/*
 * Copyright (C) 2014 Aaron Seigo <aseigo@kde.org>
 * Copyright (C) 2014 Christian Mollekopf <mollekopf@kolabsys.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) version 3, or any
 * later version accepted by the membership of KDE e.V. (or its
 * successor approved by the membership of KDE e.V.), which shall
 * act as a proxy defined in Section 6 of version 3 of the license.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "storage.h"

#include <iostream>

namespace Akonadi2
{

static const char *s_internalPrefix = "__internal";
static const int s_internalPrefixSize = strlen(s_internalPrefix);

void errorHandler(const Storage::Error &error)
{
    //TODO: allow this to be turned on / off globally
    //TODO: log $SOMEWHERE $SOMEHOW rather than just spit to stderr
    std::cout << "Read error in " << error.store.toStdString() << ", code " << error.code << ", message: " << error.message.toStdString() << std::endl;
}

std::function<void(const Storage::Error &error)> Storage::basicErrorHandler()
{
    return errorHandler;
}

void Storage::setDefaultErrorHandler(const std::function<void(const Storage::Error &error)> &errorHandler)
{
    mErrorHandler = errorHandler;
}

std::function<void(const Storage::Error &error)> Storage::defaultErrorHandler()
{
    if (mErrorHandler) {
        return mErrorHandler;
    }
    return basicErrorHandler();
}

int Storage::scan(const QByteArray &key, const std::function<bool(const QByteArray &value)> &resultHandler, const std::function<void(const Storage::Error &error)> &errorHandler)
{
    return scan(key, [&resultHandler](void *keyPtr, int keySize, void *valuePtr, int valueSize) {
        return resultHandler(QByteArray::fromRawData((char*)(valuePtr), valueSize));
    },
    errorHandler);
}

bool Storage::write(const QByteArray &sKey, const QByteArray &sValue, const std::function<void(const Storage::Error &error)> &errorHandler)
{
    return write(const_cast<char*>(sKey.data()), sKey.size(), const_cast<char*>(sValue.data()), sValue.size(), errorHandler);
}

void Storage::setMaxRevision(qint64 revision)
{
    write("__internal_maxRevision", QByteArray::number(revision));
}

qint64 Storage::maxRevision()
{
    qint64 r = 0;
    scan("__internal_maxRevision", [&](const QByteArray &revision) -> bool {
        r = revision.toLongLong();
        return false;
    }, [this](const Error &error){
        if (error.code != ErrorCodes::NotFound) {
            defaultErrorHandler()(error);
        }
    });
    return r;
}

bool Storage::isInternalKey(const char *key)
{
    return key && strncmp(key, s_internalPrefix, s_internalPrefixSize) == 0;
}

bool Storage::isInternalKey(void *key, int size)
{
    if (size < 1) {
        return false;
    }

    return key && strncmp(static_cast<char *>(key), s_internalPrefix, (size > s_internalPrefixSize ? s_internalPrefixSize : size)) == 0;
}

bool Storage::isInternalKey(const QByteArray &key)
{
    return key.startsWith(s_internalPrefix);
}

} // namespace Akonadi2