// stringutils.h


/**
 *    Copyright (C) 2018-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    This program 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
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the Server Side Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#pragma once

#include <ctype.h>

#include <boost/optional.hpp>
#include <memory>
#include <string>
#include <vector>

#include "mongo/base/string_data.h"

namespace mongo {

// see also mongoutils/str.h - perhaps move these there?
// see also text.h

void splitStringDelim(const std::string& str, std::vector<std::string>* res, char delim);

void joinStringDelim(const std::vector<std::string>& strs, std::string* res, char delim);

inline std::string tolowerString(StringData input) {
    std::string::size_type sz = input.size();

    std::unique_ptr<char[]> line(new char[sz + 1]);
    char* copy = line.get();

    for (std::string::size_type i = 0; i < sz; i++) {
        char c = input[i];
        copy[i] = (char)tolower((int)c);
    }
    copy[sz] = 0;
    return copy;
}

inline std::string toAsciiLowerCase(StringData input) {
    size_t sz = input.size();
    std::unique_ptr<char[]> line(new char[sz + 1]);
    char* res = line.get();
    for (size_t i = 0; i < sz; i++) {
        char c = input[i];
        if (c >= 'A' && c <= 'Z') {
            res[i] = c + 32;
        } else {
            res[i] = c;
        }
    }
    res[sz] = 0;
    return res;
}

/** Functor for combining lexical and numeric comparisons. */
class LexNumCmp {
public:
    /** @param lexOnly - compare all characters lexically, including digits. */
    LexNumCmp(bool lexOnly);
    /**
     * Non numeric characters are compared lexicographically; numeric substrings
     * are compared numerically; dots separate ordered comparable subunits.
     * For convenience, character 255 is greater than anything else.
     * @param lexOnly - compare all characters lexically, including digits.
     */
    static int cmp(StringData s1, StringData s2, bool lexOnly);
    int cmp(StringData s1, StringData s2) const;
    bool operator()(StringData s1, StringData s2) const;

private:
    bool _lexOnly;
};

// TODO: Sane-ify core std::string functionality
// For now, this needs to be near the LexNumCmp or else
int versionCmp(const StringData rhs, const StringData lhs);

/**
 * A method to escape whitespace and control characters in strings. For example, the string "\t"
 * goes to "\\t". If `escape_slash` is true, then "/" goes to "\\/".
 */
std::string escape(StringData s, bool escape_slash = false);

/**
 * Converts 'integer' from a base-10 string to a size_t value or returns boost::none if 'integer'
 * is not a valid base-10 string. A valid string is not allowed to have anything but decimal
 * numerals, not even a +/- prefix or leading/trailing whitespace.
 */
boost::optional<size_t> parseUnsignedBase10Integer(StringData integer);

}  // namespace mongo