#include "rb_lapack.h"

extern VOID zppcon_(char* uplo, integer* n, doublecomplex* ap, doublereal* anorm, doublereal* rcond, doublecomplex* work, doublereal* rwork, integer* info);


static VALUE
rblapack_zppcon(int argc, VALUE *argv, VALUE self){
  VALUE rblapack_uplo;
  char uplo; 
  VALUE rblapack_ap;
  doublecomplex *ap; 
  VALUE rblapack_anorm;
  doublereal anorm; 
  VALUE rblapack_rcond;
  doublereal rcond; 
  VALUE rblapack_info;
  integer info; 
  doublecomplex *work;
  doublereal *rwork;

  integer ldap;
  integer n;

  VALUE rblapack_options;
  if (argc > 0 && TYPE(argv[argc-1]) == T_HASH) {
    argc--;
    rblapack_options = argv[argc];
    if (rb_hash_aref(rblapack_options, sHelp) == Qtrue) {
      printf("%s\n", "USAGE:\n  rcond, info = NumRu::Lapack.zppcon( uplo, ap, anorm, [:usage => usage, :help => help])\n\n\nFORTRAN MANUAL\n      SUBROUTINE ZPPCON( UPLO, N, AP, ANORM, RCOND, WORK, RWORK, INFO )\n\n*  Purpose\n*  =======\n*\n*  ZPPCON estimates the reciprocal of the condition number (in the\n*  1-norm) of a complex Hermitian positive definite packed matrix using\n*  the Cholesky factorization A = U**H*U or A = L*L**H computed by\n*  ZPPTRF.\n*\n*  An estimate is obtained for norm(inv(A)), and the reciprocal of the\n*  condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).\n*\n\n*  Arguments\n*  =========\n*\n*  UPLO    (input) CHARACTER*1\n*          = 'U':  Upper triangle of A is stored;\n*          = 'L':  Lower triangle of A is stored.\n*\n*  N       (input) INTEGER\n*          The order of the matrix A.  N >= 0.\n*\n*  AP      (input) COMPLEX*16 array, dimension (N*(N+1)/2)\n*          The triangular factor U or L from the Cholesky factorization\n*          A = U**H*U or A = L*L**H, packed columnwise in a linear\n*          array.  The j-th column of U or L is stored in the array AP\n*          as follows:\n*          if UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j;\n*          if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.\n*\n*  ANORM   (input) DOUBLE PRECISION\n*          The 1-norm (or infinity-norm) of the Hermitian matrix A.\n*\n*  RCOND   (output) DOUBLE PRECISION\n*          The reciprocal of the condition number of the matrix A,\n*          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an\n*          estimate of the 1-norm of inv(A) computed in this routine.\n*\n*  WORK    (workspace) COMPLEX*16 array, dimension (2*N)\n*\n*  RWORK   (workspace) DOUBLE PRECISION array, dimension (N)\n*\n*  INFO    (output) INTEGER\n*          = 0:  successful exit\n*          < 0:  if INFO = -i, the i-th argument had an illegal value\n*\n\n*  =====================================================================\n*\n\n");
      return Qnil;
    }
    if (rb_hash_aref(rblapack_options, sUsage) == Qtrue) {
      printf("%s\n", "USAGE:\n  rcond, info = NumRu::Lapack.zppcon( uplo, ap, anorm, [:usage => usage, :help => help])\n");
      return Qnil;
    } 
  } else
    rblapack_options = Qnil;
  if (argc != 3 && argc != 3)
    rb_raise(rb_eArgError,"wrong number of arguments (%d for 3)", argc);
  rblapack_uplo = argv[0];
  rblapack_ap = argv[1];
  rblapack_anorm = argv[2];
  if (argc == 3) {
  } else if (rblapack_options != Qnil) {
  } else {
  }

  uplo = StringValueCStr(rblapack_uplo)[0];
  anorm = NUM2DBL(rblapack_anorm);
  if (!NA_IsNArray(rblapack_ap))
    rb_raise(rb_eArgError, "ap (2th argument) must be NArray");
  if (NA_RANK(rblapack_ap) != 1)
    rb_raise(rb_eArgError, "rank of ap (2th argument) must be %d", 1);
  ldap = NA_SHAPE0(rblapack_ap);
  if (NA_TYPE(rblapack_ap) != NA_DCOMPLEX)
    rblapack_ap = na_change_type(rblapack_ap, NA_DCOMPLEX);
  ap = NA_PTR_TYPE(rblapack_ap, doublecomplex*);
  n = ((int)sqrtf(ldap*8+1.0f)-1)/2;
  work = ALLOC_N(doublecomplex, (2*n));
  rwork = ALLOC_N(doublereal, (n));

  zppcon_(&uplo, &n, ap, &anorm, &rcond, work, rwork, &info);

  free(work);
  free(rwork);
  rblapack_rcond = rb_float_new((double)rcond);
  rblapack_info = INT2NUM(info);
  return rb_ary_new3(2, rblapack_rcond, rblapack_info);
}

void
init_lapack_zppcon(VALUE mLapack, VALUE sH, VALUE sU, VALUE zero){
  sHelp = sH;
  sUsage = sU;
  rblapack_ZERO = zero;

  rb_define_module_function(mLapack, "zppcon", rblapack_zppcon, -1);
}
