/*
 * Copyright 2010 the original author or authors.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */ 
package org.springframework.context.groovy;

import groovy.lang.Binding;
import groovy.lang.Closure;
import groovy.lang.GString;
import groovy.lang.GroovyObject;
import groovy.lang.GroovyObjectSupport;
import groovy.lang.GroovyShell;
import groovy.lang.MetaClass;

import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.codehaus.groovy.runtime.DefaultGroovyMethods;
import org.codehaus.groovy.runtime.InvokerHelper;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.RuntimeBeanReference;
import org.springframework.beans.factory.parsing.BeanDefinitionParsingException;
import org.springframework.beans.factory.parsing.EmptyReaderEventListener;
import org.springframework.beans.factory.parsing.FailFastProblemReporter;
import org.springframework.beans.factory.parsing.Location;
import org.springframework.beans.factory.parsing.NullSourceExtractor;
import org.springframework.beans.factory.parsing.Problem;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.ManagedList;
import org.springframework.beans.factory.support.ManagedMap;
import org.springframework.beans.factory.support.SimpleBeanDefinitionRegistry;
import org.springframework.beans.factory.xml.BeanDefinitionParserDelegate;
import org.springframework.beans.factory.xml.DefaultNamespaceHandlerResolver;
import org.springframework.beans.factory.xml.NamespaceHandler;
import org.springframework.beans.factory.xml.NamespaceHandlerResolver;
import org.springframework.beans.factory.xml.ParserContext;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.beans.factory.xml.XmlReaderContext;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.GenericApplicationContext;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.util.Assert;

/**
 * <p>Runtime bean configuration wrapper. Like a Groovy builder, but more of a DSL for
 * Spring configuration. Allows syntax like:</p>
 * 
 * <pre>
 * import org.hibernate.SessionFactory
 * import org.apache.commons.dbcp.BasicDataSource
 * 
 * GroovyBeanDefinitionReader builder = new GroovyBeanDefinitionReader()
 * builder.beans {
 *   dataSource(BasicDataSource) {                  // <--- invokeMethod
 *      driverClassName = "org.hsqldb.jdbcDriver"
 *      url = "jdbc:hsqldb:mem:grailsDB"
 *      username = "sa"                            // <-- setProperty
 *      password = ""
 *      settings = [mynew:"setting"]
 *  } 
 *  sessionFactory(SessionFactory) {
 *  	   dataSource = dataSource                 // <-- getProperty for retrieving refs
 *  }
 *  myService(MyService) {
 *      nestedBean = { AnotherBean bean->          // <-- setProperty with closure for nested bean
 *      		dataSource = dataSource
 *      }
 *  }
 * }
 * </pre>
 * <p>
 *   You can also use the Spring IO API to load resources containing beans defined as a Groovy
 *   script using either the constructors or the loadBeans(Resource[] resources) method
 * </p>
 * 
 */
public class GroovyBeanDefinitionReader extends GroovyObjectSupport {
	private static final Log LOG = LogFactory.getLog(GroovyBeanDefinitionReader.class);
	private static final String CREATE_APPCTX = "createApplicationContext";
    private static final String REGISTER_BEANS = "registerBeans";
    private static final String BEANS = "beans";
    private static final String REF = "ref";
    private RuntimeSpringConfiguration springConfig;
    private BeanConfiguration currentBeanConfig;
    private Map<String, DeferredProperty> deferredProperties = new HashMap<String, DeferredProperty>();
    private ApplicationContext parentCtx;
    private Map binding = Collections.EMPTY_MAP;
    private ClassLoader classLoader = null;
    private NamespaceHandlerResolver namespaceHandlerResolver;
    private Map<String, NamespaceHandler> namespaceHandlers = new HashMap<String, NamespaceHandler>();
    private XmlBeanDefinitionReader xmlBeanDefinitionReader;
    private Map<String, String> namespaces = new HashMap<String, String>();
    private Resource beanBuildResource = new ByteArrayResource(new byte[0]);
    private XmlReaderContext readerContext;
    private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();

    public GroovyBeanDefinitionReader() {
		this(null,null);
	}
    
    public GroovyBeanDefinitionReader(ClassLoader classLoader) {
		this(null, classLoader);
	}    
	
	public GroovyBeanDefinitionReader(ApplicationContext parent) {
        this(parent, null);
	}	
	
	public GroovyBeanDefinitionReader(ApplicationContext parent,ClassLoader classLoader) {
        this(parent,null, classLoader);

    }

    public GroovyBeanDefinitionReader(ApplicationContext parentCtx, RuntimeSpringConfiguration springConfig,  ClassLoader classLoader) {
        this.springConfig = springConfig == null ? createRuntimeSpringConfiguration(parentCtx, classLoader) : springConfig;
        this.parentCtx = parentCtx;
        this.classLoader = classLoader;
        initializeSpringConfig();
    }

    public void setResourcePatternResolver(ResourcePatternResolver resourcePatternResolver) {
    	Assert.notNull(resourcePatternResolver, "The argument [resourcePatternResolver] cannot be null");
		this.resourcePatternResolver = resourcePatternResolver;
	}


	protected void initializeSpringConfig() {
        this.xmlBeanDefinitionReader = new XmlBeanDefinitionReader((GenericApplicationContext)springConfig.getUnrefreshedApplicationContext());
        initializeGroovyBeanDefinitionReaderForClassLoader(this.classLoader);        
    }

    public void setClassLoader(ClassLoader classLoader) {
        this.classLoader = classLoader == null ? getClass().getClassLoader() : classLoader;
        initializeGroovyBeanDefinitionReaderForClassLoader(classLoader);

    }

    protected void initializeGroovyBeanDefinitionReaderForClassLoader(ClassLoader classLoader) {
        xmlBeanDefinitionReader.setBeanClassLoader(classLoader);
        this.namespaceHandlerResolver = new DefaultNamespaceHandlerResolver(this.classLoader);
        this.readerContext = new XmlReaderContext(beanBuildResource,new FailFastProblemReporter(),new EmptyReaderEventListener(),new NullSourceExtractor(),xmlBeanDefinitionReader,namespaceHandlerResolver);
    }

    public void setNamespaceHandlerResolver(NamespaceHandlerResolver namespaceHandlerResolver) {
        this.namespaceHandlerResolver = namespaceHandlerResolver;
    }

    protected RuntimeSpringConfiguration createRuntimeSpringConfiguration(ApplicationContext parent, ClassLoader classLoader) {
        return new DefaultRuntimeSpringConfiguration(parent, classLoader);
    }

    public Log getLog() {
		return LOG;
	}

    
    /**
     * Imports Spring bean definitions from either XML or Groovy sources into the current bean builder instance
     * 
     * @param resourcePattern The resource pattern
     */
    public void importBeans(String resourcePattern) {
    	try {
			Resource[] resources =resourcePatternResolver.getResources(resourcePattern);
			for (int i = 0; i < resources.length; i++) {
				Resource resource = resources[i];
				if(resource.getFilename().endsWith(".groovy")) {
					loadBeans(resource);
				}
				else if(resource.getFilename().endsWith(".xml")) {
					SimpleBeanDefinitionRegistry beanRegistry = new SimpleBeanDefinitionRegistry();
					XmlBeanDefinitionReader beanReader = new XmlBeanDefinitionReader(beanRegistry);
					beanReader.loadBeanDefinitions(resource);
					String[] beanNames = beanRegistry.getBeanDefinitionNames();
					for (int j = 0; j < beanNames.length; j++) {
						String beanName = beanNames[j];
						springConfig.addBeanDefinition(beanName, beanRegistry.getBeanDefinition(beanName));
					}
				}
			}
			
		} catch (IOException e) {
			LOG.error("Error loading beans for resource pattern: " + resourcePattern, e);
		}
    }
    
    /**
     * Defines an Spring namespace definition to use
     *
     * @param definition The definition
     */
    public void xmlns(Map<String, String> definition) {
        Assert.notNull(namespaceHandlerResolver, "You cannot define a Spring namespace without a [namespaceHandlerResolver] set");
        if(!definition.isEmpty()) {


            for(Map.Entry<String,String> entry : definition.entrySet()) {
                String namespace = entry.getKey();
                String uri = null;
                if(entry.getValue() != null) {
                    uri = entry.getValue();
                }

                if(uri==null) {
                    throw new IllegalArgumentException("Namespace definition cannot supply a null URI");
                }
                final NamespaceHandler namespaceHandler = namespaceHandlerResolver.resolve(uri);
                if(namespaceHandler == null) {
                    throw new BeanDefinitionParsingException(new Problem("No namespace handler found for URI: " + uri, new Location(this.readerContext.getResource())));
                }
                namespaceHandlers.put(namespace, namespaceHandler);
                namespaces.put(namespace, uri);

            }

        }
    }

	/**
	 * Retrieves the parent ApplicationContext
	 * @return The parent ApplicationContext
	 */
	public ApplicationContext getParentCtx() {
		return parentCtx;
	}

	/**
	 * Retrieves the RuntimeSpringConfiguration instance used the the GroovyBeanDefinitionReader
	 * @return The RuntimeSpringConfiguration instance
	 */
	public RuntimeSpringConfiguration getSpringConfig() {
		return springConfig;
	}

	/**
	 * Retrieves a BeanDefinition for the given name
	 * @param name The bean definition
	 * @return The BeanDefinition instance
	 */
	public BeanDefinition getBeanDefinition(String name) {
		if(!getSpringConfig().containsBean(name))
			return null;
		return getSpringConfig().getBeanConfig(name).getBeanDefinition();
	}

    /**
     * Retrieves all BeanDefinitions for this GroovyBeanDefinitionReader
     *
     * @return A map of BeanDefinition instances with the bean id as the key
     */
    public Map<String, BeanDefinition> getBeanDefinitions() {

        Map<String, BeanDefinition> beanDefinitions = new HashMap<String, BeanDefinition>();
        final List beanNames = getSpringConfig().getBeanNames();
        for (Object beanName1 : beanNames) {
            String beanName = (String) beanName1;
            BeanDefinition bd = getSpringConfig()
                    .getBeanConfig(beanName)
                    .getBeanDefinition();
            beanDefinitions.put(beanName, bd);
        }
        return beanDefinitions;
    }

    /**
	 * Sets the runtime Spring configuration instance to use. This is not necessary to set
	 * and is configured to default value if not, but is useful for integrating with other
	 * spring configuration mechanisms @see org.codehaus.groovy.grails.commons.spring.GrailsRuntimeConfigurator
	 * 
	 * @param springConfig The spring config
	 */
	public void setSpringConfig(RuntimeSpringConfiguration springConfig) {
		this.springConfig = springConfig;
        initializeSpringConfig();
	}

	/**
	 * This class is used to defer the adding of a property to a bean definition until later
	 * This is for a case where you assign a property to a list that may not contain bean references at
	 * that point of asignment, but may later hence it would need to be managed
	 * 
	 * @author Graeme Rocher
	 */
	private class DeferredProperty {
		private BeanConfiguration config;
		private String name;
		private Object value;

		DeferredProperty(BeanConfiguration config, String name, Object value) {
			this.config = config;
			this.name = name;
			this.value = value;
		}

		public void setInBeanConfig() {
			this.config.addProperty(name, value);
		}
	}
	
	/**
	 * A RuntimeBeanReference that takes care of adding new properties to runtime references
	 * 
	 * @author Graeme Rocher
	 * @since 0.4
	 *
	 */
	private class ConfigurableRuntimeBeanReference extends RuntimeBeanReference implements GroovyObject {

		private MetaClass metaClass;
		private BeanConfiguration beanConfig;

		public ConfigurableRuntimeBeanReference(String beanName, BeanConfiguration beanConfig) {
			this(beanName, beanConfig, false);			
		}

		public ConfigurableRuntimeBeanReference(String beanName, BeanConfiguration beanConfig, boolean toParent) {
			super(beanName, toParent);
			this.beanConfig = beanConfig;
			if(beanConfig == null)
				throw new IllegalArgumentException("Argument [beanConfig] cannot be null");
			this.metaClass = InvokerHelper.getMetaClass(this);
		}

		public MetaClass getMetaClass() {
			return this.metaClass;
		}

		public Object getProperty(String property) {
			if(property.equals("beanName"))
				return getBeanName();
			else if(property.equals("source"))
				return getSource();
			else if(this.beanConfig != null) {
				return new WrappedPropertyValue(property,beanConfig.getPropertyValue(property));
			}				
			else
				return this.metaClass.getProperty(this, property);
		}



        /**
		 * Wraps a BeanConfiguration property an ensures that any RuntimeReference additions to it are
		 * deferred for resolution later
		 *  
		 * @author Graeme Rocher
		 * @since 0.4
		 *
		 */
		private class WrappedPropertyValue extends GroovyObjectSupport {
			private Object propertyValue;
			private String propertyName;
			public WrappedPropertyValue(String propertyName, Object propertyValue) {
				this.propertyValue = propertyValue;
				this.propertyName = propertyName;
			}

			public void leftShift(Object value) {
				InvokerHelper.invokeMethod(propertyValue, "leftShift", value);
                updateDeferredProperties(value);
			}

            public boolean add(Object value) {
                boolean retval = (Boolean) InvokerHelper.invokeMethod(propertyValue, "add", value);
                updateDeferredProperties(value);
                return retval;
            }

            public boolean addAll(Collection values) {
                boolean retval = (Boolean) InvokerHelper.invokeMethod(propertyValue, "addAll", values);
                for (Object value : values) {
                    updateDeferredProperties(value);
                }
                return retval;
            }

            public Object invokeMethod(String name, Object args) {
                return InvokerHelper.invokeMethod(propertyValue, name, args);
            }

            public Object getProperty(String name) {
                return InvokerHelper.getProperty(propertyValue, name);
            }

            public void setProperty(String name, Object value) {
                InvokerHelper.setProperty(propertyValue, name, value);
            }

            private void updateDeferredProperties(Object value) {
                if (value instanceof RuntimeBeanReference) {
                    deferredProperties.put(beanConfig.getName(), new DeferredProperty(beanConfig, propertyName, propertyValue));
                }
            }
		}
		public Object invokeMethod(String name, Object args) {
			return this.metaClass.invokeMethod(this, name, args);
		}

		public void setMetaClass(MetaClass metaClass) {
			this.metaClass = metaClass;
		}

		public void setProperty(String property, Object newValue) {
            if(!addToDeferred(beanConfig,property, newValue)) {
                beanConfig.setPropertyValue(property, newValue);
            }
		}
	}	
	/**
	 * Takes a resource pattern as (@see org.springframework.core.io.support.PathMatchingResourcePatternResolver)
	 * This allows you load multiple bean resources in this single builder
	 * 
	 * eg loadBeans("classpath:*Beans.groovy")
	 *  
	 * @param resourcePattern The resource pattern
	 * @throws IOException When the path cannot be matched
	 */	
	public void loadBeans(String resourcePattern) throws IOException {
		loadBeans(new PathMatchingResourcePatternResolver().getResources(resourcePattern));
	}
	
	/**
	 * Loads a single Resource into the bean builder
	 * 
	 * @param resource The resource to load
	 * @throws IOException When an error occurs
	 */
	public void loadBeans(Resource resource) throws IOException {
        this.beanBuildResource = resource;
		loadBeans(new Resource[]{resource});
	}	
	
	/**
	 * Loads a set of given beans
	 * @param resources The resources to load
	 * @throws IOException Thrown if there is an error reading one of the passes resources
	 */
	public void loadBeans(Resource[] resources) throws IOException {
		Closure beans = new Closure(this){
			public Object call(Object[] args) {
				invokeBeanDefiningClosure((Closure)args[0]);
				return null;
			}			
		};
		Binding b = new Binding() {
            @Override
            public void setVariable(String name, Object value) {
                if(currentBeanConfig!=null) {
                    setPropertyOnBeanConfig(name, value);
                }
                else {
                    super.setVariable(name, value);    
                }
            }
        };
		b.setVariable("beans", beans);


        for (Resource resource : resources) {
            try {
                GroovyShell shell = classLoader != null ? new GroovyShell(classLoader, b) : new GroovyShell(b);
                shell.evaluate(resource.getInputStream());
            }
            catch (Throwable e) {
                throw new BeanDefinitionParsingException(new Problem("Error evaluating bean definition script: " + e.getMessage(), new Location(resource), null, e));
            }
        }
	}

    /**
     * Register a set of beans with the given bean registry. Most
     * application contexts are bean registries.
     */
    public void registerBeans(BeanDefinitionRegistry registry) {
        finalizeDeferredProperties();

        if (registry instanceof GenericApplicationContext) {
            GenericApplicationContext ctx = (GenericApplicationContext) registry;
            ctx.setClassLoader(this.classLoader);
            ctx.getBeanFactory().setBeanClassLoader(this.classLoader);
        }

        springConfig.registerBeansWithRegistry(registry);
    }


    /**
     * Registers bean definitions with another instance of RuntimeSpringConfiguration, overriding any beans in the target.
     *
     * @param targetSpringConfig The RuntimeSpringConfiguration object
     */
    public void registerBeans(RuntimeSpringConfiguration targetSpringConfig) {
         this.springConfig.registerBeansWithConfig(targetSpringConfig);
    }

    /**
	 * This method overrides method invocation to create beans for each method name that
	 * takes a class argument
	 */
	public Object invokeMethod(String name, Object arg) {
        Object[] args = (Object[])arg;
        
        if(CREATE_APPCTX.equals(name)) {
            return createApplicationContext();
		}
        else if(REGISTER_BEANS.equals(name) && args.length == 1 && args[0] instanceof GenericApplicationContext) {
            registerBeans((GenericApplicationContext)args[0]);
            return null;
        }
        else if(BEANS.equals(name) && args.length == 1 && args[0] instanceof Closure) {
            return beans((Closure)args[0]);
        }
		else if(REF.equals(name)) {
			String refName;
			if(args[0] == null)
				throw new IllegalArgumentException("Argument to ref() is not a valid bean or was not found");
			
			if(args[0] instanceof RuntimeBeanReference) {
				refName = ((RuntimeBeanReference)args[0]).getBeanName();
			}
			else {
				refName = args[0].toString();	
			}
			
			boolean parentRef = false;
			if(args.length > 1) {
				if(args[1] instanceof Boolean) {
					parentRef = (Boolean) args[1];
				}
			}
			return new RuntimeBeanReference(refName, parentRef);
		}
        else if(namespaceHandlers.containsKey(name) && args.length > 0 && (args[0] instanceof Closure)) {
            DynamicElementReader reader = createDynamicElementReader(name, true);
            reader.invokeMethod("doCall",args);
        }
		else if(args.length > 0 && args[0] instanceof Closure) {
            // abstract bean definition
            return invokeBeanDefiningMethod(name, args);
		}
		else if(args.length > 0 && args[0] instanceof Class || args.length > 0 && args[0] instanceof RuntimeBeanReference || args.length > 0 &&args[0] instanceof Map) {
			return invokeBeanDefiningMethod(name, args);			
		}
		else if (args.length > 1 && args[args.length -1] instanceof Closure) {
			return invokeBeanDefiningMethod(name, args);
		}
        ApplicationContext ctx = springConfig.getUnrefreshedApplicationContext();
        MetaClass mc = DefaultGroovyMethods.getMetaClass(ctx);
        if(!mc.respondsTo(ctx, name, args).isEmpty()){
            return mc.invokeMethod(ctx,name, args);
        }
        
        return this;
	}



    /**
     * Defines a set of beans for the given block or closure.
     *
     * @param c The block or closure
     * @return This GroovyBeanDefinitionReader instance
     */
    public GroovyBeanDefinitionReader beans(Closure c) {
        return invokeBeanDefiningClosure(c);
    }

    /**
     * Creates an ApplicationContext from the current state of the GroovyBeanDefinitionReader
     * @return The ApplicationContext instance
     */
    public ApplicationContext createApplicationContext() {
        finalizeDeferredProperties();
        return springConfig.getApplicationContext();
    }

    protected void finalizeDeferredProperties() {
        for (Object o : deferredProperties.values()) {
            DeferredProperty dp = (DeferredProperty) o;

            if (dp.value instanceof List) {
                dp.value = manageListIfNecessary(dp.value);
            }
            else if (dp.value instanceof Map) {
                dp.value = manageMapIfNecessary(dp.value);
            }
            dp.setInBeanConfig();
        }
		deferredProperties.clear();
	}
	
	protected boolean addToDeferred(BeanConfiguration beanConfig,String property, Object newValue) {
		if(newValue instanceof List) {
			deferredProperties.put(currentBeanConfig.getName()+property,new DeferredProperty(currentBeanConfig, property, newValue));
			return true;
		}
		else if(newValue instanceof Map) {
			deferredProperties.put(currentBeanConfig.getName()+property,new DeferredProperty(currentBeanConfig, property, newValue));
			return true;
		}
		return false;
	}
	/**
	 * This method is called when a bean definition node is called
	 * 
	 * @param name The name of the bean to define
	 * @param args The arguments to the bean. The first argument is the class name, the last argument is sometimes a closure. All
	 * the arguments in between are constructor arguments
	 * @return The bean configuration instance
	 */
	protected BeanConfiguration invokeBeanDefiningMethod(String name, Object[] args) {

        boolean hasClosureArgument = args[args.length - 1] instanceof Closure;
        if(args[0] instanceof Class) {
            Class beanClass = args[0] instanceof Class ? (Class)args[0] : args[0].getClass();

            if(args.length >= 1) {
                if(hasClosureArgument) {
					if(args.length-1 != 1) {
                        currentBeanConfig = springConfig.addSingletonBean(name, beanClass, resolveConstructorArguments(args,1,args.length-1));
					}
					else {
						currentBeanConfig = springConfig.addSingletonBean(name, beanClass);
					}				
				}
				else  {
                    currentBeanConfig = springConfig.addSingletonBean(name, beanClass, resolveConstructorArguments(args,1,args.length));
				}

			}			
		}
		else if(args[0] instanceof RuntimeBeanReference) {
			currentBeanConfig = springConfig.addSingletonBean(name);
			currentBeanConfig.setFactoryBean(((RuntimeBeanReference)args[0]).getBeanName());
		}
		else if(args[0] instanceof Map) {
            // named constructor arguments
            if(args.length > 1 && args[1] instanceof Class) {
                List constructorArgs = resolveConstructorArguments(args, 2, hasClosureArgument ? args.length-1 :  args.length);
                currentBeanConfig = springConfig.addSingletonBean(name, (Class)args[1], constructorArgs);

                Map namedArgs = (Map)args[0];
                for (Object o : namedArgs.keySet()) {
                    String propName = (String) o;
                    setProperty(propName, namedArgs.get(propName));
                }
            }
            // factory method syntax
            else {
                currentBeanConfig = springConfig.addSingletonBean(name);
                //First arg is the map containing factoryBean : factoryMethod
                Map.Entry factoryBeanEntry = (Map.Entry)((Map)args[0]).entrySet().iterator().next();
                // If we have a closure body, that will be the last argument.
                // In between are the constructor args
                int constructorArgsTest = hasClosureArgument?2:1;
                // If we have more than this number of args, we have constructor args
                if(args.length > constructorArgsTest){
                    //factory-method requires args
                    int endOfConstructArgs = hasClosureArgument? args.length-1 : args.length;
                    currentBeanConfig = springConfig.addSingletonBean(name, null, resolveConstructorArguments(args, 1, endOfConstructArgs));
                } else {
                    currentBeanConfig = springConfig.addSingletonBean(name);
                }
                currentBeanConfig.setFactoryBean(factoryBeanEntry.getKey().toString());
                currentBeanConfig.setFactoryMethod(factoryBeanEntry.getValue().toString());
            }

        }
        else if(args[0] instanceof Closure) {
            currentBeanConfig = springConfig.addAbstractBean(name);
        }
        else {
            List constructorArgs = resolveConstructorArguments(args, 0, hasClosureArgument ? args.length-1 : args.length);
            currentBeanConfig = new DefaultBeanConfiguration(name, null, constructorArgs);
            springConfig.addBeanConfiguration(name,currentBeanConfig);
        }


        if(hasClosureArgument) {
			Closure callable = (Closure)args[args.length-1];
			callable.setDelegate(this);
            callable.setResolveStrategy(Closure.DELEGATE_FIRST);
            callable.call(new Object[]{currentBeanConfig});
							
		}

        BeanConfiguration beanConfig = currentBeanConfig;
        currentBeanConfig = null;
		return beanConfig;
	}

    protected List resolveConstructorArguments(Object[] args, int start, int end) {
        Object[] constructorArgs = subarray(args, start, end);
        filterGStringReferences(constructorArgs);
        for(int i = 0; i < constructorArgs.length; i++) {
        	if(constructorArgs[i] instanceof List) {
        		constructorArgs[i] = manageListIfNecessary(constructorArgs[i]);
        	} else if(constructorArgs[i] instanceof Map){
        		constructorArgs[i] = manageMapIfNecessary(constructorArgs[i]);
        	}
        }
        List constructorArgsList = Arrays.asList(constructorArgs);
        return constructorArgsList;
    }

    protected Object[] subarray(Object[] args, int i, int j) {
        if(j > args.length) throw new IllegalArgumentException("Upper bound can't be greater than array length");
        Object[] b = new Object[j-i];
        int n = 0;
        for (int k = i;  k < j; k++,n++) {
            b[n] = args[k];
            
        }
        return b;
    }

    protected void filterGStringReferences(Object[] constructorArgs) {
        for (int i = 0; i < constructorArgs.length; i++) {
            Object constructorArg = constructorArgs[i];
            if(constructorArg instanceof GString) constructorArgs[i] = constructorArg.toString();
        }
    }

    /**
	 * When an methods argument is only a closure it is a set of bean definitions
	 * 
	 * @param callable The closure argument
     * @return This GroovyBeanDefinitionReader instance
	 */
	protected GroovyBeanDefinitionReader invokeBeanDefiningClosure(Closure callable) {

		callable.setDelegate(this);
  //      callable.setResolveStrategy(Closure.DELEGATE_FIRST);
        callable.call();
		finalizeDeferredProperties();

        return this;
    }

	/**
	 * This method overrides property setting in the scope of the GroovyBeanDefinitionReader to set
	 * properties on the current BeanConfiguration
	 */
	public void setProperty(String name, Object value) {
		if(currentBeanConfig != null) {
            setPropertyOnBeanConfig(name, value);
		}		
	}

    /**
     * Defines an inner bean definition
     *
     * @param type The bean type
     * @return The bean definition
     */
    public AbstractBeanDefinition bean(Class type) {
        return springConfig.createSingletonBean(type).getBeanDefinition();
    }

    /**
     * Defines an inner bean definition
     *
     * @param type The bean type
     * @param args The constructors arguments and closure configurer
     * @return The bean definition
     */
    public AbstractBeanDefinition bean(Class type, Object...args) {
        BeanConfiguration current = currentBeanConfig;
        try {

            Closure callable = null;
            Collection constructorArgs = null;
            if(args != null && args.length > 0) {
                int index = args.length;
                Object lastArg = args[index-1];

                if(lastArg instanceof Closure) {
                    callable = (Closure) lastArg;
                    index--;
                }
                if(index > -1) {
                    constructorArgs = resolveConstructorArguments(args, 0, index);
                }
            }
            currentBeanConfig =  constructorArgs != null ? springConfig.createSingletonBean(type,constructorArgs) : springConfig.createSingletonBean(type);
            if(callable != null) {
                callable.call(new Object[]{currentBeanConfig});
            }
            return currentBeanConfig.getBeanDefinition();

        }
        finally {
            currentBeanConfig = current;
        }
    }
    
    protected void setPropertyOnBeanConfig(String name, Object value) {
        if(value instanceof GString)value = value.toString();
        if(addToDeferred(currentBeanConfig, name, value)) {
            return;
        }
        else if(value instanceof Closure) {
            BeanConfiguration current = currentBeanConfig;
            try {
                Closure callable = (Closure)value;

                Class parameterType = callable.getParameterTypes()[0];
                if(parameterType.equals(Object.class)) {
                    currentBeanConfig = springConfig.createSingletonBean("");
                    callable.call(new Object[]{currentBeanConfig});
                }
                else {
                    currentBeanConfig = springConfig.createSingletonBean(parameterType);
                    callable.call(null);
                }

                value = currentBeanConfig.getBeanDefinition();
            }
            finally {
                currentBeanConfig = current;
            }
        }
        currentBeanConfig.addProperty(name, value);
    }

    /**
	 * Checks whether there are any runtime refs inside a Map and converts
	 * it to a ManagedMap if necessary
	 * 
	 * @param value The current map
	 * @return A ManagedMap or a normal map
	 */
	protected Object manageMapIfNecessary(Object value) {
		Map map = (Map)value;
		boolean containsRuntimeRefs = false;
        for (Object e : map.values()) {
            if (e instanceof RuntimeBeanReference) {
                containsRuntimeRefs = true;
                break;
            }
        }
		if(containsRuntimeRefs) {
            Map managedMap = new ManagedMap();
            managedMap.putAll(map);
            return managedMap; 
		}
		return value;
	}

	/**
	 * Checks whether there are any runtime refs inside the list and 
	 * converts it to a ManagedList if necessary
	 * 
	 * @param value The object that represents the list
	 * @return Either a new list or a managed one
	 */
	protected Object manageListIfNecessary(Object value) {
		List list = (List)value;
		boolean containsRuntimeRefs = false;
        for (Object e : list) {
            if (e instanceof RuntimeBeanReference) {
                containsRuntimeRefs = true;
                break;
            }
        }
		if(containsRuntimeRefs) {
			List tmp = new ManagedList();
			tmp.addAll((List)value);
			value = tmp;					
		}
		return value;
	}

	/**
	 * This method overrides property retrieval in the scope of the GroovyBeanDefinitionReader to either:
	 * 
	 * a) Retrieve a variable from the bean builder's binding if it exists
	 * b) Retrieve a RuntimeBeanReference for a specific bean if it exists
	 * c) Otherwise just delegate to super.getProperty which will resolve properties from the GroovyBeanDefinitionReader itself
	 */
	public Object getProperty(String name) {

		if(binding.containsKey(name)) {
			return binding.get(name);
		}
		else {
            if(namespaceHandlers.containsKey(name)) {
                return createDynamicElementReader(name, currentBeanConfig!=null);

            }
			if(springConfig.containsBean(name)) {
				BeanConfiguration beanConfig = springConfig.getBeanConfig(name);
				if(beanConfig != null) {
					return new ConfigurableRuntimeBeanReference(name, springConfig.getBeanConfig(name) ,false);
				}					
				else
					return new RuntimeBeanReference(name,false);
			}
			// this is to deal with the case where the property setter is the last
			// statement in a closure (hence the return value)
			else if(currentBeanConfig != null) {
				if(currentBeanConfig.hasProperty(name))
					return currentBeanConfig.getPropertyValue(name);
				else {
					DeferredProperty dp = deferredProperties.get(currentBeanConfig.getName()+name);
					if(dp!=null) {
						return dp.value;
					}
					else {
						return super.getProperty(name);
					}
				}
			}
			else {
				return super.getProperty(name);
			}			
		}			
	}

    protected DynamicElementReader createDynamicElementReader(String namespace, final boolean decorator) {
        NamespaceHandler handler = namespaceHandlers.get(namespace);
        ParserContext parserContext = new ParserContext(readerContext, new BeanDefinitionParserDelegate(readerContext));
        final DynamicElementReader dynamicElementReader = new DynamicElementReader(namespace, this.namespaces, handler, parserContext) {
            @Override
            protected void afterInvocation() {
                if(!decorator) {
                    currentBeanConfig = null;
                }
            }
        };
        dynamicElementReader.setClassLoader(classLoader);
        if(currentBeanConfig!=null) {
            dynamicElementReader.setBeanConfiguration(currentBeanConfig);
        }
        else if(!decorator) {
            currentBeanConfig = new DefaultBeanConfiguration(namespace);
            dynamicElementReader.setBeanConfiguration(currentBeanConfig);
        }
        dynamicElementReader.setBeanDecorator(decorator);
        return dynamicElementReader;
    }

    /**
	 * Sets the binding (the variables available in the scope of the GroovyBeanDefinitionReader)
	 * @param b The Binding instance
	 */
	public void setBinding(Binding b) {
		this.binding = b.getVariables();
	}



}
