;;read original model input file

;;n choose i = n!/(n-i)!*i!
;;
;; for i= 3-> n_images 
;;	for j= 1-> (n-choose-i / n) do
;;		pick i random files and run model 
;;		store output in folder k with metadata & k+=1
;;
;;	eventually evaluate all output
;;
function N_choose_m, N, m
	top = factorial(N)
	bottom = factorial(N-m) * factorial(m)
	return, float(top)/bottom
end

function pick_m_of_N, m, N, seed

	list = indgen(N)
	results = intarr(m)
	for i=0, m-1 do begin
		index = round(randomu(seed) *(N-1-i))
;		print, list
;		print, index
		results(i) = list(index)
		if index eq 0 then begin 
			list = list(1:n_elements(list)-1)
		endif else if index eq n_elements(list)-1 then begin
			list = list(0:index-1)
		endif else begin
			list= [list(0:index-1), list(index+1:n_elements(list)-1)]
		endelse
	endfor
	return, results
end


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;	Parses the input file into a structure
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
function readInputFile, inputfile
	if not file_test(inputfile) then return, {n_images:-1}

	openr, un, /get, inputfile

	n_images=0
	readf, un, n_images

;;Read all of the image file names
	filenames=strarr(n_images)	
	for i=0, n_images-1 do begin
		tmp=''
		readf, un, tmp
		filenames(i) = tmp
	endfor
	
;;Read all of the image dates
	dates=intarr(3,n_images)	
	for i=0, n_images-1 do begin
		j=0
		tmp=''
		readf, un, tmp
		tmp=strsplit(tmp, /extract)
		if n_elements(tmp) lt 3 then return, {n_images:-2}
		for k=0, 2 do begin
			reads, tmp(k),j
			dates(k,i) = j
		endfor
	endfor

;;read in the remaining file names
	sandfile=''
	readf, un, sandfile
	
	rangefile=''
	readf, un, rangefile
	
	centdir=''
	readf, un, centdir
	
	winddir=''
	readf, un, winddir
	
	c3c4file=''
	readf, un, c3c4file

	close, un
	free_lun, un
;;return the result in a simple structure
	return, {n_images:n_images,filenames:filenames, dates:dates, $
		sandfile:sandfile, rangefile:rangefile, centdir:centdir,$
		winddir:winddir, c3c4file:c3c4file}
end

pro writeNewInput, info, newFilename
	openw, oun, /get, newFilename
	printf, oun, info.n_images
	for i=0, info.n_images-1 do begin
		printf, oun, info.filenames(i)
	endfor
	printf, oun, info.dates(*,0:info.n_images-1)
	printf, oun, info.sandfile
	printf, oun, info.rangefile
	printf, oun, info.centdir
	printf, oun, info.winddir
	printf, oun, info.c3c4file
	close, oun
	free_lun, oun
end

pro N_Image_Test
  
  totalInfo = readInputFile('ModelInput')

  n_images = totalInfo.n_images
  seed = 2754

  for Cur_N = 7, n_images do begin
     sectionResults = strcompress(Cur_N, /remove_all)+'of'+strcompress(n_images, /remove_all)
;		file_mkdir, sectionResults
     n_tries = min([10, round(N_choose_m(n_images, Cur_N) / float(n_images))])
     IF (Cur_N EQ n_images-1) OR (Cur_N EQ n_images-2) THEN n_tries=10
     print, 'n_tries ', n_tries, cur_N, n_images
     for i=0, n_tries-1 do begin
        curResults = 'Try-'+strcompress(i,/remove_all)
;			cd, sectionResults
;			file_mkdir, curResults
;			up
        
        index = pick_m_of_N(cur_N, n_images, seed)
        seed = seed+i
        
        files = totalInfo.filenames(index)
        dates = totalInfo.dates(*,index)
        
        print, dates
        newInfo = totalInfo
        newInfo.dates = dates
        newInfo.filenames=files
        newInfo.n_images = Cur_N
        
        modelinput = 'tmpModelInput'+strcompress(i+(cur_N*100l), /remove_all)
        writeNewInput, newInfo, modelinput
        
        print, files
        print, modelinput
        print, 'starting model...'
        
        HighPlainsDuneModel, modelinput, /nocent, /daycent, $ 
                             logname=strcompress(i+(cur_N*100l), /remove_all), $
                             fullMask='fullMasktmp', windFile='windMap.out'
;; these can't be used because every year has a SLIGHTLY different shape! should I fix that?
;				fullMask='fullMasktmp', $
;				windFile='windMap.out', $
        spawn, 'rm SandTransport*'
        spawn, 'rm resizedSand*'
        spawn, 'rm NDVIvsCentMeta*.out'
        spawn, 'mv *.ps realnewpsfiles/'
        spawn, 'mv NDVI*.out* realnewoutfiles/'
        spawn, 'mv OUTPUT* realnewlogfiles/'
        

     endfor
  endfor
end