package com.chinaztt.mes.common.wrapper;

import cn.hutool.core.collection.CollectionUtil;
import lombok.AllArgsConstructor;
import org.apache.ibatis.mapping.ResultMap;
import org.apache.ibatis.mapping.ResultMapping;
import org.apache.ibatis.session.SqlSessionFactory;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

/**
 * @Author: zhangxy
 * @Date: 2020-09-14 10:52
 */
@Component
@AllArgsConstructor
public class ResultMapHelper {

	public final static String CACHE_KEY = "COLUMN_FIELD_MAPS";

	private ApplicationContext applicationContext;

	/**
	 * 获取mybatis所有的field-column映射
	 *
	 * @return
	 */
	@Cacheable(value = CACHE_KEY)
	public Map<Class, Map<String, String>> getColumnMaps() {
		SqlSessionFactory sqlSessionFactory = (SqlSessionFactory) applicationContext.getBean("sqlSessionFactory");
		Collection<ResultMap> resultMaps = sqlSessionFactory.getConfiguration().getResultMaps();
		Map<Class, Map<String, String>> map = new HashMap(1000);
		if (CollectionUtil.isNotEmpty(resultMaps)) {
			for (Object obj : resultMaps) {
				if (!(obj instanceof ResultMap)) {
					continue;
				}
				ResultMap resultMap = (ResultMap) obj;
				Map<String, String> columnFieldMap = new HashMap(50);
				if (resultMap.getResultMappings() != null) {
					for (ResultMapping mapping : resultMap.getResultMappings()) {
						columnFieldMap.put(mapping.getProperty(), mapping.getColumn());
					}
				}
				map.put(resultMap.getType(), columnFieldMap);
			}
		}
		return map;
	}
}