open Ostap

let parse infile =
  let s = Util.read infile in
  Util.parse
    (object
       inherit Matcher.t s
       inherit Util.Lexers.decimal s
       inherit Util.Lexers.string s
       inherit Util.Lexers.char   s
       inherit Util.Lexers.ident ["skip";
                                  "if"; "then"; "else"; "elif"; "fi";
                                  "while"; "do"; "od";
                                  "repeat"; "until";
                                  "for";
                                  "fun"; "local"; "return";
                                  "length";
                                  "case"; "of"; "esac"; "when"] s
       inherit Util.Lexers.skip [
	 Matcher.Skip.whitespaces " \t\n";
	 Matcher.Skip.lineComment "--";
	 Matcher.Skip.nestedComment "(*" "*)"
       ] s
     end
    )
    (ostap (!(Language.parse) -EOF))

let main =
  try
    let interpret  = Sys.argv.(1) = "-i"  in
    let stack      = Sys.argv.(1) = "-s"  in
    let to_compile = not (interpret || stack) in
    let infile     = Sys.argv.(if not to_compile then 2 else 1) in
    match parse infile with
    | `Ok prog ->
      if to_compile
      then            
        let basename = Filename.chop_suffix infile ".expr" in
        ignore @@ X86.build prog basename        
      else 
	let rec read acc =
	  try
	    let r = read_int () in
	    Printf.printf "> ";
	    read (acc @ [r]) 
          with End_of_file -> acc
	in
	let input = read [] in	
	let output = 
	  if interpret 
	  then Language.eval prog input 
	  else SM.run (SM.compile prog) input
	in
	List.iter (fun i -> Printf.printf "%d\n" i) output
    | `Fail er -> Printf.eprintf "Syntax error: %s\n" er
  with Invalid_argument _ ->
    Printf.printf "Usage: rc [-i | -s] <input file.expr>\n"