// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.ui.def.nonpublic.support;

import org.litesoft.ui.def.*;

public interface UiChildrenHelper
{
    /**
     * @return null if no children
     */
    public UiDef getFirstChild();

    /**
     * @return !null
     */
    public UiDef[] getChildren();

    /**
     * @param pChild if null then ignored
     */
    public void addChild( UiDef pChild );

    /**
     * @param pChild if null then ignored
     * @param pAt    0 for new First, anything < 0 or >= current child count simply adds to the end
     */
    public void insertChildBefore( UiDef pChild, int pAt );

    /**
     * @param pChild if null then ignored
     *
     * @return true if removed
     */
    public boolean removeChild( UiDef pChild );

    /**
     * @param pAt 0 for first child, anything < 0 or >= current child count removes nothing
     *
     * @return null or child removed
     */
    public UiDef removeChildAt( int pAt );

    /**
     * @param pChild null is unacceptable
     *
     * @return true if acceptable
     */
    public boolean acceptableChild( UiDef pChild );

    /**
     * @return ???.class of the acceptableChild
     */
    public Object getAcceptableChildClass();

    /**
     * @param pActionOrInput null returns null
     *
     * @return null if Unsupported
     */
    public UiDef convertToActionOrInput( String pActionOrInput );

    /**
     * @return The Minimum Children required (> 0)
     */
    public int getMinChildren();

    /**
     * @return The Maximum Children allowed (unlimited = 0, otherwise >= Min Children)
     */
    public int getMaxChildren();
}