/* nag_mesh2d_bound (d06bac) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#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");

  /* Skip heading in data file */

  scanf("%*[^\n] ");

  /* Initialise boundary mesh inputs: */
  /* the number of line and of the characteristic points of */
  /* the boundary mesh */

  scanf("%ld%*[^\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("%ld", &LINED(i, j));
      scanf("%lf", &rate[j-1]);
    }
  scanf("%*[^\n] ");

  /* The number of connected components  */
  /* to the boundary and their information */

  scanf("%ld%*[^\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("%ld", &nlcomp[i]);
      scanf("%*[^\n] ");
      l = j + abs(nlcomp[i]);

      for (k = j; k < l; ++k) scanf("%ld", &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   =%6ld\n", nvb);
          printf(" nedge =%6ld\n", nedge);
        }
      else if (pmesh[0] == 'Y')
        {
          /* Output the mesh to view it using the NAG Graphics Library */

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

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

          for (i = 1; i <= nedge; ++i)
            printf(" %4ld%4ld%4ld%4ld\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;
    }

  /* Initialise 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   =%6ld\n", nv);
          printf(" nelt =%6ld\n", nelt);
        }
      else if (pmesh[0] == 'Y')
        {
          /* Output the mesh to view it using the NAG Graphics Library */

          printf(" %10ld%10ld\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(" %10ld%10ld%10ld%10ld\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   =%6ld\n", nv);
          printf(" nelt =%6ld\n", nelt);
        }
      else if (pmesh[0] == 'Y')
        {
          /* Output the mesh to view it using the NAG Graphics Library */

          printf(" %10ld%10ld\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(" %10ld%10ld%10ld%10ld\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:
  if (coor) NAG_FREE(coor);
  if (coorch) NAG_FREE(coorch);
  if (crus) NAG_FREE(crus);
  if (rate) NAG_FREE(rate);
  if (weight) NAG_FREE(weight);
  if (conn) NAG_FREE(conn);
  if (edge) NAG_FREE(edge);
  if (lcomp) NAG_FREE(lcomp);
  if (lined) NAG_FREE(lined);
  if (nlcomp) 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;
}