/*
 * (C) Copyright 2005- 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"

/* 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;
}

grib_keys_iterator* grib_keys_iterator_new(grib_handle* h, unsigned long filter_flags, const char* name_space)
{
    grib_keys_iterator* ki = NULL;

    if (!h)
        return NULL;

    /*if (h->product_kind == PRODUCT_BUFR) {
        grib_context_log(h->context, GRIB_LOG_ERROR,
                         "Invalid keys iterator for BUFR message: please use codes_bufr_keys_iterator_new");
        return NULL;
    }*/

    ki = (grib_keys_iterator*)grib_context_malloc_clear(h->context, sizeof(grib_keys_iterator));
    if (!ki)
        return NULL;

    ki->filter_flags = filter_flags;
    ki->handle       = h;
    ki->name_space   = NULL;

    if (name_space != NULL && strlen(name_space) > 0)
        ki->name_space = grib_context_strdup(h->context, name_space);

    ki->at_start = 1;
    ki->match    = 0;

    grib_keys_iterator_set_flags(ki, filter_flags);

    return ki;
}

int grib_keys_iterator_set_flags(grib_keys_iterator* ki, unsigned long flags)
{
    int ret = 0;
    grib_handle* h;

    if (!ki)
        return GRIB_INTERNAL_ERROR;

    h = ki->handle;

    if ((flags & GRIB_KEYS_ITERATOR_SKIP_DUPLICATES) && ki->seen == NULL)
        ki->seen = grib_trie_new(h->context);

    /* GRIB-566 */
    if (flags & GRIB_KEYS_ITERATOR_SKIP_COMPUTED)
        ki->filter_flags |= GRIB_KEYS_ITERATOR_SKIP_COMPUTED;
    if (flags & GRIB_KEYS_ITERATOR_SKIP_CODED)
        ki->filter_flags |= GRIB_KEYS_ITERATOR_SKIP_CODED;

    if (flags & GRIB_KEYS_ITERATOR_SKIP_FUNCTION)
        ki->accessor_flags_skip |= GRIB_ACCESSOR_FLAG_FUNCTION;

    if (flags & GRIB_KEYS_ITERATOR_SKIP_READ_ONLY)
        ki->accessor_flags_skip |= GRIB_ACCESSOR_FLAG_READ_ONLY;

    if (flags & GRIB_KEYS_ITERATOR_SKIP_EDITION_SPECIFIC)
        ki->accessor_flags_skip |= GRIB_ACCESSOR_FLAG_EDITION_SPECIFIC;

    return ret;
}

static void mark_seen(grib_keys_iterator* ki, const char* name)
{
    /* See GRIB-932 */
    char* tmp = grib_context_strdup(ki->handle->context, name);
    grib_trie_insert(ki->seen, tmp, (void*)tmp);

    /* grib_trie_insert(ki->seen,name,(void*)name); */
}

static int was_seen(grib_keys_iterator* ki, const char* name)
{
    return grib_trie_get(ki->seen, name) != NULL;
}

int grib_keys_iterator_rewind(grib_keys_iterator* ki)
{
    ki->at_start = 1;
    return GRIB_SUCCESS;
}

static int skip(grib_keys_iterator* kiter)
{
    /* TODO: set the section to hidden, to speed up that */
    /* if(grib_get_sub_section(kiter->current)) */
    if (kiter->current->sub_section_)
        return 1;

    if (kiter->current->flags_ & GRIB_ACCESSOR_FLAG_HIDDEN)
        return 1;

    if (kiter->current->flags_ & kiter->accessor_flags_skip)
        return 1;

    if ((kiter->filter_flags & GRIB_KEYS_ITERATOR_SKIP_COMPUTED) && kiter->current->length_ == 0)
        return 1;

    if ((kiter->filter_flags & GRIB_KEYS_ITERATOR_SKIP_CODED) && kiter->current->length_ != 0)
        return 1;

    if (kiter->name_space) {
        kiter->match = 0;

        while (kiter->match < MAX_ACCESSOR_NAMES) {
            if (kiter->current->all_name_spaces_[kiter->match] != NULL) {
                if (grib_inline_strcmp(kiter->current->all_name_spaces_[kiter->match], kiter->name_space) == 0) {
                    if (kiter->seen) {
                        if (was_seen(kiter, kiter->current->all_names_[kiter->match]))
                            return 1;
                        mark_seen(kiter, kiter->current->all_names_[kiter->match]);
                    }
                    return 0;
                }
            }
            kiter->match++;
        }

        return 1;
    }

    if (kiter->seen) {
        if (was_seen(kiter, kiter->current->name_))
            return 1;
        mark_seen(kiter, kiter->current->name_);
    }

    /* ECC-1410 */
    if (kiter->current->all_names_[0] == NULL)
        return 1;

    return 0;
}

int grib_keys_iterator_next(grib_keys_iterator* kiter)
{
    if (kiter->at_start) {
        kiter->current  = kiter->handle->root->block->first;
        kiter->at_start = 0;
    }
    else {
        kiter->current = kiter->current->next_accessor();
    }

    while (kiter->current && skip(kiter))
        kiter->current = kiter->current->next_accessor();

    return kiter->current != NULL;
}

const char* grib_keys_iterator_get_name(const grib_keys_iterator* kiter)
{
    /* if(kiter->name_space) */
    Assert(kiter->current);
    return kiter->current->all_names_[kiter->match];
}

grib_accessor* grib_keys_iterator_get_accessor(grib_keys_iterator* kiter)
{
    return kiter->current;
}

int grib_keys_iterator_delete(grib_keys_iterator* kiter)
{
    if (kiter) {
        if (kiter->seen)
            grib_trie_delete(kiter->seen);
        if (kiter->name_space)
            grib_context_free(kiter->handle->context, kiter->name_space);
        grib_context_free(kiter->handle->context, kiter);
    }
    return 0;
}

int grib_keys_iterator_get_long(const grib_keys_iterator* kiter, long* v, size_t* len)
{
    return kiter->current->unpack_long(v, len);
}

int grib_keys_iterator_get_double(const grib_keys_iterator* kiter, double* v, size_t* len)
{
    return kiter->current->unpack_double(v, len);
}
int grib_keys_iterator_get_float(const grib_keys_iterator* kiter, float* v, size_t* len)
{
    return kiter->current->unpack_float(v, len);
}

int grib_keys_iterator_get_string(const grib_keys_iterator* kiter, char* v, size_t* len)
{
    return kiter->current->unpack_string(v, len);
}

int grib_keys_iterator_get_bytes(const grib_keys_iterator* kiter, unsigned char* v, size_t* len)
{
    return kiter->current->unpack_bytes(v, len);
}

int grib_keys_iterator_get_native_type(const grib_keys_iterator* kiter)
{
    return kiter->current->get_native_type();
}