/*

 * 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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.net.www;

import java.io.*;

import java.util.Calendar;

import java.util.Date;

import java.text.SimpleDateFormat;

import java.net.URL;

import java.net.FileNameMap;

import java.util.Hashtable;

import java.util.Enumeration;

import java.util.Properties;

import java.util.StringTokenizer;

public class MimeTable implements FileNameMap {

    /** Keyed by content type, returns MimeEntries */

    private Hashtable<String, MimeEntry> entries

        = new Hashtable<String, MimeEntry>();

    /** Keyed by file extension (with the .), returns MimeEntries */

    private Hashtable<String, MimeEntry> extensionMap

        = new Hashtable<String, MimeEntry>();

    // Will be reset if in the platform-specific data file

    private static String tempFileTemplate;

    static {

        java.security.AccessController.doPrivileged(

            new java.security.PrivilegedAction<Void>() {

                public Void run() {

                tempFileTemplate =

                    System.getProperty("content.types.temp.file.template",

                                       "/tmp/%s");

                mailcapLocations = new String[] {

                    System.getProperty("user.mailcap"),

                    System.getProperty("user.home") + "/.mailcap",

                    "/etc/mailcap",

                    "/usr/etc/mailcap",

                    "/usr/local/etc/mailcap",

                    System.getProperty("hotjava.home",

                                           "/usr/local/hotjava")

                        + "/lib/mailcap",

                };

                return null;

            }

        });

    }

    private static final String filePreamble = "sun.net.www MIME content-types table";

    private static final String fileMagic = "#" + filePreamble;

    private static MimeTable defaultInstance = null;

    MimeTable() {

        load();

    }

    /**

     * Get the single instance of this class.  First use will load the

     * table from a data file.

     */

    public static MimeTable getDefaultTable() {

        if (defaultInstance == null) {

            java.security.AccessController.doPrivileged(

                new java.security.PrivilegedAction<Void>() {

                    public Void run() {

                    defaultInstance = new MimeTable();

                    URLConnection.setFileNameMap(defaultInstance);

                    return null;

                }

            });

        }

        return defaultInstance;

    }

    /**

     *

     */

    public static FileNameMap loadTable() {

        MimeTable mt = getDefaultTable();

        return (FileNameMap)mt;

    }

    public synchronized int getSize() {

        return entries.size();

    }

    public synchronized String getContentTypeFor(String fileName) {

        MimeEntry entry = findByFileName(fileName);

        if (entry != null) {

            return entry.getType();

        } else {

            return null;

        }

    }

    public synchronized void add(MimeEntry m) {

        entries.put(m.getType(), m);

        String exts[] = m.getExtensions();

        if (exts == null) {

            return;

        }

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

            extensionMap.put(exts[i], m);

        }

    }

    public synchronized MimeEntry remove(String type) {

        MimeEntry entry = entries.get(type);

        return remove(entry);

    }

    public synchronized MimeEntry remove(MimeEntry entry) {

        String[] extensionKeys = entry.getExtensions();

        if (extensionKeys != null) {

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

                extensionMap.remove(extensionKeys[i]);

            }

        }

        return entries.remove(entry.getType());

    }

    public synchronized MimeEntry find(String type) {

        MimeEntry entry = entries.get(type);

        if (entry == null) {

            // try a wildcard lookup

            Enumeration<MimeEntry> e = entries.elements();

            while (e.hasMoreElements()) {

                MimeEntry wild = e.nextElement();

                if (wild.matches(type)) {

                    return wild;

                }

            }

        }

        return entry;

    }

    /**

     * Locate a MimeEntry by the file extension that has been associated

     * with it. Parses general file names, and URLs.

     */

    public MimeEntry findByFileName(String fname) {

        String ext = "";

        int i = fname.lastIndexOf('#');

        if (i > 0) {

            fname = fname.substring(0, i - 1);

        }

        i = fname.lastIndexOf('.');

        // REMIND: OS specific delimters appear here

        i = Math.max(i, fname.lastIndexOf('/'));

        i = Math.max(i, fname.lastIndexOf('?'));

        if (i != -1 && fname.charAt(i) == '.') {

            ext = fname.substring(i).toLowerCase();

        }

        return findByExt(ext);

    }

    /**

     * Locate a MimeEntry by the file extension that has been associated

     * with it.

     */

    public synchronized MimeEntry findByExt(String fileExtension) {

        return extensionMap.get(fileExtension);

    }

    public synchronized MimeEntry findByDescription(String description) {

        Enumeration<MimeEntry> e = elements();

        while (e.hasMoreElements()) {

            MimeEntry entry = e.nextElement();

            if (description.equals(entry.getDescription())) {

                return entry;

            }

        }

        // We failed, now try treating description as type

        return find(description);

    }

    String getTempFileTemplate() {

        return tempFileTemplate;

    }

    public synchronized Enumeration<MimeEntry> elements() {

        return entries.elements();

    }

    // For backward compatibility -- mailcap format files

    // This is not currently used, but may in the future when we add ability

    // to read BOTH the properties format and the mailcap format.

    protected static String[] mailcapLocations;

    public synchronized void load() {

        Properties entries = new Properties();

        File file = null;

        try {

            InputStream is;

            // First try to load the user-specific table, if it exists

            String userTablePath =

                System.getProperty("content.types.user.table");

            if (userTablePath != null) {

                file = new File(userTablePath);

                if (!file.exists()) {

                    // No user-table, try to load the default built-in table.

                    file = new File(System.getProperty("java.home") +

                                    File.separator +

                                    "lib" +

                                    File.separator +

                                    "content-types.properties");

                }

            }

            else {

                // No user table, try to load the default built-in table.

                file = new File(System.getProperty("java.home") +

                                File.separator +

                                "lib" +

                                File.separator +

                                "content-types.properties");

            }

            is = new BufferedInputStream(new FileInputStream(file));

            entries.load(is);

            is.close();

        }

        catch (IOException e) {

            System.err.println("Warning: default mime table not found: " +

                               file.getPath());

            return;

        }

        parse(entries);

    }

    void parse(Properties entries) {

        // first, strip out the platform-specific temp file template

        String tempFileTemplate = (String)entries.get("temp.file.template");

        if (tempFileTemplate != null) {

            entries.remove("temp.file.template");

            this.tempFileTemplate = tempFileTemplate;

        }

        // now, parse the mime-type spec's

        Enumeration<?> types = entries.propertyNames();

        while (types.hasMoreElements()) {

            String type = (String)types.nextElement();

            String attrs = entries.getProperty(type);

            parse(type, attrs);

        }

    }

    //

    // Table format:

    //

    // <entry> ::= <table_tag> | <type_entry>

    //

    // <table_tag> ::= <table_format_version> | <temp_file_template>

    //

    // <type_entry> ::= <type_subtype_pair> '=' <type_attrs_list>

    //

    // <type_subtype_pair> ::= <type> '/' <subtype>

    //

    // <type_attrs_list> ::= <attr_value_pair> [ ';' <attr_value_pair> ]*

    //                       | [ <attr_value_pair> ]+

    //

    // <attr_value_pair> ::= <attr_name> '=' <attr_value>

    //

    // <attr_name> ::= 'description' | 'action' | 'application'

    //                 | 'file_extensions' | 'icon'

    //

    // <attr_value> ::= <legal_char>*

    //

    // Embedded ';' in an <attr_value> are quoted with leading '\' .

    //

    // Interpretation of <attr_value> depends on the <attr_name> it is

    // associated with.

    //

    void parse(String type, String attrs) {

        MimeEntry newEntry = new MimeEntry(type);

        // REMIND handle embedded ';' and '|' and literal '"'

        StringTokenizer tokenizer = new StringTokenizer(attrs, ";");

        while (tokenizer.hasMoreTokens()) {

            String pair = tokenizer.nextToken();

            parse(pair, newEntry);

        }

        add(newEntry);

    }

    void parse(String pair, MimeEntry entry) {

        // REMIND add exception handling...

        String name = null;

        String value = null;

        boolean gotName = false;

        StringTokenizer tokenizer = new StringTokenizer(pair, "=");

        while (tokenizer.hasMoreTokens()) {

            if (gotName) {

                value = tokenizer.nextToken().trim();

            }

            else {

                name = tokenizer.nextToken().trim();

                gotName = true;

            }

        }

        fill(entry, name, value);

    }

    void fill(MimeEntry entry, String name, String value) {

        if ("description".equalsIgnoreCase(name)) {

            entry.setDescription(value);

        }

        else if ("action".equalsIgnoreCase(name)) {

            entry.setAction(getActionCode(value));

        }

        else if ("application".equalsIgnoreCase(name)) {

            entry.setCommand(value);

        }

        else if ("icon".equalsIgnoreCase(name)) {

            entry.setImageFileName(value);

        }

        else if ("file_extensions".equalsIgnoreCase(name)) {

            entry.setExtensions(value);

        }

        // else illegal name exception

    }

    String[] getExtensions(String list) {

        StringTokenizer tokenizer = new StringTokenizer(list, ",");

        int n = tokenizer.countTokens();

        String[] extensions = new String[n];

        for (int i = 0; i < n; i++) {

            extensions[i] = tokenizer.nextToken();

        }

        return extensions;

    }

    int getActionCode(String action) {

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

            if (action.equalsIgnoreCase(MimeEntry.actionKeywords[i])) {

                return i;

            }

        }

        return MimeEntry.UNKNOWN;

    }

    public synchronized boolean save(String filename) {

        if (filename == null) {

            filename = System.getProperty("user.home" +

                                          File.separator +

                                          "lib" +

                                          File.separator +

                                          "content-types.properties");

        }

        return saveAsProperties(new File(filename));

    }

    public Properties getAsProperties() {

        Properties properties = new Properties();

        Enumeration<MimeEntry> e = elements();

        while (e.hasMoreElements()) {

            MimeEntry entry = e.nextElement();

            properties.put(entry.getType(), entry.toProperty());

        }

        return properties;

    }

    protected boolean saveAsProperties(File file) {

        FileOutputStream os = null;

        try {

            os = new FileOutputStream(file);

            Properties properties = getAsProperties();

            properties.put("temp.file.template", tempFileTemplate);

            String tag;

            String user = System.getProperty("user.name");

            if (user != null) {

                tag = "; customized for " + user;

                properties.save(os, filePreamble + tag);

            }

            else {

                properties.save(os, filePreamble);

            }

        }

        catch (IOException e) {

            e.printStackTrace();

            return false;

        }

        finally {

            if (os != null) {

                try { os.close(); } catch (IOException e) {}

            }

        }

        return true;

    }

    /*

     * Debugging utilities

     *

    public void list(PrintStream out) {

        Enumeration keys = entries.keys();

        while (keys.hasMoreElements()) {

            String key = (String)keys.nextElement();

            MimeEntry entry = (MimeEntry)entries.get(key);

            out.println(key + ": " + entry);

        }

    }

    public static void main(String[] args) {

        MimeTable testTable = MimeTable.getDefaultTable();

        Enumeration e = testTable.elements();

        while (e.hasMoreElements()) {

            MimeEntry entry = (MimeEntry)e.nextElement();

            System.out.println(entry);

        }

        testTable.save(File.separator + "tmp" +

                       File.separator + "mime_table.save");

    }

    */

}