diff --git a/geany/smartIndent.lua b/geany/smartIndent.lua
index 93f85ce..01281eb 100644
--- a/geany/smartIndent.lua
+++ b/geany/smartIndent.lua
@@ -22,23 +22,84 @@ function isMember (str, list)
 end
 
 -- Check content
-valid_shebang  = {"#!/bin/sh", "#!/bin/bash"}
-if (geany.text () == nil) then return end
-if not (isMember (geany.lines (1), valid_shebang)) then return end
+if (geany.text () == nil) then geany.status ("smartIndent: File is empty") return end
+valid_shebang  = {
+	bash = {"#!/bin/sh", "#!/bin/bash"},
+	octave = {"#!/usr/bin/octave", "#!/usr/local/bin/octave"},
+	lua = {"#!/usr/bin/lua", "#!/usr/local/bin/lua"}
+}
+
+-- settings
+TAB = "\t"
+rep = 0
+
+increase_words = { 
+	bash = {"for", "while", "if", "function", "{", "case", "until", "select"},
+	octave =  {"for", "while", "if", "function"},
+	lua =  {"for", "while", "if", "function"},
+}
+decrease_words = {
+	bash = {"done", "fi", "}", "esac"},
+	octave = {"end"},
+	lua = {"end"}
+}
+neutral_words  = {
+	bash = {"else", "elif", "then", "do"},
+	octave = {"else", "elseif"},
+	lua = {"else", "elseif"}
+}
+
+-- look for a valid/known shebang in file
+for k,v in pairs(valid_shebang) do
+	if (isMember (geany.lines (1), valid_shebang[k])) then
+		increase_words = increase_words[k]
+		decrease_words = decrease_words[k]
+		neutral_words = neutral_words[k]
+		geany.status ("smartIndent: " .. k)
+		break
+	end
+end
+
+local unknown = function()
+	geany.status ("smartIndent: Unkown shebang")
+	return
+end
+
+--[[
+uh this looks so ugly
+checking if we can follow indent rules by file extension instead of shebang
+--]]
+if (#increase_words == 0) then
+	local filename = geany.filename ()
+	if (filename ~= nil) then		
+		local file_extensions = {".sh", ".m", ".lua"}
+		local file_ext_idx = {"bash", "octave", "lua"}
+		for n = 1,#file_extensions do
+			local from, to = filename:find (file_extensions[n], 1, true) 
+			if (from ~= nil and to ~= nil) then
+				if (#filename == to) then
+					local k = file_ext_idx[n]
+					increase_words = increase_words[k]
+					decrease_words = decrease_words[k]
+					neutral_words = neutral_words[k]
+					geany.status ("smartIndent: " .. k)
+					break
+				end
+			end
+		end
+	else
+		unknown ()
+		return
+	end
+end
+if (#increase_words == 0) then unknown () return end
 
 -- Object of reformatted content
 local this = {}
 setmetatable (this, {__index = table})
 
--- settings
-TAB = "\t"
-rep = 0
-increase_words = {"for", "while", "if", "function", "{", "case", "until", "select"}
-decrease_words = {"done", "fi", "}", "esac"}
-neutral_words  = {"else", "elif", "then", "do"}
 
 local line = ""
-
 -- split content into table by new line
 for n in geany.lines() do
 	line = geany.lines(n):trim()