#ifndef _ZoO_KNOWLEDGE_KNOWLEDGE_H_
#define _ZoO_KNOWLEDGE_KNOWLEDGE_H_

#include "../core/char_types.h"
#include "../core/index_types.h"

#include "knowledge_types.h"

void ZoO_knowledge_initialize (struct ZoO_knowledge k [const restrict static 1]);

void ZoO_knowledge_finalize (struct ZoO_knowledge k [const restrict static 1]);

/*
 * When returning 0:
 *    {word} was added to {k}, or was already there.
 *    {*result} indicates where {word} is in {k->words}.
 *
 * When returning -1:
 *    Something went wrong when adding the occurrence of {word} to {k}.
 *    {k} remains semantically unchanged.
 *    {*result} may or may not have been altered.
 */
int ZoO_knowledge_learn_word
(
   struct ZoO_knowledge k [const static 1],
   const ZoO_char word [const restrict static 1],
   const ZoO_index word_length,
   ZoO_index result [const restrict static 1]
);

int ZoO_knowledge_learn_sequence
(
   struct ZoO_knowledge k [const restrict static 1],
   const ZoO_index sequence [const restrict static 1],
   const ZoO_index sequence_length,
   const ZoO_index markov_order
);

int ZoO_knowledge_learn_markov_sequence
(
   struct ZoO_knowledge k [const restrict static 1],
   const ZoO_index sequence [const restrict static 1],
   const ZoO_index sequence_length,
   const ZoO_index markov_order
);

int ZoO_knowledge_get_following_sequences_ref
(
   const struct ZoO_knowledge k [const static 1],
   const ZoO_index initial_word,
   const ZoO_index * restrict following_sequences_ref [const restrict static 1],
   const ZoO_index * restrict following_sequences_weights [const restrict static 1],
   ZoO_index following_sequences_weights_sum [const static 1]
);

int ZoO_knowledge_get_sequence
(
   const struct ZoO_knowledge k [const static 1],
   const ZoO_index sequences_ref,
   const ZoO_index * restrict sequence [const restrict static 1]
);

int ZoO_knowledge_get_word
(
   const struct ZoO_knowledge k [const static 1],
   const ZoO_index word_ref,
   const ZoO_char * word [const restrict static 1],
   size_t word_size [const restrict static 1]
);

/*
 * When returning 0:
 *    {word} is in {k}.
 *    {word} is located at {k->words[*result]}.
 *
 * When returning -1:
 *    {word} is not in {k}.
 *    {*result} is where {word} was expected to be found in
 *    {k->sorted_indices}.
 */
int ZoO_knowledge_find_word_id
(
   const struct ZoO_knowledge k [const restrict static 1],
   const ZoO_char word [const restrict static 1],
   const size_t word_size,
   ZoO_index result [const restrict static 1]
);

int ZoO_knowledge_find_preceding_words
(
   const struct ZoO_knowledge k [const static 1],
   const ZoO_index sequence [const restrict],
   const ZoO_index markov_order,
   const ZoO_index * restrict preceding_words [const restrict static 1],
   const ZoO_index * restrict preceding_words_weights [const restrict static 1],
   ZoO_index preceding_words_weights_sum [const restrict static 1]
);

int ZoO_knowledge_find_following_words
(
   const struct ZoO_knowledge k [const static 1],
   const ZoO_index sequence [const restrict],
   const ZoO_index sequence_length,
   const ZoO_index markov_order,
   const ZoO_index * restrict following_words [const restrict static 1],
   const ZoO_index * restrict following_words_weights [const restrict static 1],
   ZoO_index following_words_weights_sum [const restrict static 1]
);

#endif