package org.sxkj.common.utils;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;

import java.util.Iterator;
import java.util.Map;

public class CamelKeyToSnakeConverter {
	public static String formatKey(String json) {
		// 原始 JSON 字符串（驼峰命名）

		// 创建 ObjectMapper
		ObjectMapper mapper = new ObjectMapper();

		// 将 JSON 字符串转换为 JsonNode
		JsonNode rootNode = null;
		try {
			rootNode = mapper.readTree(json);
		} catch (JsonProcessingException e) {
			throw new RuntimeException(e);
		}

		// 递归处理 JSON 键
		JsonNode convertedNode = convertKeysToSnakeCase(rootNode);

		// 将转换后的 JsonNode 重新序列化为 JSON 字符串
		String convertedJson = null;
		try {
			convertedJson = mapper.writeValueAsString(convertedNode);
		} catch (JsonProcessingException e) {
			throw new RuntimeException(e);
		}
		System.out.println(convertedJson);
		return convertedJson;
	}

	private static JsonNode convertKeysToSnakeCase(JsonNode node) {
		if (node.isObject()) {
			// 处理 JSON 对象
			ObjectNode objectNode = (ObjectNode) node;
			ObjectNode newObjectNode = objectNode.objectNode();

			Iterator<Map.Entry<String, JsonNode>> fields = objectNode.fields();
			while (fields.hasNext()) {
				Map.Entry<String, JsonNode> field = fields.next();
				String newKey = camelToSnakeCase(field.getKey()); // 转换键
				newObjectNode.set(newKey, convertKeysToSnakeCase(field.getValue())); // 递归处理值
			}

			return newObjectNode;
		} else if (node.isArray()) {
			// 处理 JSON 数组
			ArrayNode arrayNode = (ArrayNode) node;
			ArrayNode newArrayNode = arrayNode.arrayNode();

			for (JsonNode item : arrayNode) {
				newArrayNode.add(convertKeysToSnakeCase(item)); // 递归处理数组中的每个元素
			}

			return newArrayNode;
		}

		// 如果是其他类型（如字符串、数字等），直接返回
		return node;
	}

	private static String camelToSnakeCase(String camelCase) {
		StringBuilder snakeCase = new StringBuilder();
		for (char ch : camelCase.toCharArray()) {
			if (Character.isUpperCase(ch)) {
				snakeCase.append('_').append(Character.toLowerCase(ch));
			} else {
				snakeCase.append(ch);
			}
		}
		return snakeCase.toString();
	}
}