package org.drools.grid.services;

import java.util.List;

import org.drools.grid.ConnectorException;
import org.drools.grid.GenericConnection;
import org.drools.grid.GenericNodeConnector;
import org.drools.grid.HumanTaskNode;
import org.drools.grid.strategies.NodeSelectionStrategy;
import org.drools.grid.strategies.ReturnAlwaysTheFirstSelectionStrategy;

/**
 * @author salaboy
 *
 * This class represent a remote/distributed Task Server service that will let us
 * execute and manage Human Tasks associated with business processes.
 * As ExecutionEnvironment and DirectoryInstance this class can encapsulate one
 * or a set of HumanTaskNodes based on the underlaying implementation.
 *
 */
public class TaskServerInstance {

    private String                name;
    private GenericNodeConnector  connector;
    private NodeSelectionStrategy defaultStrategy = new ReturnAlwaysTheFirstSelectionStrategy();

    /*
     * Creates a new TaskServer Instance that will be associated to a name using the
     * GenericNodeConnector provided.
     * @param name
     * @param connector
     */
    public TaskServerInstance(String name,
                              GenericNodeConnector connector) {
        this.name = name;
        this.connector = connector;
    }

    /*
     * Get a HumanTaskNode based on the default NodeSelectionStrategy
     */
    public HumanTaskNode getHumanTaskNode() throws ConnectorException {
        return getHumanTaskNode( this.defaultStrategy );
    }

    /*
     * Get a HumanTaskNode based on the provided NodeSelectionStrategy
     * @param strategy
     */
    public HumanTaskNode getHumanTaskNode(NodeSelectionStrategy strategy) throws ConnectorException {
        GenericConnection connection = getConnector().getConnection();
        return connection.getHumanTaskNode( strategy );
    }

    /*
     * Get all the HumanTaskNodes inside the TaskServerInstance.
     * This can be expensive because it needs to get a connection to all the HumanTaskNodes.
     */
    public List<HumanTaskNode> getHumanTaskNodes() throws ConnectorException {
        GenericConnection connection = getConnector().getConnection();
        return connection.getHumanTaskNodes();
    }

    /*
     * Get the GenericNodeConnector from this TaskServerInstance
     */
    public GenericNodeConnector getConnector() {
        return this.connector;
    }

    /*
     * Get the TaskServerInstance name
     */
    public String getName() {
        return this.name;
    }

}