package cn.teammodel.service.impl;

import cn.teammodel.model.entity.EvaluationTreeNode;
import cn.teammodel.service.EvaluationTreeService;
import org.apache.commons.lang3.StringUtils;

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

/**
 * @author winter
 * @create 2023-11-20 17:47
 */
public class EvaluationTreeServiceImpl implements EvaluationTreeService {

    @Override
    public List<EvaluationTreeNode> buildTree(List<EvaluationTreeNode> nodes) {
        List<EvaluationTreeNode> parents = new ArrayList<>();
        // pid 为 null 或者 "" 则为 parents
        for (EvaluationTreeNode node : nodes) {
            if (StringUtils.isBlank(node.getPid())) {
                parents.add(node);
            }
        }

        // 迭代构建孩子节点
        for (EvaluationTreeNode parent : parents) {
            buildChildren(parent, nodes);
        }
        return parents;
    }

    /**
     * 递归的构建父亲节点的孩子,以及孩子的孩子 (理论无极树,但应该考虑是否增加递归深度)
     */
    private void buildChildren(EvaluationTreeNode parent, List<EvaluationTreeNode> nodes) {
        List<EvaluationTreeNode> children = getChildren(parent, nodes);
        if (children.size() > 0) return;

        parent.setChildren(children);
        for (EvaluationTreeNode child : children) {
            // 如果子节点还有孩子的话,就继续递归构建
            if (getChildren(child, nodes).size() > 0) {
                buildChildren(child, nodes);
            }
        }

    }

    private List<EvaluationTreeNode> getChildren(EvaluationTreeNode parent, List<EvaluationTreeNode> nodes) {
        List<EvaluationTreeNode> children = new ArrayList<>();
        for (EvaluationTreeNode node : nodes) {
            if (node.getPid().equals(parent.getId())) {
                children.add(node);
            }
        }
        return children;
    }
}