package com.sandu.ximon.admin.utils;

import com.sandu.common.domain.CommonPage;
import com.sandu.ximon.dao.bo.MonitorBo;
import org.apache.poi.ss.formula.functions.T;

import java.util.ArrayList;
import java.util.List;

/**
 * @author ZZQ
 * @date 2022/4/29 10:47
 */
public class ListPagingUtils {
    public static CommonPage pages(List list, Integer pageNo, Integer pageSize) {
        CommonPage commonPage;

        //开始截断位置
        int fromIndex = (pageNo - 1) * pageSize;
        //结束截断位置
        int toIndex = fromIndex + pageSize;
        //总页数
        int totalPage = (int) Math.ceil(list.size() * 1.0 / pageSize);
        //结束截断位置大于list总长度时，结束截断位置等于list最后一位长度
        if (toIndex > list.size()) {
            toIndex = list.size();
        }

        //查询的页数大于总页数，直接返回空数组
        if (pageNo > totalPage || fromIndex > list.size()) {
            commonPage = CommonPage.restPage(new ArrayList<>());
            commonPage.setTotal(Long.valueOf(list.size()));
            commonPage.setTotalPage(totalPage);
            commonPage.setPageNum(pageNo);
            commonPage.setPageSize(pageSize);
            return commonPage;
        } else {
            commonPage = CommonPage.restPage(list.subList(fromIndex, toIndex));
            commonPage.setTotal(Long.valueOf(list.size()));
            commonPage.setTotalPage(totalPage);
            commonPage.setPageNum(pageNo);
            commonPage.setPageSize(pageSize);
            return commonPage;
        }
    }

}