package com.xcong.farmer.cms.core.handler;

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.xcong.farmer.cms.configurations.properties.CmsProperties;
import com.xcong.farmer.cms.core.node.AttrNode;
import com.xcong.farmer.cms.core.node.Template;
import com.xcong.farmer.cms.core.tag.data.PageChildData;
import com.xcong.farmer.cms.core.tag.data.PageData;
import com.xcong.farmer.cms.core.tag.model.Article;
import com.xcong.farmer.cms.core.tag.model.Column;
import com.xcong.farmer.cms.core.tag.model.Pagination;
import com.xcong.farmer.cms.modules.system.entity.ArticleEntity;
import com.xcong.farmer.cms.modules.system.entity.ColumnEntity;
import com.xcong.farmer.cms.modules.system.mapper.ArticleMapper;
import com.xcong.farmer.cms.modules.system.mapper.ColumnMapper;
import com.xcong.farmer.cms.utils.SpringContextHolder;
import lombok.extern.slf4j.Slf4j;

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

/**
 * @author wzy
 * @date 2022-07-05
 **/
@Slf4j
public class PageDataParserHandler implements DataParserHandler {

    private ArticleMapper articleMapper = SpringContextHolder.getBean(ArticleMapper.class);
    private ColumnMapper columnMapper = SpringContextHolder.getBean(ColumnMapper.class);
    @Override
    public void dataParser(AttrNode attrNode) {
        log.info("分页解析");
        synchronized (this) {
            Template.HAS_PAGING = true;

            String baseUrl = (String) attrNode.getSystemDataValue("baseUrl");

            Long companyId = (Long) attrNode.getSystemDataValue("companyId");
            Pagination param = (Pagination) attrNode.getParam();

            Object pageNum = attrNode.getSystemDataValue("page");
            if (pageNum != null) {
                param.setPage(pageNum.toString());
            }

            Page<ArticleEntity> page = new Page<>(Integer.parseInt(param.getPage()), Integer.parseInt(param.getLimit()));
            ArticleEntity article = new ArticleEntity();
            article.setColumnCode(param.getCode());
            article.setCompanyId(companyId);
            IPage<ArticleEntity> pageList = articleMapper.selectArticleInPage(page, article);

            PageData pageData = new PageData();
            pageData.setTotalPage((int) pageList.getPages());
            pageData.setIndex(Integer.parseInt(param.getPage()));
            pageData.setTotalCnt((int) pageList.getSize());

            if (CollUtil.isNotEmpty(pageList.getRecords())) {
                ColumnEntity parentColumn = columnMapper.selectParentColumnByCodeAndCompanyId(param.getCode(), companyId);
                String path;
                if (parentColumn == null) {
                    path = baseUrl + "/" + param.getCode();
                } else {
                    path = baseUrl + "/" + parentColumn.getColumnCode() + "/" + param.getCode();
                }

                String filename = "index_{}.html";

                List<PageChildData> list = new ArrayList<>();
                int pageNo = Integer.parseInt(param.getPage());

                // 计算出页面显示分页的最大和最小值
                int[] startAndEnd = pageStartAndEnd(pageNo, (int) pageList.getPages(), Integer.parseInt(param.getSize()));
                for (int i = startAndEnd[0]; i <= startAndEnd[1]; i++) {
                    PageChildData child = new PageChildData();
                    child.setIndex(i);
                    if (i == 1) {
                        child.setPath(path + "/index.html");
                    } else {
                        child.setPath(path + "/" + StrUtil.format(filename, i));
                    }
                    list.add(child);
                }

                pageData.setChildren(list);
            } else {
                pageData.setNext("javascript:void(0)");
                pageData.setPrev("javascript:void(0)");
            }

            if (Integer.parseInt(param.getPage()) >= pageList.getPages()) {
                Template.HAS_PAGING = false;
            }

            attrNode.setData(pageData);
        }
    }

    /**
     * (x + y)/2 = index
     * y - x= size  解二元一次方程 x-起点 y-终点
     *
     * @param index 当前页码
     * @param totalPage 总页数
     * @param size 分页大小
     * @return
     */
    public int[] pageStartAndEnd(int index, int totalPage, int size) {
        int[] page = new int[2];
        int end = ((index * 2) + size) / 2;;

        int start = end - size + 1;
        if (start < 1) {
            start = 1;
        }

        if (end > totalPage) {
            end = totalPage;
        }

        page[0] = start;
        page[1] = end;
        return page;
    }

}