package org.oddjob.values;

import java.util.LinkedHashMap;
import java.util.Map;

import org.apache.commons.beanutils.expression.DefaultResolver;
import org.apache.commons.beanutils.expression.Resolver;
import org.oddjob.arooa.ArooaException;
import org.oddjob.arooa.ArooaValue;
import org.oddjob.arooa.reflect.ArooaPropertyException;
import org.oddjob.arooa.reflect.PropertyAccessor;
import org.oddjob.framework.SimpleJob;


/**
 * @oddjob.description A job which sets properties in other
 * jobs when it executes.
 * 
 * @oddjob.example
 * 
 * Setting lots of properties. 
 * 
 * {@oddjob.xml.resource org/oddjob/values/set-test.xml}
 * 
 * This is the configuration for one
 * of the tests.
 */

public class SetJob extends SimpleJob {
    
	
	private final Map<String, ArooaValue> values = 
		new LinkedHashMap<String, ArooaValue>();
	
    /**
	 * Add a name value pair. 
	 * 
     * @oddjob.property values
     * @oddjob.description The thing to set on the property that is given by
     * the key of this mapped property.
     * @oddjob.required No, but pointless if not provided.
 	 * 
	 * @param name The name of the variable.
	 * @param value The runtime configurable for the value.
	 */
	public void setValues(String name, ArooaValue value) {		
		values.put(name, value);
	}
	
	/*
	 *  (non-Javadoc)
	 * @see org.oddjob.jobs.AbstractJob#execute()
	 */
	protected int execute() throws Exception {
		
		for (Map.Entry<String, ArooaValue> entry : values.entrySet()) {
			String name = entry.getKey();
			ArooaValue value = entry.getValue();
			logger().info("Setting [" + name + "] = [" + value + "]");
			setProperty(name, value);
		}
		
		return 0;
	}


	/**
	 * Set a property on a Component in the registry. This method
	 * will resolve the valueFor before setting the property. This might
	 * not be the desired result for things like variables. The 
	 * way round this would be to create a dummy type ProxyType which
	 * the DynaClass of VariablesJob, SetJob etc would return and which
	 * valueFor methods would recognize and would return themselves as the
	 * valueFor - but that's a lot of work and propbably isn't requied
	 * much. 
	 * <p>
	 * This method should really be a lot better at resolving the types of
	 * nested beans for property conversion. This method only goes as far as
	 * resolving past component id so the correct type of component is used.
	 */
	private void setProperty(
			String property, ArooaValue value) 
	throws ArooaPropertyException {
		
		Resolver resolver = new DefaultResolver();
		
		String compName = resolver.next(property);

		String propertyExpression = resolver.remove(property);
		
		if ( propertyExpression == null) {
			throw new ArooaException("No thing specified to set property on.");
		}
				
		Object component = getArooaSession().getBeanRegistry(
				).lookup(compName);
		
		if (component == null) {
			throw new ArooaException("No component [" + 
					compName + "]");
		}
		
		PropertyAccessor propertyAccessor = 
			getArooaSession().getTools().getPropertyAccessor();
		
		propertyAccessor = propertyAccessor.accessorWithConversions(
				getArooaSession().getTools().getArooaConverter());
		
		propertyAccessor.setProperty(component, propertyExpression, value);
	}
}