package com.vincent.rsf.openApi.common.datasource;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.aop.support.AopUtils;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.util.ClassUtils;

import java.lang.reflect.Method;

/**
 * 注解数据源切换
 */
@Aspect
@Component
@Order(Ordered.HIGHEST_PRECEDENCE + 20)
public class UseDataSourceAspect {

    @Around("@annotation(com.vincent.rsf.openApi.common.datasource.UseDataSource) || @within(com.vincent.rsf.openApi.common.datasource.UseDataSource)")
    public Object around(ProceedingJoinPoint joinPoint) throws Throwable {
        UseDataSource useDataSource = resolveAnnotation(joinPoint);
        if (useDataSource == null) {
            return joinPoint.proceed();
        }
        DataSourceContextHolder.push(useDataSource.value());
        try {
            return joinPoint.proceed();
        } finally {
            DataSourceContextHolder.poll();
        }
    }

    private UseDataSource resolveAnnotation(ProceedingJoinPoint joinPoint) {
        Object target = joinPoint.getTarget();
        Class<?> userClass = ClassUtils.getUserClass(target);
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        Method method = signature.getMethod();
        Method specific = AopUtils.getMostSpecificMethod(method, userClass);
        UseDataSource onMethod = AnnotationUtils.findAnnotation(specific, UseDataSource.class);
        if (onMethod != null) {
            return onMethod;
        }
        return AnnotationUtils.findAnnotation(userClass, UseDataSource.class);
    }
}