package com.kym.jdbc.lambda;


import com.kym.DbUtil;

import java.lang.invoke.SerializedLambda;
import java.lang.reflect.Method;


/**
 * 解析字段列名
 */
public class DefaultLambdaParser {

    public static <T> String getPropertyName(ColumnFunc<T, ?> property) {
        if (property == null) {
            return null;
        }
        try {
            Method declaredMethod = property.getClass().getDeclaredMethod("writeReplace");
            declaredMethod.setAccessible(Boolean.TRUE);
            SerializedLambda serializedLambda = (SerializedLambda) declaredMethod.invoke(property);


//            //Class.method.method....
//            if (serializedLambda.getImplMethodKind() == MethodHandleInfo.REF_invokeStatic) {
//                return getPropertyNameByInvokeStatic(property.getClass().getClassLoader(), serializedLambda);
//            }
            //Class::method
            return getPropertyNameByInvokeVirtual(serializedLambda);

        } catch (ReflectiveOperationException e) {
            throw new RuntimeException(e);
        }
    }

    private static String getPropertyNameByInvokeVirtual(SerializedLambda serializedLambda) {
        String method = serializedLambda.getImplMethodName();

        String attr = null;
        if (method.startsWith("get")) {
            attr = method.substring(3);
        } else {
            attr = method.substring(2);
        }
        return DbUtil.firstToLowerCase(attr);
    }
}