package com.nuvole.util;

import cn.hutool.core.convert.Convert;

import java.util.*;

/**
 * @author ChenLong
 * @version 1.0
 * @ClassName TreeUtil
 * @Description tree工具类
 * @date 2019/4/23 15:50
 */
public class TreeUtil {

    public static <T> List<Map> convert2Tree(List<T> list) {
        return convert2Tree(list, null, "children");
    }

    public static <T> List<Map> convert2Tree(List<T> list, String childrenKey) {
        return convert2Tree(list, null, childrenKey);
    }

    public static <T> List<Map> convert2Tree(List<T> list, Map<String, String> mapping) {
        return convert2Tree(list, mapping, "children");
    }

    /**
     * 对象数组格式化为tree结构，对象中必须具有{id,pid}属性
     *
     * @param list
     * @param mapping     {"label":"name"} 将数据库查询list中的label属性替换为name属性
     * @param childrenKey 自节点key名称 默认为children
     * @return : java.util.List<java.util.Map>
     * @author ChenLong
     * @date 2019/4/23 18:44
     * @version 1.0
     */
    public static <T> List<Map> convert2Tree(List<T> list, Map<String, String> mapping, String childrenKey) {
        if (list == null || list.size() <= 0) {
            return new ArrayList<Map>();
        }

        Map root = new HashMap();
        root.put(childrenKey, new ArrayList<Map>());

        LinkedHashMap<String, Map> dataSet = new LinkedHashMap<String, Map>();
        for (T obj : list) {
            Map map;
            if (obj instanceof Map) {
                map = new HashMap(){{
                    putAll((Map) obj);
                }};
            } else {
                map = TypeConvertUtil.obj2Map(obj);
            }
            //结果转换
            if (mapping != null) {
                for (String key : mapping.keySet()) {
                    if (map.containsKey(key)) {
                        map.put(mapping.get(key), map.get(key));
                        //移除原有属性
                        map.remove(key);
                    }
                }
            }
            dataSet.put(Convert.toStr(map.get("id")), map);
        }

        //组装树
        for (String key : dataSet.keySet()) {
            Object parentId = ((dataSet.get(key)).get("pid"));
            if(parentId == null){
                /* 增加一种大小写类型
                 * @author dqh
                 * @date  2024-04-12
                 **/
                parentId = ((dataSet.get(key)).get("PId"));
            }
            String pid = Convert.toStr(parentId);
            if (pid.equals("0")) {
                ((List<Map>) root.get(childrenKey)).add((Map) dataSet.get(key));
            } else {
                Map pNode = (Map) dataSet.get(pid);
                if (pNode != null) {
                    if (pNode.get(childrenKey) == null) {
                        List children = new ArrayList<Map>();
                        pNode.put(childrenKey, children);
                    }
                    ((List<Map>) pNode.get(childrenKey)).add((Map) dataSet.get(key));
                } else {
                    ((List<Map>) root.get(childrenKey)).add((Map) dataSet.get(key));
                }
            }
        }

        if (root.get(childrenKey) != null) {
            return (List<Map>) root.get(childrenKey);
        } else {
            return new ArrayList<Map>();
        }

    }

}