/*
 * Copyright 2005-2016 ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

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

   START_CLASS_DEF
   CLASS      = accessor
   SUPER      = grib_accessor_class_double
   IMPLEMENTS = unpack_double;pack_double;is_missing
   IMPLEMENTS = init
   MEMBERS=const char*                  directionIncrementGiven
   MEMBERS=const char*                  directionIncrement
   MEMBERS=const char*                  scansPositively
   MEMBERS=const char*                  first
   MEMBERS=const char*                  last
   MEMBERS=const char*                  numberOfPoints
   MEMBERS=const char*                  angleMultiplier
   MEMBERS=const char*                  angleDivisor
   MEMBERS=long                   isLongitude
   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 is_missing(grib_accessor*);
static int pack_double(grib_accessor*, const double* val,size_t *len);
static int unpack_double(grib_accessor*, double* val,size_t *len);
static void init(grib_accessor*,const long, grib_arguments* );
static void init_class(grib_accessor_class*);

typedef struct grib_accessor_latlon_increment {
    grib_accessor          att;
/* Members defined in gen */
/* Members defined in double */
/* Members defined in latlon_increment */
	const char*                  directionIncrementGiven;
	const char*                  directionIncrement;
	const char*                  scansPositively;
	const char*                  first;
	const char*                  last;
	const char*                  numberOfPoints;
	const char*                  angleMultiplier;
	const char*                  angleDivisor;
	long                   isLongitude;
} grib_accessor_latlon_increment;

extern grib_accessor_class* grib_accessor_class_double;

static grib_accessor_class _grib_accessor_class_latlon_increment = {
    &grib_accessor_class_double,                      /* super                     */
    "latlon_increment",                      /* name                      */
    sizeof(grib_accessor_latlon_increment),  /* 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 length of string      */
    0,                /* get number of values      */
    0,                 /* get number of bytes      */
    0,                /* get offset to bytes           */
    0,            /* get native type               */
    0,                /* get sub_section                */
    0,               /* grib_pack procedures long      */
    &is_missing,               /* grib_pack procedures long      */
    0,                  /* grib_pack procedures long      */
    0,                /* grib_unpack procedures long    */
    &pack_double,                /* grib_pack procedures double    */
    &unpack_double,              /* 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_latlon_increment = &_grib_accessor_class_latlon_increment;


static void init_class(grib_accessor_class* c)
{
	c->dump	=	(*(c->super))->dump;
	c->next_offset	=	(*(c->super))->next_offset;
	c->string_length	=	(*(c->super))->string_length;
	c->value_count	=	(*(c->super))->value_count;
	c->byte_count	=	(*(c->super))->byte_count;
	c->byte_offset	=	(*(c->super))->byte_offset;
	c->get_native_type	=	(*(c->super))->get_native_type;
	c->sub_section	=	(*(c->super))->sub_section;
	c->pack_missing	=	(*(c->super))->pack_missing;
	c->pack_long	=	(*(c->super))->pack_long;
	c->unpack_long	=	(*(c->super))->unpack_long;
	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 l, grib_arguments* c)
{
    grib_accessor_latlon_increment* self = (grib_accessor_latlon_increment*)a;
    int n = 0;

    self->directionIncrementGiven = grib_arguments_get_name(a->parent->h,c,n++);
    self->directionIncrement    = grib_arguments_get_name(a->parent->h,c,n++);
    self->scansPositively    = grib_arguments_get_name(a->parent->h,c,n++);
    self->first = grib_arguments_get_name(a->parent->h,c,n++);
    self->last    = grib_arguments_get_name(a->parent->h,c,n++);
    self->numberOfPoints    = grib_arguments_get_name(a->parent->h,c,n++);
    self->angleMultiplier    = grib_arguments_get_name(a->parent->h,c,n++);
    self->angleDivisor   = grib_arguments_get_name(a->parent->h,c,n++);
    self->isLongitude=grib_arguments_get_long(a->parent->h, c,n++);
}

static int unpack_double(grib_accessor* a, double* val, size_t *len)
{
    grib_accessor_latlon_increment* self = (grib_accessor_latlon_increment*)a;
    int ret = 0;

    long directionIncrementGiven=0;
    long directionIncrement=0;
    long angleDivisor=1;
    long angleMultiplier=1;
    double first = 0;
    double last = 0;
    long numberOfPoints = 0;
    long scansPositively = 0;

    if(*len < 1) return GRIB_ARRAY_TOO_SMALL;

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

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

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

    if((ret = grib_get_double_internal(a->parent->h, self->first,&first)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_double_internal(a->parent->h, self->last,&last)) != GRIB_SUCCESS)
        return ret;

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

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

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

    if (self->isLongitude) {
        if (last < first && scansPositively) last+=360;
        /*if (last > first && !scansPositively) first-=360;*/
    }

    if (!directionIncrementGiven && numberOfPoints != GRIB_MISSING_LONG)
    {
        if (numberOfPoints<2) {
            /* We cannot compute the increment if we don't have enough points! */
            grib_context_log(a->parent->h->context, GRIB_LOG_ERROR,
                    "Cannot compute lat/lon increments. Not enough points!");
            return GRIB_GEOCALCULUS_PROBLEM;
        }
        if (!scansPositively) { /* scans negatively */
            if (first > last){
                *val=(first-last)/(numberOfPoints-1);
            }
            else {
                *val=(first+360.0-last)/(numberOfPoints-1);
            }
        }
        else
        {
            /* scans positively */
            if (last > first){
                *val=(last-first)/(numberOfPoints-1);
            }
            else {
                *val=(last+360.0-first)/(numberOfPoints-1);
            }
        }
    }
    else if (numberOfPoints == GRIB_MISSING_LONG)
    {
        *val = GRIB_MISSING_DOUBLE;
    }
    else
    {
        Assert(angleDivisor!=0);
        *val = (double)directionIncrement/angleDivisor*angleMultiplier;
    }

#if 0
    printf("unpack -- %s=%ld %s=%ld %s=%f %s=%f %s=%ld %s=%f\n",
            self->directionIncrementGiven,directionIncrementGiven,
            self->directionIncrement,directionIncrement,
            self->last,last,
            self->first,first,
            self->numberOfPoints,numberOfPoints,
            a->name,*val);
#endif
    if (ret == GRIB_SUCCESS) *len = 1;

    return ret;
}

static int pack_double(grib_accessor* a, const double* val, size_t *len)
{
    grib_accessor_latlon_increment* self = (grib_accessor_latlon_increment*)a;
    int ret = 0;
    long codedNumberOfPoints=0;

    long directionIncrementGiven=0;
    long directionIncrement=0;
    long angleDivisor=1;
    long angleMultiplier=1;
    double first = 0;
    double last = 0;
    long numberOfPoints = 0;
    /* long numberOfPointsInternal = 0; */
    long scansPositively = 0;
    double directionIncrementDouble=0;

    ret = grib_get_double_internal(a->parent->h, self->first,&first);
    if(ret != GRIB_SUCCESS) return ret;

    ret = grib_get_double_internal(a->parent->h, self->last,&last);
    if(ret != GRIB_SUCCESS) return ret;

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

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

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

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

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

    if (self->isLongitude) {
        if (last < first && scansPositively) last+=360;
        if (last > first && !scansPositively) first-=360;
    }

    if (*val == GRIB_MISSING_DOUBLE) {
        directionIncrement=GRIB_MISSING_LONG;
        directionIncrementGiven=1;
        numberOfPoints=GRIB_MISSING_LONG;
    } else {
        /* numberOfPointsInternal = 1+rint(fabs((last-first) / *val)); */

        directionIncrementDouble = rint (*val * (double)angleDivisor / (double)angleMultiplier);

        directionIncrement=(long)directionIncrementDouble;
        if (directionIncrement == 0 ) {
            directionIncrement=GRIB_MISSING_LONG;
            directionIncrementGiven=0;
        }
    }

    /*ret = grib_set_long_internal(a->parent->h, self->numberOfPoints,numberOfPoints);
     if(ret )
     grib_context_log(a->parent->h->context, GRIB_LOG_ERROR, "Accessor %s cannot pack value for %s error %d \n", a->name, self->numberOfPoints, ret);
    */

    grib_get_long_internal(a->parent->h, self->numberOfPoints,&codedNumberOfPoints);

    ret = grib_set_long_internal(a->parent->h, self->directionIncrement,directionIncrement);
    if(ret ) return ret;

    ret = grib_set_long_internal(a->parent->h, self->directionIncrementGiven,directionIncrementGiven);
    if(ret )return ret;

#if 0
    printf("pack -- %s=%ld %s=%ld \n ------- %s=%f %s=%f \n ------- %s=%ld codedNumberOfPoints=%ld %s=%f\n",
            self->directionIncrementGiven,directionIncrementGiven,
            self->directionIncrement,directionIncrement,
            self->last,last,
            self->first,first,
            self->numberOfPoints,numberOfPoints,
            codedNumberOfPoints,
            a->name,*val);
#endif
    if (ret == GRIB_SUCCESS) *len = 1;

    return ret;
}

static int is_missing(grib_accessor* a){

    size_t len=1;
    double val=0;

    unpack_double(a, &val, &len);

    return (val == GRIB_MISSING_DOUBLE);
}
