// 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 <cstdint>

#include <iosfwd>

#include <string>

namespace doris {

class TUniqueId;

class PUniqueId;

// A value snapshot. It never retains a query, a resource context, or an RPC request.

struct QueryLogIdentity {

    uint64_t query_hi = 0;

    uint64_t query_lo = 0;

    uint64_t instance_hi = 0;

    uint64_t instance_lo = 0;

    QueryLogIdentity() = default;

    explicit QueryLogIdentity(const TUniqueId& query_id);

    explicit QueryLogIdentity(const PUniqueId& query_id);

    QueryLogIdentity(const TUniqueId& query_id, const TUniqueId& instance_id);

    QueryLogIdentity(const PUniqueId& query_id, const PUniqueId& instance_id);

};

// Called during logging initialization, before worker threads start. The bthread key

// has process lifetime. Reading the identity never creates thread-local resources.

void init_query_log_context();

QueryLogIdentity current_query_log_identity();

void append_query_log_identity(std::ostream& stream);

// A message suffix for an ID not already present in the runtime log prefix. Keeps

// query attribution when prefix logging is disabled or the caller has no context.

// Do not use for audit/protocol fields or IDs describing relationships between queries.

std::string query_id_log_suffix(const TUniqueId& query_id);

// The installed pointer refers to this stack object and is restored before it dies.

// bthreads use their own key, so yielding or migrating cannot expose a pthread's ID.

class ScopedQueryLogContext {

public:

    ScopedQueryLogContext() = default;

    explicit ScopedQueryLogContext(QueryLogIdentity identity) { reset(identity); }

    ~ScopedQueryLogContext();

    ScopedQueryLogContext(const ScopedQueryLogContext&) = delete;

    ScopedQueryLogContext& operator=(const ScopedQueryLogContext&) = delete;

    ScopedQueryLogContext(ScopedQueryLogContext&&) = delete;

    ScopedQueryLogContext& operator=(ScopedQueryLogContext&&) = delete;

    // Replacing the current identity does not replace the saved outer scope.

    void reset(QueryLogIdentity identity);

private:

    QueryLogIdentity _identity;

    QueryLogIdentity* _previous = nullptr;

    bool _installed = false;

};

} // namespace doris