-- helper to pop-up an error dialog
local function showError(text)
    octane.gui.showDialog
    {
        type  = octane.gui.dialogType.BUTTON_DIALOG,
        icon  = octane.gui.dialogIcon.WARNING,
        title = "Daylight Animation Error",
        text  = text,
    }
end



function updateFileData(objFile)
    local f = io.open(objFile, "r")
    local fileData = f:read("*all")
    f:close()
    fileData = fileData:gsub("g (%w+)", "usemtl %1")
	
	f = io.open(objFile, "w")
	f:write(fileData)
	f:close()
	--print (fileData)
	
end

local function reloadMeshGroupsAsMaterials()
	-- get the selected mesh
	local selected = octane.project.getSelection()[1]
	if not selected or selected.type ~= octane.NT_GEO_MESH then
		showError("no mesh selected")
		return nil
	end

	-- get the file path for the mesh
	local objFileName = octane.node.getAttribute( selected , 29 ) 

	--print (objFileName )
	updateFileData(objFileName)

	--reload mesh
	octane.node.setAttribute(selected, 94, true, true)
end

reloadMeshGroupsAsMaterials()