/**
 * Copyright (c) 2014, the Railo Company Ltd.
 * Copyright (c) 2015, Lucee Assosication Switzerland
 *
 * 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/licenses/>.
 * 
 */
package lucee.runtime.component;

import lucee.runtime.ComponentImpl;
import lucee.runtime.Interface;
import lucee.runtime.InterfaceImpl;
import lucee.runtime.Page;
import lucee.runtime.PageContext;
import lucee.runtime.PageSource;
import lucee.runtime.exp.PageException;
import lucee.runtime.type.util.ArrayUtil;

public class MetadataUtil {

    public static Page getPageWhenMetaDataStillValid(PageContext pc,ComponentImpl comp, boolean ignoreCache) throws PageException {
    	Page page = getPage(pc,comp._getPageSource());
    	if(ignoreCache) return page;

    	if(page.metaData!=null && page.metaData.get()!=null) {
    		if(hasChanged(pc,((MetaDataSoftReference)page.metaData).creationTime,comp)) {
    			page.metaData=null;
    		}
    	}
    	return page;
	}
    public static Page getPageWhenMetaDataStillValid(PageContext pc,InterfaceImpl interf, boolean ignoreCache) throws PageException {
    	Page page = getPage(pc,interf.getPageSource());
    	if(ignoreCache) return page;
    	
    	if(page.metaData!=null && page.metaData.get()!=null) {
    		if(hasChanged(pc,((MetaDataSoftReference)page.metaData).creationTime,interf))
    			page.metaData=null;
    	}
    	return page;
	}
    
	private static boolean hasChanged(PageContext pc,long lastMetaCreation, ComponentImpl component) throws PageException {
		if(component==null) return false;
		
		// check the component
		Page p = getPage(pc, component._getPageSource());
		if(hasChanged(p.getCompileTime(),lastMetaCreation)) return true;
		
		// check interfaces
		Interface[] interfaces = component.getInterfaces();
        if(!ArrayUtil.isEmpty(interfaces)){
        	if(hasChanged(pc,lastMetaCreation,interfaces)) return true;
        }
        
        // check base
		return hasChanged(pc, lastMetaCreation, (ComponentImpl)component.getBaseComponent());
	}
	
	private static boolean hasChanged(PageContext pc,long lastMetaCreation,Interface[] interfaces) throws PageException {
		
		if(!ArrayUtil.isEmpty(interfaces)){
            for(int i=0;i<interfaces.length;i++){
            	if(hasChanged(pc,lastMetaCreation,interfaces[i])) return true;
            }
        }
		return false;
	}

	private static boolean hasChanged(PageContext pc,long lastMetaCreation, Interface inter) throws PageException {
		Page p = getPage(pc, inter.getPageSource());
		if(hasChanged(p.getCompileTime(),lastMetaCreation)) return true;
    	return hasChanged(pc,lastMetaCreation,inter.getExtends());
	}
	

	private static boolean hasChanged(long compileTime, long lastMetaCreation) {
		return compileTime>lastMetaCreation;
	}
	
	private static Page getPage(PageContext pc,PageSource ps) throws PageException {
		/* assuming this code is not necessary, because loadPage also returns the existing page if ok
		Page page = (( PageSourceImpl )ps).getPage();
    	if(page==null) {
    		page = ps.loadPage(pc,false);
    	}
    	return page;*/
		return ps.loadPage(pc,false);
	}
}