/*
 ***************************************************************************************
 *  Copyright (C) 2006 EsperTech, Inc. All rights reserved.                            *
 *  http://www.espertech.com/esper                                                     *
 *  http://www.espertech.com                                                           *
 *  ---------------------------------------------------------------------------------- *
 *  The software in this package is published under the terms of the GPL license       *
 *  a copy of which has been included with this distribution in the license.txt file.  *
 ***************************************************************************************
 */
package com.espertech.esper.client.soda;

import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;

/**
 * A stream upon which projections (views) can be added that selects events by name and filter expression.
 */
public class FilterStream extends ProjectedStream {
    private Filter filter;
    private static final long serialVersionUID = -7234330289222721729L;

    /**
     * Ctor.
     */
    public FilterStream() {
    }

    /**
     * Creates a stream using a filter that provides the event type name and filter expression to filter for.
     *
     * @param filter defines what to look for
     * @return stream
     */
    public static FilterStream create(Filter filter) {
        return new FilterStream(filter);
    }

    /**
     * Creates a stream of events of the given name.
     *
     * @param eventTypeName is the event type name to filter for
     * @return stream
     */
    public static FilterStream create(String eventTypeName) {
        return new FilterStream(Filter.create(eventTypeName));
    }

    /**
     * Creates a stream of events of the given event type name and names that stream. Example: "select * from MyeventTypeName as StreamName".
     *
     * @param eventTypeName is the event type name to filter for
     * @param streamName    is an optional stream name
     * @return stream
     */
    public static FilterStream create(String eventTypeName, String streamName) {
        return new FilterStream(Filter.create(eventTypeName), streamName);
    }

    /**
     * Creates a stream using a filter that provides the event type name and filter expression to filter for.
     *
     * @param filter     defines what to look for
     * @param streamName is an optional stream name
     * @return stream
     */
    public static FilterStream create(Filter filter, String streamName) {
        return new FilterStream(filter, streamName);
    }

    /**
     * Creates a stream of events of the given event type name and names that stream. Example: "select * from MyeventTypeName as StreamName".
     *
     * @param eventTypeName is the event type name to filter for
     * @param filter        is the filter expression removing events from the stream
     * @return stream
     */
    public static FilterStream create(String eventTypeName, Expression filter) {
        return new FilterStream(Filter.create(eventTypeName, filter));
    }

    /**
     * Creates a stream of events of the given event type name and names that stream. Example: "select * from MyeventTypeName as StreamName".
     *
     * @param eventTypeName is the event type name to filter for
     * @param filter        is the filter expression removing events from the stream
     * @param streamName    is an optional stream name
     * @return stream
     */
    public static FilterStream create(String eventTypeName, String streamName, Expression filter) {
        return new FilterStream(Filter.create(eventTypeName, filter), streamName);
    }

    /**
     * Ctor.
     *
     * @param filter specifies what events to look for
     */
    public FilterStream(Filter filter) {
        super(new ArrayList<View>(), null);
        this.filter = filter;
    }

    /**
     * Ctor.
     *
     * @param filter specifies what events to look for
     * @param name   is the as-name for the stream
     */
    public FilterStream(Filter filter, String name) {
        super(new ArrayList<View>(), name);
        this.filter = filter;
    }

    /**
     * Ctor.
     *
     * @param filter specifies what events to look for
     * @param name   is the as-name for the stream
     * @param views  is a list of projections onto the stream
     */
    public FilterStream(Filter filter, String name, List<View> views) {
        super(views, name);
        this.filter = filter;
    }

    /**
     * Returns the filter.
     *
     * @return filter
     */
    public Filter getFilter() {
        return filter;
    }

    /**
     * Sets the filter to use.
     *
     * @param filter to set
     */
    public void setFilter(Filter filter) {
        this.filter = filter;
    }

    public void toEPLProjectedStream(StringWriter writer, EPStatementFormatter formatter) {
        filter.toEPL(writer, formatter);
    }

    public void toEPLProjectedStreamType(StringWriter writer) {
        writer.write(filter.getEventTypeName());
    }
}