/*******************************************************************************
 * Copyright (c) 2001, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.wst.internet.cache.internal;

import java.text.MessageFormat;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Preferences;
import org.eclipse.ui.plugin.AbstractUIPlugin;
import org.eclipse.wst.internet.cache.internal.preferences.PreferenceConstants;
import org.osgi.framework.BundleContext;

/**
 * The main plugin class to be used in the desktop.
 */
public class CachePlugin extends AbstractUIPlugin 
{
  /**
   * The ID of this plugin.
   */
  public static final String PLUGIN_ID = "org.eclipse.wst.internet.cache";

  /**
   * The shared instance.
   */
  private static CachePlugin plugin;

  /**
   * The cache job caches resources that were not able to be downloaded when requested.
   */
  private CacheJob job = null;

  /**
   * The constructor.
   */
  public CachePlugin() 
  {
	super();
	plugin = this;
  }

  /**
   * @see org.osgi.framework.BundleActivator#start(org.osgi.framework.BundleContext)
   */
  public void start(BundleContext context) throws Exception 
  {
	super.start(context);
	ToCacheRegistryReader.getInstance().readRegistry();
	Cache.open(Platform.getPluginStateLocation(this));
	if (getPluginPreferences().contains(PreferenceConstants.CACHE_ENABLED)) 
	{
	  setCacheEnabled(getPluginPreferences().getBoolean(PreferenceConstants.CACHE_ENABLED));
	} 
	else 
	{
	  // The cache is disabled by default.
	  setCacheEnabled(false);
	}
	
	// Restore license preferences
	Preferences prefs = getPluginPreferences();
	LicenseRegistry registry = LicenseRegistry.getInstance();
	String[] licenses = registry.getLicenses();
	int numLicenses = licenses.length;
	for(int i = 0; i < numLicenses; i++)
	{
	  int state = prefs.getInt(licenses[i]);
	  if(state == LicenseRegistry.LICENSE_AGREE.intValue())
	  {
		registry.agreeLicense(licenses[i]);
	  }
	  else if(state == LicenseRegistry.LICENSE_DISAGREE.intValue())
	  {
		registry.disagreeLicense(licenses[i]);
	  }
	}
  }

  /**
   * @see org.osgi.framework.BundleActivator#stop(org.osgi.framework.BundleContext)
   */
  public void stop(BundleContext context) throws Exception 
  {
	// Save the license state information.
	Preferences prefs = getPluginPreferences();
	LicenseRegistry registry = LicenseRegistry.getInstance();
	String[] licenses = registry.getLicenses();
	int numLicenses = licenses.length;
	for(int i = 0; i < numLicenses; i++)
	{
	  Integer state = registry.getLicenseState(licenses[i]);
      // For states that have been disagreed to this session store
	  // them as disagree.
	  if(state == LicenseRegistry.LICENSE_DISAGREE_THIS_SESSION)
	  {
		state = LicenseRegistry.LICENSE_DISAGREE;
	  }
	  prefs.setValue(licenses[i], state.intValue());
	}
	
	Cache.getInstance().close();
	stopJob();
	super.stop(context);
	plugin = null;
  }

  /**
   * Returns the shared instance.
   * 
   * @return The shared instance.
   */
  public static CachePlugin getDefault() 
  {
	return plugin;
  }

  /**
   * Returns the string from the plugin's resource bundle, or 'key' if not found.
   * 
   * @param key The key for which the string is requested.
   * @return The string from the plugin's resource bundle, or 'key' if not found.
   */
  public static String getResourceString(String key) 
  {
	ResourceBundle bundle = ResourceBundle
			.getBundle("org.eclipse.wst.internet.cache.internal.CachePluginResources");
	try 
	{
	  return (bundle != null) ? bundle.getString(key) : key;
	} 
	catch (MissingResourceException e) 
	{
	  return key;
	}
  }

  /**
   * Returns the string from the plugin's resource bundle using the specified
   * object, or 'key' if not found.
   * 
   * @param key The key for which the string is requested.
   * @param s1 The object to insert into the string.
   * @return The formatted string.
   */
  public static String getResourceString(String key, Object s1) 
  {
	return MessageFormat.format(getResourceString(key), new Object[] { s1 });
  }

  /**
   * Set whether or not the cache is enabled.
   * 
   * @param enabled If true the cache is enabled, if false it is not enabled.
   */
  public void setCacheEnabled(boolean enabled) 
  {
	getPluginPreferences().setValue(PreferenceConstants.CACHE_ENABLED, enabled);
	if (enabled) 
	{
	  startJob();
	} 
	else 
	{
	  stopJob();
	}
  }

  /**
   * Returns true if the cache is enabled, false otherwise.
   * 
   * @return True if the cache is enabled, false otherwise.
   */
  public boolean isCacheEnabled() 
  {
	if (getPluginPreferences().contains(PreferenceConstants.CACHE_ENABLED))
	  return getPluginPreferences().getBoolean(PreferenceConstants.CACHE_ENABLED);
	return true;
  }
  
  /**
   * Set whether or not the user should be prompted for licenses to which they 
   * have previously disagreed.
   * 
   * @param prompt If true the the user should be prompted, if false the user should not be prompted.
   */
  public void setPromptDisagreedLicenses(boolean prompt) 
  {
	getPluginPreferences().setValue(PreferenceConstants.PROMPT_DISAGREED_LICENSES, prompt);
  }

  /**
   * Returns true if the the user should be prompted for licenses to which they
   * have previously disagreed, false otherwise.
   * 
   * @return True if the user should be prompted, false otherwise.
   */
  public boolean shouldPrompt() 
  {
	if (getPluginPreferences().contains(PreferenceConstants.PROMPT_DISAGREED_LICENSES))
	  return getPluginPreferences().getBoolean(PreferenceConstants.PROMPT_DISAGREED_LICENSES);
	return true;
  }

  /**
   * Start the cache job. The cache job caches resources that were not able to be previously
   * downloaded.
   */
  private void startJob() 
  {
	if (job == null) 
	{
	  job = new CacheJob();
	  job.setPriority(CacheJob.DECORATE);
	  job.schedule(); // start as soon as possible
	}
  }

  /**
   * Stop the cache job. The cache job caches resources that were not able to be previously
   * downloaded.
   */
  private void stopJob() 
  {
	if (job != null) 
	{
	  job.cancel();
	}
	job = null;
  }
}