/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * 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 android.location;


import com.android.internal.location.ProviderProperties;

An abstract superclass for location providers.  A location provider
provides periodic reports on the geographical location of the
device.
 Each provider has a set of criteria under which it may be used; for example, some providers require GPS hardware and visibility to a number of satellites; others require the use of the cellular radio, or access to a specific carrier's network, or to the internet. They may also have different battery consumption characteristics or monetary costs to the user. The Criteria class allows providers to be selected based on user-specified criteria. /**
 * An abstract superclass for location providers.  A location provider
 * provides periodic reports on the geographical location of the
 * device.
 *
 * <p> Each provider has a set of criteria under which it may be used;
 * for example, some providers require GPS hardware and visibility to
 * a number of satellites; others require the use of the cellular
 * radio, or access to a specific carrier's network, or to the
 * internet.  They may also have different battery consumption
 * characteristics or monetary costs to the user.  The {@link
 * Criteria} class allows providers to be selected based on
 * user-specified criteria.
 */
public class LocationProvider {
    public static final int OUT_OF_SERVICE = 0;
    public static final int TEMPORARILY_UNAVAILABLE = 1;
    public static final int AVAILABLE = 2;

    
A regular expression matching characters that may not appear
in the name of a LocationProvider
@hide
/**
     * A regular expression matching characters that may not appear
     * in the name of a LocationProvider
     * @hide
     */
    public static final String BAD_CHARS_REGEX = "[^a-zA-Z0-9]";

    private final String mName;
    private final ProviderProperties mProperties;

    
Constructs a LocationProvider with the given name.   Provider names must
consist only of the characters [a-zA-Z0-9].
Throws:
IllegalArgumentException – if name contains an illegal character
@hide
/**
     * Constructs a LocationProvider with the given name.   Provider names must
     * consist only of the characters [a-zA-Z0-9].
     *
     * @throws IllegalArgumentException if name contains an illegal character
     *
     * @hide
     */
    public LocationProvider(String name, ProviderProperties properties) {
        if (name.matches(BAD_CHARS_REGEX)) {
            throw new IllegalArgumentException("provider name contains illegal character: " + name);
        }
        mName = name;
        mProperties = properties;
    }

    
Returns the name of this provider.
/**
     * Returns the name of this provider.
     */
    public String getName() {
        return mName;
    }

    
Returns true if this provider meets the given criteria,
false otherwise.
/**
     * Returns true if this provider meets the given criteria,
     * false otherwise.
     */
    public boolean meetsCriteria(Criteria criteria) {
        return propertiesMeetCriteria(mName, mProperties, criteria);
    }

    
@hide
/**
     * @hide
     */
    public static boolean propertiesMeetCriteria(String name, ProviderProperties properties,
            Criteria criteria) {
        if (LocationManager.PASSIVE_PROVIDER.equals(name)) {
            // passive provider never matches
            return false;
        }
        if (properties == null) {
            // unfortunately this can happen for provider in remote services
            // that have not finished binding yet
            return false;
        }

        if (criteria.getAccuracy() != Criteria.NO_REQUIREMENT &&
                criteria.getAccuracy() < properties.mAccuracy) {
            return false;
        }
        if (criteria.getPowerRequirement() != Criteria.NO_REQUIREMENT &&
                criteria.getPowerRequirement() < properties.mPowerRequirement) {
            return false;
        }
        if (criteria.isAltitudeRequired() && !properties.mSupportsAltitude) {
            return false;
        }
        if (criteria.isSpeedRequired() && !properties.mSupportsSpeed) {
            return false;
        }
        if (criteria.isBearingRequired() && !properties.mSupportsBearing) {
            return false;
        }
        if (!criteria.isCostAllowed() && properties.mHasMonetaryCost) {
            return false;
        }
        return true;
    }

    
Returns true if the provider requires access to a
data network (e.g., the Internet), false otherwise.
/**
     * Returns true if the provider requires access to a
     * data network (e.g., the Internet), false otherwise.
     */
    public boolean requiresNetwork() {
        return mProperties.mRequiresNetwork;
    }

    
Returns true if the provider requires access to a
satellite-based positioning system (e.g., GPS), false
otherwise.
/**
     * Returns true if the provider requires access to a
     * satellite-based positioning system (e.g., GPS), false
     * otherwise.
     */
    public boolean requiresSatellite() {
        return mProperties.mRequiresSatellite;
    }

    
Returns true if the provider requires access to an appropriate
cellular network (e.g., to make use of cell tower IDs), false
otherwise.
/**
     * Returns true if the provider requires access to an appropriate
     * cellular network (e.g., to make use of cell tower IDs), false
     * otherwise.
     */
    public boolean requiresCell() {
        return mProperties.mRequiresCell;
    }

    
Returns true if the use of this provider may result in a
monetary charge to the user, false if use is free.  It is up to
each provider to give accurate information.
/**
     * Returns true if the use of this provider may result in a
     * monetary charge to the user, false if use is free.  It is up to
     * each provider to give accurate information.
     */
    public boolean hasMonetaryCost() {
        return mProperties.mHasMonetaryCost;
    }

    
Returns true if the provider is able to provide altitude
information, false otherwise.  A provider that reports altitude
under most circumstances but may occassionally not report it
should return true.
/**
     * Returns true if the provider is able to provide altitude
     * information, false otherwise.  A provider that reports altitude
     * under most circumstances but may occassionally not report it
     * should return true.
     */
    public boolean supportsAltitude() {
        return mProperties.mSupportsAltitude;
    }

    
Returns true if the provider is able to provide speed
information, false otherwise.  A provider that reports speed
under most circumstances but may occassionally not report it
should return true.
/**
     * Returns true if the provider is able to provide speed
     * information, false otherwise.  A provider that reports speed
     * under most circumstances but may occassionally not report it
     * should return true.
     */
    public boolean supportsSpeed() {
        return mProperties.mSupportsSpeed;
    }

    
Returns true if the provider is able to provide bearing
information, false otherwise.  A provider that reports bearing
under most circumstances but may occassionally not report it
should return true.
/**
     * Returns true if the provider is able to provide bearing
     * information, false otherwise.  A provider that reports bearing
     * under most circumstances but may occassionally not report it
     * should return true.
     */
    public boolean supportsBearing() {
        return mProperties.mSupportsBearing;
    }

    
Returns the power requirement for this provider.
Returns:
the power requirement for this provider, as one of the
constants Criteria.POWER_REQUIREMENT_*./**
     * Returns the power requirement for this provider.
     *
     * @return the power requirement for this provider, as one of the
     * constants Criteria.POWER_REQUIREMENT_*.
     */
    public int getPowerRequirement() {
        return mProperties.mPowerRequirement;
    }

    
Returns a constant describing horizontal accuracy of this provider. If the provider returns finer grain or exact location, Criteria.ACCURACY_FINE is returned, otherwise if the location is only approximate then Criteria.ACCURACY_COARSE is returned. /**
     * Returns a constant describing horizontal accuracy of this provider.
     * If the provider returns finer grain or exact location,
     * {@link Criteria#ACCURACY_FINE} is returned, otherwise if the
     * location is only approximate then {@link Criteria#ACCURACY_COARSE}
     * is returned.
     */
    public int getAccuracy() {
        return mProperties.mAccuracy;
    }
}