package org.catacomb.numeric.function;
   
   import org.catacomb.report.E;
   
   
   public class HoldLastScalarFunction implements ScalarFunction {
   
       int ntv;
       double[] times;
      double[] values;
  
      int itv;
  
  
      public HoldLastScalarFunction(double t, double v) {
          times = new double[4];
          values = new double[4];
          times[0] = t;
          values[0] = v;
          ntv = 1;
      }
  
  
      public void addTransition(double t, double v) {
          if (t < times[ntv-1]) {
              E.missing("cant add prior transition");
          } else {
              if (ntv == times.length) {
                  double[] tt = new double[2 * times.length];
                  double[] vv = new double[2 * values.length];
                  for (int i = 0; i < ntv; i++) {
                      tt[i] = times[i];
                      vv[i] = values[i];
                  }
                  times = tt;
                  values = vv;
              }
  
              times[ntv] = t;
              values[ntv] =v;
              ntv += 1;
          }
      }
  
  
      public void fixate() {
          addTransition(1.e99, values[ntv-1]);
          // could trim arrays here - EFF
          itv = 0;
  
          /*
          E.info("fixated hlsf");
          for (int i = 0; i < ntv; i++) {
             E.info("tv point " + times[i] + " " + values[i]);
          }
          */
      }
  
  
  
      public double getScalar(double t) {
          if (t >= times[itv] && t < times[itv+1]) {
              // no change;
  
          } else if (t < times[itv]) {
              itv = 0;
              while (itv < ntv-1 && t >= times[itv+1]) {
                  itv++;
              }
  
          } else {
              while (itv < ntv-1 && t >= times[itv+1]) {
                  itv++;
                  //  E.info("HLSF advanced " + itv + " " + values[itv]);
              }
          }
  
          return values[itv];
      }
  
  
  
  
  
  }