module snug

import StdEnv
import StdMaybe

import System.CommandLine

import Snug.Parse

Start w
	# ([prog:args],w) = getCommandLine w
	| length args <> 1 = abort ("Usage: " +++ prog +++ " INPUT\n")
	# input = hd args
	# (mbInput,w) = readFile input w
	  input = fromJust mbInput
	| isNone mbInput = abort "Failed to read input\n"
	| otherwise = parseSnug input

readFile :: !String !*World -> (!?[Char], !*World)
readFile path w
	# (ok,f,w) = fopen path FReadData w
	| not ok = (?None, w)
	# (contents,f) = read [] f
	# (_,w) = fclose f w
	= (?Just contents, w)
where
	read :: ![Char] !*File -> (![Char], !*File)
	read acc f
		# (ok,c,f) = freadc f
		| not ok = (reverse acc, f)
		| otherwise = read [c:acc] f