package smartbox;

import java.util.*;
import java.io.*;
import java.lang.reflect.*;
import java.net.*;
import mvc.*;


public class Container extends Model {

	private Map<Class<?>, Component> providedInterfaces = new HashMap<Class<?>, Component>();
	private Map<Class<?>, Component> requiredInterfaces = new HashMap<Class<?>, Component>();
        private Map<String, Component> components = new HashMap<String, Component>();

	public Collection<Component> getComponents() {
		return components.values();
	}

	public void addComponent(String name) throws Exception {
		String qualName = "smartbox.components." +  name;
		// Object obj = a new instance of qualName
		addComponent((Component)obj);
	}


	private void addComponent(Component component) throws Exception {
		component.setContainer(this);
		// add new guy to the componebnts table:
		components.put(component.name, component);
		// update provided interfaces table:
		for(Class<?> intf: component.getProvidedInterfaces()) {
			providedInterfaces.put(intf,  component);
		}
		// update required interfaces table:
		//???
		//find providers for the new component and hook him up:
		findProviders();
		// mvc stuff:
		changed();
	}

	public void remComponent(String name) throws Exception {
		Component component = components.get(name);
		components.remove(name);
		// unhook removed guy from any clients:
		for(Class<?> intf: component.getProvidedInterfaces()) {
			for(Component client: components.values()) {
				if (client.getRequiredInterfaces().contains(intf)) {
					client.setProvider(intf,  null);
					requiredInterfaces.put(intf, client);
				}
			}
		}
		changed();
	}

	// each time we add a new component we try to connect as many clients and providers as we can:
	private void findProviders() throws Exception {
		Set<Class<?>> reqInterfaces = requiredInterfaces.keySet();
		for(Class<?> intf: reqInterfaces) {
			Component client = requiredInterfaces.get(intf);
			Component provider = providedInterfaces.get(intf);
			if (client != null && provider != null) {
				client.setProvider(intf,  provider);
				//requiredInterfaces.remove(intf); this line makes iterator obsolete
				requiredInterfaces.put(intf, null);
			}
		}
	}

	public void launch(String name) throws Exception {
	    try {
               // look up component and call main if it's an App
	    } catch(Exception e) {
	       mvc.Utilities.error(e);
               e.printStackTrace();
	    }
	}

        // needed by File/Open to restore component.fields
	public void initContainer(){
		for(Component c: components.values()) c.initComponent();
		changed(); // needed?
    }

}