/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2000 Blacksmith, Inc.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.web;

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Locale;
import java.util.Map;

import net.wotonomy.foundation.NSArray;
import net.wotonomy.foundation.NSData;
import net.wotonomy.foundation.NSKeyValueCoding;
import net.wotonomy.foundation.NSMutableDictionary;
import net.wotonomy.foundation.internal.PropertyListParser;

/**
* Manages all resources vended by the application.
*
* @author michael@mpowers.net
* @author $Author: cgruber $
* @version $Revision: 905 $
*/
public class WOResourceManager
{
    private NSMutableDictionary resourceCache;
    private NSMutableDictionary dynamicDataCache;
    private NSMutableDictionary stringTableCache;
    private Map localeCache; // used for wo-style i18n
    private Locale californiaLocale; // used for wo-style i18n

    /**
    * Constructor is only accessible to subclasses.
    */    
    protected WOResourceManager()
    {
        resourceCache = new NSMutableDictionary();
        dynamicDataCache = new NSMutableDictionary();
        stringTableCache = new NSMutableDictionary();
        localeCache = new HashMap();
        californiaLocale = new Locale( "en", "US" );
        localeCache.put( "en", californiaLocale );
    }
    
    /**
    * Returns the raw data corresponding to the specified resource.
    * Any data retrieved by this method will be placed in the 
    * resource manager's global cache.
    */
    public byte[] bytesForResourceNamed(String aFileName,
                                        String aFrameworkName,
                                        NSArray aLanguagesList)
    {
        String mash = aFileName + aFrameworkName;
        if ( aLanguagesList != null )
        {
            mash = mash + aLanguagesList.componentsJoinedByString(":");
        }
        
        byte[] result = (byte[]) resourceCache.objectForKey( mash );
        if ( result == null )
        {
            InputStream input = inputStreamForResourceNamed(
                aFileName, aFrameworkName, aLanguagesList );
            if ( input != null )
            {
                try
                {
                    int c;
                    ByteArrayOutputStream output = new ByteArrayOutputStream();
                    while ( ( c = input.read() ) != -1 )
                    {
                        output.write( c );
                    }
                    output.flush();
                    input.close();
                    output.close();
                    result = output.toByteArray();
                    synchronized ( resourceCache )
                    {
                        resourceCache.setObjectForKey( result, mash );
                    }
                 }
                 catch ( Throwable t )
                 {
                     System.err.println( "WOResourceManager: Error reading bytes: " + aFileName );
                     t.printStackTrace();
                 }
             }
        }
        return result;
    }
                                        
    /**
    * Returns the content type corresponding to the specified resource.
    * This implementation recognizes gif, jpg, png, html, and xml extensions.
    * Otherwise, "text/plain" is returned.
    */
    public String contentTypeForResourceNamed(String aResourcePath)
    {
        if ( aResourcePath.endsWith( ".gif" ) ) return "image/gif";
        if ( aResourcePath.endsWith( ".jpg" ) ) return "image/jpeg";
        if ( aResourcePath.endsWith( ".png" ) ) return "image/png";
        if ( aResourcePath.endsWith( ".html" ) ) return "text/html";
        if ( aResourcePath.endsWith( ".xml" ) ) return "text/xml";
        return "text/plain";
    }
    
    /**
    * Returns a url to be used when errors occur while retrieving a resource.
    */
    public String errorMessageUrlForResourceNamed(String aResourceName,
                                                  String aFrameworkName)
    {
        if ( aResourceName == null ) aResourceName = "null";
        if ( aFrameworkName == null ) 
        {
            return "/ERROR/NOT_FOUND/app=" +
                WOApplication.application().name() +
                "/filename=" + aResourceName;
        }
        else
        {
            return "/ERROR/NOT_FOUND/framework=" +
                aFrameworkName + "/filename=" + aResourceName;
        }
        
    }
         
    /**
    * Clears all cached system-wide resource data.
    */                                         
    public void flushDataCache()
    {
        synchronized ( resourceCache )
        {
            resourceCache.removeAllObjects();
        }
        synchronized ( dynamicDataCache )
        {
            dynamicDataCache.removeAllObjects();
        }
        synchronized ( stringTableCache )
        {
            stringTableCache.removeAllObjects();
        }
    }
    
    /**
    * Returns the file-system path for the specified resource.
    * Deprecated and not implemented.
    * @deprecated Use inputStreamForResourceNamed instead.
    */
    public String pathForResourceNamed(String aResourceName,
                                       String aFrameworkName,
                                       NSArray aLanguagesList)
    {
        throw new RuntimeException( "ResourceManager.pathForResourceNamed: deprecated" );
    }
                     
    /**
    * Removes the data from the dynamic data cache for the specified session.
    * If aSession is null, the data is removed from the application-wide
    * data cache.
    */                     
    public void removeDataForKey(String aKey,
                                 WOSession aSession)
    {
        if ( aSession != null )
        {
            if ( aSession.dynamicDataCache != null )
            {
                aSession.dynamicDataCache.removeObjectForKey( aKey );
            }
        }
        else
        {
            synchronized ( dynamicDataCache )
            {
                dynamicDataCache.removeObjectForKey( aKey );
            }
        }
    }
    
    /**
    * Sets the data in the dynamic data cache for the specified session.
    * If aSession is null, the data is placed in the application-wide
    * data cache.  If the key is a system-generated key, the data will
    * be removed by calling removeData() the next time it is requested.
    */                     
    public void setData(NSData someData,
                        String key,
                        String type,
                        WOSession aSession)
    {
        if ( aSession != null )
        {
            if ( aSession.dynamicDataCache != null )
            {
                aSession.dynamicDataCache.setObjectForKey(
                    new TypedData( type, someData ), key );
            }
        }
        else
        {
            synchronized ( dynamicDataCache )
            {
                dynamicDataCache.setObjectForKey(
                    new TypedData( type, someData ), key );
            }
        }
    }
    
    /**
    * Returns a localized string from a property list for 
    * a given key. If the key doesn't exist, aDefaultValue 
    * is returned.
    */
    public String stringForKey(String aKey,
                               String aFileName,
                               String aDefaultValue,
                               String aFrameworkName,
                               NSArray aLanguagesList)
    {
        
        String mash = aFileName + aFrameworkName;
        if ( aLanguagesList != null )
        {
            mash = mash + aLanguagesList.componentsJoinedByString(":");
        }
        
        Object table = stringTableCache.objectForKey( mash );
        if ( table == null )
        {
            try
            {
                InputStream input = (InputStream) inputStreamForResourceNamed(
                    aFileName, aFrameworkName, aLanguagesList);
                if ( input != null )
                {
                    Reader reader = 
                        new BufferedReader(new InputStreamReader(input));
                    table = PropertyListParser.propertyListFromReader( reader );
                    synchronized ( stringTableCache )
                    {
                        stringTableCache.setObjectForKey( table, mash );
                    }
                }
            }
            catch ( IOException ioe )
            {
                System.err.println( "WOResourceManager: error reading: " + aFileName );
                ioe.printStackTrace();
            }
            catch ( Throwable t )
            {
                // could not parse
                System.err.println( "WOResourceManager: could not parse: " + aFileName );
                System.err.println( t );
            }
        }
        
        Object result = null;
        if ( table != null )
        {
            result = NSKeyValueCoding.DefaultImplementation.valueForKey( table, aKey );
        }
        if ( result == null )
        {
            result = aDefaultValue;
        }
        else
        {
            result = result.toString();
        }
        
        return (String) result;
    }
        
    /**
    * Returns a url that invokes the resource manager for the
    * specified resource.
    */                        
    public String urlForResourceNamed(String aResourceName,
                                      String aFrameworkName,
                                      NSArray aLanguagesList,
                                      WORequest aRequest)
    {
        StringBuffer buffer = new StringBuffer();
        if ( aFrameworkName == null )
        {
            aFrameworkName = "application";
        }
        buffer.append( aRequest.applicationName() );
        buffer.append( '/' );
        buffer.append( WOApplication.resourceRequestHandlerKey() );
        if ( !aFrameworkName.startsWith("/") )
        {
            buffer.append( '/' );
        }
        buffer.append( aFrameworkName );
        buffer.append( '/' );
        buffer.append( aResourceName );
        return buffer.toString();
    }
                                        
    /**
    * Returns an input for the raw resource.  Data returned by
    * this method will not be put in the resource manager's global cache.
    */
    public InputStream inputStreamForResourceNamed(String aResourceName,
                                                   String aFrameworkName,
                                                   NSArray aLanguagesList)
    {
        if ( aResourceName == null ) return null;
        InputStream result = null;
        
        StringBuffer path = new StringBuffer();
        path.append( '/' );
        if ( aFrameworkName != null ) 
        {
            path.append( aFrameworkName ).append( '/' );
        }
        
        int i = aResourceName.lastIndexOf( "." );
        if ( i != -1 ) 
            path.append( aResourceName.substring( 0, i ) );
        else
            path.append( aResourceName );

        String location = path.toString();
        if ( aLanguagesList != null )
        {
            String language;
            Locale locale;
            HashSet tried = new HashSet(5);
            Enumeration e = aLanguagesList.objectEnumerator();
            while ( e.hasMoreElements() && result == null )
            {
                language = e.nextElement().toString();
                
                // look for java-style localization
                if ( i != -1 )
                {
                    result = getStream( location + '_' 
                        + language + aResourceName.substring( i ) );
                }
                else // no dot extension
                {
                    result = getStream( location + '_' + language );
                }
                
                // look for wo-style localization
                if ( result == null )
                {
                    locale = (Locale) localeCache.get( language );
                    if ( locale == null )
                    {
                        if ( language.length() == 5 )
                        {
                            locale = new Locale( 
                                language.substring( 0, 2 ), 
                                language.substring( 3, 5 ) );
                        }
                        else
                        {
                            locale = new Locale( language, "" );
                        }
                        synchronized ( localeCache )
                        {
                            localeCache.put( language, locale );
                        }
                    }
                    
                    language = '/'+locale.getDisplayLanguage( californiaLocale )+".lproj";
                    if ( !tried.contains( language ) )
                    {
                        if ( aFrameworkName != null )
                        {
                            int j = aFrameworkName.length()+1;
                            path.insert( j, language ); 
                            result = getStream( path.toString() + aResourceName.substring( i ) );
                            path.delete( j, j+language.length() );
                        }
                        else
                        {
                            result = getStream( language + path.toString() + aResourceName.substring( i ) );
                        }
                        tried.add( language );
                    }
                }
            }
        }            
        
        // look for file in package        
        if ( result == null )
        {
            if ( i != -1 )
            {
                result = getStream( path.append( 
                    aResourceName.substring( i ) ).toString() );
            }
            else // no dot extension
            {
                result = getStream( location );
            }
        }

        return result;
    }
    
    private static final InputStream getStream( String path )
    { //System.out.println( "getStream: " + path );        
        InputStream input = 
            WOApplication.application().getClass().getResourceAsStream( path );
        if ( input == null )
        {
            // in case the local class loader doesn't delegate to its parent
            input = ClassLoader.getSystemResourceAsStream( path );
        }                    
        return input;
    }
    
    private static final class TypedData
    {
        String type;
        NSData data;
        
        public TypedData( String aType, NSData aData )
        {
            type = aType;
            data = aData;
        }
    }
}

/*
 * $Log$
 * Revision 1.2  2006/02/19 01:44:02  cgruber
 * Add xmlrpc files
 * Remove jclark and replace with dom4j and javax.xml.sax stuff
 * Re-work dependencies and imports so it all compiles.
 *
 * Revision 1.1  2006/02/16 13:22:22  cgruber
 * Check in all sources in eclipse-friendly maven-enabled packages.
 *
 * Revision 1.5  2003/08/07 00:15:15  chochos
 * general cleanup (mostly removing unused imports)
 *
 * Revision 1.4  2003/02/28 22:58:57  mpowers
 * Added support for wo-style localization (*.lproj).
 *
 * Revision 1.3  2003/02/21 16:40:24  mpowers
 * Now reading port and smtp host from system properties.
 * Implemented WOApplication.main.
 *
 * Revision 1.2  2003/01/28 19:33:52  mpowers
 * Implemented the rest of WOResourceManager.
 * Implemented support for java-style i18n.
 * Components now use the resource manager to load templates.
 *
 * Revision 1.1  2003/01/27 15:08:00  mpowers
 * Implemented WOResourceManager, using java resources for now.
 *
 *
 */