package com.smtaiserver.smtaiserver.graph;

import org.springframework.cache.ehcache.EhCacheCacheManager;

import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;

import com.smtaiserver.smtaiserver.core.SMTAIServerApp;
import com.smtaiserver.smtaiserver.database.SMTDatabase;
import com.smtservlet.core.SMTApp;
import com.smtservlet.util.SMTStatic;

public class SMTAIGraphManager 
{
	public static class DBCache
	{
		private SMTDatabase	_db;
		
		public SMTDatabase	allocDatabase() throws Exception
		{
			if(_db == null)
				_db = SMTAIServerApp.getApp().allocDatabase();
			return _db;
		}
		
		public void close()
		{
			if(_db != null)
			{
				_db.close();
				_db = null;
			}
		}
	}
	
	private String			_tableNode = "graph_node";
	private String			_tableLink = "graph_link";
	private Cache			_cacheNode;
	@SuppressWarnings("unused")
	private Cache			_cacheLink;

	
	public SMTAIGraphManager()
	{
		EhCacheCacheManager springCacheManager = SMTApp.getBean(EhCacheCacheManager.class);
		CacheManager cacheManager = springCacheManager.getCacheManager();
		{
			String cacheNodeId = SMTStatic.newUUID();
			cacheManager.addCache(new Cache(cacheNodeId, 10000, false, true, 100, 100));
			_cacheNode = cacheManager.getCache(cacheNodeId);
		}
		{
			String cacheLinkId = SMTStatic.newUUID();
			cacheManager.addCache(new Cache(cacheLinkId, 10000, false, true, 100, 100));
			_cacheLink = cacheManager.getCache(cacheLinkId);
		}
	}

	public void initInstance() throws Exception 
	{

	}
	
	public SMTAIGraphNode getGraphNode(String recId) throws Exception
	{
		DBCache dbCache = new DBCache();
		try
		{
			return getGraphNode(recId, dbCache);
		}
		finally
		{
			dbCache.close();
		}
	}
	
	public SMTAIGraphNode getGraphNode(String recId, DBCache dbCache) throws Exception
	{
		if(recId == null)
			recId = "__GRAPH_ROOT__";
		
		Element element = _cacheNode.get(recId);
		if(element == null)
		{
			_cacheNode.acquireWriteLockOnKey(recId);
			try
			{
				element = _cacheNode.get(recId);
				if(element == null)
				{
					SMTDatabase db = dbCache.allocDatabase();
					SMTAIGraphNode graphNode = new SMTAIGraphNode(this, db, recId, this._tableNode, this._tableLink);
					element = new Element(graphNode.getRecId(), graphNode);
					_cacheNode.put(element);
				}
			}
			finally
			{
				_cacheNode.releaseWriteLockOnKey(recId);
			}
		}
		return (SMTAIGraphNode)element.getObjectValue();
	
	}
}