/**
 * AmziPreds.java
 *
 * A template for a Java class that implements a number
 * of non-application-specific extended Prolog predicates.
 * It is used with the Pets example, and includes one
 * simple extended predicate that prompts a user for
 * an answer.
 */

import amzi.ls.*;
import java.io.*;

class AmziPreds
{
	private LogicServer ls;
	private BufferedReader din;

	AmziPreds(LogicServer tls) throws LSException
	{
		// Initialize a buffered reader for the input prompts
		din = new BufferedReader(new InputStreamReader(System.in));

		// Save the Logic Server object reference, and register
		// the extended predicates.
		ls = tls;
		ls.AddPred("prompt", 2, "AmziPreds", "prompt", this);
	}

	public boolean prompt()
	{
		String answer;
		boolean tf;

		try
		{
			// Prompt with the first parameter
			System.out.println(ls.GetStrParm(1));

			// Use the buffered reader to get an answer
			// for the second, unify it and return true/false
			// depending on the result of the unification.
			return ls.UnifyStrParm(2, din.readLine());
		}
		catch (LSException e)
		{
			System.out.println(e.GetMsg());
			return false;
		}
		catch (IOException e)
		{
			System.out.println(e.getMessage());
			return false;
		}
	}
}