/*
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.
 *
 *
 */