package com.onaro.sanscreen.client.view.tabular;

import java.util.EventObject;

/**
 * Describes a change to the grouping configuration.
 */
public class GroupingConfigEvent extends EventObject {

    private static final long serialVersionUID = 1L;

    /**
     * The active schema <b>before</b> the change occured. Relevent only if the change
     * describes a change to the active schema.
     */
    private GroupingConfig.Schema oldSchema;

    /**
     * The active schema <b>after</b> the change occured. Relevent only if the change
     * describes a change to the active schema.
     */
    private GroupingConfig.Schema newSchema;

    /**
     * True if this change describes a change in the active schema.
     */
    private boolean currentSchemaChanged;

    /**
     * Crates an event reporting on a change to the active schema.
     * @param source the {@link GroupingConfig} that changed
     * @param oldSchema the active schema <b>before</b> the change
     * @param newSchema the active schema <b>after</b> the change
     */
    public GroupingConfigEvent(Object source, GroupingConfig.Schema oldSchema,
                               GroupingConfig.Schema newSchema) {
        super(source);
        this.oldSchema = oldSchema;
        this.newSchema = newSchema;
        currentSchemaChanged = true;
    }

    /**
     * Gets the active schema <b>before</b> the change occured. Relevent only if the change
     * describes a change to the active schema.
     * @return the active schema <b>before</b> the change
     */
    public GroupingConfig.Schema getOldSchema() {
        return oldSchema;
    }

    /**
     * Gets the active schema <b>after</b> the change occured. Relevent only if the change
     * describes a change to the active schema.
     * @return the active schema <b>after</b> the change
     */
    public GroupingConfig.Schema getNewSchema() {
        return newSchema;
    }

    /**
     * Tells if this change tells that the active schema changed.
     * @return true if the active schema changed
     */
    public boolean isCurrentSchemaChanged() {
        return currentSchemaChanged;
    }
}