package foundation.data.meta;

import java.util.Date;

import foundation.persist.NamedSQL;
import foundation.persist.SQLRunner;
import foundation.persist.source.NamedDataSource;
import foundation.server.config.ServerStatus;
import foundation.util.Util;

public class MetaMonitor {

	private NamedDataSource dataSource;
	private String dataName;
	private NamedSQL getLastUpdateTimeSQL;
	private Date lastUpdateTime;
	private int count;
	
	public MetaMonitor(String sqlName) {
		this(NamedDataSource.getInstance(), null, sqlName);
		count = 0;
	}
	
	public MetaMonitor(String dataName, String sqlName) {
		this(NamedDataSource.getInstance(), dataName, sqlName);
	}
	
	public MetaMonitor(NamedDataSource dataSource, String dataName, String sqlName) {
		this.dataSource = dataSource;
		this.dataName = dataName;
				
		try {
			getLastUpdateTimeSQL = NamedSQL.getInstance(dataSource.getDBaseType(), sqlName);
			getLastUpdateTimeSQL.setParam("dataName", dataName);
			
			lastUpdateTime = new Date();
			lastUpdateTime.setTime(0);			
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public MetaMonitor(NamedDataSource dataSource, String sqlName) {
		this.dataSource = dataSource;
				
		try {
			getLastUpdateTimeSQL = NamedSQL.getInstance(dataSource.getDBaseType(), sqlName);
			
			lastUpdateTime = new Date();
			lastUpdateTime.setTime(0);			
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public ReloadCheckResult getReloadCheckResult() throws Exception {
		ReloadCheckResult result = new ReloadCheckResult(false, lastUpdateTime);
		
		//1. 如果系统全局设置为不检查，直接退出
		if ((!ServerStatus.isCheckMetaUpdateOnTime()) && count > 1) {
			return result;
		}
		
		//2. 检查是否数据库是否有更新
		Date date = SQLRunner.getDate(dataSource, getLastUpdateTimeSQL);
		
		if (date == null) {
			return result;
		}
		
		boolean changed = (date != null) ? (lastUpdateTime.getTime() < date.getTime()) : true;
		result.setNeedReload(changed); 
		result.setLastUpdateTime(date);
		
		count = count + 1;
		return result;
	}
	
	public ReloadCheckResult getReloadCheckResult(boolean checkMetaUpdate) throws Exception {
		ReloadCheckResult result = new ReloadCheckResult(false, lastUpdateTime);

		Date date = SQLRunner.getDate(dataSource, getLastUpdateTimeSQL);
		
		if (date == null) {
			return result;
		}
		
		boolean changed = (date != null) ? (lastUpdateTime.getTime() < date.getTime()) : true;
		result.setNeedReload(changed); 
		result.setLastUpdateTime(date);
		
		count = count + 1;
		return result;
	}
	
	public Date getLastUpdateTime() {
		return lastUpdateTime;
	}

	public void setLastUpdateTime(Date lastUpdateTime) {
		if (lastUpdateTime == null) {
			return;
		}
		
		this.lastUpdateTime = lastUpdateTime;
	}

	public void setParam(String name, String value) {
		getLastUpdateTimeSQL.setParam(name, value);
	};

	public void setRefreshFlag() {
		lastUpdateTime.setTime(0);
	}

	@Override
	public String toString() {
		String result = dataName + Util.DataTimeToString(lastUpdateTime);
		return result;
	}

}