package net.sourceforge.fenixedu.domain.accessControl;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;

import net.sourceforge.fenixedu.domain.accessControl.groups.language.Argument;
import net.sourceforge.fenixedu.injectionCode.IGroup;

public abstract class NodeGroup extends Group {

    private static final long serialVersionUID = 1L;

    private final List<IGroup> children;

    protected NodeGroup() {
	super();

	this.children = new ArrayList<IGroup>();
    }

    public NodeGroup(IGroup... groups) {
	this();

	for (IGroup group : groups) {
	    this.children.add(group);
	}
    }

    public NodeGroup(Collection<IGroup> groups) {
	this();

	this.children.addAll(groups);
    }

    public List<IGroup> getChildren() {
	return Collections.unmodifiableList(this.children);
    }

    @Override
    public boolean equals(Object other) {
	if (other == null) {
	    return false;
	}

	if (!this.getClass().equals(other.getClass())) {
	    return false;
	}

	NodeGroup otherNodeGroup = (NodeGroup) other;
	return this.children.equals(otherNodeGroup.children);
    }

    @Override
    public int hashCode() {
	return this.children.hashCode();
    }

    @Override
    public String getExpression() {
	StringBuilder builder = new StringBuilder();

	Iterator<IGroup> iterator = getChildren().iterator();
	while (iterator.hasNext()) {
	    builder.append(getChildrenExpression(iterator.next()));

	    if (iterator.hasNext()) {
		builder.append(" " + getExpressionOperator() + " ");
	    }
	}

	return builder.toString();
    }

    private String getChildrenExpression(IGroup group) {
	if (group instanceof NodeGroup) {
	    return "(" + group.getExpression() + ")";
	} else {
	    return group.getExpression();
	}
    }

    protected abstract String getExpressionOperator();

    @Override
    protected Argument[] getExpressionArguments() {
	return new Argument[0];
    }

}