package pt.ist.renderers.extensions.factories;

import java.util.Arrays;
import java.util.Collection;
import java.util.List;

import pt.ist.fenixframework.DomainObject;
import pt.ist.renderers.extensions.util.ObjectChange;
import pt.ist.renderers.extensions.util.ObjectKey;
import pt.ist.renderers.model.InstanceCreator;
import pt.ist.renderers.model.MetaObjectKey;

public class CreationDomainMetaObject extends DomainMetaObject {
    private Class type;

    public CreationDomainMetaObject(Class type) {
	super();

	setType(type);
	setOid(0);
    }

    public MetaObjectKey getKey() {
	return new CreationMetaObjectKey(getType());
    }

    @Override
    public Class getType() {
	return type;
    }

    public void setType(Class type) {
	this.type = type;
    }

    @Override
    protected Object callService(List<ObjectChange> changes) {
	Object result = super.callService(changes);
	setObject(((Collection) result).iterator().next());

	return result;
    }

    @Override
    protected DomainObject getPersistentObject() {
	return null;
    }

    public static class CreationServicePredicateWithResult extends ServicePredicateWithResult {

	DomainMetaObject domainMetaObject;

	public CreationServicePredicateWithResult(List<ObjectChange> changes, final DomainMetaObject domainMetaObject) {
	    super(changes);
	    this.domainMetaObject = domainMetaObject;
	}

	@Override
	public void execute() {
	    beforeRun(changes);

	    InstanceCreator instanceCreator = domainMetaObject.getInstanceCreator();
	    if (instanceCreator != null) {
		long oid = domainMetaObject.getOid();
		ObjectKey key = new ObjectKey(oid, domainMetaObject.getType());

		try {
		    changes.add(0, new ObjectChange(key, instanceCreator.getConstructor(), instanceCreator.getArgumentValues()));
		} catch (Exception e) {
		    throw new RuntimeException("could not find constructor for '" + domainMetaObject.getType().getName()
			    + "' with arguments "
			    + Arrays.asList(instanceCreator.getArgumentTypes()), e);
		}
	    }

	    super.execute();
	}

	@Override
	protected DomainObject getNewObject(ObjectChange change) {
	    try {
		Class objectClass = change.key.getType();

		if (change.constructor != null) {
		    return (DomainObject) change.constructor.newInstance(change.values);
		} else {
		    return (DomainObject) objectClass.newInstance();
		}
	    } catch (Exception e) {
		if (e.getCause() instanceof Error) {
		    throw (Error) e.getCause();
		} else if (e.getCause() instanceof RuntimeException) {
		    throw (RuntimeException) e.getCause();
		}

		throw new Error(e);
	    }
	}

    }

    @Override
    protected ServicePredicateWithResult getServiceToCall(List<ObjectChange> changes) {
	return new CreationServicePredicateWithResult(changes, this);
    }
}