package org.eclipse.aether.util.repository;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

import java.util.ArrayList;
import java.util.List;

import javax.net.ssl.HostnameVerifier;

import org.eclipse.aether.repository.Authentication;
import org.eclipse.aether.repository.AuthenticationContext;

A utility class to build authentication info for repositories and proxies.
/**
 * A utility class to build authentication info for repositories and proxies.
 */
public final class AuthenticationBuilder
{

    private final List<Authentication> authentications;

    
Creates a new authentication builder.
/**
     * Creates a new authentication builder.
     */
    public AuthenticationBuilder()
    {
        authentications = new ArrayList<>();
    }

    
Builds a new authentication object from the current data of this builder. The state of the builder itself remains
unchanged.
Returns:
The authentication or null if no authentication data was supplied to the builder./**
     * Builds a new authentication object from the current data of this builder. The state of the builder itself remains
     * unchanged.
     * 
     * @return The authentication or {@code null} if no authentication data was supplied to the builder.
     */
    public Authentication build()
    {
        if ( authentications.isEmpty() )
        {
            return null;
        }
        if ( authentications.size() == 1 )
        {
            return authentications.get( 0 );
        }
        return new ChainedAuthentication( authentications );
    }

    
Adds username data to the authentication.
Params:
username – The username, may be null.
Returns:
This builder for chaining, never null./**
     * Adds username data to the authentication.
     * 
     * @param username The username, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addUsername( String username )
    {
        return addString( AuthenticationContext.USERNAME, username );
    }

    
Adds password data to the authentication.
Params:
password – The password, may be null.
Returns:
This builder for chaining, never null./**
     * Adds password data to the authentication.
     * 
     * @param password The password, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addPassword( String password )
    {
        return addSecret( AuthenticationContext.PASSWORD, password );
    }

    
Adds password data to the authentication. The resulting authentication object uses an encrypted copy of the
supplied character data and callers are advised to clear the input array soon after this method returns.
Params:
password – The password, may be null.
Returns:
This builder for chaining, never null./**
     * Adds password data to the authentication. The resulting authentication object uses an encrypted copy of the
     * supplied character data and callers are advised to clear the input array soon after this method returns.
     * 
     * @param password The password, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addPassword( char[] password )
    {
        return addSecret( AuthenticationContext.PASSWORD, password );
    }

    
Adds NTLM data to the authentication.
Params:
workstation – The NTLM workstation name, may be null.
domain – The NTLM domain name, may be null.
Returns:
This builder for chaining, never null./**
     * Adds NTLM data to the authentication.
     * 
     * @param workstation The NTLM workstation name, may be {@code null}.
     * @param domain The NTLM domain name, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addNtlm( String workstation, String domain )
    {
        addString( AuthenticationContext.NTLM_WORKSTATION, workstation );
        return addString( AuthenticationContext.NTLM_DOMAIN, domain );
    }

    
Adds private key data to the authentication.
Params:
pathname – The (absolute) path to the private key file, may be null.
passphrase – The passphrase protecting the private key, may be null.
Returns:
This builder for chaining, never null./**
     * Adds private key data to the authentication.
     * 
     * @param pathname The (absolute) path to the private key file, may be {@code null}.
     * @param passphrase The passphrase protecting the private key, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addPrivateKey( String pathname, String passphrase )
    {
        if ( pathname != null )
        {
            addString( AuthenticationContext.PRIVATE_KEY_PATH, pathname );
            addSecret( AuthenticationContext.PRIVATE_KEY_PASSPHRASE, passphrase );
        }
        return this;
    }

    
Adds private key data to the authentication. The resulting authentication object uses an encrypted copy of the
supplied character data and callers are advised to clear the input array soon after this method returns.
Params:
pathname – The (absolute) path to the private key file, may be null.
passphrase – The passphrase protecting the private key, may be null.
Returns:
This builder for chaining, never null./**
     * Adds private key data to the authentication. The resulting authentication object uses an encrypted copy of the
     * supplied character data and callers are advised to clear the input array soon after this method returns.
     * 
     * @param pathname The (absolute) path to the private key file, may be {@code null}.
     * @param passphrase The passphrase protecting the private key, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addPrivateKey( String pathname, char[] passphrase )
    {
        if ( pathname != null )
        {
            addString( AuthenticationContext.PRIVATE_KEY_PATH, pathname );
            addSecret( AuthenticationContext.PRIVATE_KEY_PASSPHRASE, passphrase );
        }
        return this;
    }

    
Adds a hostname verifier for SSL. Note: This method assumes that all possible instances of the verifier's runtime type exhibit the exact same behavior, i.e. the behavior of the verifier depends solely on the runtime type and not on any configuration. For verifiers that do not fit this assumption, use addCustom(Authentication) with a suitable implementation instead. 
Params:
verifier – The hostname verifier, may be null.
Returns:
This builder for chaining, never null./**
     * Adds a hostname verifier for SSL. <strong>Note:</strong> This method assumes that all possible instances of the
     * verifier's runtime type exhibit the exact same behavior, i.e. the behavior of the verifier depends solely on the
     * runtime type and not on any configuration. For verifiers that do not fit this assumption, use
     * {@link #addCustom(Authentication)} with a suitable implementation instead.
     * 
     * @param verifier The hostname verifier, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addHostnameVerifier( HostnameVerifier verifier )
    {
        if ( verifier != null )
        {
            authentications.add( new ComponentAuthentication( AuthenticationContext.SSL_HOSTNAME_VERIFIER, verifier ) );
        }
        return this;
    }

    
Adds custom string data to the authentication. Note: If the string data is confidential, use addSecret(String, char[]) instead. 
Params:
key – The key for the authentication data, must not be null.
value – The value for the authentication data, may be null.
Returns:
This builder for chaining, never null./**
     * Adds custom string data to the authentication. <em>Note:</em> If the string data is confidential, use
     * {@link #addSecret(String, char[])} instead.
     * 
     * @param key The key for the authentication data, must not be {@code null}.
     * @param value The value for the authentication data, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addString( String key, String value )
    {
        if ( value != null )
        {
            authentications.add( new StringAuthentication( key, value ) );
        }
        return this;
    }

    
Adds sensitive custom string data to the authentication.
Params:
key – The key for the authentication data, must not be null.
value – The value for the authentication data, may be null.
Returns:
This builder for chaining, never null./**
     * Adds sensitive custom string data to the authentication.
     * 
     * @param key The key for the authentication data, must not be {@code null}.
     * @param value The value for the authentication data, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addSecret( String key, String value )
    {
        if ( value != null )
        {
            authentications.add( new SecretAuthentication( key, value ) );
        }
        return this;
    }

    
Adds sensitive custom string data to the authentication. The resulting authentication object uses an encrypted
copy of the supplied character data and callers are advised to clear the input array soon after this method
returns.
Params:
key – The key for the authentication data, must not be null.
value – The value for the authentication data, may be null.
Returns:
This builder for chaining, never null./**
     * Adds sensitive custom string data to the authentication. The resulting authentication object uses an encrypted
     * copy of the supplied character data and callers are advised to clear the input array soon after this method
     * returns.
     * 
     * @param key The key for the authentication data, must not be {@code null}.
     * @param value The value for the authentication data, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addSecret( String key, char[] value )
    {
        if ( value != null )
        {
            authentications.add( new SecretAuthentication( key, value ) );
        }
        return this;
    }

    
Adds custom authentication data to the authentication.
Params:
authentication – The authentication to add, may be null.
Returns:
This builder for chaining, never null./**
     * Adds custom authentication data to the authentication.
     * 
     * @param authentication The authentication to add, may be {@code null}.
     * @return This builder for chaining, never {@code null}.
     */
    public AuthenticationBuilder addCustom( Authentication authentication )
    {
        if ( authentication != null )
        {
            authentications.add( authentication );
        }
        return this;
    }

}