// 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.

#include "io/fs/broker_file_reader.h"

#include <gen_cpp/TPaloBrokerService.h>

#include <string.h>

#include <thrift/Thrift.h>

#include <thrift/transport/TTransportException.h>

// IWYU pragma: no_include <bits/chrono.h>

#include <chrono> // IWYU pragma: keep

#include <ostream>

#include <string>

#include <thread>

#include <utility>

#include "common/compiler_util.h" // IWYU pragma: keep

#include "common/logging.h"

#include "common/metrics/doris_metrics.h"

#include "common/status.h"

#include "io/fs/broker_file_system.h"

namespace doris::io {

struct IOContext;

BrokerFileReader::BrokerFileReader(const TNetworkAddress& broker_addr, Path path, size_t file_size,

                                   TBrokerFD fd,

                                   std::shared_ptr<BrokerServiceConnection> connection,

                                   int64_t mtime)

        : _path(std::move(path)),

          _file_size(file_size),

          _broker_addr(broker_addr),

          _fd(fd),

          _connection(std::move(connection)),

          _mtime(mtime) {

    DorisMetrics::instance()->broker_file_open_reading->increment(1);

    DorisMetrics::instance()->broker_file_reader_total->increment(1);

}

BrokerFileReader::~BrokerFileReader() {

    static_cast<void>(BrokerFileReader::close());

}

Status BrokerFileReader::close() {

    bool expected = false;

    if (_closed.compare_exchange_strong(expected, true, std::memory_order_acq_rel)) {

        if (!_connection->is_alive()) {

            return Status::InternalError("connect to broker failed");

        }

        TBrokerCloseReaderRequest request;

        request.__set_version(TBrokerVersion::VERSION_ONE);

        request.__set_fd(_fd);

        TBrokerOperationStatus response;

        try {

            try {

                (*_connection)->closeReader(response, request);

            } catch (apache::thrift::transport::TTransportException&) {

                std::this_thread::sleep_for(std::chrono::seconds(1));

                RETURN_IF_ERROR((*_connection).reopen());

                (*_connection)->closeReader(response, request);

            }

        } catch (apache::thrift::TException& e) {

            std::stringstream ss;

            ss << "close broker file failed, broker:" << _broker_addr << " failed:" << e.what();

            return Status::RpcError(ss.str());

        }

        if (response.statusCode != TBrokerOperationStatusCode::OK) {

            std::stringstream ss;

            ss << "close broker file failed, broker:" << _broker_addr

               << " failed:" << response.message;

            return Status::InternalError(ss.str());

        }

        DorisMetrics::instance()->broker_file_open_reading->increment(-1);

    }

    return Status::OK();

}

Status BrokerFileReader::read_at_impl(size_t offset, Slice result, size_t* bytes_read,

                                      const IOContext* /*io_ctx*/) {

    if (closed()) [[unlikely]] {

        return Status::InternalError("read closed file: ", _path.native());

    }

    size_t bytes_req = result.size;

    char* to = result.data;

    *bytes_read = 0;

    if (UNLIKELY(bytes_req == 0)) {

        return Status::OK();

    }

    if (!_connection->is_alive()) {

        return Status::InternalError("connect to broker failed");

    }

    TBrokerPReadRequest request;

    request.__set_version(TBrokerVersion::VERSION_ONE);

    request.__set_fd(_fd);

    request.__set_offset(offset);

    request.__set_length(bytes_req);

    TBrokerReadResponse response;

    try {

        VLOG_RPC << "send pread request to broker:" << _broker_addr << " position:" << offset

                 << ", read bytes length:" << bytes_req;

        try {

            (*_connection)->pread(response, request);

        } catch (apache::thrift::transport::TTransportException& e) {

            std::this_thread::sleep_for(std::chrono::seconds(1));

            RETURN_IF_ERROR((*_connection).reopen());

            LOG(INFO) << "retry reading from broker: " << _broker_addr << ". reason: " << e.what();

            (*_connection)->pread(response, request);

        }

    } catch (apache::thrift::TException& e) {

        std::stringstream ss;

        ss << "read broker file failed, broker:" << _broker_addr << " failed:" << e.what();

        return Status::RpcError(ss.str());

    }

    if (response.opStatus.statusCode == TBrokerOperationStatusCode::END_OF_FILE) {

        // read the end of broker's file

        return Status::OK();

    }

    if (response.opStatus.statusCode != TBrokerOperationStatusCode::OK) {

        std::stringstream ss;

        ss << "Open broker reader failed, broker:" << _broker_addr

           << " failed:" << response.opStatus.message;

        return Status::InternalError(ss.str());

    }

    *bytes_read = response.data.size();

    memcpy(to, response.data.data(), *bytes_read);

    return Status::OK();

}

} // namespace doris::io