/* See epswr_figure.h */
/* Last edited on 2020-10-27 16:59:17 by jstolfi */

#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <limits.h>
#include <assert.h>

#include <bool.h>
#include <affirm.h>

#include <epswr_def.h>

#include <epswr_figure.h>

void epswr_check_param(const char *name, double z, double zMin, double zMax)
  { if ((z < zMin) || (z > zMax))
      { fprintf(stderr, "** error: %s = %8.3f not in [%8.3f __ %8.3f]\n", name, z, zMin, zMax);
        assert(FALSE);
      }
  }

double epswr_round_to_nice(double x)
  { /* Special cases for 0 and infinity: */
    if ((x == 0) || (x == INF)) { return x; }
    /* Remove the sign of {x} and save it in {s}: */
    double s = (x < 0 ? -1 : +1);
    x = fabs(x);
    /* Compensate for rounding errors in the algorithm below: */
    x = 0.9999999 * x;
    /* If {x} is too small, don't bother: */
    if (x < 1.0e-300) { return s*1.0e-300; }
    /* Finds the smallest power {z} of 10 such that {z > x}: */
    double z = 1.0;
    while (z/10.0 > x) { z /= 10.0; }
    while (z <= x ) { z *= 10.0; }
    /* Check for overflow: */
    if (z == INF) { return s * INF; }
    /* Finds a nice multiple of that power of 10: */
    if (x < 0.20 * z)
      { return 0.20 * s * z; }
    else if (x < 0.25 * z)
      { return 0.25 * s * z; }
    else if (x < 0.5 * z)
      { return 0.5 * s * z; }
    else
      { return s * z; }
  }

double epswr_round_dim_mm(double x_mm, double dpi)
  {
    if (dpi == 0.0)
      { return x_mm; }
    else if (x_mm == 0.0)
      { return 0.0; }
    else
      { double dp_per_mm = (dpi/25.4)/2.0;   /* Dot pairs per  mm. */
        double x_dp_raw = x_mm * dp_per_mm;  /* Dimension in dot pairs, unrounded. */
        double x_dp = floor(x_dp_raw + 0.5); /* Dimension in dot pairs, rounded; */
        if (fabs(x_dp) == 0) { x_dp = (x_mm < 0 ? -1.0 : 1.0); };  /* Ensure min size. */
        return x_dp/dp_per_mm;
      }
  }