/* nag_mesh2d_bound (d06bac) Example Program.
 *
 * NAGPRODCODE Version.
 *
 * Copyright 2016 Numerical Algorithms Group.
 *
 * Mark 26, 2016.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagd06.h>

/* Structure to allow data to be passed into */
/* the user-supplied function fbnd */

struct user
{
  /* details of the ellipse containing the NAG logo */

  double xa, xb, x0, y0;
};

#ifdef __cplusplus
extern "C"
{
#endif
  static double NAG_CALL fbnd(Integer, double, double, Nag_Comm *);
#ifdef __cplusplus
}
#endif

#define EDGE(I, J)   edge[3*((J) -1)+(I) -1]
#define LINED(I, J)  lined[4*((J) -1)+(I) -1]
#define CONN(I, J)   conn[3*((J) -1)+(I) -1]
#define COOR(I, J)   coor[2*((J) -1)+(I) -1]
#define COORCH(I, J) coorch[2*((J) -1)+(I) -1]
#define CRUS(I, J)   crus[2*((J) -1)+(I) -1]

int main(void)
{
  const Integer sdcrus = 4, nvmax = 1000, nedmx = 300, nvint = 0;
  struct user ellipse;
  Nag_Comm comm;
  double x0, xa, xb, xmax, xmin, y0, ymax, ymin;
  Integer exit_status, i, itrace, j, k, ncomp, nedge, nelt, nlines;
  Integer npropa, nv, nvb, reftk, l;
  char pmesh[2];
  double *coor = 0, *coorch = 0, *crus = 0, *rate = 0, *weight = 0;
  Integer *conn = 0, *edge = 0, *lcomp = 0, *lined = 0, *nlcomp = 0;
  NagError fail;

  INIT_FAIL(fail);

  exit_status = 0;

  printf(" nag_mesh2d_bound (d06bac) Example Program Results\n\n");
  fflush(stdout);

  /* Skip heading in data file */
  scanf("%*[^\n] ");

  /* Initialize boundary mesh inputs: */
  /* the number of line and of the characteristic points of */
  /* the boundary mesh */
  scanf("%" NAG_IFMT "%*[^\n] ", &nlines);

  /* Allocate memory */

  if (!(coor = NAG_ALLOC(2 * nvmax, double)) ||
      !(coorch = NAG_ALLOC(2 * nlines, double)) ||
      !(crus = NAG_ALLOC(2 * sdcrus, double)) ||
      !(rate = NAG_ALLOC(nlines, double)) ||
      !(weight = NAG_ALLOC(1, double)) ||
      !(conn = NAG_ALLOC(3 * (2 * nvmax + 5), Integer)) ||
      !(edge = NAG_ALLOC(3 * nedmx, Integer)) ||
      !(lined = NAG_ALLOC(4 * nlines, Integer)) ||
      !(lcomp = NAG_ALLOC(nlines, Integer)))
  {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }

  /* The ellipse boundary which envelops  */
  /* the NAG Logo, the N, the A and the G */
  for (j = 1; j <= nlines; ++j)
    scanf("%lf", &COORCH(1, j));
  scanf("%*[^\n] ");
  for (j = 1; j <= nlines; ++j)
    scanf("%lf", &COORCH(2, j));
  scanf("%*[^\n] ");
  for (j = 1; j <= sdcrus; ++j)
    scanf("%lf", &CRUS(1, j));
  scanf("%*[^\n] ");
  for (j = 1; j <= sdcrus; ++j)
    scanf("%lf", &CRUS(2, j));
  scanf("%*[^\n] ");

  /* The lines of the boundary mesh */

  for (j = 1; j <= nlines; ++j) {
    for (i = 1; i <= 4; ++i)
      scanf("%" NAG_IFMT "", &LINED(i, j));
    scanf("%lf", &rate[j - 1]);
  }
  scanf("%*[^\n] ");

  /* The number of connected components  */
  /* to the boundary and their information */
  scanf("%" NAG_IFMT "%*[^\n] ", &ncomp);

  /* Allocate memory */

  if (!(nlcomp = NAG_ALLOC(ncomp, Integer)))
  {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }

  j = 0;
  for (i = 0; i < ncomp; ++i) {
    scanf("%" NAG_IFMT "", &nlcomp[i]);
    scanf("%*[^\n] ");
    l = j + abs(nlcomp[i]);
    for (k = j; k < l; ++k)
      scanf("%" NAG_IFMT "", &lcomp[k]);
    scanf("%*[^\n] ");

    j += abs(nlcomp[i]);
  }
  scanf(" ' %1s '%*[^\n] ", pmesh);

  /* Data passed to the user-supplied function */

  xmin = COORCH(1, 4);
  xmax = COORCH(1, 2);
  ymin = COORCH(2, 1);
  ymax = COORCH(2, 3);

  xa = (xmax - xmin) / 2.0;
  xb = (ymax - ymin) / 2.0;

  x0 = (xmin + xmax) / 2.0;
  y0 = (ymin + ymax) / 2.0;

  comm.p = (Pointer) &ellipse;

  ellipse.xa = xa;
  ellipse.xb = xb;
  ellipse.x0 = x0;
  ellipse.y0 = y0;

  itrace = -1;

  /* Call to the boundary mesh generator */

  /* nag_mesh2d_bound (d06bac).
   * Generates a boundary mesh
   */
  nag_mesh2d_bound(nlines, coorch, lined, fbnd, crus, sdcrus, rate, ncomp,
                   nlcomp, lcomp, nvmax, nedmx, &nvb, coor, &nedge, edge,
                   itrace, 0, &comm, &fail);
  if (fail.code == NE_NOERROR) {
    if (pmesh[0] == 'N') {
      printf(" Boundary mesh characteristics\n");
      printf(" nvb   =%6" NAG_IFMT "\n", nvb);
      printf(" nedge =%6" NAG_IFMT "\n", nedge);
    }
    else if (pmesh[0] == 'Y') {
      /* Output the mesh to view it using the NAG Graphics Library */

      printf(" %10" NAG_IFMT "%10" NAG_IFMT "\n", nvb, nedge);

      for (i = 1; i <= nvb; ++i)
        printf("  %4" NAG_IFMT "  %15.6e  %15.6e  \n",
               i, COOR(1, i), COOR(2, i));

      for (i = 1; i <= nedge; ++i)
        printf(" %4" NAG_IFMT "%4" NAG_IFMT "%4" NAG_IFMT "%4" NAG_IFMT "\n",
               i, EDGE(1, i), EDGE(2, i), EDGE(3, i));
    }
    else {
      printf("Problem with the printing option Y or N\n");
      exit_status = -1;
      goto END;
    }
  }
  else {
    printf("Error from nag_mesh2d_bound (d06bac).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

  /* Initialize mesh control parameters */

  itrace = 0;
  npropa = 1;

  /* Call to the 2D Delaunay-Voronoi mesh generator */

  /* nag_mesh2d_delaunay (d06abc).
   * Generates a two-dimensional mesh using a Delaunay-Voronoi
   * process
   */
  nag_mesh2d_delaunay(nvb, nvint, nvmax, nedge, edge, &nv, &nelt, coor, conn,
                      weight, npropa, itrace, 0, &fail);
  if (fail.code == NE_NOERROR) {
    if (pmesh[0] == 'N') {
      printf(" Complete mesh characteristics (Delaunay-Voronoi)\n");
      printf("   nv (rounded to nearest 10) =%6" NAG_IFMT "\n",
             10*((nv+5)/10));
      printf(" nelt (rounded to nearest 10) =%6" NAG_IFMT "\n",
             10*((nelt+5)/10));
    }
    else if (pmesh[0] == 'Y') {
      /* Output the mesh to view it using the NAG Graphics Library */

      printf(" %10" NAG_IFMT "%10" NAG_IFMT "\n", nv, nelt);

      for (i = 1; i <= nv; ++i)
        printf("  %15.6e  %15.6e  \n", COOR(1, i), COOR(2, i));

      reftk = 0;
      for (k = 1; k <= nelt; ++k)
        printf(" %10" NAG_IFMT "%10" NAG_IFMT "%10" NAG_IFMT "%10" NAG_IFMT
               "\n", CONN(1, k), CONN(2, k), CONN(3, k), reftk);
    }
    else {
      printf("Problem with the printing option Y or N\n");
      exit_status = -1;
      goto END;
    }
  }
  else {
    printf("Error from nag_mesh2d_delaunay (d06abc).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

  /* Call to the 2D Advancing front mesh generator */

  /* nag_mesh2d_front (d06acc).
   * Generates a two-dimensional mesh using an Advancing-front
   * method
   */
  nag_mesh2d_front(nvb, nvint, nvmax, nedge, edge, &nv, &nelt, coor,
                   conn, weight, itrace, 0, &fail);
  if (fail.code == NE_NOERROR) {
    if (pmesh[0] == 'N') {
      printf(" Complete mesh characteristics (Advancing Front)\n");
      printf("   nv (rounded to nearest 10) =%6" NAG_IFMT "\n",
             10*((nv+5)/10));
      printf(" nelt (rounded to nearest 10) =%6" NAG_IFMT "\n",
             10*((nelt+5)/10));
    }
    else if (pmesh[0] == 'Y') {
      /* Output the mesh to view it using the NAG Graphics Library */

      printf(" %10" NAG_IFMT "%10" NAG_IFMT "\n", nv, nelt);

      for (i = 1; i <= nv; ++i)
        printf("  %15.6e  %15.6e  \n", COOR(1, i), COOR(2, i));

      reftk = 0;
      for (k = 1; k <= nelt; ++k)
        printf(" %10" NAG_IFMT "%10" NAG_IFMT "%10" NAG_IFMT "%10" NAG_IFMT
               "\n", CONN(1, k), CONN(2, k), CONN(3, k), reftk);
    }
    else {
      printf("Problem with the printing option Y or N\n");
      exit_status = -1;
      goto END;
    }
  }
  else {
    printf("Error from nag_mesh2d_front (d06acc).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

END:
  NAG_FREE(coor);
  NAG_FREE(coorch);
  NAG_FREE(crus);
  NAG_FREE(rate);
  NAG_FREE(weight);
  NAG_FREE(conn);
  NAG_FREE(edge);
  NAG_FREE(lcomp);
  NAG_FREE(lined);
  NAG_FREE(nlcomp);

  return exit_status;
}

static double NAG_CALL fbnd(Integer i, double x, double y, Nag_Comm *pcomm)
{
  double ret_val, d1, d2;
  double radius2, x0, xa, xb, y0;
  struct user *ellipse = (struct user *) pcomm->p;

  xa = ellipse->xa;
  xb = ellipse->xb;
  x0 = ellipse->x0;
  y0 = ellipse->y0;

  ret_val = 0.0;

  switch (i) {
  case 1:

    /* line 1,2,3, and 4: ellipse centred in (X0,Y0) with */
    /* XA and XB as coefficients */

    d1 = (x - x0) / xa;
    d2 = (y - y0) / xb;

    ret_val = d1 * d1 + d2 * d2 - 1.0;
    break;

  case 2:

    /* line 24, 27, 33 and 38 are a circle centred in (X0,Y0) */
    /* with radius SQRT(RADIUS2) */

    x0 = 20.5;
    y0 = 4.0;
    radius2 = 4.25;

    d1 = x - x0;
    d2 = y - y0;

    ret_val = d1 * d1 + d2 * d2 - radius2;
    break;

  case 3:

    x0 = 17.0;
    y0 = 8.5;
    radius2 = 5.0;

    d1 = x - x0;
    d2 = y - y0;

    ret_val = d1 * d1 + d2 * d2 - radius2;
    break;

  case 4:

    x0 = 17.0;
    y0 = 8.5;
    radius2 = 5.0;

    d1 = x - x0;
    d2 = y - y0;

    ret_val = d1 * d1 + d2 * d2 - radius2;
    break;

  case 5:

    x0 = 19.5;
    y0 = 4.0;
    radius2 = 1.25;

    d1 = x - x0;
    d2 = y - y0;

    ret_val = d1 * d1 + d2 * d2 - radius2;
    break;

  default:
    break;
  }

  return ret_val;
}