Megatest

;;  R E C O R D S
;;======================================================================

;; each db entry is a pair ( db . dbfilepath )
;; I propose this record evolves into the area record
;;
(defstruct dbr:dbstruct 
  (tmpdb       #f)
  (dbstack     #f) ;; stack for tmp db handles, do not initialize with a stack
  (mtdb        #f)
  (refndb      #f)
  (homehost    #f) ;; not used yet
  (on-homehost #f) ;; not used yet
  (read-only   #f)
  )                ;; goal is to converge on one struct for an area but for now it is too confusing

;;     (dbr:dbstruct-olddb-set!  dbstruct olddb)
;;     ;;; (mutex-unlock! *rundb-mutex*) ;;; why did we need a mutex on opening db's?
;;     (db:sync-tables db:sync-tests-only *megatest-db* db)
;;     db))

;; This routine creates the db if not already present. It is only called if the db is not already opened
;;
(define (db:open-db dbstruct #!key (areapath #f)) ;; TODO: actually use areapath
  (let ((tmpdb-stack (dbr:dbstruct-dbstack dbstruct))) ;; RA => Returns the first reference in dbstruct
    (if (stack? tmpdb-stack)
	(db:get-db tmpdb-stack) ;; get previously opened db (will create new db handle if all in the stack are already used
        (let* ((dbpath       (db:dbfile-path)) ;;  0))
               (dbexists     (file-exists? dbpath))
	       (dbfexists    (file-exists? (conc dbpath "/megatest.db")))
               (tmpdb        (db:open-megatest-db path: dbpath)) ;; lock-create-open dbpath db:initialize-main-db))
               (mtdb         (db:open-megatest-db))
               (refndb       (db:open-megatest-db path: dbpath name: "megatest_ref.db"))
               (write-access (file-write-access? dbpath)))
          (if (and dbexists (not write-access))
              (begin (set! *db-write-access* #f)
                     (dbr:dbstruct-readonly-set! dbstruct #t)))

          (dbr:dbstruct-mtdb-set!   dbstruct mtdb)
          (dbr:dbstruct-tmpdb-set!  dbstruct tmpdb)
          (dbr:dbstruct-dbstack-set! dbstruct (make-stack)) ;; BB: why a stack?  Why would the number of db's be indeterminate?  Is this a legacy of 1.db 2.db .. ?
          (stack-push! (dbr:dbstruct-dbstack dbstruct) tmpdb) ;; olddb is already a (cons db path)
          (dbr:dbstruct-refndb-set! dbstruct refndb)
          ;;	    (mutex-unlock! *rundb-mutex*)
          (if (and (not dbfexists)
                   write-access) ;; *db-write-access*) ;; did not have a prior db and do have write access
	      (begin
		(debug:print 0 *default-log-port* "filling db " (db:dbdat-get-path tmpdb) " with data from " (db:dbdat-get-path mtdb))
		(db:sync-tables (db:sync-all-tables-list dbstruct) #f mtdb refndb tmpdb))
	      (debug:print 0 *default-log-port* " db, " (db:dbdat-get-path tmpdb) " already exists, not propogating data from " (db:dbdat-get-path mtdb)))
	  ;; (db:multi-db-sync dbstruct 'old2new))  ;; migrate data from megatest.db automatically
          tmpdb))))

;; Make the dbstruct, setup up auxillary db's and call for main db at least once
;;
;; called in http-transport and replicated in rmt.scm for *local* access. 
;;
(define (db:setup #!key (areapath #f))
  (or *dbstruct-db* ;; TODO: when multiple areas are supported, this optimization will be a hazard
      (if (common:on-homehost?)
	  (let* ((dbstruct (make-dbr:dbstruct)))
	    (db:open-db dbstruct areapath: areapath)
	    (set! *dbstruct-db* dbstruct)
	    dbstruct)
	  (begin
	    (debug:print 0 *default-log-port* "ERROR: attempt to open database when not on homehost. Exiting. Homehost: " (common:get-homehost))