package com.imyeyu.config;

import org.yaml.snakeyaml.DumperOptions;
import org.yaml.snakeyaml.introspector.Property;
import org.yaml.snakeyaml.nodes.NodeTuple;
import org.yaml.snakeyaml.nodes.Tag;
import org.yaml.snakeyaml.representer.Representer;

/**
 * 自定义 Representer - SnakeYAML 序列化增强
 * <ul>
 *     <li>跳过 null 值字段，保持 YAML 简洁</li>
 *     <li>禁用类型标签，输出纯净的 YAML</li>
 *     <li>枚举序列化为字符串</li>
 * </ul>
 *
 * @author 夜雨
 * @since 2026-01-12 12:02
 */
public class ConfigRepresenter extends Representer {

	public ConfigRepresenter(DumperOptions options) {
		super(options);
		// null 值表示为空字符串
		this.nullRepresenter = data -> representScalar(Tag.NULL, "");
		// 枚举转字符串（不带类型标签）
		this.representers.put(Enum.class, data -> {
			Enum<?> enumValue = (Enum<?>) data;
			return representScalar(Tag.STR, enumValue.name());
		});
	}

	@Override
	protected NodeTuple representJavaBeanProperty(Object javaBean, Property property, Object propertyValue, Tag customTag) {
		// 跳过 null 值，保持 YAML 简洁
		if (propertyValue == null) {
			return null;
		}
		return super.representJavaBeanProperty(javaBean, property, propertyValue, customTag);
	}

	@Override
	protected org.yaml.snakeyaml.nodes.MappingNode representJavaBean(java.util.Set<Property> properties, Object javaBean) {
		Class<?> clazz = javaBean.getClass();
		// 对于非 Java 标准库的类，使用 MAP 标签而不是类名标签
		if (!clazz.getName().startsWith("java.") && !clazz.getName().startsWith("javax.")) {
			if (this.classTags.get(clazz) == null) {
				this.addClassTag(clazz, Tag.MAP);
			}
		}
		return super.representJavaBean(properties, javaBean);
	}
}