
               af += optInAcceleration;
               if( af > optInMaximum )
               {
                  af = optInMaximum;
               }
            }
            /* Calculate the new SAR */
            sar = sar + af * (ep - sar);
            /* Make sure the new SAR is within
             * yesterday's and today's range.
             */
            if( sar > prevLow )
            {
               sar = prevLow;
            }
            if( sar > newLow )
            {
               sar = newLow;
            }
         }
      /* Switch to long if the high penetrates the SAR value. */
      } else if( newHigh >= sar )
      {
         /* Switch and Overide the SAR with the ep */
         isLong = 1;
         sar = ep;
         /* Make sure the overide SAR is within
          * yesterday's and today's range.
          */
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
         /* Output the overide SAR */
         outReal[outIdx++] = sar;
         /* Adjust af and ep */
         af = optInAcceleration;
         ep = newHigh;
         /* Calculate the new SAR */
         sar = sar + af * (ep - sar);
         /* Make sure the new SAR is within
          * yesterday's and today's range.
          */
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
      } else 
      {
         /* No switch */
         /* Output the SAR (was calculated in the previous iteration) */
         outReal[outIdx++] = sar;
         /* Adjust af and ep. */
         if( newLow < ep )
         {
            ep = newLow;
            af += optInAcceleration;
            if( af > optInMaximum )
            {
               af = optInMaximum;
            }
         }
         /* Calculate the new SAR */
         sar = sar + af * (ep - sar);
         /* Make sure the new SAR is within
          * yesterday's and today's range.
          */
         if( sar < prevHigh )
         {
            sar = prevHigh;
         }
         if( sar < newHigh )
         {
            sar = newHigh;
         }
      }
   }
   *outNBElement= outIdx;
   return TA_SUCCESS;
}

TA_LIB_API TA_RetCode TA_SAR_Unguarded( int    startIdx,
                                        int    endIdx,
                                        const double inHigh[],
                                        const double inLow[],
                                        double optInAcceleration,
                                        double optInMaximum,
                                        int          *outBegIdx,
                                        int          *outNBElement,
                                        double        outReal[] )
{
   TA_RetCode retCode;
   int isLong;
   int todayIdx;
   int outIdx;
   int tempInt;
   double newHigh;
   double newLow;
   double prevHigh;
   double prevLow;
   double af;
   double ep;
   double sar;
   double ep_temp[1];

   if( startIdx < 1 )
   {
      startIdx = 1;
   }
   if( startIdx > endIdx )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return TA_SUCCESS;
   }
   af = optInAcceleration;
   if( af > optInMaximum )
   {
      optInAcceleration = optInMaximum;
      af = optInAcceleration;
   }
   retCode = TA_MINUS_DM_Unguarded(startIdx,startIdx,inHigh,inLow,1,&tempInt,&tempInt,ep_temp);
   if( ep_temp[0] > 0 )
   {
      isLong = 0;
   } else 
   {
      isLong = 1;
   }
   if( retCode != TA_SUCCESS )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return retCode;
   }
   *outBegIdx= startIdx;
   outIdx = 0;
   todayIdx = startIdx;
   newHigh = inHigh[todayIdx - 1];
   newLow = inLow[todayIdx - 1];
   if( isLong == 1 )
   {
      ep = inHigh[todayIdx];
      sar = newLow;
   } else 
   {
      ep = inLow[todayIdx];
      sar = newHigh;
   }
   newLow = inLow[todayIdx];
   newHigh = inHigh[todayIdx];
   while( todayIdx <= endIdx )
   {
      prevLow = newLow;
      prevHigh = newHigh;
      newLow = inLow[todayIdx];
      newHigh = inHigh[todayIdx];
      todayIdx += 1;
      if( isLong == 1 )
      {
         if( newLow <= sar )
         {
            isLong = 0;
            sar = ep;
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
            outReal[outIdx++] = sar;
            af = optInAcceleration;
            ep = newLow;
            sar = sar + af * (ep - sar);
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
         } else 
         {
            outReal[outIdx++] = sar;
            if( newHigh > ep )
            {
               ep = newHigh;
               af += optInAcceleration;
               if( af > optInMaximum )
               {
                  af = optInMaximum;
               }
            }
            sar = sar + af * (ep - sar);
            if( sar > prevLow )
            {
               sar = prevLow;
            }
            if( sar > newLow )
            {
               sar = newLow;
            }
         }
      } else if( newHigh >= sar )
      {
         isLong = 1;
         sar = ep;
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
         outReal[outIdx++] = sar;
         af = optInAcceleration;
         ep = newHigh;
         sar = sar + af * (ep - sar);
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
      } else 
      {
         outReal[outIdx++] = sar;
         if( newLow < ep )
         {
            ep = newLow;
            af += optInAcceleration;
            if( af > optInMaximum )
            {
               af = optInMaximum;
            }
         }
         sar = sar + af * (ep - sar);
         if( sar < prevHigh )
         {
            sar = prevHigh;
         }
         if( sar < newHigh )
         {
            sar = newHigh;
         }
      }
   }
   *outNBElement= outIdx;
   return TA_SUCCESS;
}

TA_RetCode TA_S_SAR( int    startIdx,
                     int    endIdx,
                     const float inHigh[],
                     const float inLow[],
                     double optInAcceleration,
                     double optInMaximum,
                     int          *outBegIdx,
                     int          *outNBElement,
                     double        outReal[] )
{
   TA_RetCode retCode;
   int isLong;
   int todayIdx;
   int outIdx;
   int tempInt;
   double newHigh;
   double newLow;
   double prevHigh;
   double prevLow;
   double af;
   double ep;
   double sar;
   double ep_temp[1];

   if( startIdx < 0 )
      return TA_OUT_OF_RANGE_START_INDEX;
   if( (endIdx < 0) || (endIdx < startIdx) )
      return TA_OUT_OF_RANGE_END_INDEX;

   if( !inHigh )
      return TA_BAD_PARAM;
   if( !inLow )
      return TA_BAD_PARAM;
   if( optInAcceleration == -4e37 )
      optInAcceleration = 0.02;
   else if( optInAcceleration < 0e0 || optInAcceleration > 1.7976931348623157e308 )
      return TA_BAD_PARAM;
   if( optInMaximum == -4e37 )
      optInMaximum = 0.2;
   else if( optInMaximum < 0e0 || optInMaximum > 1.7976931348623157e308 )
      return TA_BAD_PARAM;
   if( !outReal )
      return TA_BAD_PARAM;

   if( startIdx < 1 )
   {
      startIdx = 1;
   }
   if( startIdx > endIdx )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return TA_SUCCESS;
   }
   af = optInAcceleration;
   if( af > optInMaximum )
   {
      optInAcceleration = optInMaximum;
      af = optInAcceleration;
   }
   retCode = TA_S_MINUS_DM_Unguarded(startIdx,startIdx,inHigh,inLow,1,&tempInt,&tempInt,ep_temp);
   if( ep_temp[0] > 0 )
   {
      isLong = 0;
   } else 
   {
      isLong = 1;
   }
   if( retCode != TA_SUCCESS )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return retCode;
   }
   *outBegIdx= startIdx;
   outIdx = 0;
   todayIdx = startIdx;
   newHigh = inHigh[todayIdx - 1];
   newLow = inLow[todayIdx - 1];
   if( isLong == 1 )
   {
      ep = inHigh[todayIdx];
      sar = newLow;
   } else 
   {
      ep = inLow[todayIdx];
      sar = newHigh;
   }
   newLow = inLow[todayIdx];
   newHigh = inHigh[todayIdx];
   while( todayIdx <= endIdx )
   {
      prevLow = newLow;
      prevHigh = newHigh;
      newLow = inLow[todayIdx];
      newHigh = inHigh[todayIdx];
      todayIdx += 1;
      if( isLong == 1 )
      {
         if( newLow <= sar )
         {
            isLong = 0;
            sar = ep;
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
            outReal[outIdx++] = sar;
            af = optInAcceleration;
            ep = newLow;
            sar = sar + af * (ep - sar);
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
         } else 
         {
            outReal[outIdx++] = sar;
            if( newHigh > ep )
            {
               ep = newHigh;
               af += optInAcceleration;
               if( af > optInMaximum )
               {
                  af = optInMaximum;
               }
            }
            sar = sar + af * (ep - sar);
            if( sar > prevLow )
            {
               sar = prevLow;
            }
            if( sar > newLow )
            {
               sar = newLow;
            }
         }
      } else if( newHigh >= sar )
      {
         isLong = 1;
         sar = ep;
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
         outReal[outIdx++] = sar;
         af = optInAcceleration;
         ep = newHigh;
         sar = sar + af * (ep - sar);
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
      } else 
      {
         outReal[outIdx++] = sar;
         if( newLow < ep )
         {
            ep = newLow;
            af += optInAcceleration;
            if( af > optInMaximum )
            {
               af = optInMaximum;
            }
         }
         sar = sar + af * (ep - sar);
         if( sar < prevHigh )
         {
            sar = prevHigh;
         }
         if( sar < newHigh )
         {
            sar = newHigh;
         }
      }
   }
   *outNBElement= outIdx;
   return TA_SUCCESS;
}

TA_RetCode TA_S_SAR_Unguarded( int    startIdx,
                               int    endIdx,
                               const float inHigh[],
                               const float inLow[],
                               double optInAcceleration,
                               double optInMaximum,
                               int          *outBegIdx,
                               int          *outNBElement,
                               double        outReal[] )
{
   TA_RetCode retCode;
   int isLong;
   int todayIdx;
   int outIdx;
   int tempInt;
   double newHigh;
   double newLow;
   double prevHigh;
   double prevLow;
   double af;
   double ep;
   double sar;
   double ep_temp[1];

   if( startIdx < 1 )
   {
      startIdx = 1;
   }
   if( startIdx > endIdx )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return TA_SUCCESS;
   }
   af = optInAcceleration;
   if( af > optInMaximum )
   {
      optInAcceleration = optInMaximum;
      af = optInAcceleration;
   }
   retCode = TA_S_MINUS_DM_Unguarded(startIdx,startIdx,inHigh,inLow,1,&tempInt,&tempInt,ep_temp);
   if( ep_temp[0] > 0 )
   {
      isLong = 0;
   } else 
   {
      isLong = 1;
   }
   if( retCode != TA_SUCCESS )
   {
      *outBegIdx= 0;
      *outNBElement= 0;
      return retCode;
   }
   *outBegIdx= startIdx;
   outIdx = 0;
   todayIdx = startIdx;
   newHigh = inHigh[todayIdx - 1];
   newLow = inLow[todayIdx - 1];
   if( isLong == 1 )
   {
      ep = inHigh[todayIdx];
      sar = newLow;
   } else 
   {
      ep = inLow[todayIdx];
      sar = newHigh;
   }
   newLow = inLow[todayIdx];
   newHigh = inHigh[todayIdx];
   while( todayIdx <= endIdx )
   {
      prevLow = newLow;
      prevHigh = newHigh;
      newLow = inLow[todayIdx];
      newHigh = inHigh[todayIdx];
      todayIdx += 1;
      if( isLong == 1 )
      {
         if( newLow <= sar )
         {
            isLong = 0;
            sar = ep;
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
            outReal[outIdx++] = sar;
            af = optInAcceleration;
            ep = newLow;
            sar = sar + af * (ep - sar);
            if( sar < prevHigh )
            {
               sar = prevHigh;
            }
            if( sar < newHigh )
            {
               sar = newHigh;
            }
         } else 
         {
            outReal[outIdx++] = sar;
            if( newHigh > ep )
            {
               ep = newHigh;
               af += optInAcceleration;
               if( af > optInMaximum )
               {
                  af = optInMaximum;
               }
            }
            sar = sar + af * (ep - sar);
            if( sar > prevLow )
            {
               sar = prevLow;
            }
            if( sar > newLow )
            {
               sar = newLow;
            }
         }
      } else if( newHigh >= sar )
      {
         isLong = 1;
         sar = ep;
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
         outReal[outIdx++] = sar;
         af = optInAcceleration;
         ep = newHigh;
         sar = sar + af * (ep - sar);
         if( sar > prevLow )
         {
            sar = prevLow;
         }
         if( sar > newLow )
         {
            sar = newLow;
         }
      } else 
      {
         outReal[outIdx++] = sar;
         if( newLow < ep )
         {
            ep = newLow;
            af += optInAcceleration;
            if( af > optInMaximum )
            {
               af = optInMaximum;
            }
         }
         sar = sar + af * (ep - sar);
         if( sar < prevHigh )
         {
            sar = prevHigh;
         }
         if( sar < newHigh )
         {
            sar = newHigh;
         }
      }
   }
   *outNBElement= outIdx;
   return TA_SUCCESS;
}

