/* -*- c-basic-offset: 2 -*- */
/*
  Copyright(C) 2009-2018 Brazil
  Copyright(C) 2018 Kouhei Sutou <kou@clear-code.com>

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License version 2.1 as published by the Free Software Foundation.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#pragma once

#include "grn.h"
#include "grn_db.h"
#include "grn_hash.h"
#include "grn_table.h"

#ifdef __cplusplus
extern "C" {
#endif

#define GRN_PAT_MAX_KEY_SIZE                    GRN_TABLE_MAX_KEY_SIZE
#define GRN_PAT_MAX_TOTAL_KEY_SIZE              (UINT32_MAX - 1)

struct _grn_pat {
  grn_db_obj obj;
  grn_io *io;
  struct grn_pat_header *header;
  grn_encoding encoding;
  uint32_t key_size;
  uint32_t value_size;
  grn_table_module tokenizer;
  grn_table_module normalizer;
  grn_obj token_filters;
  /* For backward compatibility */
  grn_obj token_filter_procs;
  grn_id *cache;
  uint32_t cache_size;
  grn_bool is_dirty;
  grn_critical_section lock;
};

#define GRN_PAT_NDELINFOS 0x100

typedef struct {
  grn_id d;        /* The ID of a deleting node. */
  grn_id ld;       /* The ID of the parent node of a deleting node. */
                   /* delinfo->ld is set if required. */
  uint32_t stat;   /* DL_EMPTY, DL_PHASE1, or DL_PHASE2. */
  uint32_t shared; /* This flag is used if GRN_OBJ_KEY_WITH_SIS is set. */
} grn_pat_delinfo;

struct grn_pat_header {
  uint32_t flags;
  grn_encoding encoding;
  uint32_t key_size;
  uint32_t value_size;
  grn_id tokenizer;
  uint32_t n_entries;
  uint32_t curr_rec;
  int32_t curr_key;
  int32_t curr_del;
  int32_t curr_del2;
  int32_t curr_del3;
  uint32_t n_garbages;
  grn_id normalizer;
  uint32_t truncated;
  uint32_t n_dirty_opens;
  uint32_t reserved[1002];
  grn_pat_delinfo delinfos[GRN_PAT_NDELINFOS];
  grn_id garbages[GRN_PAT_MAX_KEY_SIZE + 1];
};

struct _grn_pat_cursor_entry {
  grn_id id;
  uint16_t check;
};

typedef struct _grn_pat_cursor_entry grn_pat_cursor_entry;

struct _grn_pat_cursor {
  grn_db_obj obj;
  grn_id curr_rec;   /* ID of the latest record */
  grn_pat *pat;
  grn_ctx *ctx;
  unsigned int size; /* stack size (the maximum number of entries) */
  unsigned int sp;   /* stack pointer (the number of entries) */
  grn_id tail;       /* sentinel (the end of the traversal) */
  unsigned int rest; /* limit rest (the number of remaining records) */
  grn_pat_cursor_entry *ss; /* stack buffer (pointer to entries) */
  uint8_t curr_key[GRN_TABLE_MAX_KEY_SIZE];
};

GRN_API grn_id grn_pat_curr_id(grn_ctx *ctx, grn_pat *pat);

/* private */
GRN_API grn_rc grn_pat_truncate(grn_ctx *ctx, grn_pat *pat);
const char *_grn_pat_key(grn_ctx *ctx, grn_pat *pat, grn_id id, uint32_t *key_size);
grn_id grn_pat_next(grn_ctx *ctx, grn_pat *pat, grn_id id);
const char *grn_pat_get_value_(grn_ctx *ctx, grn_pat *pat, grn_id id, uint32_t *size);
GRN_API grn_id grn_pat_at(grn_ctx *ctx, grn_pat *pat, grn_id id);
void grn_pat_check(grn_ctx *ctx, grn_pat *pat);
void grn_pat_inspect_nodes(grn_ctx *ctx, grn_pat *pat, grn_obj *buf);
void grn_pat_cursor_inspect(grn_ctx *ctx, grn_pat_cursor *c, grn_obj *buf);

grn_rc grn_pat_cache_enable(grn_ctx *ctx, grn_pat *pat, uint32_t cache_size);
void grn_pat_cache_disable(grn_ctx *ctx, grn_pat *pat);

GRN_API grn_rc grn_pat_fuzzy_search(grn_ctx *ctx, grn_pat *pat,
                                    const void *key, unsigned int key_size,
                                    grn_fuzzy_search_optarg *args, grn_hash *h);

uint32_t grn_pat_total_key_size(grn_ctx *ctx, grn_pat *pat);

grn_bool grn_pat_is_key_encoded(grn_ctx *ctx, grn_pat *pat);

grn_rc grn_pat_dirty(grn_ctx *ctx, grn_pat *pat);
grn_bool grn_pat_is_dirty(grn_ctx *ctx, grn_pat *pat);
grn_rc grn_pat_clean(grn_ctx *ctx, grn_pat *pat);
grn_rc grn_pat_clear_dirty(grn_ctx *ctx, grn_pat *pat);

#ifdef __cplusplus
}
#endif
