/*
 * Copyright 2005-2017 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.
 */


/*******************************************************
 *   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 = unpack_double;pack_double
   IMPLEMENTS = unpack_string;pack_string;string_length
   IMPLEMENTS = unpack_long;pack_long;destroy
   IMPLEMENTS = init;dump;value_count;get_native_type
   IMPLEMENTS = compare
    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_double(grib_accessor*, const double* val,size_t *len);
static int pack_long(grib_accessor*, const long* val,size_t *len);
static int pack_string(grib_accessor*, const char*, size_t *len);
static int unpack_double(grib_accessor*, double* val,size_t *len);
static int unpack_long(grib_accessor*, long* val,size_t *len);
static int unpack_string (grib_accessor*, char*, size_t *len);
static size_t string_length(grib_accessor*);
static int value_count(grib_accessor*,long*);
static void destroy(grib_context*,grib_accessor*);
static void dump(grib_accessor*, grib_dumper*);
static void init(grib_accessor*,const long, grib_arguments* );
static void init_class(grib_accessor_class*);
static int compare(grib_accessor*, grib_accessor*);

typedef struct grib_accessor_concept {
    grib_accessor          att;
/* Members defined in gen */
/* Members defined in concept */
} grib_accessor_concept;

extern grib_accessor_class* grib_accessor_class_gen;

static grib_accessor_class _grib_accessor_class_concept = {
    &grib_accessor_class_gen,                      /* super                     */
    "concept",                      /* name                      */
    sizeof(grib_accessor_concept),  /* size                      */
    0,                           /* inited */
    &init_class,                 /* init_class */
    &init,                       /* init                      */
    0,                  /* post_init                      */
    &destroy,                    /* free mem                       */
    &dump,                       /* describes himself         */
    0,                /* get length of section     */
    &string_length,              /* get length of string      */
    &value_count,                /* 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      */
    &unpack_long,                /* grib_unpack procedures long    */
    &pack_double,                /* grib_pack procedures double    */
    &unpack_double,              /* grib_unpack procedures double  */
    &pack_string,                /* grib_pack procedures string    */
    &unpack_string,              /* grib_unpack procedures string  */
    0,          /* grib_pack array procedures string    */
    0,        /* grib_unpack array 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    */
    &compare,                    /* compare vs. another accessor   */
    0,     /* unpack only ith value          */
    0,     /* unpack a subarray         */
    0,              		/* clear          */
    0,               		/* clone accessor          */
};


grib_accessor_class* grib_accessor_class_concept = &_grib_accessor_class_concept;


static void init_class(grib_accessor_class* c)
{
	c->next_offset	=	(*(c->super))->next_offset;
	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->pack_string_array	=	(*(c->super))->pack_string_array;
	c->unpack_string_array	=	(*(c->super))->unpack_string_array;
	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->unpack_double_element	=	(*(c->super))->unpack_double_element;
	c->unpack_double_subarray	=	(*(c->super))->unpack_double_subarray;
	c->clear	=	(*(c->super))->clear;
	c->make_clone	=	(*(c->super))->make_clone;
}

/* END_CLASS_IMP */

#define MAX_CONCEPT_STRING_LENGTH 255

/* Note: A fast cut-down version of strcmp which does NOT return -1 */
/* 0 means input strings are equal and 1 means not equal */
GRIB_INLINE static int grib_inline_strcmp(const char* a,const char* b)
{
    if (*a != *b) return 1;
    while((*a!=0 && *b!=0) &&  *(a) == *(b) ) {a++;b++;}
    return (*a==0 && *b==0) ? 0 : 1;
}

static void init(grib_accessor* a, const long len , grib_arguments* args )
{
    a->length = 0;
}

static void dump(grib_accessor* a, grib_dumper* dumper)
{
    grib_dump_string(dumper,a,NULL);
}

static int concept_condition_expression_true(grib_handle* h,grib_concept_condition* c) {
    long lval;
    double dval;
    long lres=0;
    double dres=0.0;
    const char *cval;
    char buf[80];
    char tmp[80];
    size_t len = sizeof(buf);
    size_t size=sizeof(tmp);
    int ok = 0;
    int err=0;
    int type       = grib_expression_native_type(h,c->expression);

    switch(type)
    {
    case GRIB_TYPE_LONG:
        grib_expression_evaluate_long(h,c->expression,&lres);
        ok =  (grib_get_long(h,c->name,&lval) == GRIB_SUCCESS) &&
                (lval == lres);
        break;

    case GRIB_TYPE_DOUBLE:
        grib_expression_evaluate_double(h,c->expression,&dres);
        ok = (grib_get_double(h,c->name,&dval) == GRIB_SUCCESS) &&
                (dval == dres);
        break;

    case GRIB_TYPE_STRING:
        ok = (grib_get_string(h,c->name,buf,&len) == GRIB_SUCCESS) &&
        ((cval = grib_expression_evaluate_string(h,c->expression,tmp,&size,&err)) != NULL) &&
        (err==0) && (grib_inline_strcmp(buf,cval) == 0);
        break;

    default:
        /* TODO: */
        break;
    }
    return ok;
}

static int concept_condition_iarray_true(grib_handle* h,grib_concept_condition* c) {
    long *val;
    size_t size=0,i;
    int ret;
    int err=0;

    err=grib_get_size(h,c->name,&size);
    if (err==0 || size!=grib_iarray_used_size(c->iarray)) return 0;

    val=(long*)grib_context_malloc_clear(h->context,sizeof(long)*size);

    err=grib_get_long_array(h,c->name,val,&size);
    if (err==0) return 0;

    ret=1;
    for (i=0;i<size;i++) {
        if (val[i]!=c->iarray->v[i]) {
            ret=0;
            break;
        }
    }

    return ret;
}

static int concept_condition_true(grib_handle* h,grib_concept_condition* c) {
    if (c->expression==NULL) return concept_condition_iarray_true(h,c);
    else return concept_condition_expression_true(h,c);
}

static const char* concept_evaluate(grib_accessor* a)
{
    int match = 0;
    const char* best = 0;
    /* const char* prev = 0; */
    grib_concept_value*  c = action_concept_get_concept(a);
    grib_handle* h=grib_handle_of_accessor(a);

    while(c)
    {
        grib_concept_condition* e = c->conditions;
        int cnt = 0;
        while(e)
        {
            if(!concept_condition_true(h,e)) break;
            e = e->next;
            cnt++;
        }

        if(e == NULL)
        {
            if(cnt >= match) {
                /* prev  = (cnt > match) ? NULL : best; */
                match = cnt;
                best  = c->name;
            }
        }

        c = c->next;
    }

    return best;
}

#define MAX_NUM_CONCEPT_VALUES 40

static int concept_conditions_expression_apply(grib_handle* h,grib_concept_condition* e,grib_values* values,grib_sarray* sa,int* n)
{
    long lres=0;
    double dres=0.0;
    int count=*n;
    size_t size;
    int err=0;

    Assert(count<1024);
    values[count].name = e->name;

    values[count].type = grib_expression_native_type(h,e->expression);
    switch(values[count].type)
    {
    case GRIB_TYPE_LONG:
        grib_expression_evaluate_long(h,e->expression,&lres);
        values[count].long_value = lres;
        break;
    case GRIB_TYPE_DOUBLE:
        grib_expression_evaluate_double(h,e->expression,&dres);
        values[count].double_value = dres;
        break;
    case GRIB_TYPE_STRING:
        size = sizeof(sa->v[count]);
        values[count].string_value = grib_expression_evaluate_string(h,e->expression,sa->v[count],&size,&err);
        break;
    default:
        return GRIB_NOT_IMPLEMENTED;
        break;
    }
    (*n)++;
    return err;
}

static int concept_conditions_iarray_apply(grib_handle* h,grib_concept_condition* c)
{
    size_t size=grib_iarray_used_size(c->iarray);
    return grib_set_long_array(h,c->name,c->iarray->v,size);
}

static int concept_conditions_apply(grib_handle* h,grib_concept_condition* c,grib_values* values,grib_sarray* sa,int* n)
{
    if (c->expression==NULL) return concept_conditions_iarray_apply(h,c);
    else return concept_conditions_expression_apply(h,c,values,sa,n);
}

static int cmpstringp(const void *p1, const void *p2)
{
    /* The actual arguments to this function are "pointers to
       pointers to char", but strcmp(3) arguments are "pointers
       to char", hence the following cast plus dereference */
    return strcmp(* (char * const *) p1, * (char * const *) p2);
}

static int grib_concept_apply(grib_accessor* a, const char* name)
{
    int err=0;
    int count = 0;
    grib_concept_condition* e=NULL;
    grib_values values[1024];
    grib_sarray* sa=NULL;
    grib_concept_value* c=NULL;
    grib_concept_value*  concepts = action_concept_get_concept(a);
    grib_handle* h=grib_handle_of_accessor(a);
    grib_action* act=a->creator;
    int nofail=action_concept_get_nofail(a);

    Assert(concepts!=NULL);

    c=(grib_concept_value*)grib_trie_get(concepts->index,name);

    if (!c) c=(grib_concept_value*)grib_trie_get(concepts->index,"default");

    if (!c){
        err= nofail ? GRIB_SUCCESS : GRIB_CONCEPT_NO_MATCH;
        if (err) {
            size_t i = 0, concept_count = 0;
            char* all_concept_vals[MAX_NUM_CONCEPT_VALUES] = {NULL,}; /* sorted array containing concept values */
            grib_concept_value* pCon = concepts;

            grib_context_log(h->context,GRIB_LOG_ERROR, "concept: no match for %s=%s", act->name,name);

            /* Create a list of all possible values for this concept and sort it */
            while (pCon) {
                if (i >= MAX_NUM_CONCEPT_VALUES)
                    break;
                all_concept_vals[i++] = pCon->name;
                pCon = pCon->next;
            }
            concept_count = i;
            /* Only print out all concepts if fewer than MAX_NUM_CONCEPT_VALUES.
             * Printing out all values for concepts like paramId would be silly! */
            if (concept_count < MAX_NUM_CONCEPT_VALUES) {
                fprintf(stderr, "Here are the possible values for concept %s:\n", act->name);
                qsort(&all_concept_vals, concept_count, sizeof(char*), cmpstringp);
                for(i=0; i<concept_count; ++i) {
                    if (all_concept_vals[i]) {
                        int print_it = 1;
                        if (i>0 && strcmp(all_concept_vals[i], all_concept_vals[i-1]) == 0) {
                            print_it = 0;  /* skip duplicate entries */
                        }
                        if (print_it) fprintf(stderr, "\t%s\n", all_concept_vals[i]);
                    }
                }
            }
        }
        return err;
    }
    e = c->conditions;
    sa=grib_sarray_new(h->context,10,10);
    while(e)
    {
        concept_conditions_apply(h,e,values,sa,&count);
        e = e->next;
    }
    grib_sarray_delete(h->context,sa);

    if (count) err=grib_set_values(h,values,count);
    return err;
}

static int pack_double(grib_accessor* a, const double* val, size_t *len)
{
    return GRIB_NOT_IMPLEMENTED;
}

static int pack_long(grib_accessor* a, const long* val, size_t *len)
{
    char buf[80];
    size_t s;
    sprintf(buf,"%ld",*val);
#if 0
    if(*len > 1)
        return GRIB_NOT_IMPLEMENTED;
#endif
    s = strlen(buf)+1;
    return pack_string(a,buf,&s);
}

static int unpack_double(grib_accessor* a, double* val, size_t *len)
{
    /*
     * If we want to have a condition which contains tests for paramId as well
     * as a floating point key, then need to be able to evaluate paramId as a
     * double. E.g.
     *   if (referenceValue > 0 && paramId == 129)
     */
    /*return GRIB_NOT_IMPLEMENTED*/
    long lval = 0;
    int ret = unpack_long(a, &lval, len);
    if (ret == GRIB_SUCCESS) {
        *val = lval;
    }
    return ret;
}

static int unpack_long(grib_accessor* a, long* val, size_t *len)
{
    /* TODO properly calling concept_evaluate_long ! */
    const char *p = concept_evaluate(a);

    if(!p) {
        if (a->creator->defaultkey)
            return grib_get_long_internal(grib_handle_of_accessor(a),a->creator->defaultkey,val);

        return GRIB_NOT_FOUND;
    }

    *val = atol(p);
    *len = 1;

    return GRIB_SUCCESS;
}

static int get_native_type(grib_accessor* a)
{
    int type=GRIB_TYPE_STRING;
    if (a->flags & GRIB_ACCESSOR_FLAG_LONG_TYPE)
        type=GRIB_TYPE_LONG;

    return type;
}

static void destroy(grib_context* c,grib_accessor* a)
{
    /*
     * grib_accessor_concept *self = (grib_accessor_concept*)a;
     * grib_context_free(c,self->cval);
     */
}

static int unpack_string (grib_accessor* a, char* val, size_t *len)
{
    size_t slen ;
    const char *p = concept_evaluate(a);

    if(!p) {
        if (a->creator->defaultkey)
            return grib_get_string_internal(grib_handle_of_accessor(a),a->creator->defaultkey,val,len);

        return GRIB_NOT_FOUND;
    }

    slen = strlen(p) +1;
    if(*len < slen)
    {
        grib_context_log(a->context, GRIB_LOG_ERROR, "Variable unpack_string Wrong size for %s it is %d bytes big (len=%d)", a->name , slen ,*len);
        *len = slen;
        return GRIB_BUFFER_TOO_SMALL;
    }
    strcpy(val,p);
    *len = slen;
    return GRIB_SUCCESS;
}

static int pack_string(grib_accessor* a, const char* val, size_t *len)
{
    return  grib_concept_apply(a,val);
}

static size_t string_length(grib_accessor* a)
{
    return MAX_CONCEPT_STRING_LENGTH;
}

static int value_count(grib_accessor* a,long* count)
{
    *count=1;
    return 0;
}

static int compare(grib_accessor* a,grib_accessor* b)
{
    int retval=0;
    char *aval=0;
    char *bval=0;

    size_t alen = 0;
    size_t blen = 0;
    int err=0;
    long count=0;

    err=grib_value_count(a,&count);
    if (err) return err;
    alen=count;

    err=grib_value_count(b,&count);
    if (err) return err;
    blen=count;

    if (alen != blen) return GRIB_COUNT_MISMATCH;

    aval=(char*)grib_context_malloc(a->context,alen*sizeof(char));
    bval=(char*)grib_context_malloc(b->context,blen*sizeof(char));

    grib_unpack_string(a,aval,&alen);
    grib_unpack_string(b,bval,&blen);

    retval = GRIB_SUCCESS;
    if (!aval || !bval || grib_inline_strcmp(aval,bval)) retval = GRIB_STRING_VALUE_MISMATCH;

    grib_context_free(a->context,aval);
    grib_context_free(b->context,bval);

    return retval;
}
