/*    Copyright 2012 10gen Inc.
 *
 *    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.
 */

/**
 * Utility functions for parsing numbers from strings.
 */

#pragma once

#include "mongo/base/status.h"
#include "mongo/base/string_data.h"

namespace mongo {

    /**
     * Parses a number out of a StringData.
     *
     * Parses "stringValue", interpreting it as a number of the given "base".  On success, stores
     * the parsed value into "*result" and returns Status::OK().
     *
     * Valid values for "base" are 2-36, with 0 meaning "choose the base by inspecting the prefix
     * on the number", as in strtol.  Returns Status::BadValue if an illegal value is supplied for
     * "base".
     *
     * The entirety of the string must consist of digits in the given base, except optionally the
     * first character may be "+" or "-", and hexadecimal numbers may begin "0x".  Same as strtol,
     * without the property of stripping whitespace at the beginning, and fails to parse if there
     * are non-digit characters at the end of the string.
     *
     * See parse_number.cpp for the available instantiations, and add any new instantiations there.
     */
    template <typename NumberType>
    Status parseNumberFromStringWithBase(const StringData& stringValue, int base, NumberType* result);

    template <typename NumberType>
    static Status parseNumberFromString(const StringData& stringValue, NumberType* result) {
        return parseNumberFromStringWithBase(stringValue, 0, result);
    }

}  // namespace mongo