package com.guo.learningprogresstracker.utils;

import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.Accessors;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * 思维导图树节点 DTO，与 MindMapFileParser 的输出结构兼容。
 * 序列化后可在「nodes」和「children」两个 key 下放置子节点列表。
 *
 * <pre>{@code
 * {
 *   "title": "根标题",
 *   "notes": "备注",
 *   "sourceType": "REPORT",   // 可选：节点来源类型
 *   "sourceId": 1,            // 可选：来源主键
 *   "children": [ ... ]
 * }
 * }</pre>
 */
@Data
@NoArgsConstructor
@AllArgsConstructor
@Accessors(chain = true)
public class MindMapNode {

    private String title;
    private String notes;
    private String sourceType;
    private Integer sourceId;
    private List<MindMapNode> children;

    public MindMapNode(String title) {
        this.title = title;
        this.notes = "";
        this.children = new ArrayList<>();
    }

    /** 构建 JSON 友好的 Map 结构（兼容 MindMapFileParser 输出风格） */
    @SuppressWarnings("unchecked")
    public Map<String, Object> toMap() {
        Map<String, Object> map = new LinkedHashMap<>();
        map.put("title", title != null ? title : "");
        map.put("notes", notes != null ? notes : "");
        if (sourceType != null) map.put("sourceType", sourceType);
        if (sourceId != null) map.put("sourceId", sourceId);
        List<Object> childMaps = new ArrayList<>();
        if (children != null) {
            for (MindMapNode c : children) {
                childMaps.add(c.toMap());
            }
        }
        map.put("children", childMaps);
        return map;
    }

    /** 从 Map 重建节点 */
    public static MindMapNode fromMap(Map<String, Object> map) {
        MindMapNode node = new MindMapNode();
        node.setTitle((String) map.getOrDefault("title", ""));
        node.setNotes((String) map.getOrDefault("notes", ""));
        node.setSourceType((String) map.get("sourceType"));
        if (map.containsKey("sourceId") && map.get("sourceId") != null) {
            node.setSourceId(((Number) map.get("sourceId")).intValue());
        }
        Object raw = map.getOrDefault("children", map.get("nodes"));
        List<MindMapNode> children = new ArrayList<>();
        if (raw instanceof List<?> list) {
            for (Object item : list) {
                if (item instanceof Map<?, ?> m) {
                    children.add(fromMap((Map<String, Object>) m));
                }
            }
        }
        node.setChildren(children);
        return node;
    }

    /** 反序列化 JSON 字符串为 MindMapNode */
    public static MindMapNode fromJson(String json, ObjectMapper mapper) {
        try {
            Map<String, Object> map = mapper.readValue(json, LinkedHashMap.class);
            return fromMap(map);
        } catch (Exception e) {
            return new MindMapNode("解析失败");
        }
    }
}