/**
* Copyright 2005-2007 ECMWF
*
* Licensed under the GNU Lesser General Public License which
* incorporates the terms and conditions of version 3 of the GNU
* General Public License.
* See LICENSE and gpl-3.0.txt for details.
*/

/************************************
 *   Enrico Fucile
 ************************************/

#include "grib_api_internal.h"
/*
   This is used by make_class.pl

   START_CLASS_DEF
   CLASS      = accessor
   SUPER      = grib_accessor_class_gen
   IMPLEMENTS = pack_long;
   IMPLEMENTS = init;get_native_type
   MEMBERS = const char* values
   MEMBERS = const char* Ni
   MEMBERS = const char* Nj
   MEMBERS = const char* i_scans_negatively
   MEMBERS = const char* j_scans_positively
   MEMBERS = const char* first
   MEMBERS = const char* last
   MEMBERS = const char* axis
   END_CLASS_DEF

 */

/* START_CLASS_IMP */

/*

Don't edit anything between START_CLASS_IMP and END_CLASS_IMP
Instead edit values between START_CLASS_DEF and END_CLASS_DEF
or edit "accessor.class" and rerun ./make_class.pl

*/

static int  get_native_type(grib_accessor*);
static int pack_long(grib_accessor*, const long* val,size_t *len);
static void init(grib_accessor*,const long, grib_arguments* );
static void init_class(grib_accessor_class*);

typedef struct grib_accessor_change_scanning_direction {
    grib_accessor          att;
/* Members defined in gen */
/* Members defined in change_scanning_direction */
	const char* values;
	const char* Ni;
	const char* Nj;
	const char* i_scans_negatively;
	const char* j_scans_positively;
	const char* first;
	const char* last;
	const char* axis;
} grib_accessor_change_scanning_direction;

extern grib_accessor_class* grib_accessor_class_gen;

static grib_accessor_class _grib_accessor_class_change_scanning_direction = {
    &grib_accessor_class_gen,                      /* super                     */
    "change_scanning_direction",                      /* name                      */
    sizeof(grib_accessor_change_scanning_direction),  /* size                      */
    0,                           /* inited */
    &init_class,                 /* init_class */
    &init,                       /* init                      */
    0,                  /* post_init                      */
    0,                    /* free mem                       */
    0,                       /* describes himself         */
    0,                /* get length of section     */
    0,                /* get number of values      */
    0,                 /* get number of bytes      */
    0,                /* get offset to bytes           */
    &get_native_type,            /* get native type               */
    0,                /* get sub_section                */
    0,               /* grib_pack procedures long      */
    0,               /* grib_pack procedures long      */
    &pack_long,                  /* grib_pack procedures long      */
    0,                /* grib_unpack procedures long    */
    0,                /* grib_pack procedures double    */
    0,              /* grib_unpack procedures double  */
    0,                /* grib_pack procedures string    */
    0,              /* grib_unpack procedures string  */
    0,                 /* grib_pack procedures bytes     */
    0,               /* grib_unpack procedures bytes   */
    0,            /* pack_expression */
    0,              /* notify_change   */
    0,                /* update_size   */
    0,            /* preferred_size   */
    0,                    /* resize   */
    0,      /* nearest_smaller_value */
    0,                       /* next accessor    */
    0,                    /* compare vs. another accessor   */
    0,     /* unpack only ith value          */
    0,     /* unpack a subarray         */
    0,             		/* clear          */
};


grib_accessor_class* grib_accessor_class_change_scanning_direction = &_grib_accessor_class_change_scanning_direction;


static void init_class(grib_accessor_class* c)
{
	c->dump	=	(*(c->super))->dump;
	c->next_offset	=	(*(c->super))->next_offset;
	c->value_count	=	(*(c->super))->value_count;
	c->byte_count	=	(*(c->super))->byte_count;
	c->byte_offset	=	(*(c->super))->byte_offset;
	c->sub_section	=	(*(c->super))->sub_section;
	c->pack_missing	=	(*(c->super))->pack_missing;
	c->is_missing	=	(*(c->super))->is_missing;
	c->unpack_long	=	(*(c->super))->unpack_long;
	c->pack_double	=	(*(c->super))->pack_double;
	c->unpack_double	=	(*(c->super))->unpack_double;
	c->pack_string	=	(*(c->super))->pack_string;
	c->unpack_string	=	(*(c->super))->unpack_string;
	c->pack_bytes	=	(*(c->super))->pack_bytes;
	c->unpack_bytes	=	(*(c->super))->unpack_bytes;
	c->pack_expression	=	(*(c->super))->pack_expression;
	c->notify_change	=	(*(c->super))->notify_change;
	c->update_size	=	(*(c->super))->update_size;
	c->preferred_size	=	(*(c->super))->preferred_size;
	c->resize	=	(*(c->super))->resize;
	c->nearest_smaller_value	=	(*(c->super))->nearest_smaller_value;
	c->next	=	(*(c->super))->next;
	c->compare	=	(*(c->super))->compare;
	c->unpack_double_element	=	(*(c->super))->unpack_double_element;
	c->unpack_double_subarray	=	(*(c->super))->unpack_double_subarray;
	c->clear	=	(*(c->super))->clear;
}

/* END_CLASS_IMP */

static void init(grib_accessor* a, const long len , grib_arguments* args )
{
  int n=0;
  grib_accessor_change_scanning_direction* self= (grib_accessor_change_scanning_direction*)a;

  self->values=grib_arguments_get_name(a->parent->h,args,n++);
  self->Ni=grib_arguments_get_name(a->parent->h,args,n++);
  self->Nj=grib_arguments_get_name(a->parent->h,args,n++);
  self->i_scans_negatively=grib_arguments_get_name(a->parent->h,args,n++);
  self->j_scans_positively=grib_arguments_get_name(a->parent->h,args,n++);
  self->first=grib_arguments_get_name(a->parent->h,args,n++);
  self->last=grib_arguments_get_name(a->parent->h,args,n++);
  self->axis=grib_arguments_get_name(a->parent->h,args,n++);
  
  a->flags |= GRIB_ACCESSOR_FLAG_FUNCTION;
  a->length = 0;
}

static int pack_long(grib_accessor* a, const long* val, size_t *len)
{
  int ret=0;
  long i,j,jr,end,Ni,Nj,k,kp;
  double tmp;
  long iScansNegatively=0;
  long jScansPositively=0;
  long first=0;
  long last=0;
  size_t size=0;
  double* values=NULL;
  grib_accessor_change_scanning_direction* self= (grib_accessor_change_scanning_direction*)a;
  grib_context* c=a->parent->h->context;
  grib_handle* h=a->parent->h;

  if (*val==0) return 0;

  if((ret = grib_get_long_internal(h,self->Ni,&Ni))
      != GRIB_SUCCESS) return ret;

  if((ret = grib_get_long_internal(h,self->Nj,&Nj))
      != GRIB_SUCCESS) return ret;
  
  if((ret = grib_get_long_internal(h,self->i_scans_negatively,&iScansNegatively))
      != GRIB_SUCCESS) return ret;

  if((ret = grib_get_long_internal(h,self->j_scans_positively,&jScansPositively))
      != GRIB_SUCCESS) return ret;

  if((ret = grib_get_long_internal(h,self->first,&first))
      != GRIB_SUCCESS) return ret;
  if((ret = grib_get_long_internal(h,self->last,&last))
      != GRIB_SUCCESS) return ret;

  if ( (ret=grib_get_size(h,self->values,&size)) != GRIB_SUCCESS)  return ret;

  if (size>Ni*Nj) {
    grib_context_log(c,GRIB_LOG_ERROR,"change_scanning_direction: wrong values size!=Ni*Nj (%ld!=%ld*%ld)",size,Ni,Nj);
    return GRIB_WRONG_ARRAY_SIZE;
  }

  values=(double*)grib_context_malloc(c,size*sizeof(double));
  if (!values) return GRIB_OUT_OF_MEMORY;

  if((ret = grib_get_double_array_internal(h,self->values,values,&size))
       != GRIB_SUCCESS) {
        grib_context_free(c,values);
        return ret;
  }

  if (self->axis[0] == 'x') {
    end=(Ni+0.5)/2;
    for (j=0;j<Nj;j++) {
      jr=Ni*j;
      for (i=0;i<end;i++) {
        k=jr+i;
        kp=jr+Ni-i-1;
        tmp=values[k];
        values[k]=values[kp];
        values[kp]=tmp;
      }
    }
    iScansNegatively=!iScansNegatively;
    if((ret = grib_set_long_internal(h,self->i_scans_negatively,iScansNegatively))
        != GRIB_SUCCESS) return ret;
  } else {
    long kpj;
    end=(Nj+0.5)/2;
    for (i=0;i<Ni;i++) {
      kpj=Ni*(Nj-1);
      for (j=0;j<end;j++) {
        k=Ni*j+i;
        kp=kpj-Ni*j+i;
        tmp=values[k];
        values[k]=values[kp];
        values[kp]=tmp;
      }
    }
    jScansPositively=!jScansPositively;
    if((ret = grib_set_long_internal(h,self->j_scans_positively,jScansPositively))
        != GRIB_SUCCESS) return ret;
  }

  if((ret = grib_set_double_array_internal(h,self->values,values,size))
      != GRIB_SUCCESS) {
    grib_context_free(c,values);
    return ret;
  }

  if((ret = grib_set_long_internal(h,self->first,last))
      != GRIB_SUCCESS) return ret;

  if((ret = grib_set_long_internal(h,self->last,first))
      != GRIB_SUCCESS) return ret;

  grib_context_free(c,values);

  return GRIB_SUCCESS;
}

static int  get_native_type(grib_accessor* a){
    return GRIB_TYPE_LONG;
}


