/*******************************************************************************
 * Copyright (c) 2004, 2008 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 - Initial API and implementation
 *******************************************************************************/
package org.eclipse.cdt.internal.core.dom;

import org.eclipse.cdt.core.CCorePlugin;
import org.eclipse.cdt.core.dom.CDOM;
import org.eclipse.cdt.core.dom.ICodeReaderFactory;
import org.eclipse.cdt.core.model.ITranslationUnit;
import org.eclipse.cdt.core.parser.CodeReader;
import org.eclipse.cdt.core.parser.CodeReaderCache;
import org.eclipse.cdt.core.parser.ICodeReaderCache;
import org.eclipse.core.runtime.Preferences;

/**
 * @author jcamelon
 */
public class SavedCodeReaderFactory implements ICodeReaderFactory {

	private ICodeReaderCache cache = null;
	
    public static SavedCodeReaderFactory getInstance()
    {
        return instance;
    }
    
    private static SavedCodeReaderFactory instance = new SavedCodeReaderFactory();
    
    private SavedCodeReaderFactory()
    {
		int size=0;
		Preferences pluginPreferences = CCorePlugin.getDefault().getPluginPreferences();
		if (CCorePlugin.getDefault() == null || pluginPreferences == null)
			size = CodeReaderCache.DEFAULT_CACHE_SIZE_IN_MB;
		else
			size = pluginPreferences.getInt(CodeReaderCache.CODE_READER_BUFFER);
		
		if (size > 0)
			cache = new CodeReaderCache(size);
		else if( size == 0 )
		{
			//necessary for cache to work headless
			String [] properties = pluginPreferences.propertyNames();
			boolean found = false;
			for( int j = 0; j < properties.length; ++j )
				if( properties[j].equals( CodeReaderCache.CODE_READER_BUFFER ) )
				{
					found = true;
					break;
				}
					
			if( !found && size == 0 )
				cache = new CodeReaderCache(CodeReaderCache.DEFAULT_CACHE_SIZE_IN_MB);
            else
                cache = new CodeReaderCache(0);
		}
		else
			cache = new CodeReaderCache(CodeReaderCache.DEFAULT_CACHE_SIZE_IN_MB);
    }
    /* (non-Javadoc)
     * @see org.eclipse.cdt.core.dom.ICodeReaderFactory#getUniqueIdentifier()
     */
    public int getUniqueIdentifier() {
        return CDOM.PARSE_SAVED_RESOURCES;
    }

    /* (non-Javadoc)
     * @see org.eclipse.cdt.core.dom.ICodeReaderFactory#createCodeReaderForTranslationUnit(java.lang.String)
     */
    public CodeReader createCodeReaderForTranslationUnit(String path) {
		return cache.get(path);
    }

    public CodeReader createCodeReaderForTranslationUnit(ITranslationUnit tu) {
		return new CodeReader(tu.getResource().getLocation().toOSString(), tu.getContents());
    }

    /* (non-Javadoc)
     * @see org.eclipse.cdt.core.dom.ICodeReaderFactory#createCodeReaderForInclusion(java.lang.String)
     */
    public CodeReader createCodeReaderForInclusion(String path) {
		return cache.get(path);
    }
	
	/* (non-Javadoc)
     * @see org.eclipse.cdt.core.dom.ICodeReaderFactory#createCodeReaderForInclusion(java.lang.String)
     */
	public ICodeReaderCache getCodeReaderCache() {
		return cache;
	}
}
