package com.infoloop.tianting.utils;

import com.infoloop.tianting.model.common.PageResult;

import java.util.LinkedList;
import java.util.List;

public class PageUtil {

    /**
     * 自定义分页
     */
    public static <T> PageResult<T> subListPage(List<T> list, int pageNo, int pageSize) {
        PageResult<T> pageRet = new PageResult<T>();
        //总条数
        int count = list.size();
        pageRet.setTotalCount(count);
        int pages = count % pageSize == 0 ? count / pageSize : (count / pageSize + 1);
        int fromIndex = (pageNo - 1) * pageSize;
        int toIndex = Math.min(pageNo * pageSize, count);
        if (pageNo > pages) {
            pageRet.setDataList(new LinkedList<>());
            pageRet.setPageNo(pageNo);
            pageRet.setPageSize(pageSize);
            pageRet.setTotalPage(pages);
            return pageRet;
        }
        List<T> pageList = list.subList(fromIndex, toIndex);
        pageRet.setDataList(pageList);
        pageRet.setPageNo(pageNo);
        pageRet.setPageSize(pageSize);
        pageRet.setTotalPage(pages);
        return pageRet;
    }

    public static <T> PageResult<T> from(List<T> list, long totalCount, long pages, int pageNo, int pageSize) {
        PageResult<T> pageRet = new PageResult<T>();
        pageRet.setTotalCount(totalCount);
        pageRet.setDataList(list);
        pageRet.setPageNo(pageNo);
        pageRet.setPageSize(pageSize);
        pageRet.setTotalPage(pages);
        return pageRet;
    }
}