// Copyright 2000-2005 the Contributors, as shown in the revision logs.
// Licensed under the Apache Public Source License 2.0 ("the License").
// You may not use this file except in compliance with the License.

package org.ibex.mail;
import org.ibex.crypto.*;
import org.ibex.js.*;
import org.ibex.util.*;
import org.ibex.mail.protocol.*;
import java.util.*;
import java.net.*;
import java.io.*;

// FIXME this should be more forgiving
public class Address extends JSReflection implements Serializable {
    public final String user;
    public final String host;
    public final String description;
    public static Address parse(String s) { try { return s==null?null:new Address(s); } catch (Malformed _) { return null; } }
    public Address(String user, String host, String description) {this.user=user;this.host=host;this.description=description;}
    public Address(String s0) throws Address.Malformed {
        boolean good = false;
        try {
            String s = s0.trim();
            if (s.indexOf('<') == -1) {
                if (s.indexOf(' ') == -1) {
                    description = "";
                } else {
                    description = s.substring(s.indexOf(' ')).trim();
                    s = s.substring(0, s.indexOf(' '));
                }
            } else {
                if (s.indexOf('>') == -1) { throw new Malformed("found open-angle-bracket (<) but not close-angle-bracket (>)"); }
                description = s.substring(0, s.indexOf('<')) + s.substring(s.indexOf('>') + 1);
                s = s.substring(s.indexOf('<') + 1, s.indexOf('>'));
            }
            if (s.trim().length() == 0) {
                user = null;
                host = null;
                good = true;
            } else if (s.indexOf('@') == -1) { throw new Malformed("no @-sign in email address \""+s0+"\"");
            } else {
                user = s.substring(0, s.indexOf('@'));
                host = s.substring(s.indexOf('@')+1);
                good = true;
            }
        } finally {
            if (!good) Log.error(Address.class, "problem parsing: \""+s0+"\"");
        }
    }
    public String toString() { return (user == null && host == null) ? "" : (user + "@" + host); }
    public String coerceToString() { return toString(); }
    public String toString(boolean desc) {
        return desc && description != null && description.length() > 0 ? (description+" <" + toString() + ">") : toString(); }
    public static class Malformed extends Message.Malformed { public Malformed(String s) { super(s); } }

    /** in case of flaky DNS */
    private static HashSet<String> local = new HashSet<String>();
    public boolean isLocal() {
        synchronized(local) {
            if (local.contains(host)) return true;
            InetAddress[] mx = DNSUtil.getMailExchangerIPs(host);
            for(int i=0; i<mx.length; i++) {
                try { if (NetworkInterface.getByInetAddress(mx[i]) != null) {
                    local.add(host);
                    return true;
                } } catch (Exception e) { /* DELIBERATE */ }
            }
        }
        Log.warn(this, "returning false for " + this + ".isLocal()");
        return false;
    }

    public static Address[] list(String spec) {
        if (spec == null) return new Address[] { };
        StringTokenizer st = new StringTokenizer((String)spec, ",");
        Address[] ret = new Address[st.countTokens()];
        for(int i=0; i<ret.length; i++) {
            String s = st.nextToken();
            ret[i] = Address.parse(s);
            if (ret[i] == null) Log.warn(Address.class, "Warning: address " + s + " is unparseable");
        }
        return ret;
    }
}