(in-package :graph-db)

(defstruct index

skip-list

key-type

order

unique-p

heap

addr)

(alexandria:define-constant string-index 1)

(alexandria:define-constant number-index 2)

(alexandria:define-constant index-ascending 1)

(alexandria:define-constant index-descending 2)

(alexandria:define-constant index-unique 1)

(alexandria:define-constant index-not-unique 2)

(defun make-string-index (heap &key (order :ascending) unique-p

(value-equal 'equal))

(let ((pointer (allocate heap 20))

(skip-list (make-skip-list :heap heap

:key-equal 'string=

:key-comparison (if (eql order :ascending)

'string<

'string>)

:head-key (format nil "~A" (code-char 0))

:tail-key (format nil "~A" (code-char 65535))

:duplicates-allowed-p (null unique-p)

:value-equal value-equal)))

(let ((index (make-index :skip-list skip-list

:key-type :string

:order order

:unique-p unique-p

:heap heap

:addr pointer)))

(set-byte (memory-mmap heap) pointer db-version )

(set-byte (memory-mmap heap) (incf pointer) string-index )

(set-byte (memory-mmap heap) (incf pointer) (if (eql order :ascending)

index-ascending

index-descending ))

(set-byte (memory-mmap heap) (incf pointer) (if unique-p

index-unique

index-not-unique ))

(dolist (addr (list (%sn-addr (%sl-head skip-list))

(%sn-addr (%sl-tail skip-list))))

(dotimes (i 8)

(set-byte (memory-mmap heap)

(incf pointer)

(ldb (byte 8 (* i 8)) addr))))

index)))

(defun make-number-index ()

)

(defun make-custom-index ()

)