/*******************************************************************************
 * Copyright (c) 2008, 2009 Wind River Systems, Inc. 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:
 *     Markus Schorn - initial API and implementation
 *******************************************************************************/ 
package org.eclipse.cdt.internal.core.pdom.dom.cpp;

import org.eclipse.cdt.core.dom.ast.DOMException;
import org.eclipse.cdt.core.dom.ast.cpp.ICPPTemplateNonTypeParameter;
import org.eclipse.cdt.core.dom.ast.cpp.ICPPTemplateParameter;
import org.eclipse.cdt.core.dom.ast.cpp.ICPPTemplateTemplateParameter;
import org.eclipse.cdt.core.dom.ast.cpp.ICPPTemplateTypeParameter;
import org.eclipse.cdt.internal.core.pdom.PDOM;
import org.eclipse.cdt.internal.core.pdom.db.Database;
import org.eclipse.cdt.internal.core.pdom.dom.PDOMLinkage;
import org.eclipse.cdt.internal.core.pdom.dom.PDOMNode;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;

/**
 * Collects methods to store an argument list in the database.
 */
public class PDOMTemplateParameterArray {
	/**
	 * Stores the given template arguments in the database.
	 * @return the record by which the arguments can be referenced.
	 */
	public static long putArray(final Database db, IPDOMCPPTemplateParameter[] params) throws CoreException {
		final short len= (short) Math.min(params.length, (Database.MAX_MALLOC_SIZE - 2) / 8); 
		final long block= db.malloc(2 + 8 * len);
		long p= block;

		db.putShort(p, len); p += 2;
		for (int i= 0; i < len; i++, p += 4) {
			final IPDOMCPPTemplateParameter elem= params[i];
			db.putRecPtr(p, elem == null ? 0 : elem.getRecord());
		}
		return block;
	}

	/**
	 * Restores an array of template arguments from the database.
	 */
	public static IPDOMCPPTemplateParameter[] getArray(PDOMNode parent, long rec) throws CoreException {
		final PDOM pdom= parent.getPDOM();
		final Database db= pdom.getDB();
		final short len= db.getShort(rec);
		
		Assert.isTrue(len >= 0 && len <= (Database.MAX_MALLOC_SIZE - 2) / 8);
		if (len == 0) {
			return IPDOMCPPTemplateParameter.EMPTY_ARRAY;
		}
		
		rec += 2;
		IPDOMCPPTemplateParameter[] result= new IPDOMCPPTemplateParameter[len];
		for (int i= 0; i < len; i++) {
			final long nodeRec= db.getRecPtr(rec); rec += 4;
			result[i]= nodeRec == 0 ? null : (IPDOMCPPTemplateParameter) PDOMNode.load(pdom, nodeRec);
		}
		return result;
	}
	
	/**
	 * Creates template parameters in the pdom
	 */
	public static IPDOMCPPTemplateParameter[] createPDOMTemplateParameters(PDOMLinkage linkage,
			PDOMNode parent, ICPPTemplateParameter[] origParams) throws CoreException, DOMException {
		IPDOMCPPTemplateParameter[] params= new IPDOMCPPTemplateParameter[origParams.length];
		for (int i = 0; i < origParams.length; i++) {
			params[i]= createPDOMTemplateParameter(linkage, parent, origParams[i]);
		}
		return params;
	}

	/**
	 * Creates a template parameter in the pdom
	 */
	public static IPDOMCPPTemplateParameter createPDOMTemplateParameter(PDOMLinkage linkage,
			PDOMNode parent, ICPPTemplateParameter origParam) throws CoreException, DOMException {
		IPDOMCPPTemplateParameter param= null;
		if (origParam instanceof ICPPTemplateNonTypeParameter) {
			param= new PDOMCPPTemplateNonTypeParameter(linkage, parent, (ICPPTemplateNonTypeParameter) origParam);
		} else if (origParam instanceof ICPPTemplateTypeParameter) {
			param= new PDOMCPPTemplateTypeParameter(linkage, parent, (ICPPTemplateTypeParameter) origParam);
		} else if (origParam instanceof ICPPTemplateTemplateParameter) {
			param= new PDOMCPPTemplateTemplateParameter(linkage, parent, (ICPPTemplateTemplateParameter) origParam);
		}
		return param;
	}
}
