package net.sf.dobo.spring;

import net.sf.dobo.Context;
import net.sf.dobo.Dobo;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.FactoryBean;

import java.lang.annotation.Annotation;


/**
 * FactoryBean of Dobo Object
 *
 * @author arif
 * @version 1.0
 */
public class DoboFactoryBean implements FactoryBean, BeanFactoryAware, BeanNameAware {
    /**
     * Context Implementation Object
     */
    private Object contextImplementationObject;

    /**
     * The context
     */
    private Class<?extends Annotation> context;

    /**
     * Flag indicating bean is singleton
     */
    private boolean singleton = false;

    /**
     * The instance of proxy
     */
    private Object instance = null;

    /**
     * Name of the dobo object
     */
    private String name;

    /**
     * Bean factory
     */
    private BeanFactory beanFactory;

    /**
     * @see org.springframework.beans.factory.FactoryBean#getObject()
     */
    public Object getObject() throws Exception {
        synchronized (this) {
            if (singleton && (instance == null)) {
                instance = Dobo.instantiate(contextImplementationObject, context);

                return instance;
            } else {
                return Dobo.instantiate(contextImplementationObject, context);
            }
        }
    }

    /**
     * @see org.springframework.beans.factory.FactoryBean#getObjectType()
     */
    public Class getObjectType() {
        return context.getAnnotation(Context.class).value();
    }

    /**
     * @see org.springframework.beans.factory.FactoryBean#isSingleton()
     */
    public boolean isSingleton() {
        return singleton;
    }

    /**
     * Set to indicate object is singleton
     *
     * @param singleton
     */
    public void setSingleton(final boolean singleton) {
        this.singleton = singleton;
    }

    /**
     * @see org.springframework.beans.factory.BeanFactoryAware#setBeanFactory(org.springframework.beans.factory.BeanFactory)
     */
    public void setBeanFactory(final BeanFactory beanFactory)
        throws BeansException {
        if (contextImplementationObject == null) {
            throw new NullPointerException(
                "Please set \"contextImplementationObject\" property of bean " + name);
        }

        if (context == null) {
            throw new NullPointerException("Please set \"context\" property of bean " + name);
        }

        Dobo.check(contextImplementationObject.getClass());
        this.beanFactory = beanFactory;
    }

    /**
     * @param context
     */
    public void setContext(final Class<?extends Annotation> context) {
        this.context = context;
    }

    /**
     * @param contextImplementationObject
     */
    public void setContextImplementationObject(final Object contextImplementationObject) {
        this.contextImplementationObject = contextImplementationObject;
    }

    /**
     * @see org.springframework.beans.factory.BeanNameAware#setBeanName(java.lang.String)
     */
    public void setBeanName(final String name) {
        this.name = name;
    }
}