// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you 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.

#pragma once

#include <stdint.h>

#include <boost/random/mersenne_twister.hpp>

#include <boost/uuid/random_generator.hpp>

#include <boost/uuid/uuid.hpp>

#include <boost/uuid/uuid_io.hpp>

#include <cstring>

#include <ostream>

#include <string>

#include <string_view>

#include "util/uuid_generator.h"

namespace doris {

class TUniqueId;

class PUniqueId;

// convert int to a hex format string, buf must enough to hold converted hex string

template <typename T>

void to_hex(T val, char* buf) {

    static const char* digits = "0123456789abcdef";

    for (size_t i = 0; i < 2 * sizeof(T); ++i) {

        buf[2 * sizeof(T) - 1 - i] = digits[val & 0x0F];

        val >>= 4;

    }

}

template <typename T>

void from_hex(T* ret, std::string_view buf) {

    T val = 0;

    for (char i : buf) {

        int buf_val = 0;

        if (i >= '0' && i <= '9') {

            buf_val = i - '0';

        } else {

            buf_val = i - 'a' + 10;

        }

        val <<= 4;

        val = val | buf_val;

    }

    *ret = val;

}

struct UniqueId {

    int64_t hi = 0;

    int64_t lo = 0;

    UniqueId() = default;

    UniqueId(int64_t hi_, int64_t lo_) : hi(hi_), lo(lo_) {}

    UniqueId(const UniqueId& uid) : hi(uid.hi), lo(uid.lo) {}

    UniqueId(const TUniqueId& tuid);

    UniqueId(const PUniqueId& puid);

    UniqueId(const std::string& hi_str, const std::string& lo_str) {

        from_hex(&hi, hi_str);

        from_hex(&lo, lo_str);

    }

    bool initialized() const { return hi != 0 || lo != 0; }

    // currently, the implementation is uuid, but it may change in the future

    static UniqueId gen_uid() {

        UniqueId uid(0, 0);

        auto uuid = UUIDGenerator::instance()->next_uuid();

        memcpy(&uid.hi, uuid.data, sizeof(int64_t));

        memcpy(&uid.lo, uuid.data + sizeof(int64_t), sizeof(int64_t));

        return uid;

    }

    ~UniqueId() noexcept {}

    std::string to_string() const {

        char buf[33];

        to_hex(hi, buf);

        buf[16] = '-';

        to_hex(lo, buf + 17);

        return {buf, 33};

    }

    UniqueId& operator=(const UniqueId uid) {

        hi = uid.hi;

        lo = uid.lo;

        return *this;

    }

    UniqueId& operator=(const PUniqueId puid);

    UniqueId& operator=(const TUniqueId tuid);

    //compare PUniqueId and UniqueId

    bool operator==(const PUniqueId& rhs) const;

    bool operator!=(const PUniqueId& rhs) const;

    // std::map std::set needs this operator

    bool operator<(const UniqueId& right) const {

        if (hi != right.hi) {

            return hi < right.hi;

        } else {

            return lo < right.lo;

        }

    }

    // std::unordered_map need this api

    size_t hash(size_t seed = 0) const;

    // std::unordered_map need this api

    bool operator==(const UniqueId& rhs) const { return hi == rhs.hi && lo == rhs.lo; }

    bool operator!=(const UniqueId& rhs) const { return hi != rhs.hi || lo != rhs.lo; }

    TUniqueId to_thrift() const;

    PUniqueId to_proto() const;

};

// This function must be called 'hash_value' to be picked up by boost.

std::size_t hash_value(const doris::TUniqueId& id);

/// generates a 16 byte UUID

inline std::string generate_uuid_string() {

    return boost::uuids::to_string(boost::uuids::basic_random_generator<boost::mt19937>()());

}

/// generates a 16 byte UUID

TUniqueId generate_uuid();

std::ostream& operator<<(std::ostream& os, const UniqueId& uid);

std::string print_id(const UniqueId& id);

std::string print_id(const TUniqueId& id);

std::string print_id(const PUniqueId& id);

} // namespace doris

template <>

struct std::hash<doris::UniqueId> {

    size_t operator()(const doris::UniqueId& uid) const { return uid.hash(); }

};