/*

 * Copyright (c) 1997, 2005, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package javax.activation;

import java.util.*;

import java.io.*;

import java.net.*;

import com.sun.activation.registries.MailcapFile;

import com.sun.activation.registries.LogSupport;

/**

 * MailcapCommandMap extends the CommandMap

 * abstract class. It implements a CommandMap whose configuration

 * is based on mailcap files

 * (<A HREF="http://www.ietf.org/rfc/rfc1524.txt">RFC 1524</A>).

 * The MailcapCommandMap can be configured both programmatically

 * and via configuration files.

 * <p>

 * <b>Mailcap file search order:</b><p>

 * The MailcapCommandMap looks in various places in the user's

 * system for mailcap file entries. When requests are made

 * to search for commands in the MailcapCommandMap, it searches

 * mailcap files in the following order:

 * <p>

 * <ol>

 * <li> Programatically added entries to the MailcapCommandMap instance.

 * <li> The file <code>.mailcap</code> in the user's home directory.

 * <li> The file &lt;<i>java.home</i>&gt;<code>/lib/mailcap</code>.

 * <li> The file or resources named <code>META-INF/mailcap</code>.

 * <li> The file or resource named <code>META-INF/mailcap.default</code>

 * (usually found only in the <code>activation.jar</code> file).

 * </ol>

 * <p>

 * <b>Mailcap file format:</b><p>

 *

 * Mailcap files must conform to the mailcap

 * file specification (RFC 1524, <i>A User Agent Configuration Mechanism

 * For Multimedia Mail Format Information</i>).

 * The file format consists of entries corresponding to

 * particular MIME types. In general, the specification

 * specifies <i>applications</i> for clients to use when they

 * themselves cannot operate on the specified MIME type. The

 * MailcapCommandMap extends this specification by using a parameter mechanism

 * in mailcap files that allows JavaBeans(tm) components to be specified as

 * corresponding to particular commands for a MIME type.<p>

 *

 * When a mailcap file is

 * parsed, the MailcapCommandMap recognizes certain parameter signatures,

 * specifically those parameter names that begin with <code>x-java-</code>.

 * The MailcapCommandMap uses this signature to find

 * command entries for inclusion into its registries.

 * Parameter names with the form <code>x-java-&lt;name></code>

 * are read by the MailcapCommandMap as identifying a command

 * with the name <i>name</i>. When the <i>name</i> is <code>

 * content-handler</code> the MailcapCommandMap recognizes the class

 * signified by this parameter as a <i>DataContentHandler</i>.

 * All other commands are handled generically regardless of command

 * name. The command implementation is specified by a fully qualified

 * class name of a JavaBean(tm) component. For example; a command for viewing

 * some data can be specified as: <code>x-java-view=com.foo.ViewBean</code>.<p>

 *

 * When the command name is <code>fallback-entry</code>, the value of

 * the command may be <code>true</code> or <code>false</code>.  An

 * entry for a MIME type that includes a parameter of

 * <code>x-java-fallback-entry=true</code> defines fallback commands

 * for that MIME type that will only be used if no non-fallback entry

 * can be found.  For example, an entry of the form <code>text/*; ;

 * x-java-fallback-entry=true; x-java-view=com.sun.TextViewer</code>

 * specifies a view command to be used for any text MIME type.  This

 * view command would only be used if a non-fallback view command for

 * the MIME type could not be found.<p>

 *

 * MailcapCommandMap aware mailcap files have the

 * following general form:<p>

 * <code>

 * # Comments begin with a '#' and continue to the end of the line.<br>

 * &lt;mime type>; ; &lt;parameter list><br>

 * # Where a parameter list consists of one or more parameters,<br>

 * # where parameters look like: x-java-view=com.sun.TextViewer<br>

 * # and a parameter list looks like: <br>

 * text/plain; ; x-java-view=com.sun.TextViewer; x-java-edit=com.sun.TextEdit

 * <br>

 * # Note that mailcap entries that do not contain 'x-java' parameters<br>

 * # and comply to RFC 1524 are simply ignored:<br>

 * image/gif; /usr/dt/bin/sdtimage %s<br>

 *

 * </code>

 * <p>

 *

 * @author Bart Calder

 * @author Bill Shannon

 *

 * @since 1.6

 */

public class MailcapCommandMap extends CommandMap {

    /*

     * We manage a collection of databases, searched in order.

     * The default database is shared between all instances

     * of this class.

     * XXX - Can we safely share more databases between instances?

     */

    private static MailcapFile defDB = null;

    private MailcapFile[] DB;

    private static final int PROG = 0;  // programmatically added entries

    /**

     * The default Constructor.

     */

    public MailcapCommandMap() {

        super();

        List dbv = new ArrayList(5);    // usually 5 or less databases

        MailcapFile mf = null;

        dbv.add(null);          // place holder for PROG entry

        LogSupport.log("MailcapCommandMap: load HOME");

        try {

            String user_home = System.getProperty("user.home");

            if (user_home != null) {

                String path = user_home + File.separator + ".mailcap";

                mf = loadFile(path);

                if (mf != null)

                    dbv.add(mf);

            }

        } catch (SecurityException ex) {}

        LogSupport.log("MailcapCommandMap: load SYS");

        try {

            // check system's home

            String system_mailcap = System.getProperty("java.home") +

                File.separator + "lib" + File.separator + "mailcap";

            mf = loadFile(system_mailcap);

            if (mf != null)

                dbv.add(mf);

        } catch (SecurityException ex) {}

        LogSupport.log("MailcapCommandMap: load JAR");

        // load from the app's jar file

        loadAllResources(dbv, "META-INF/mailcap");

        LogSupport.log("MailcapCommandMap: load DEF");

        synchronized (MailcapCommandMap.class) {

            // see if another instance has created this yet.

            if (defDB == null)

                defDB = loadResource("/META-INF/mailcap.default");

        }

        if (defDB != null)

            dbv.add(defDB);

        DB = new MailcapFile[dbv.size()];

        DB = (MailcapFile[])dbv.toArray(DB);

    }

    /**

     * Load from the named resource.

     */

    private MailcapFile loadResource(String name) {

        InputStream clis = null;

        try {

            clis = SecuritySupport.getResourceAsStream(this.getClass(), name);

            if (clis != null) {

                MailcapFile mf = new MailcapFile(clis);

                if (LogSupport.isLoggable())

                    LogSupport.log("MailcapCommandMap: successfully loaded " +

                        "mailcap file: " + name);

                return mf;

            } else {

                if (LogSupport.isLoggable())

                    LogSupport.log("MailcapCommandMap: not loading " +

                        "mailcap file: " + name);

            }

        } catch (IOException e) {

            if (LogSupport.isLoggable())

                LogSupport.log("MailcapCommandMap: can't load " + name, e);

        } catch (SecurityException sex) {

            if (LogSupport.isLoggable())

                LogSupport.log("MailcapCommandMap: can't load " + name, sex);

        } finally {

            try {

                if (clis != null)

                    clis.close();

            } catch (IOException ex) { }        // ignore it

        }

        return null;

    }

    /**

     * Load all of the named resource.

     */

    private void loadAllResources(List v, String name) {

        boolean anyLoaded = false;

        try {

            URL[] urls;

            ClassLoader cld = null;

            // First try the "application's" class loader.

            cld = SecuritySupport.getContextClassLoader();

            if (cld == null)

                cld = this.getClass().getClassLoader();

            if (cld != null)

                urls = SecuritySupport.getResources(cld, name);

            else

                urls = SecuritySupport.getSystemResources(name);

            if (urls != null) {

                if (LogSupport.isLoggable())

                    LogSupport.log("MailcapCommandMap: getResources");

                for (int i = 0; i < urls.length; i++) {

                    URL url = urls[i];

                    InputStream clis = null;

                    if (LogSupport.isLoggable())

                        LogSupport.log("MailcapCommandMap: URL " + url);

                    try {

                        clis = SecuritySupport.openStream(url);

                        if (clis != null) {

                            v.add(new MailcapFile(clis));

                            anyLoaded = true;

                            if (LogSupport.isLoggable())

                                LogSupport.log("MailcapCommandMap: " +

                                    "successfully loaded " +

                                    "mailcap file from URL: " +

                                    url);

                        } else {

                            if (LogSupport.isLoggable())

                                LogSupport.log("MailcapCommandMap: " +

                                    "not loading mailcap " +

                                    "file from URL: " + url);

                        }

                    } catch (IOException ioex) {

                        if (LogSupport.isLoggable())

                            LogSupport.log("MailcapCommandMap: can't load " +

                                                url, ioex);

                    } catch (SecurityException sex) {

                        if (LogSupport.isLoggable())

                            LogSupport.log("MailcapCommandMap: can't load " +

                                                url, sex);

                    } finally {

                        try {

                            if (clis != null)

                                clis.close();

                        } catch (IOException cex) { }

                    }

                }

            }

        } catch (Exception ex) {

            if (LogSupport.isLoggable())

                LogSupport.log("MailcapCommandMap: can't load " + name, ex);

        }

        // if failed to load anything, fall back to old technique, just in case

        if (!anyLoaded) {

            if (LogSupport.isLoggable())

                LogSupport.log("MailcapCommandMap: !anyLoaded");

            MailcapFile mf = loadResource("/" + name);

            if (mf != null)

                v.add(mf);

        }

    }

    /**

     * Load from the named file.

     */

    private MailcapFile loadFile(String name) {

        MailcapFile mtf = null;

        try {

            mtf = new MailcapFile(name);

        } catch (IOException e) {

            //  e.printStackTrace();

        }

        return mtf;

    }

    /**

     * Constructor that allows the caller to specify the path

     * of a <i>mailcap</i> file.

     *

     * @param fileName The name of the <i>mailcap</i> file to open

     * @exception       IOException     if the file can't be accessed

     */

    public MailcapCommandMap(String fileName) throws IOException {

        this();

        if (LogSupport.isLoggable())

            LogSupport.log("MailcapCommandMap: load PROG from " + fileName);

        if (DB[PROG] == null) {

            DB[PROG] = new MailcapFile(fileName);

        }

    }

    /**

     * Constructor that allows the caller to specify an <i>InputStream</i>

     * containing a mailcap file.

     *

     * @param is        InputStream of the <i>mailcap</i> file to open

     */

    public MailcapCommandMap(InputStream is) {

        this();

        LogSupport.log("MailcapCommandMap: load PROG");

        if (DB[PROG] == null) {

            try {

                DB[PROG] = new MailcapFile(is);

            } catch (IOException ex) {

                // XXX - should throw it

            }

        }

    }

    /**

     * Get the preferred command list for a MIME Type. The MailcapCommandMap

     * searches the mailcap files as described above under

     * <i>Mailcap file search order</i>.<p>

     *

     * The result of the search is a proper subset of available

     * commands in all mailcap files known to this instance of

     * MailcapCommandMap.  The first entry for a particular command

     * is considered the preferred command.

     *

     * @param mimeType  the MIME type

     * @return the CommandInfo objects representing the preferred commands.

     */

    public synchronized CommandInfo[] getPreferredCommands(String mimeType) {

        List cmdList = new ArrayList();

        if (mimeType != null)

            mimeType = mimeType.toLowerCase(Locale.ENGLISH);

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapList(mimeType);

            if (cmdMap != null)

                appendPrefCmdsToList(cmdMap, cmdList);

        }

        // now add the fallback commands

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapFallbackList(mimeType);

            if (cmdMap != null)

                appendPrefCmdsToList(cmdMap, cmdList);

        }

        CommandInfo[] cmdInfos = new CommandInfo[cmdList.size()];

        cmdInfos = (CommandInfo[])cmdList.toArray(cmdInfos);

        return cmdInfos;

    }

    /**

     * Put the commands that are in the hash table, into the list.

     */

    private void appendPrefCmdsToList(Map cmdHash, List cmdList) {

        Iterator verb_enum = cmdHash.keySet().iterator();

        while (verb_enum.hasNext()) {

            String verb = (String)verb_enum.next();

            if (!checkForVerb(cmdList, verb)) {

                List cmdList2 = (List)cmdHash.get(verb); // get the list

                String className = (String)cmdList2.get(0);

                cmdList.add(new CommandInfo(verb, className));

            }

        }

    }

    /**

     * Check the cmdList to see if this command exists, return

     * true if the verb is there.

     */

    private boolean checkForVerb(List cmdList, String verb) {

        Iterator ee = cmdList.iterator();

        while (ee.hasNext()) {

            String enum_verb =

                (String)((CommandInfo)ee.next()).getCommandName();

            if (enum_verb.equals(verb))

                return true;

        }

        return false;

    }

    /**

     * Get all the available commands in all mailcap files known to

     * this instance of MailcapCommandMap for this MIME type.

     *

     * @param mimeType  the MIME type

     * @return the CommandInfo objects representing all the commands.

     */

    public synchronized CommandInfo[] getAllCommands(String mimeType) {

        List cmdList = new ArrayList();

        if (mimeType != null)

            mimeType = mimeType.toLowerCase(Locale.ENGLISH);

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapList(mimeType);

            if (cmdMap != null)

                appendCmdsToList(cmdMap, cmdList);

        }

        // now add the fallback commands

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapFallbackList(mimeType);

            if (cmdMap != null)

                appendCmdsToList(cmdMap, cmdList);

        }

        CommandInfo[] cmdInfos = new CommandInfo[cmdList.size()];

        cmdInfos = (CommandInfo[])cmdList.toArray(cmdInfos);

        return cmdInfos;

    }

    /**

     * Put the commands that are in the hash table, into the list.

     */

    private void appendCmdsToList(Map typeHash, List cmdList) {

        Iterator verb_enum = typeHash.keySet().iterator();

        while (verb_enum.hasNext()) {

            String verb = (String)verb_enum.next();

            List cmdList2 = (List)typeHash.get(verb);

            Iterator cmd_enum = ((List)cmdList2).iterator();

            while (cmd_enum.hasNext()) {

                String cmd = (String)cmd_enum.next();

                cmdList.add(new CommandInfo(verb, cmd));

                // cmdList.add(0, new CommandInfo(verb, cmd));

            }

        }

    }

    /**

     * Get the command corresponding to <code>cmdName</code> for the MIME type.

     *

     * @param mimeType  the MIME type

     * @param cmdName   the command name

     * @return the CommandInfo object corresponding to the command.

     */

    public synchronized CommandInfo getCommand(String mimeType,

                                                        String cmdName) {

        if (mimeType != null)

            mimeType = mimeType.toLowerCase(Locale.ENGLISH);

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapList(mimeType);

            if (cmdMap != null) {

                // get the cmd list for the cmd

                List v = (List)cmdMap.get(cmdName);

                if (v != null) {

                    String cmdClassName = (String)v.get(0);

                    if (cmdClassName != null)

                        return new CommandInfo(cmdName, cmdClassName);

                }

            }

        }

        // now try the fallback list

        for (int i = 0; i < DB.length; i++) {

            if (DB[i] == null)

                continue;

            Map cmdMap = DB[i].getMailcapFallbackList(mimeType);

            if (cmdMap != null) {

                // get the cmd list for the cmd

                List v = (List)cmdMap.get(cmdName);

                if (v != null) {

                    String cmdClassName = (String)v.get(0);

                    if (cmdClassName != null)

                        return new CommandInfo(cmdName, cmdClassName);

                }

            }

        }

        return null;

    }

    /**

     * Add entries to the registry.  Programmatically

     * added entries are searched before other entries.<p>

     *

     * The string that is passed in should be in mailcap

     * format.

     *

     * @param mail_cap a correctly formatted mailcap string

     */

    public synchronized void addMailcap(String mail_cap) {

        // check to see if one exists

        LogSupport.log("MailcapCommandMap: add to PROG");

        if (DB[PROG] == null)

            DB[PROG] = new MailcapFile();

        DB[PROG].appendToMailcap(mail_cap);

    }

    /**

     * Return the DataContentHandler for the specified MIME type.

     *