(sc-comment
  "this file contains declarations and macros to include for using sph-dg as a shared library.")

(pre-include-once
  lmdb-h "lmdb.h")

(sc-include-once
  sph "foreign/sph"
  sph-dg-status "main/lib/status"
  sph-dg-config "main/config")

(sc-comment
  "data size is limited by lmdb max keysize, which is 511 byte by lmdb default but can be adjusted with recompiling lmdb")

(pre-define-if-not-defined
  dg-id-t
  b64
  dg-ordinal-t
  b32
  dg-id-max
  UINT64_MAX
  dg-size-octets-data-max
  511
  dg-size-octets-data-min
  1 dg-size-octets-id (sizeof dg-id-t) dg-size-octets-ordinal (sizeof dg-ordinal-t))

(pre-define-if-not-defined (dg-id-equal? a b) (= a b))
(pre-define-if-not-defined (dg-id-compare a b) (if* (< a b) -1 (> a b)))
(pre-define dg-ordinal-compare dg-id-compare)
(pre-define-if-not-defined (dg-pointer->id a index) (deref (+ index (convert-type a dg-id-t*))))

(pre-define
  imht-set-key-t dg-id-t
  dg-type-id 0
  dg-type-intern 1
  dg-type-extern 2
  dg-type-intern-small 3
  dg-type-mask 3
  dg-id-type-step 4
  dg-size-octets-relation-data (+ dg-size-octets-ordinal dg-size-octets-id)
  dg-size-octets-relation-key (* 2 dg-size-octets-id)
  dg-read-option-skip 1
  dg-read-option-is-set-left 2
  dg-read-option-is-set-right 4
  dg-read-option-initialised 8
  dg-null 0
  ; dg-type-bit-* are used as filter arguments for dg-node-select for example
  dg-type-bit-id 1
  dg-type-bit-intern 2
  dg-type-bit-extern 4
  dg-type-bit-intern-small 8)

(sc-include "foreign/sph/imht-set")

(define-type dg-data-t
  (struct
    (data b0*)
    (size size-t)))

(define-type dg-data-record-t
  (struct
    (id dg-id-t)
    (size size-t)
    (data b0*)))

(define-type dg-relation-record-t
  (struct
    (left dg-id-t)
    (right dg-id-t)
    (label dg-id-t)
    (ordinal dg-ordinal-t)))

(pre-define
  mi-list-name-prefix dg-ids
  mi-list-element-t dg-id-t)

(sc-include "foreign/sph/mi-list")

(pre-define
  mi-list-name-prefix dg-data-list
  mi-list-element-t dg-data-t)

(sc-include "foreign/sph/mi-list")

(pre-define
  mi-list-name-prefix dg-data-records
  mi-list-element-t dg-data-record-t)

(sc-include "foreign/sph/mi-list")

(pre-define
  mi-list-name-prefix dg-relation-records
  mi-list-element-t dg-relation-record-t)

(sc-include "foreign/sph/mi-list")

(pre-define
  dg-ids-first mi-list-first
  dg-ids-first-address mi-list-first-address
  dg-ids-rest mi-list-rest
  dg-data-list-first mi-list-first
  dg-data-list-first-address mi-list-first-address
  dg-data-list-rest mi-list-rest
  dg-data-records-first mi-list-first
  dg-data-records-first-address mi-list-first-address
  dg-data-records-rest mi-list-rest
  dg-relation-records-first mi-list-first
  dg-relation-records-first-address mi-list-first-address
  dg-relation-records-rest mi-list-rest)

(define-type dg-txn-t MDB-txn)
(pre-define dg-txn-introduce (define dg-txn dg-txn-t* 0))

(pre-define dg-txn-begin
  (dg-mdb-status-require! (mdb-txn-begin dg-mdb-env 0 MDB-RDONLY (address-of dg-txn))))

(pre-define
  dg-txn-abort (mdb-txn-abort dg-txn) (set dg-txn 0))

(pre-define
  dg-txn-commit (dg-mdb-status-require! (mdb-txn-commit dg-txn)) (set dg-txn 0))

(pre-define dg-txn-write-begin
  (dg-mdb-status-require! (mdb-txn-begin dg-mdb-env 0 0 (address-of dg-txn))))

(pre-define (dg-intern-small-id->data id)
  ;dg-id-t -> dg-id-t
  (bit-shift-right id 2))

(pre-define (dg-intern-small-data->id data)
  ;dg-id-t -> dg-id-t
  (bit-and dg-type-intern-small (bit-shift-left data 2)))

(define-type dg-statistics-t
  (struct
    (id->data MDB-stat)
    (data-intern->id MDB-stat)
    (data-extern->extern MDB-stat)
    (left->right MDB-stat)
    (right->left MDB-stat)
    (label->left MDB-stat)))

(define-type dg-init-options-t
  (struct
    (read-only? b8)
    (maximum-size-octets size-t)
    (maximum-reader-count b32)
    (filesystem-has-ordered-writes? b8)
    (env-open-flags b32)
    (file-permissions b16)))

(define-type dg-index-errors-relation-t
  (struct
    (errors? boolean)
    (missing-right-left dg-relation-records-t*)
    (missing-label-left dg-relation-records-t*)
    (excess-right-left dg-relation-records-t*)
    (excess-label-left dg-relation-records-t*)))

(define-type dg-index-errors-intern-t
  (struct
    (errors? boolean)
    (different-data-id dg-ids-t*)
    (excess-data-id dg-ids-t*)
    (different-id-data dg-ids-t*)
    (missing-id-data dg-ids-t*)))

(define-type dg-index-errors-extern-t
  (struct
    (errors? boolean)
    (different-data-extern dg-ids-t*)
    (excess-data-extern dg-ids-t*)
    (different-id-data dg-ids-t*)
    (missing-id-data dg-ids-t*)))

(define dg-index-errors-relation-null dg-index-errors-relation-t (struct-literal 0 0 0 0 0))
(define dg-index-errors-intern-null dg-index-errors-intern-t (struct-literal 0 0 0 0 0))
(define dg-index-errors-extern-null dg-index-errors-extern-t (struct-literal 0 0 0 0 0))

(define-type dg-ordinal-match-data-t
  (struct
    (min dg-ordinal-t)
    (max dg-ordinal-t)))

(define-type dg-node-read-state-t
  (struct
    (status status-t)
    (cursor (MDB-cursor* restrict))
    (types b8)
    (options b8)))

(define-type dg-intern-read-state-t
  (struct
    (status status-t)
    (cursor (MDB-cursor* restrict))
    (options b8)))

(define-type dg-relation-read-state-t
  (struct
    (status status-t)
    (cursor (MDB-cursor* restrict))
    (cursor-2 (MDB-cursor* restrict))
    (left b0*)
    (right b0*)
    (label b0*)
    (left-first dg-ids-t*)
    (right-first dg-ids-t*)
    (ordinal dg-ordinal-match-data-t*)
    (options b8)
    (reader b0*)))

(define-type dg-relation-reader-t
  (function-pointer status-t dg-relation-read-state-t* b32 dg-relation-records-t**))

(define-type dg-relation-ordinal-generator-t (function-pointer dg-ordinal-t b0*))
(pre-define (dg-type? dg-type-name id) (= dg-type-name (bit-and id dg-type-mask)))
(define (dg-node-read state count result) (status-t dg-node-read-state-t* b32 dg-data-records-t**))
(define (dg-node-select txn types offset state) (status-t dg-txn-t* b8 b32 dg-node-read-state-t*))
(define (dg-node-selection-destroy state) (b0 dg-node-read-state-t*))
(define (dg-relation-selection-destroy state) (b0 dg-relation-read-state-t*))

(define (dg-intern-data->id txn data every? result)
  (status-t dg-txn-t* dg-data-list-t* boolean dg-ids-t**))

(define (dg-intern-ensure txn data result) (status-t dg-txn-t* dg-data-list-t* dg-ids-t**))
(define (dg-intern-update txn id data) (status-t dg-txn-t* dg-id-t dg-data-t))
(define (dg-extern-update txn id data) (status-t dg-txn-t* dg-id-t dg-data-t))

(define (dg-intern-id->data txn ids every? result)
  (status-t dg-txn-t* dg-ids-t* boolean dg-data-list-t**))

(define (dg-exit) b0)
(define (dg-extern-create txn count data result) (status-t dg-txn-t* b32 dg-data-t* dg-ids-t**))

(define (dg-extern-id->data txn ids every? result)
  (status-t dg-txn-t* dg-ids-t* boolean dg-data-list-t**))

(define (dg-extern-data->id txn data result) (status-t dg-txn-t* dg-data-t dg-ids-t**))
(define (dg-id-create txn count result) (status-t dg-txn-t* b32 dg-ids-t**))
(define (dg-exists? txn ids result) (status-t dg-txn-t* dg-ids-t* boolean*))
(define (dg-extern? id) (boolean dg-id-t))
(define (dg-id? id) (boolean dg-id-t))
(define (dg-intern-small? id) (boolean dg-id-t))
(define (dg-identify txn ids result) (status-t dg-txn-t* dg-ids-t* dg-ids-t**))
(define (dg-intern? id) (boolean dg-id-t))
(define (dg-relation? id) (boolean dg-id-t))
(define (dg-index-errors-extern txn result) (status-t dg-txn-t* dg-index-errors-extern-t*))
(define (dg-index-errors-intern txn result) (status-t dg-txn-t* dg-index-errors-intern-t*))
(define (dg-index-errors-relation txn result) (status-t dg-txn-t* dg-index-errors-relation-t*))
(define (dg-index-recreate-extern) status-t)
(define (dg-index-recreate-intern) status-t)
(define (dg-index-recreate-relation) status-t)
(define (dg-init dg-root-argument options) (status-t b8* dg-init-options-t*))
(define (dg-init-options-set-defaults a) (dg-init-options-t dg-init-options-t*))

(define (dg-relation-ensure txn left right label ordinal-generator ordinal-generator-state)
  (status-t dg-txn-t* dg-ids-t* dg-ids-t* dg-ids-t* dg-relation-ordinal-generator-t b0*))

(define (dg-statistics txn result) (status-t dg-txn-t* dg-statistics-t*))
(define (dg-delete txn ids) (status-t dg-txn-t* dg-ids-t*))

(define (dg-relation-delete txn left right label ordinal)
  (status-t dg-txn-t* dg-ids-t* dg-ids-t* dg-ids-t* dg-ordinal-match-data-t*))

(define (dg-status-description a) (b8* status-t))
(define (dg-status-name a) (b8* status-t))
(define (dg-status-group-id->name a) (b8* status-i-t))

(define (dg-relation-select txn left right label ordinal offset result)
  (status-t
    dg-txn-t* dg-ids-t* dg-ids-t* dg-ids-t* dg-ordinal-match-data-t* b32 dg-relation-read-state-t*))

(define (dg-relation-read state count result)
  (status-t dg-relation-read-state-t* b32 dg-relation-records-t**))

(define
  dg-root b8*
  dg-initialised boolean
  dg-mdb-env MDB-env*)

(pre-define (dg-pointer-allocation-set result expression result-temp)
  (set result-temp expression)
  (if result-temp (set result result-temp) (dg-status-set-id-goto dg-status-id-memory)))

(pre-define (dg-ids-add! target source ids-temp)
  (dg-pointer-allocation-set target (dg-ids-add target source) ids-temp))

(pre-define (dg-define-ids name) (define name dg-ids-t* 0))

(pre-define (dg-define-ids-2 name-1 name-2)
  (dg-define-ids name-1)
  (dg-define-ids name-2))

(pre-define (dg-define-ids-3 name-1 name-2 name-3)
  (dg-define-ids-2 name-1 name-2)
  (dg-define-ids name-3))

(pre-define (dg-relation-data->id a) (dg-pointer->id (+ 1 (convert-type a dg-ordinal-t*)) 0))
(pre-define (dg-relation-data->ordinal a) (deref (convert-type a dg-ordinal-t*)))
(pre-define (dg-relation-data-set-id a value) (set (dg-relation-data->id a) value))
(pre-define (dg-relation-data-set-ordinal a value) (set (dg-relation-data->ordinal a) value))

(pre-define (dg-relation-data-set-both a ordinal id)
  (dg-relation-data-set-ordinal ordinal)
  (dg-relation-data-set-id id))

(define (dg-debug-log-ids a) (b0 dg-ids-t*))
(define (dg-debug-log-ids-set a) (b0 imht-set-t))
(define (dg-debug-display-relation-records records) (b0 dg-relation-records-t*))
(define (dg-debug-count-all-btree-entries txn result) (status-t MDB-txn* b32*))
(define (dg-debug-display-btree-counts txn) (status-t MDB-txn*))
(define (dg-debug-display-content-left->right txn) (status-t dg-txn-t*))
(define (dg-debug-display-content-right->left txn) (status-t dg-txn-t*))