\begin{code}
module Main where

import Mandel
import PortablePixmap
import IO --1.3

main = 	getContents >>=  			 	\ userInput	 ->
       	readNum "Enter min x  = " (lines userInput) $	\ minx input 	 ->
       	readNum "Enter min y  = " input $  		\ miny input     ->
       	readNum "Enter max x  = " input $  		\ maxx input     ->
       	readNum "Enter max y  = " input $  		\ maxy input     ->
       	readNum "Screen width = " input $  		\ screenX input  ->
       	readNum "Screen height= " input $  		\ screenY input  ->
       	readNum "Screen depth = " input $  		\ limit _ 	 ->
	putStr (show (mandelset minx miny maxx maxy screenX screenY limit))

readNum::(Num a, Read a) => String -> [String] -> (a->[String]->IO ()) -> IO ()
readNum prompt inputLines succ
   = hPutStr stderr prompt >>
     case inputLines of
       (x:xs) -> case (reads x) of
		   [(y,"")] -> succ y xs
		   _	    -> hPutStr stderr "Error - retype the number\n" >>
			       readNum prompt xs succ
       _ 	-> hPutStr stderr "Early EOF"

{-
Enter min x  = -1.5
Enter min y  = -1.0
Enter max x  = 0.5
Enter max y  = 1.0
-}
\end{code}