/*
 * Copyright (c) 2017, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 * WSO2 Inc. licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.wso2.carbon.event.simulator.core.internal.generator;

import org.json.JSONObject;
import org.wso2.carbon.event.simulator.core.exception.InsufficientAttributesException;
import org.wso2.carbon.event.simulator.core.exception.InvalidConfigException;
import org.wso2.carbon.stream.processor.common.exception.ResourceNotFoundException;
import org.wso2.siddhi.core.event.Event;

/**
 * Interface which defines the common methods used by all event generators
 */
public interface EventGenerator {

    void init(JSONObject sourceConfig, long startTimestamp, long endTimestamp) throws InvalidConfigException,
            ResourceNotFoundException;

    void start();

    void stop();

    Event poll();

    Event peek();

    void getNextEvent();

    String getStreamName();

    String getSiddhiAppName();

    void validateSourceConfiguration(JSONObject sourceConfig) throws InvalidConfigException,
            InsufficientAttributesException, ResourceNotFoundException;

    void setStartTimestamp(long startTimestamp);

    /**
     * Generator type for an input stream can be
     * 1. Random Data Simulation
     * 2. CSV Simulation
     * 3. Database Simulation
     * 4. Single Event Simulation
     */
    enum GeneratorType {
        CSV_SIMULATION, RANDOM_DATA_SIMULATION, DATABASE_SIMULATION
    }

}
