package com.product.data.sync.util;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 自定义查询结果
 */
public class CustomResultSet {
    /**
     * 结果集
     */
    private ResultSet resultSet;
    /**
     * 是否自定义结果集
     */
    private boolean isCustom;
    /**
     * next 下表
     */
    private int currentIndex = -1;
    /**
     * 结果集中的列名
     */
    private String[] columnNames;
    /**
     * 自定义结果集时存储每条数据的集合
     */
    private List<Map<String, Object>> values;

    /**
     * 构造函数
     * java.sql.ResultSet
     *
     * @param resultSet
     */
    public CustomResultSet(ResultSet resultSet) {
        this.resultSet = resultSet;
        this.isCustom = false;
    }

    /**
     * 自定义结果集构造
     *
     * @param resultSet
     * @param columnNames
     * @throws SQLException
     */
    public CustomResultSet(ResultSet resultSet, String[] columnNames) throws SQLException {
        this.resultSet = resultSet;
        this.columnNames = columnNames;
        if (this.columnNames == null || this.columnNames.length <= 0) {
            this.columnNames = BatchData.getColumnNames(resultSet);
        }
        this.isCustom = true;
        values = new ArrayList<>();
        while (resultSet.next()) {
            Map<String, Object> value = new HashMap<>();
            for (String columnName : this.columnNames) {
                value.put(columnName, resultSet.getObject(columnName));
            }
            values.add(value);
        }
        this.resultSet.close();
        this.resultSet=null;
    }


    public boolean next() throws SQLException {
        if (isCustom && currentIndex >= 0 && this.values.get(currentIndex) != null) {
            this.values.get(currentIndex).clear();
        }
        currentIndex++;
        return !isCustom ? resultSet.next() : this.values.size() - 1 >= currentIndex;
    }

    public Object getObject(String columnLabel) throws SQLException {
        if (isCustom && this.values.get(this.currentIndex) != null) {
            return this.values.get(this.currentIndex).get(columnLabel);
        } else if (!isCustom) {
            return resultSet.getObject(columnLabel);
        }
        return null;
    }

    public ResultSet getResultSet() {
        return isCustom ? null : resultSet;
    }

    public String[] getColumnNames() {
        return columnNames;
    }
}