/*
 * $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/HttpClient.java,v 1.96 2004/06/14 21:25:38 olegk Exp $
 * $Revision: 1.96 $
 * $Date: 2004/06/14 21:25:38 $
 *
 * ====================================================================
 *
 *  Copyright 1999-2004 The Apache Software Foundation
 *
 *  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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.commons.httpclient;

import java.io.IOException;
import java.security.Provider;
import java.security.Security;

import org.apache.commons.httpclient.params.HttpClientParams;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * <p>
 * An HTTP "user-agent", containing an {@link HttpState HTTP state} and
 * one or more {@link HttpConnection HTTP connections}, to which
 * {@link HttpMethod HTTP methods} can be applied.
 * </p>
 * @author <a href="mailto:remm@apache.org">Remy Maucherat</a>
 * @author <a href="mailto:rwaldhoff@apache.org">Rodney Waldhoff</a>
 * @author Sean C. Sullivan
 * @author <a href="mailto:dion@apache.org">dIon Gillard</a>
 * @author Ortwin Gl?ck
 * @author <a href="mailto:becke@u.washington.edu">Michael Becke</a>
 * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
 * @author Sam Maloney
 * @author Laura Werner
 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
 * 
 * @version $Revision: 1.96 $ $Date: 2004/06/14 21:25:38 $
 */
public class HttpClient {


    // -------------------------------------------------------------- Constants

    /** Log object for this class. */
    private static final Log LOG = LogFactory.getLog(HttpClient.class);

    static {
        
        if (LOG.isDebugEnabled()) {
            try {
                LOG.debug("Java version: " + System.getProperty("java.version"));
                LOG.debug("Java vendor: " + System.getProperty("java.vendor"));
                LOG.debug("Java class path: " + System.getProperty("java.class.path"));
                LOG.debug("Operating system name: " + System.getProperty("os.name"));
                LOG.debug("Operating system architecture: " + System.getProperty("os.arch"));
                LOG.debug("Operating system version: " + System.getProperty("os.version"));

                Provider[] providers = Security.getProviders();
                for (int i = 0; i < providers.length; i++) {
                    Provider provider = providers[i];
                    LOG.debug(provider.getName() + " " + provider.getVersion()
                       + ": " + provider.getInfo());   
                }
            } catch (SecurityException ignore) {
            }
        }
    }
    // ----------------------------------------------------------- Constructors

    /**
     * Creates an instance of HttpClient using default {@link HttpClientParams parameter set}.
     * 
     * @see HttpClientParams
     */
    public HttpClient() {
        this(new HttpClientParams());
    }

    /**
     * Creates an instance of HttpClient using the given 
     * {@link HttpClientParams parameter set}.
     * 
     * @param params The {@link HttpClientParams parameters} to use.
     * 
     * @see HttpClientParams
     * 
     * @since 3.0
     */
    public HttpClient(HttpClientParams params) {
        super();
        if (params == null) {
            throw new IllegalArgumentException("Params may not be null");  
        }
        this.params = params;
        this.httpConnectionManager = null;
        Class clazz = params.getConnectionManagerClass();
        if (clazz != null) {
            try {
                this.httpConnectionManager = (HttpConnectionManager) clazz.newInstance();
            } catch (Exception e) {
                LOG.warn("Error instantiating connection manager class, defaulting to"
                    + " SimpleHttpConnectionManager", 
                    e);
            }
        }
        if (this.httpConnectionManager == null) {
            this.httpConnectionManager = new SimpleHttpConnectionManager();
        }
        if (this.httpConnectionManager != null) {
            this.httpConnectionManager.getParams().setDefaults(this.params);
        }
    }

    /**
     * Creates an instance of HttpClient with a user specified 
     * {@link HttpClientParams parameter set} and 
     * {@link HttpConnectionManager HTTP connection manager}.
     * 
     * @param params The {@link HttpClientParams parameters} to use.
     * @param httpConnectionManager The {@link HttpConnectionManager connection manager}
     * to use.
     * 
     * @since 3.0
     */
    public HttpClient(HttpClientParams params, HttpConnectionManager httpConnectionManager) {
        super();
        if (httpConnectionManager == null) {
            throw new IllegalArgumentException("httpConnectionManager cannot be null");  
        }
        if (params == null) {
            throw new IllegalArgumentException("Params may not be null");  
        }
        this.params = params; 
        this.httpConnectionManager = httpConnectionManager;
        if (this.httpConnectionManager != null) {
            this.httpConnectionManager.getParams().setDefaults(this.params);
        }
    }
    
    /**
     * Creates an instance of HttpClient with a user specified 
     * {@link HttpConnectionManager HTTP connection manager}.
     * 
     * @param httpConnectionManager The {@link HttpConnectionManager connection manager}
     * to use.
     * 
     * @since 2.0
     */
    public HttpClient(HttpConnectionManager httpConnectionManager) {
        this(new HttpClientParams(), httpConnectionManager);
    }
    
    // ----------------------------------------------------- Instance Variables

    /** 
     * The {@link HttpConnectionManager connection manager} being used to manage
     * connections for this HttpClient
     */
    private HttpConnectionManager httpConnectionManager;

    /**
     * The {@link HttpState HTTP state} associated with this HttpClient.
     */
    private HttpState state = new HttpState();
    
    /**
     * The {@link HttpClientParams collection of parameters} associated with this HttpClient.
     */
    private HttpClientParams params = null; 

    /** 
     * The {@link HostConfiguration host configuration} associated with
     * the HttpClient
     */
    private HostConfiguration hostConfiguration = new HostConfiguration();
    
    // ------------------------------------------------------------- Properties

    /**
     * Returns {@link HttpState HTTP state} associated with the HttpClient.
     *
     * @see #setState(HttpState)
     * @return the shared client state
     */
    public synchronized HttpState getState() {
        return state;
    }

    /**
     * Assigns {@link HttpState HTTP state} for the HttpClient.
     *
     * @see #getState()
     * @param state the new {@link HttpState HTTP state} for the client
     */
    public synchronized void setState(HttpState state) {
        this.state = state;
    }

    /**
     * Defines how strictly the method follows the HTTP protocol specification  
     * (see RFC 2616 and other relevant RFCs). 
     * 
     * In the strict mode the method precisely
     * implements the requirements of the specification, whereas in non-strict mode 
     * it attempts to mimic the exact behaviour of commonly used HTTP agents, 
     * which many HTTP servers expect.
     * 
     * @param strictMode <tt>true</tt> for strict mode, <tt>false</tt> otherwise
     *
     * @see #isStrictMode()
     *
     * @deprecated Use {@link HttpClientParams#setParameter(String, Object)}
     * to exercise a more granular control over HTTP protocol strictness.
     */
    public synchronized void setStrictMode(boolean strictMode) {
        if (strictMode) {
            this.params.makeStrict();
        } else {
            this.params.makeLenient();
        }
    }

    /**
     * Returns the value of the strict mode flag.
     * 
     * @return <tt>true</tt> if strict mode is enabled, <tt>false</tt> otherwise
     *
     * @see #setStrictMode(boolean)
     *
     * @deprecated Use 
     * {@link org.apache.commons.httpclient.params.HttpClientParams#getParameter(String)} 
     * to exercise a more granular control over HTTP protocol strictness.
     */
    public synchronized boolean isStrictMode() {
        return false;
    }

    /**
     * Sets the socket timeout (<tt>SO_TIMEOUT</tt>) in milliseconds which is the 
     * timeout for waiting for data. A timeout value of zero is interpreted as an 
     * infinite timeout.
     *
     * @param newTimeoutInMilliseconds Timeout in milliseconds
     * 
     * @deprecated Use 
     * {@link org.apache.commons.httpclient.params.HttpConnectionManagerParams#setSoTimeout(int)},
     * {@link HttpConnectionManager#getParams()}.
     *
     */
    public synchronized void setTimeout(int newTimeoutInMilliseconds) {
        this.params.setSoTimeout(newTimeoutInMilliseconds);
    }

    /**
     * Sets the timeout in milliseconds used when retrieving an 
     * {@link HttpConnection HTTP connection} from the
     * {@link HttpConnectionManager HTTP connection manager}.
     * 
     * @param timeout the timeout in milliseconds
     * 
     * @see HttpConnectionManager#getConnection(HostConfiguration, long)
     * 
     * @deprecated Use 
     * {@link org.apache.commons.httpclient.params.HttpClientParams#setConnectionManagerTimeout(long)},
     * {@link HttpClient#getParams()}
     */
    public synchronized void setHttpConnectionFactoryTimeout(long timeout) {
        this.params.setConnectionManagerTimeout(timeout);
    }

    /**
     * Sets the timeout until a connection is etablished. A value of zero 
     * means the timeout is not used. The default value is zero.
     * 
     * @see HttpConnection#setConnectionTimeout(int)
     * @param newTimeoutInMilliseconds Timeout in milliseconds.
     * 
     * @deprecated Use 
     * {@link org.apache.commons.httpclient.params.HttpConnectionManagerParams#setConnectionTimeout(int)},
     * {@link HttpConnectionManager#getParams()}.
     */
    public synchronized void setConnectionTimeout(int newTimeoutInMilliseconds) {
       this.httpConnectionManager.getParams().setConnectionTimeout(newTimeoutInMilliseconds);
    }

    // --------------------------------------------------------- Public Methods

   /**
     * Executes the given {@link HttpMethod HTTP method}.
     *
     * @param method the {@link HttpMethod HTTP method} to execute.
     * @return the method's response code
     *
     * @throws IOException If an I/O (transport) error occurs. Some transport exceptions
     *                     can be recovered from.      
     * @throws HttpException  If a protocol exception occurs. Usually protocol exceptions 
     *                    cannot be recovered from.
     */
    public int executeMethod(HttpMethod method)
        throws IOException, HttpException  {
            
        LOG.trace("enter HttpClient.executeMethod(HttpMethod)");
        // execute this method and use its host configuration, if it has one
        return executeMethod(
            method.getHostConfiguration() != null 
            ? method.getHostConfiguration()
            : getHostConfiguration(), 
            method,
            null
        );
        
    }

    /**
    * Executes the given {@link HttpMethod HTTP method} using custom 
    * {@link HostConfiguration host configuration}.
    *
    * @param hostConfiguration The {@link HostConfiguration host configuration} to use.
    * @param method the {@link HttpMethod HTTP method} to execute.
    * @return the method's response code
    *
    * @throws IOException If an I/O (transport) error occurs. Some transport exceptions
    *                     can be recovered from.
    * @throws HttpException  If a protocol exception occurs. Usually protocol exceptions 
    *                    cannot be recovered from.
    * @since 2.0
    */
    public int executeMethod(HostConfiguration hostConfiguration, HttpMethod method)
        throws IOException, HttpException {
    
        LOG.trace("enter HttpClient.executeMethod(HostConfiguration,HttpMethod)");
    
        return executeMethod(hostConfiguration, method, null); 
    }
    

    
    /**
     * Executes the given {@link HttpMethod HTTP method} using the given custom 
     * {@link HostConfiguration host configuration} with the given custom 
     * {@link HttpState HTTP state}.
     *
     * @param hostConfiguration The {@link HostConfiguration host configuration} to use.
     * @param method the {@link HttpMethod HTTP method} to execute.
     * @param state the {@link HttpState HTTP state} to use when executing the method.
     * If <code>null</code>, the state returned by {@link #getState} will be used instead.
     *
     * @return the method's response code
     *
     * @throws IOException If an I/O (transport) error occurs. Some transport exceptions
     *                     can be recovered from.
     * @throws HttpException  If a protocol exception occurs. Usually protocol exceptions 
     *                    cannot be recovered from.
     * @since 2.0
     */
    public int executeMethod(HostConfiguration hostConfiguration, 
        HttpMethod method, HttpState state)
        throws IOException, HttpException  {
            
        LOG.trace("enter HttpClient.executeMethod(HostConfiguration,HttpMethod,HttpState)");

        if (method == null) {
            throw new IllegalArgumentException("HttpMethod parameter may not be null");
        }

        if (hostConfiguration == null) {
            hostConfiguration = (
                method.getHostConfiguration() != null 
                ? method.getHostConfiguration()
                : getHostConfiguration()
            );
        }

        HostConfiguration defaultHostConfiguration = null;
        synchronized (this) {
            defaultHostConfiguration = getHostConfiguration();
        }
        HostConfiguration methodConfiguration = new HostConfiguration(hostConfiguration);
        if (hostConfiguration != defaultHostConfiguration) {
            // we may need to apply some defaults
            if (!methodConfiguration.isHostSet()) {
                methodConfiguration.setHost(
                    defaultHostConfiguration.getHost(),
                    defaultHostConfiguration.getVirtualHost(),
                    defaultHostConfiguration.getPort(),
                    defaultHostConfiguration.getProtocol()
                );
            }
            if (!methodConfiguration.isProxySet() 
                && defaultHostConfiguration.isProxySet()) {
                    
                methodConfiguration.setProxy(
                    defaultHostConfiguration.getProxyHost(),
                    defaultHostConfiguration.getProxyPort() 
                );   
            }
            if (methodConfiguration.getLocalAddress() == null
                && defaultHostConfiguration.getLocalAddress() != null) {
                    
                methodConfiguration.setLocalAddress(defaultHostConfiguration.getLocalAddress());
            }
        }
        
        /* access all synchronized data in a single block, this will keeps us
         * from accessing data asynchronously as well having to regain the lock
         * for each item.
         */
        HttpMethodDirector methodDirector = null;
        synchronized (this) {
            methodDirector = new HttpMethodDirector(
                this.httpConnectionManager,
                methodConfiguration,
                this.params,
                (state == null ? getState() : state));
            defaultHostConfiguration = getHostConfiguration();
        }
        methodDirector.executeMethod(method);
        return method.getStatusCode();
    }

    /**
      * Returns the default host. 
      *
      * @return The default host.
      * 
      * @deprecated use #getHostConfiguration()
      */
     public String getHost() {
         return hostConfiguration.getHost();
     }

     /**
      * Returns the default port.
      *
      * @return The default port.
      * 
      * @deprecated use #getHostConfiguration()
      */
     public int getPort() {
         return hostConfiguration.getPort();
     }
     
    /**
     * Returns the {@link HostConfiguration host configuration} associated with the 
     * HttpClient.
     * 
     * @return {@link HostConfiguration host configuration}
     * 
     * @since 2.0
     */
    public synchronized HostConfiguration getHostConfiguration() {
        return hostConfiguration;
    }

    /**
     * Assigns the {@link HostConfiguration host configuration} to use with the
     * HttpClient.
     * 
     * @param hostConfiguration The {@link HostConfiguration host configuration} to set
     * 
     * @since 2.0
     */
    public synchronized void setHostConfiguration(HostConfiguration hostConfiguration) {
        this.hostConfiguration = hostConfiguration;
    }

    /**
     * Returns the {@link HttpConnectionManager HTTP connection manager} associated 
     * with the HttpClient.
     * 
     * @return {@link HttpConnectionManager HTTP connection manager}
     * 
     * @since 2.0
     */
    public synchronized HttpConnectionManager getHttpConnectionManager() {
        return httpConnectionManager;
    }

    /**
     * Assigns the {@link HttpConnectionManager HTTP connection manager} to use with
     * the HttpClient.
     * 
     * @param httpConnectionManager The {@link HttpConnectionManager HTTP connection manager}
     *  to set
     * 
     * @since 2.0
     */
    public synchronized void setHttpConnectionManager(
        HttpConnectionManager httpConnectionManager
    ) {
        this.httpConnectionManager = httpConnectionManager;
        if (this.httpConnectionManager != null) {
            this.httpConnectionManager.getParams().setDefaults(this.params);
        }
    }

    /**
     * Returns {@link HttpClientParams HTTP protocol parameters} associated with this HttpClient.
     * 
     * @since 3.0
     * 
     * @see HttpClientParams
     */
    public HttpClientParams getParams() {
        return this.params;
    }

    /**
     * Assigns {@link HttpClientParams HTTP protocol parameters} for this HttpClient.
     * 
     * @since 3.0
     * 
     * @see HttpClientParams
     */
    public void setParams(final HttpClientParams params) {
        if (params == null) {
            throw new IllegalArgumentException("Parameters may not be null");
        }
        this.params = params;
    }

}