-- CallChannel function is called when channel is called
function createExtensionsList(iExtText)
	local list={}
	local pos=0
	local oldPos=0
	local i=0
	local tMax2 = string.len(iExtText)
	while pos<tMax2 do
		if string.sub(iExtText,pos,pos+1)=='\r\n' then
			pos = pos + 2
			list[i+1] = string.sub(iExtText,oldPos,pos-3 )
			oldPos = pos
			i = i + 1
		else
			pos = 1 + pos			
		end

	end
	if oldPos<tMax2 then
		list[i+1] = string.sub(iExtText,oldPos,tMax2)
	end
		
	return list
end

function getExtension(iFileName)
	result=''
	local res=0
	local tMax2 = string.len(iFileName)
	local pos = tMax2
	while pos>0 do
		if string.sub(iFileName,pos,pos)=='.' then
			res = res + 1
			break
		end
		pos = pos-1			
	end
	if res>0 then
		result = string.sub(iFileName,pos+1,tMax2)
	else
		result=iFileName
	end
	return result
end

function extensionFilter(i_fileName)

	local result = 0
	local oExtFound = getExtension(i_fileName)
	
	for i,v in pairs(extList) do 
		if extList[i]==oExtFound then
			result=i
			break
		end
	end
	if result==0 then
--		oExtFound = 'Invalid File'
	end

	return result
end

function searchDirAndFiles(iDirPath)

	local currentValue = channel.GetChild(2)
	local currentDir = channel.GetChild(3)
	local dirOrFiles = channel.GetChild(4)
	local update = channel.GetChild(5)
	local nxItems = channel.GetChild(6)
	local nameOfItem = channel.GetChild(7)
	local result = {{},{}} --(folders,files)
	currentDir:SetText(iDirPath)
	update:CallChannel()


--fileList
	dirOrFiles:SetValue(1) --searchFiles
	local files = nxItems:GetValue()
	currentValue:SetValue(0)
	local i = 0
	while i<files do
		result[1][i+1] = iDirPath..'\\'..nameOfItem:GetText()
		i = 1 + i
		currentValue:SetValue(i)
	end
--createDirList
	local dirList = {}
	dirOrFiles:SetValue(0) --searchDirs
	local folders = nxItems:GetValue()
	currentValue:SetValue(0)
	local j = 0
	while j<folders do
	dirList[j+1] = iDirPath..'\\'..nameOfItem:GetText()
		j = 1 + j
		currentValue:SetValue(j)
	end
--scanChildsFolders
	for k,v in pairs(dirList) do 
		result[2][k] = searchDirAndFiles(dirList[k])
	end

	return result
end

function createFileList(iFsList)

	local result=''

	for i,v in pairs(iFsList[1]) do 
		if extensionFilter(iFsList[1][i])>0 then
			result = result..iFsList[1][i]..'\r\n'
		end

	end
	for i,v in pairs(iFsList[2]) do 

		result = result..createFileList(iFsList[2][i])
	end
	

	return result
end

function CallChannel()
--input data
	local i_extList = channel.GetChild(0):GetText()
	extList = createExtensionsList(i_extList)
	local path = channel.GetChild(1):GetText()

--out data
	local result = channel.GetChild(8)
	if path ~= '' then
	local lFsList = searchDirAndFiles(path)
	local fileList = createFileList(lFsList)
	result:SetText(fileList)
	end

end

-- GetValue function is called when this channels is used as Value
function GetValue()
	return -1
end