package cn.net.communion.dbdatasync.dbhelper.impl;

import cn.net.communion.dbdatasync.dbhelper.DbHelper;
import cn.net.communion.dbdatasync.entity.JobInfo;
import org.apache.log4j.Logger;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

public class PostgreSql implements DbHelper {
    private Logger logger = Logger.getLogger(PostgreSql.class);

    @Override
    public String assembleSQL(String srcSql, Connection conn, JobInfo jobInfo) throws SQLException {
        String[] fields = jobInfo.getDestTableFields().split(",");
        String destTable = jobInfo.getDestTable();

        PreparedStatement pst = conn.prepareStatement(srcSql);
        ResultSet rs = pst.executeQuery();
        StringBuilder sql = new StringBuilder();
        sql.append("INSERT INTO ").append(destTable).append(" (").append(jobInfo.getDestTableFields()).append(") VALUES ");

        long count = 0;
        while (rs.next()) {
            sql.append("(");
            for (int index = 0; index < fields.length; index++) {
                String value = rs.getString(fields[index]);
                if (value == null) {
                    sql.append("NULL"); // 显式处理 NULL 值
                } else {
                    sql.append("'").append(value).append("'"); // 字符串值加引号
                }
                if (index < fields.length - 1) {
                    sql.append(", ");
                }
            }
            sql.append("),");
            count++;
        }

        if (rs != null) {
            rs.close();
        }
        if (pst != null) {
            pst.close();
        }

        if (count > 0) {
            sql = new StringBuilder(sql.substring(0, sql.length() - 1)); // 删除最后一个逗号
            return sql.toString();
        }
        return null;
    }



    @Override
    public void executeSQL(String sql, Connection conn) throws SQLException {
        logger.debug("Executing SQL: " + sql);
        try (PreparedStatement pst = conn.prepareStatement(sql)) {
            pst.execute();
            conn.commit();
        }
    }

    // 辅助方法：设置参数
    private void setParameters(PreparedStatement pst, List<Object> params) throws SQLException {
        for (int i = 0; i < params.size(); i++) {
            pst.setObject(i + 1, params.get(i));
        }
    }

    // 辅助方法：序列化 SQL 和参数
    private String serializeSqlWithParams(List<String> sqlStatements, List<List<Object>> paramLists) {
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < sqlStatements.size(); i++) {
            result.append(sqlStatements.get(i)).append("; ");
        }
        return result.toString();
    }
}