/* -*- c-basic-offset: 2 -*- */
/*
  Copyright(C) 2009-2016 Brazil
  Copyright(C) 2019 Sutou Kouhei <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_ctx.h"
#include "grn_hash.h"
#include "grn_io.h"

#ifdef __cplusplus
extern "C" {
#endif

/**** fixed sized elements ****/

typedef struct _grn_ra grn_ra;

struct _grn_ra {
  grn_db_obj obj;
  grn_io *io;
  int element_width;
  int element_mask;
  struct grn_ra_header *header;
};

struct grn_ra_header {
  uint32_t element_size;
  uint32_t nrecords; /* nrecords is not maintained by default */
  grn_column_flags flags;
  uint32_t reserved[9];
};

grn_ra *grn_ra_create(grn_ctx *ctx, const char *path, unsigned int element_size);
grn_ra *grn_ra_open(grn_ctx *ctx, const char *path);
grn_rc grn_ra_info(grn_ctx *ctx, grn_ra *ra, unsigned int *element_size);
grn_rc grn_ra_close(grn_ctx *ctx, grn_ra *ra);
grn_rc grn_ra_remove(grn_ctx *ctx, const char *path);
void *grn_ra_ref(grn_ctx *ctx, grn_ra *ra, grn_id id);
grn_rc grn_ra_unref(grn_ctx *ctx, grn_ra *ra, grn_id id);

typedef struct _grn_ra_cache grn_ra_cache;

struct _grn_ra_cache {
  void *p;
  int32_t seg;
};

#define GRN_RA_CACHE_INIT(ra,c) do {\
  (c)->p = NULL; (c)->seg = -1;\
} while (0)

#define GRN_RA_CACHE_FIN(ra,c) do {\
  if ((c)->seg != -1) { GRN_IO_SEG_UNREF((ra)->io, (c)->seg); }\
} while (0);

void *grn_ra_ref_cache(grn_ctx *ctx, grn_ra *ra, grn_id id, grn_ra_cache *cache);

/**** variable sized elements ****/

typedef struct _grn_ja grn_ja;

struct _grn_ja {
  grn_db_obj obj;
  grn_io *io;
  struct grn_ja_header *header;
};

GRN_API grn_ja *grn_ja_create(grn_ctx *ctx, const char *path,
                              uint32_t max_element_size, uint32_t flags);
grn_ja *grn_ja_open(grn_ctx *ctx, const char *path);
grn_rc grn_ja_info(grn_ctx *ctx, grn_ja *ja, unsigned int *max_element_size);
grn_column_flags grn_ja_get_flags(grn_ctx *ctx, grn_ja *ja);
GRN_API grn_rc grn_ja_close(grn_ctx *ctx, grn_ja *ja);
grn_rc grn_ja_remove(grn_ctx *ctx, const char *path);
grn_rc grn_ja_put(grn_ctx *ctx, grn_ja *ja, grn_id id,
                  void *value, uint32_t value_len, int flags, uint64_t *cas);
int grn_ja_at(grn_ctx *ctx, grn_ja *ja, grn_id id, void *valbuf, int buf_size);

GRN_API void *grn_ja_ref(grn_ctx *ctx, grn_ja *ja, grn_id id, grn_io_win *iw,
                         uint32_t *value_len);
grn_obj *grn_ja_get_value(grn_ctx *ctx, grn_ja *ja, grn_id id, grn_obj *value);

GRN_API grn_rc grn_ja_unref(grn_ctx *ctx, grn_io_win *iw);
int grn_ja_defrag(grn_ctx *ctx, grn_ja *ja, int threshold);

GRN_API grn_rc grn_ja_putv(grn_ctx *ctx, grn_ja *ja, grn_id id,
                           grn_obj *vector, int flags);
GRN_API uint32_t grn_ja_size(grn_ctx *ctx, grn_ja *ja, grn_id id);

void grn_ja_check(grn_ctx *ctx, grn_ja *ja);

#define GRN_JA_READER_INITIAL_REF_SEG_IDS_SIZE 16

/*
 * grn_ja_reader is designed to improve the performance of sequential access.
 */
typedef struct {
  grn_ja *ja;                /* Target jagged array (without ref. count). */
  uint32_t einfo_seg_id;     /* ID of the current header segment. */
  void *einfo_seg_addr;      /* Address of the current header segment. */
  void *einfo;               /* Header of the current value. */
  grn_bool ref_avail;        /* grn_ja_reader_ref() is available or not. */
  uint32_t ref_seg_id;       /* ID of the current referenced segment. */
  void *ref_seg_addr;        /* Address of the current referenced segment. */
  uint32_t *ref_seg_ids;     /* IDs of referenced segments. */
  uint32_t nref_seg_ids;     /* Number of referenced segments. */
  uint32_t ref_seg_ids_size; /* Maximum number of referenced segments. */
  uint32_t body_seg_id;      /* ID of the current body segment. */
  uint32_t body_seg_offset;  /* Offset in the current body segment. */
  void *body_seg_addr;       /* Address of the current body segment. */
  uint32_t value_size;       /* Size of the current value. */
  uint32_t packed_size;      /* Compressed size of the current value. */
  void *packed_buf;          /* Buffer for decompression. */
  uint32_t packed_buf_size;  /* Size of the buffer for decompression. */
  void *stream;              /* Stream of a compression library. */
} grn_ja_reader;

/*
 * grn_ja_reader_init() initializes a reader.
 * An initialized reader must be finalized by grn_ja_reader_fin().
 */
grn_rc grn_ja_reader_init(grn_ctx *ctx, grn_ja_reader *reader, grn_ja *ja);

/* grn_ja_reader_fin() finalizes a reader. */
grn_rc grn_ja_reader_fin(grn_ctx *ctx, grn_ja_reader *reader);

/*
 * grn_ja_reader_open() creates a reader.
 * A created reader must be destroyed by grn_ja_reader_close().
 */
grn_rc grn_ja_reader_open(grn_ctx *ctx, grn_ja *ja, grn_ja_reader **reader);

/* grn_ja_reader_close() destroys a reader. */
grn_rc grn_ja_reader_close(grn_ctx *ctx, grn_ja_reader *reader);

/*
 * grn_ja_reader_seek() prepares to access a value specified by `id`.
 * On success, `reader->value_size` is set.
 */
grn_rc grn_ja_reader_seek(grn_ctx *ctx, grn_ja_reader *reader, grn_id id);

/*
 * grn_ja_reader_ref() gets the address to the current value.
 * This function is available if `reader->ref_avail` is true.
 */
grn_rc grn_ja_reader_ref(grn_ctx *ctx, grn_ja_reader *reader, void **addr);

/* grn_ja_reader_unref() frees refereces returned by grn_ja_reader_ref(). */
grn_rc grn_ja_reader_unref(grn_ctx *ctx, grn_ja_reader *reader);

/* grn_ja_reader_read() reads the current value to `buf`. */
grn_rc grn_ja_reader_read(grn_ctx *ctx, grn_ja_reader *reader, void *buf);

/*
 * grn_ja_reader_pread() reads a part of the current value to `buf`.
 * If `offset` and `size` are invalid, the behavior is undefined.
 * FIXME: Compressed values are not supported yet.
 */
grn_rc grn_ja_reader_pread(grn_ctx *ctx, grn_ja_reader *reader,
                           size_t offset, size_t size, void *buf);

/*
typedef struct _grn_vgram_vnode
{
  struct _grn_vgram_vnode *car;
  struct _grn_vgram_vnode *cdr;
  grn_id tid;
  grn_id vid;
  int freq;
  int len;
} grn_vgram_vnode;

typedef struct _grn_vgram grn_vgram;
struct _grn_vgram {
  void *vgram;
};

struct _grn_vgram_buf {
  size_t len;
  grn_id *tvs;
  grn_id *tvp;
  grn_id *tve;
  grn_vgram_vnode *vps;
  grn_vgram_vnode *vpp;
  grn_vgram_vnode *vpe;
};

grn_vgram *grn_vgram_create(const char *path);
grn_vgram *grn_vgram_open(const char *path);
grn_rc grn_vgram_close(grn_vgram *vgram);
grn_rc grn_vgram_update(grn_vgram *vgram, grn_id rid, grn_vgram_buf *b, grn_hash *terms);

grn_vgram_buf *grn_vgram_buf_open(size_t len);
grn_rc grn_vgram_buf_add(grn_vgram_buf *b, grn_id tid);
grn_rc grn_vgram_buf_close(grn_vgram_buf *b);

*/

#ifdef __cplusplus
}
#endif
