/*
 * Copyright 2016 Anton Tananaev (anton@traccar.org)
 *
 * Licensed 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.traccar.events;

import java.util.Collection;
import java.util.Collections;

import org.traccar.BaseEventHandler;
import org.traccar.Context;
import org.traccar.model.Device;
import org.traccar.model.Event;
import org.traccar.model.Position;

public class MotionEventHandler extends BaseEventHandler {

    private double speedThreshold;

    public MotionEventHandler() {
        speedThreshold = Context.getConfig().getDouble("event.motion.speedThreshold", 0.01);
    }

    @Override
    protected Collection<Event> analyzePosition(Position position) {

        Device device = Context.getIdentityManager().getDeviceById(position.getDeviceId());
        if (device == null) {
            return null;
        }
        if (!Context.getIdentityManager().isLatestPosition(position) || !position.getValid()) {
            return null;
        }

        double speed = position.getSpeed();
        double oldSpeed = 0;
        Position lastPosition = Context.getIdentityManager().getLastPosition(position.getDeviceId());
        if (lastPosition != null) {
            oldSpeed = lastPosition.getSpeed();
        }
        if (speed > speedThreshold && oldSpeed <= speedThreshold) {
            return Collections.singleton(
                    new Event(Event.TYPE_DEVICE_MOVING, position.getDeviceId(), position.getId()));
        } else if (speed <= speedThreshold && oldSpeed > speedThreshold) {
            return Collections.singleton(
                    new Event(Event.TYPE_DEVICE_STOPPED, position.getDeviceId(), position.getId()));
        }
        return null;
    }

}