// 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/local_file_reader.h"

#include <bthread/bthread.h>

// IWYU pragma: no_include <bthread/errno.h>

#include <bvar/bvar.h>

#include <errno.h> // IWYU pragma: keep

#include <fmt/format.h>

#include <glog/logging.h>

#include <unistd.h>

#include <algorithm>

#include <atomic>

#include <cstring>

#include <string>

#include <utility>

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

#include "common/metrics/doris_metrics.h"

#include "cpp/sync_point.h"

#include "io/fs/err_utils.h"

#include "runtime/thread_context.h"

#include "runtime/workload_management/io_throttle.h"

#include "storage/data_dir.h"

#include "storage/olap_common.h"

#include "storage/options.h"

#include "util/async_io.h"

#include "util/debug_points.h"

#include "util/defer_op.h"

namespace doris {

namespace io {

// 1: initing 2: inited 0: before init

std::atomic_int BeConfDataDirReader::be_config_data_dir_list_state = 0;

std::vector<doris::DataDirInfo> BeConfDataDirReader::be_config_data_dir_list;

void BeConfDataDirReader::get_data_dir_by_file_path(io::Path* file_path,

                                                    std::string* data_dir_arg) {

    int state = be_config_data_dir_list_state.load(std::memory_order_acquire);

    if (state == 0) [[unlikely]] {

        return;

    } else if (state == 1) [[unlikely]] {

        be_config_data_dir_list_state.wait(1);

    }

    for (const auto& data_dir_info : be_config_data_dir_list) {

        if (data_dir_info.path.size() >= file_path->string().size()) {

            continue;

        }

        if (file_path->string().compare(0, data_dir_info.path.size(), data_dir_info.path) == 0) {

            *data_dir_arg = data_dir_info.path;

            break;

        }

    }

}

void BeConfDataDirReader::init_be_conf_data_dir(

        const std::vector<doris::StorePath>& store_paths,

        const std::vector<doris::StorePath>& spill_store_paths,

        const std::vector<doris::CachePath>& cache_paths) {

    be_config_data_dir_list_state.store(1, std::memory_order_release);

    Defer defer {[]() {

        be_config_data_dir_list_state.store(2, std::memory_order_release);

        be_config_data_dir_list_state.notify_all();

    }};

    for (int i = 0; i < store_paths.size(); i++) {

        DataDirInfo data_dir_info;

        data_dir_info.path = store_paths[i].path;

        data_dir_info.storage_medium = store_paths[i].storage_medium;

        data_dir_info.data_dir_type = DataDirType::OLAP_DATA_DIR;

        data_dir_info.metric_name = "local_data_dir_" + std::to_string(i);

        be_config_data_dir_list.push_back(data_dir_info);

    }

    for (int i = 0; i < spill_store_paths.size(); i++) {

        doris::DataDirInfo data_dir_info;

        data_dir_info.path = spill_store_paths[i].path;

        data_dir_info.storage_medium = spill_store_paths[i].storage_medium;

        data_dir_info.data_dir_type = doris::DataDirType::SPILL_DISK_DIR;

        data_dir_info.metric_name = "spill_data_dir_" + std::to_string(i);

        be_config_data_dir_list.push_back(data_dir_info);

    }

    for (int i = 0; i < cache_paths.size(); i++) {

        doris::DataDirInfo data_dir_info;

        data_dir_info.path = cache_paths[i].path;

        data_dir_info.storage_medium = TStorageMedium::REMOTE_CACHE;

        data_dir_info.data_dir_type = doris::DataDirType::DATA_CACHE_DIR;

        data_dir_info.metric_name = "local_cache_dir_" + std::to_string(i);

        be_config_data_dir_list.push_back(data_dir_info);

    }

    std::sort(be_config_data_dir_list.begin(), be_config_data_dir_list.end(),

              [](const DataDirInfo& a, const DataDirInfo& b) {

                  return a.path.length() > b.path.length();

              });

}

LocalFileReader::LocalFileReader(Path path, size_t file_size, int fd)

        : _fd(fd), _path(std::move(path)), _file_size(file_size) {

    _data_dir_path = "";

    BeConfDataDirReader::get_data_dir_by_file_path(&_path, &_data_dir_path);

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

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

}

LocalFileReader::~LocalFileReader() {

    WARN_IF_ERROR(close(), fmt::format("Failed to close file {}", _path.native()));

}

Status LocalFileReader::close() {

    bool expected = false;

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

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

        int res = -1;

        if (bthread_self() == 0) {

            res = ::close(_fd);

        } else {

            auto task = [&] { res = ::close(_fd); };

            AsyncIO::run_task(task, io::FileSystemType::LOCAL);

        }

        if (-1 == res) {

            std::string err = errno_to_str();

            return localfs_error(errno, fmt::format("failed to close {}", _path.native()));

        }

        _fd = -1;

    }

    return Status::OK();

}

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

                                     const IOContext* /*io_ctx*/) {

    TEST_SYNC_POINT_RETURN_WITH_VALUE("LocalFileReader::read_at_impl",

                                      Status::IOError("inject io error"));

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

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

    }

    if (offset > _file_size) {

        return Status::InternalError(

                "offset exceeds file size(offset: {}, file size: {}, path: {})", offset, _file_size,

                _path.native());

    }

    size_t bytes_req = result.size;

    char* to = result.data;

    bytes_req = std::min(bytes_req, _file_size - offset);

    *bytes_read = 0;

    LIMIT_LOCAL_SCAN_IO(get_data_dir_path(), bytes_read);

    while (bytes_req != 0) {

        auto res = SYNC_POINT_HOOK_RETURN_VALUE(::pread(_fd, to, bytes_req, offset),

                                                "LocalFileReader::pread", _fd, to);

        DBUG_EXECUTE_IF("LocalFileReader::read_at_impl.io_error", {

            auto sub_path = dp->param<std::string>("sub_path", "");

            if ((sub_path.empty() && _path.filename().compare(kTestFilePath)) ||

                (!sub_path.empty() && _path.native().find(sub_path) != std::string::npos)) {

                res = -1;

                errno = EIO;

                LOG(WARNING) << Status::IOError("debug read io error: {}", _path.native());

            }

        });

        if (UNLIKELY(-1 == res && errno != EINTR)) {

            return localfs_error(errno, fmt::format("failed to read {}", _path.native()));

        }

        if (UNLIKELY(res == 0)) {

            return Status::InternalError("cannot read from {}: unexpected EOF", _path.native());

        }

        if (res > 0) {

            to += res;

            offset += res;

            bytes_req -= res;

            *bytes_read += res;

        }

    }

    DorisMetrics::instance()->local_bytes_read_total->increment(*bytes_read);

    return Status::OK();

}

} // namespace io

} // namespace doris