#pragma once

#include <string>
#include <vector>
#include <art.h>
#include <sparsepp.h>
#include <store.h>
#include <topster.h>
#include <json.hpp>
#include <field.h>

class Collection {
private:
    Store* store;

    std::string name;

    spp::sparse_hash_map<std::string, field> schema;

    // Integer ID used internally for bitmaps - not exposed to the client
    uint32_t seq_id;

    spp::sparse_hash_map<std::string, art_tree*> index_map;

    spp::sparse_hash_map<uint32_t, uint16_t> doc_scores;

    uint32_t next_seq_id();

    const std::string SEQ_ID_PREFIX = "SQ_";
    const std::string ID_PREFIX = "ID_";
    const std::string META_PREFIX = "MT_";

    const std::string FIELDS_KEY = META_PREFIX + "_fields";

    std::string get_seq_id_key(uint32_t seq_id);
    std::string get_id_key(std::string id);

    static inline std::vector<art_leaf *> next_suggestion(const std::vector<std::vector<art_leaf *>> &token_leaves,
                                                          long long int n);
    void log_leaves(const int cost, const std::string &token, const std::vector<art_leaf *> &leaves) const;

    void search_candidates(std::vector<std::vector<art_leaf*>> & token_leaves, std::vector<nlohmann::json> & results,
                           spp::sparse_hash_set<uint64_t> & dedup_seq_ids, size_t & total_results, const size_t & max_results);

    void index_string_field(const std::string &field_name, art_tree *t, const nlohmann::json &document, uint32_t seq_id) const;

    void index_int32_field(const std::string &field_name, art_tree *t, const nlohmann::json &document, uint32_t seq_id) const;

public:
    Collection() = delete;
    Collection(const std::string & state_dir_path, const std::string & name, const std::vector<field> & fields);
    ~Collection();
    std::string add(std::string json_str);
    std::vector<nlohmann::json> search(std::string query, const int num_typos, const size_t num_results,
                                       const token_ordering token_order = FREQUENCY, const bool prefix = false);
    void remove(std::string id);
    void score_results(Topster<100> &topster, const std::vector<art_leaf *> &query_suggestion,
                       const uint32_t *result_ids,
                       const size_t result_size) const;

    enum {MAX_SEARCH_TOKENS = 20};
    enum {MAX_RESULTS = 100};
};