package com.xly.util;


import com.xly.exception.sqlexception.SqlExecuteException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * MySQL SQL执行工具（基于Spring JdbcTemplate）
 */
@Component
public class SqlExecuteUtil {
    private static final Logger log = LoggerFactory.getLogger(SqlExecuteUtil.class);
    @Resource
    private JdbcTemplate jdbcTemplate; // Spring自动注入，无需手动配置

    /**
     * 执行MySQL SELECT语句，返回结构化结果
     * @param sql 已校验的可执行SQL
     * @return List<Map> 保持列顺序
     */
    public List<Map<String, Object>> executeSelectSql(String sql) {
        try {
            log.info("开始执行MySQL SELECT语句：{}", sql);
            // 自定义RowMapper，解析结果集为LinkedHashMap（保持列顺序）
            return jdbcTemplate.query(sql, (RowMapper<Map<String, Object>>) (rs, rowNum) -> {
                Map<String, Object> rowMap = new LinkedHashMap<>();
                ResultSetMetaData metaData = rs.getMetaData();
                int columnCount = metaData.getColumnCount();
                for (int i = 1; i <= columnCount; i++) {
                    rowMap.put(metaData.getColumnName(i), rs.getObject(i));
                }
                return rowMap;
            });
        } catch (Exception e) {
            log.error("MySQL SQL执行失败", e);
            throw new SqlExecuteException("SQL执行失败！错误信息：" + e.getMessage(), e);
        }
    }
}