/*

 * Copyright 2010, The Android Open Source Project

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *  * Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *  * Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "GeolocationPositionCache.h"

#if ENABLE(GEOLOCATION)

#include "Geoposition.h"

#include "SQLValue.h"

#include "SQLiteDatabase.h"

#include "SQLiteFileSystem.h"

#include "SQLiteStatement.h"

#include "SQLiteTransaction.h"

namespace WebCore {

static const char* databaseName = "CachedGeoposition.db";

int GeolocationPositionCache::s_instances = 0;

RefPtr<Geoposition>* GeolocationPositionCache::s_cachedPosition;

String* GeolocationPositionCache::s_databaseFile = 0;

GeolocationPositionCache::GeolocationPositionCache()

{

    if (!(s_instances++)) {

        s_cachedPosition = new RefPtr<Geoposition>;

        *s_cachedPosition = readFromDB();

    }

}

GeolocationPositionCache::~GeolocationPositionCache()

{

    if (!(--s_instances)) {

        if (*s_cachedPosition)

            writeToDB(s_cachedPosition->get());

        delete s_cachedPosition;

    }

}

void GeolocationPositionCache::setCachedPosition(Geoposition* cachedPosition)

{

    *s_cachedPosition = cachedPosition;

}

Geoposition* GeolocationPositionCache::cachedPosition()

{

    return s_cachedPosition->get();

}

void GeolocationPositionCache::setDatabasePath(const String& databasePath)

{

    if (!s_databaseFile)

        s_databaseFile = new String;

    *s_databaseFile = SQLiteFileSystem::appendDatabaseFileNameToPath(databasePath, databaseName);

    // If we don't have have a cached position, attempt to read one from the

    // DB at the new path.

    if (s_instances && !(*s_cachedPosition))

        *s_cachedPosition = readFromDB();

}

PassRefPtr<Geoposition> GeolocationPositionCache::readFromDB()

{

    SQLiteDatabase database;

    if (!s_databaseFile || !database.open(*s_databaseFile))

        return 0;

    // Create the table here, such that even if we've just created the

    // DB, the commands below should succeed.

    if (!database.executeCommand("CREATE TABLE IF NOT EXISTS CachedPosition ("

            "latitude REAL NOT NULL, "

            "longitude REAL NOT NULL, "

            "altitude REAL, "

            "accuracy REAL NOT NULL, "

            "altitudeAccuracy REAL, "

            "heading REAL, "

            "speed REAL, "

            "timestamp INTEGER NOT NULL)"))

        return 0;

    SQLiteStatement statement(database, "SELECT * FROM CachedPosition");

    if (statement.prepare() != SQLResultOk)

        return 0;

    if (statement.step() != SQLResultRow)

        return 0;

    bool providesAltitude = statement.getColumnValue(2).type() != SQLValue::NullValue;

    bool providesAltitudeAccuracy = statement.getColumnValue(4).type() != SQLValue::NullValue;

    bool providesHeading = statement.getColumnValue(5).type() != SQLValue::NullValue;

    bool providesSpeed = statement.getColumnValue(6).type() != SQLValue::NullValue;

    RefPtr<Coordinates> coordinates = Coordinates::create(statement.getColumnDouble(0), // latitude

                                                          statement.getColumnDouble(1), // longitude

                                                          providesAltitude, statement.getColumnDouble(2), // altitude

                                                          statement.getColumnDouble(3), // accuracy

                                                          providesAltitudeAccuracy, statement.getColumnDouble(4), // altitudeAccuracy

                                                          providesHeading, statement.getColumnDouble(5), // heading

                                                          providesSpeed, statement.getColumnDouble(6)); // speed

    return Geoposition::create(coordinates.release(), statement.getColumnInt64(7)); // timestamp

}

void GeolocationPositionCache::writeToDB(const Geoposition* position)

{

    ASSERT(position);

    SQLiteDatabase database;

    if (!s_databaseFile || !database.open(*s_databaseFile))

        return;

    SQLiteTransaction transaction(database);

    if (!database.executeCommand("DELETE FROM CachedPosition"))

        return;

    SQLiteStatement statement(database, "INSERT INTO CachedPosition ("

        "latitude, "

        "longitude, "

        "altitude, "

        "accuracy, "

        "altitudeAccuracy, "

        "heading, "

        "speed, "

        "timestamp) "

        "VALUES (?, ?, ?, ?, ?, ?, ?, ?)");

    if (statement.prepare() != SQLResultOk)

        return;

    statement.bindDouble(1, position->coords()->latitude());

    statement.bindDouble(2, position->coords()->longitude());

    if (position->coords()->canProvideAltitude())

        statement.bindDouble(3, position->coords()->altitude());

    else

        statement.bindNull(3);

    statement.bindDouble(4, position->coords()->accuracy());

    if (position->coords()->canProvideAltitudeAccuracy())

        statement.bindDouble(5, position->coords()->altitudeAccuracy());

    else

        statement.bindNull(5);

    if (position->coords()->canProvideHeading())

        statement.bindDouble(6, position->coords()->heading());

    else

        statement.bindNull(6);

    if (position->coords()->canProvideSpeed())

        statement.bindDouble(7, position->coords()->speed());

    else

        statement.bindNull(7);

    statement.bindInt64(8, position->timestamp());

    if (!statement.executeCommand())

        return;

    transaction.commit();

}

} // namespace WebCore

#endif // ENABLE(GEOLOCATION)