;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; This file is part of "NOVA":  NOVA = search + COCOMO tools
; Copyright, 2008, Tim Menzies tim@menzies.us
;
; NOVA 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.
;
; NOVA 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
; a long with NOVA.  If not, see <http://www.gnu.org/licenses/>.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defsearch isamp ((num-tries 25))
  (let ((max-energy 0))
    (dotimes (i num-tries)
      (if *debug-search* (format t "Try #~a~%" (1+ i)))
      (with-new-path
	(save-state)
	(if *debug-search* (print-state (first-state? path)))
	(loop
	 (cond

	   ;; if the solution is fully constrained, halve max-energy and retry
	   ((= (constrained% (first-state? path)) 1)
	    (setf max-energy (* max-energy 0.5))
	    (return))

	   ;; if max-energy has been exceeded, save the new max-energy and retry
	   ((> (energy? (max-energy? path)) max-energy)
	    (setf max-energy (energy? (max-energy? path)))
	    (return)))

	 ;; randomly move a treatment from open to closed
	 (let ((treatment (?elt (non-singletons? open))))
	   (move-elt treatment open closed))
	 (save-state)
	 (if *debug-search* (print-state (first-state? path))))
	(push path paths)))

    ;; switch to the best path
    (switch-path (find (min-energy? paths) paths :key #'min-energy? :test #'equal))
    (if *debug-search* (terpri))))