package cn.besteam.common.util;

import cn.besteam.modules.system.dto.SysDepartmentDTO;
import cn.hutool.core.collection.CollectionUtil;
import com.google.common.collect.Lists;
import java.util.Iterator;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;

/**
 * @author jie
 * @date 2021/3/9 11:54
 */
public class TreeFilterRegionTreeUtil {


    /**
     * 获取树状结构
     * @param treeList 搜索的树列表
     * @param hitIds 命中的ids
     * @return
     */
    public List<SysDepartmentDTO> searchNode(List<SysDepartmentDTO> treeList, List<Integer> hitIds) {
        List<SysDepartmentDTO> filterTree = Lists.newArrayList();
        for (SysDepartmentDTO t : treeList) {
            SysDepartmentDTO node = filterTree(t, hitIds);
            filterTree.add(node);
        }
        return filterTree.stream().filter(Objects::nonNull).collect(Collectors.toList());
    }

    /**
     * 过滤树
     * @param tree
     * @param hitIds
     * @return
     */
    private SysDepartmentDTO filterTree(SysDepartmentDTO tree, List<Integer> hitIds) {
        /*if(isRemoveNode(tree, hitIds)){
            return null;
        }*/
        Iterator<SysDepartmentDTO> iterator = tree.getChildrenList().iterator();
        while (iterator.hasNext()){
            SysDepartmentDTO child = iterator.next();
            deleteNode(child, iterator, hitIds);
        }
        return tree;
    }

    /**
     * 删除节点
     * @param child
     * @param iterator
     * @param hitIds
     */
    private void deleteNode(SysDepartmentDTO child, Iterator<SysDepartmentDTO> iterator, List<Integer> hitIds) {
        if(isRemoveNode(child, hitIds)){
            iterator.remove();
            return;
        }
        List<SysDepartmentDTO> childrenList = child.getChildrenList();
        if(CollectionUtil.isEmpty(childrenList)){
            return;
        }
        if(hitIds.contains(child.getId())){
            return;
        }
        Iterator<SysDepartmentDTO> children = childrenList.iterator();
        while (children.hasNext()){
            SysDepartmentDTO childChild = children.next();
            deleteNode(childChild,children, hitIds);
        }
    }

    /**
     * 判断该节点是否该删除
     * @param root
     * @param hitIds  命中的节点
     * @return ture 需要删除  false 不能被删除
     */
    private boolean isRemoveNode(SysDepartmentDTO root, List<Integer> hitIds) {
        List<SysDepartmentDTO> children = root.getChildrenList();
        // 叶子节点
        if(CollectionUtil.isEmpty(children)){
            return !hitIds.contains(root.getId());
        }
        // 子节点
        if(hitIds.contains(root.getId())){
            return false;
        }
        boolean bool = true;
        for (SysDepartmentDTO child : children) {
            if(!isRemoveNode(child,hitIds)){
                bool = false;
                break;
            }
        }
        return bool;
    }


}