;;======================================================================
;; Copyright 2017, Matthew Welland.
;; 
;; This file is part of Megatest.
;; 
;;     Megatest is free software: you can redistribute it and/or modify
;;     it under the terms of the GNU General Public License as published by
;;     the Free Software Foundation, either version 3 of the License, or
;;     (at your option) any later version.
;; 
;;     Megatest 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 General Public License for more details.
;; 
;;     You should have received a copy of the GNU General Public License
;;     along with Megatest.  If not, see <http://www.gnu.org/licenses/>.

;;======================================================================

(declare (unit rmtmod))
(declare (uses ulex))

;; (include "ulex/ulex.scm")

(module rmtmod
	*
	
(import scheme chicken data-structures extras)
(import (prefix sqlite3 sqlite3:) posix typed-records srfi-18)
(use tcp6)
(import (prefix ulex ulex:))

(defstruct alldat
  (areapath #f)
  (ulexdat  (ulex:make-udat))
  )

;; create-alldat also sets up our tcp server
;;
(define (create-alldat areapath)
  (let* ((adat (make-alldat))
	 (udat (alldat-ulexdat adat)))
    (alldat-areapath-set! adat areapath)
    (if (not (ulex:start-server-find-port udat (+ 4242 (random 5000))))
	(print "Server NOT started properly"))
    (thread-start! (make-thread
		    (lambda ()
		      (ulex:ulex-handler-loop udat))
		    "Ulex handler loop thread"))
    ;; exit handler needed here
    adat))

(define (send-receive adat cmd rid params)
  (let* ((dbpath (conc (alldat-areapath adat) "/dbs/" (modulo (or rid 0) 1000) ".db")))
    (ulex:remote-call (alldat-ulexdat adat) dbpath 'megatest cmd params)))

;;======================================================================
;; return the handle struct for sending queries to a specific database
;;  - initializes the connection object if this is the first access
;;    - finds the "captain" and asks who to talk to for the given dbfname
;;    - establishes the connection to the current dbowner
;;
#;(define (rmt:connect alldat dbfname dbtype)
  (let* ((ulexdat    (or (alldat-ulexdat alldat)
			 (rmt:setup-ulex alldat))))
    (ulex:connect ulexdat dbfname dbtype)))

;; setup the remote calls
#;(define (rmt:setup-ulex alldat)
  (let* ((udata (ulex:setup))) ;; establish connection to ulex
    (alldat-ulexdat-set! alldat udata)
    ;; register all needed procs
    (ulex:register-handler udata 'ping cmod:get-full-version)  ;; override ping with get-full-version
    (ulex:register-handler udata 'login cmod:get-full-version) ;; force setup of the connection
    (ulex:register-handler udata 'execute api:execute-requests)
    udata))

;; set up a connection to the current owner of the dbfile associated with rid
;; then send the query to that dbfile owner and wait for a response.
;;
#;(define (rmt:send-receive alldat cmd rid params #!key (attemptnum 1)(area-dat #f)) ;; start attemptnum at 1 so the modulo below works as expected
  (let* (;; (alldat   *alldat*)
	 (areapath (alldat-areapath alldat))
	 (dbtype   (if (or (not rid)(< rid 1)) ;; this is the criteria for "main.db"
		       "main" "runs"))
	 (dbfname  (if (equal? dbtype "main")
		       "main.db"
		       (conc rid ".db")))
	 (dbfile   (conc areapath "/.db/" dbfname))
	 (ulexconn (rmt:connect alldat dbfname dbtype))  ;; ulexconn is our new *runremote*, it is a dbowner struct < pdat lastrefresh >
	 (udata    (alldat-ulexdat alldat)))
    	(ulex:remote-request udata ulexconn 'immediate dbfile 'execute rid params)))
    ;; need to call this on the other side 
    ;; (api:execute-requests dbstruct-local (vector (symbol->string cmd) params))))
    
    #;(with-input-from-string
	(ulex:remote-request udata ulexconn 'immediate dbfile 'execute rid (with-output-to-string (lambda ()(serialize params))))
       (lambda ()(deserialize)))
)
