/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.net;

import android.net.ProxyProperties;
import android.os.Parcelable;
import android.os.Parcel;
import android.util.Log;

import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;

/**
 * Describes the properties of a network link.
 *
 * A link represents a connection to a network.
 * It may have multiple addresses and multiple gateways,
 * multiple dns servers but only one http proxy.
 *
 * Because it's a single network, the dns's
 * are interchangeable and don't need associating with
 * particular addresses.  The gateways similarly don't
 * need associating with particular addresses.
 *
 * A dual stack interface works fine in this model:
 * each address has it's own prefix length to describe
 * the local network.  The dns servers all return
 * both v4 addresses and v6 addresses regardless of the
 * address family of the server itself (rfc4213) and we
 * don't care which is used.  The gateways will be
 * selected based on the destination address and the
 * source address has no relavence.
 * @hide
 */
public class LinkProperties implements Parcelable {

    String mIfaceName;
    private Collection<LinkAddress> mLinkAddresses;
    private Collection<InetAddress> mDnses;
    private Collection<InetAddress> mGateways;
    private ProxyProperties mHttpProxy;

    public LinkProperties() {
        clear();
    }

    // copy constructor instead of clone
    public LinkProperties(LinkProperties source) {
        if (source != null) {
            mIfaceName = source.getInterfaceName();
            mLinkAddresses = source.getLinkAddresses();
            mDnses = source.getDnses();
            mGateways = source.getGateways();
            mHttpProxy = new ProxyProperties(source.getHttpProxy());
        }
    }

    public void setInterfaceName(String iface) {
        mIfaceName = iface;
    }

    public String getInterfaceName() {
        return mIfaceName;
    }

    public Collection<InetAddress> getAddresses() {
        Collection<InetAddress> addresses = new ArrayList<InetAddress>();
        for (LinkAddress linkAddress : mLinkAddresses) {
            addresses.add(linkAddress.getAddress());
        }
        return Collections.unmodifiableCollection(addresses);
    }

    public void addLinkAddress(LinkAddress address) {
        mLinkAddresses.add(address);
    }

    public Collection<LinkAddress> getLinkAddresses() {
        return Collections.unmodifiableCollection(mLinkAddresses);
    }

    public void addDns(InetAddress dns) {
        mDnses.add(dns);
    }

    public Collection<InetAddress> getDnses() {
        return Collections.unmodifiableCollection(mDnses);
    }

    public void addGateway(InetAddress gateway) {
        mGateways.add(gateway);
    }
    public Collection<InetAddress> getGateways() {
        return Collections.unmodifiableCollection(mGateways);
    }

    public void setHttpProxy(ProxyProperties proxy) {
        mHttpProxy = proxy;
    }
    public ProxyProperties getHttpProxy() {
        return mHttpProxy;
    }

    public void clear() {
        mIfaceName = null;
        mLinkAddresses = new ArrayList<LinkAddress>();
        mDnses = new ArrayList<InetAddress>();
        mGateways = new ArrayList<InetAddress>();
        mHttpProxy = null;
    }

    /**
     * Implement the Parcelable interface
     * @hide
     */
    public int describeContents() {
        return 0;
    }

    @Override
    public String toString() {
        String ifaceName = (mIfaceName == null ? "" : "InterfaceName: " + mIfaceName + " ");

        String linkAddresses = "LinkAddresses: [";
        for (LinkAddress addr : mLinkAddresses) linkAddresses += addr.toString();
        linkAddresses += "] ";

        String dns = "DnsAddresses: [";
        for (InetAddress addr : mDnses) dns += addr.getHostAddress() + ",";
        dns += "] ";

        String gateways = "Gateways: [";
        for (InetAddress gw : mGateways) gateways += gw.getHostAddress() + ",";
        gateways += "] ";
        String proxy = (mHttpProxy == null ? "" : "HttpProxy: " + mHttpProxy.toString() + " ");

        return ifaceName + linkAddresses + gateways + dns + proxy;
    }

    /**
     * Implement the Parcelable interface.
     * @hide
     */
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(getInterfaceName());
        dest.writeInt(mLinkAddresses.size());
        for(LinkAddress linkAddress : mLinkAddresses) {
            dest.writeParcelable(linkAddress, flags);
        }

        dest.writeInt(mDnses.size());
        for(InetAddress d : mDnses) {
            dest.writeByteArray(d.getAddress());
        }

        dest.writeInt(mGateways.size());
        for(InetAddress gw : mGateways) {
            dest.writeByteArray(gw.getAddress());
        }

        if (mHttpProxy != null) {
            dest.writeByte((byte)1);
            dest.writeParcelable(mHttpProxy, flags);
        } else {
            dest.writeByte((byte)0);
        }
    }

    /**
     * Implement the Parcelable interface.
     * @hide
     */
    public static final Creator<LinkProperties> CREATOR =
        new Creator<LinkProperties>() {
            public LinkProperties createFromParcel(Parcel in) {
                LinkProperties netProp = new LinkProperties();
                String iface = in.readString();
                if (iface != null) {
                    try {
                        netProp.setInterfaceName(iface);
                    } catch (Exception e) {
                        return null;
                    }
                }
                int addressCount = in.readInt();
                for (int i=0; i<addressCount; i++) {
                    netProp.addLinkAddress((LinkAddress)in.readParcelable(null));
                }
                addressCount = in.readInt();
                for (int i=0; i<addressCount; i++) {
                    try {
                        netProp.addDns(InetAddress.getByAddress(in.createByteArray()));
                    } catch (UnknownHostException e) { }
                }
                addressCount = in.readInt();
                for (int i=0; i<addressCount; i++) {
                    try {
                        netProp.addGateway(InetAddress.getByAddress(in.createByteArray()));
                    } catch (UnknownHostException e) { }
                }
                if (in.readByte() == 1) {
                    netProp.setHttpProxy((ProxyProperties)in.readParcelable(null));
                }
                return netProp;
            }

            public LinkProperties[] newArray(int size) {
                return new LinkProperties[size];
            }
        };
}