// 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 "exec/spill/spill_file_manager.h"

#include <fmt/format.h>

#include <glog/logging.h>

#include <algorithm>

#include <filesystem>

#include <memory>

#include <string>

#include "common/logging.h"

#include "common/metrics/doris_metrics.h"

#include "exec/spill/spill_file.h"

#include "io/fs/file_system.h"

#include "io/fs/local_file_system.h"

#include "storage/olap_define.h"

#include "util/parse_util.h"

#include "util/pretty_printer.h"

#include "util/time.h"

namespace doris {

SpillFileManager::~SpillFileManager() {

    DorisMetrics::instance()->metric_registry()->deregister_entity(_entity);

}

SpillFileManager::SpillFileManager(

        std::unordered_map<std::string, std::unique_ptr<SpillDataDir>>&& spill_store_map)

        : _spill_store_map(std::move(spill_store_map)), _stop_background_threads_latch(1) {}

Status SpillFileManager::init() {

    LOG(INFO) << "init spill stream manager";

    RETURN_IF_ERROR(_init_spill_store_map());

    for (const auto& [path, store] : _spill_store_map) {

        auto gc_dir_root_dir = store->get_spill_data_gc_path();

        bool exists = true;

        RETURN_IF_ERROR(io::global_local_filesystem()->exists(gc_dir_root_dir, &exists));

        if (!exists) {

            RETURN_IF_ERROR(io::global_local_filesystem()->create_directory(gc_dir_root_dir));

        }

        auto spill_dir = store->get_spill_data_path();

        RETURN_IF_ERROR(io::global_local_filesystem()->exists(spill_dir, &exists));

        if (!exists) {

            RETURN_IF_ERROR(io::global_local_filesystem()->create_directory(spill_dir));

        } else {

            auto suffix = ToStringFromUnixMillis(UnixMillis());

            auto gc_dir = store->get_spill_data_gc_path(suffix);

            if (std::filesystem::exists(gc_dir)) {

                LOG(WARNING) << "gc dir already exists: " << gc_dir;

            }

            (void)io::global_local_filesystem()->rename(spill_dir, gc_dir);

            RETURN_IF_ERROR(io::global_local_filesystem()->create_directory(spill_dir));

        }

    }

    RETURN_IF_ERROR(Thread::create(

            "Spill", "spill_gc_thread", [this]() { this->_spill_gc_thread_callback(); },

            &_spill_gc_thread));

    LOG(INFO) << "spill gc thread started";

    _init_metrics();

    return Status::OK();

}

void SpillFileManager::_init_metrics() {

    _entity = DorisMetrics::instance()->metric_registry()->register_entity("spill",

                                                                           {{"name", "spill"}});

    _spill_write_bytes_metric = std::make_unique<doris::MetricPrototype>(

            doris::MetricType::COUNTER, doris::MetricUnit::BYTES, "spill_write_bytes");

    _spill_write_bytes_counter = (IntAtomicCounter*)(_entity->register_metric<IntAtomicCounter>(

            _spill_write_bytes_metric.get()));

    _spill_read_bytes_metric = std::make_unique<doris::MetricPrototype>(

            doris::MetricType::COUNTER, doris::MetricUnit::BYTES, "spill_read_bytes");

    _spill_read_bytes_counter = (IntAtomicCounter*)(_entity->register_metric<IntAtomicCounter>(

            _spill_read_bytes_metric.get()));

}

// clean up stale spilled files

void SpillFileManager::_spill_gc_thread_callback() {

    while (!_stop_background_threads_latch.wait_for(

            std::chrono::milliseconds(config::spill_gc_interval_ms))) {

        gc(config::spill_gc_work_time_ms);

        for (auto& [path, dir] : _spill_store_map) {

            static_cast<void>(dir->update_capacity());

        }

    }

}

Status SpillFileManager::_init_spill_store_map() {

    for (const auto& store : _spill_store_map) {

        RETURN_IF_ERROR(store.second->init());

    }

    return Status::OK();

}

std::vector<SpillDataDir*> SpillFileManager::_get_stores_for_spill(

        TStorageMedium::type storage_medium) {

    std::vector<std::pair<SpillDataDir*, double>> stores_with_usage;

    for (auto& [_, store] : _spill_store_map) {

        if (store->storage_medium() == storage_medium && !store->reach_capacity_limit(0)) {

            stores_with_usage.emplace_back(store.get(), store->_get_disk_usage(0));

        }

    }

    if (stores_with_usage.empty()) {

        return {};

    }

    std::ranges::sort(stores_with_usage, [](auto&& a, auto&& b) { return a.second < b.second; });

    std::vector<SpillDataDir*> stores;

    for (const auto& [store, _] : stores_with_usage) {

        stores.emplace_back(store);

    }

    return stores;

}

Status SpillFileManager::create_spill_file(const std::string& relative_path,

                                           SpillFileSPtr& spill_file) {

    auto data_dirs = _get_stores_for_spill(TStorageMedium::type::SSD);

    if (data_dirs.empty()) {

        data_dirs = _get_stores_for_spill(TStorageMedium::type::HDD);

    }

    if (data_dirs.empty()) {

        return Status::Error<ErrorCode::NO_AVAILABLE_ROOT_PATH>(

                "no available disk can be used for spill.");

    }

    // Select the first available data dir (sorted by usage ascending)

    SpillDataDir* data_dir = data_dirs.front();

    spill_file = std::make_shared<SpillFile>(data_dir, relative_path);

    return Status::OK();

}

void SpillFileManager::delete_spill_file(SpillFileSPtr spill_file) {

    if (!spill_file) {

        LOG(WARNING) << "[spill][delete] null spill_file";

        return;

    }

    spill_file->gc();

}

void SpillFileManager::gc(int32_t max_work_time_ms) {

    bool exists = true;

    bool has_work = false;

    int64_t max_work_time_ns = max_work_time_ms * 1000L * 1000L;

    MonotonicStopWatch watch;

    watch.start();

    Defer defer {[&]() {

        if (has_work) {

            std::string msg(

                    fmt::format("spill gc time: {}",

                                PrettyPrinter::print(watch.elapsed_time(), TUnit::TIME_NS)));

            msg += ", spill storage:\n";

            for (const auto& [path, store_dir] : _spill_store_map) {

                msg += "    " + store_dir->debug_string();

                msg += "\n";

            }

            LOG(INFO) << msg;

        }

    }};

    for (const auto& [path, store_dir] : _spill_store_map) {

        std::string gc_root_dir = store_dir->get_spill_data_gc_path();

        std::error_code ec;

        exists = std::filesystem::exists(gc_root_dir, ec);

        if (ec || !exists) {

            continue;

        }

        // dirs of queries

        std::vector<io::FileInfo> dirs;

        auto st = io::global_local_filesystem()->list(gc_root_dir, false, &dirs, &exists);

        if (!st.ok()) {

            continue;

        }

        for (const auto& dir : dirs) {

            has_work = true;

            if (dir.is_file) {

                continue;

            }

            std::string abs_dir = fmt::format("{}/{}", gc_root_dir, dir.file_name);

            // operator spill sub dirs of a query

            std::vector<io::FileInfo> files;

            st = io::global_local_filesystem()->list(abs_dir, false, &files, &exists);

            if (!st.ok()) {

                continue;

            }

            if (files.empty()) {

                static_cast<void>(io::global_local_filesystem()->delete_directory(abs_dir));

                continue;

            }

            for (const auto& file : files) {

                auto abs_file_path = fmt::format("{}/{}", abs_dir, file.file_name);

                if (file.is_file) {

                    static_cast<void>(io::global_local_filesystem()->delete_file(abs_file_path));

                } else {

                    static_cast<void>(

                            io::global_local_filesystem()->delete_directory(abs_file_path));

                }

                if (watch.elapsed_time() > max_work_time_ns) {

                    break;

                }

            }

        }

    }

}

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_capacity, MetricUnit::BYTES);

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_limit, MetricUnit::BYTES);

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_avail_capacity, MetricUnit::BYTES);

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_data_size, MetricUnit::BYTES);

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_has_spill_data, MetricUnit::BYTES);

DEFINE_GAUGE_METRIC_PROTOTYPE_2ARG(spill_disk_has_spill_gc_data, MetricUnit::BYTES);

SpillDataDir::SpillDataDir(std::string path, int64_t capacity_bytes,

                           TStorageMedium::type storage_medium)

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

          _disk_capacity_bytes(capacity_bytes),

          _storage_medium(storage_medium) {

    spill_data_dir_metric_entity = DorisMetrics::instance()->metric_registry()->register_entity(

            std::string("spill_data_dir.") + _path, {{"path", _path + "/" + SPILL_DIR_PREFIX}});

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_capacity);

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_limit);

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_avail_capacity);

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_data_size);

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_has_spill_data);

    INT_GAUGE_METRIC_REGISTER(spill_data_dir_metric_entity, spill_disk_has_spill_gc_data);

}

bool is_directory_empty(const std::filesystem::path& dir) {

    try {

        return std::filesystem::is_directory(dir) &&

               std::filesystem::directory_iterator(dir) ==

                       std::filesystem::end(std::filesystem::directory_iterator {});

        // this method is not thread safe, the file referenced by directory_iterator

        // maybe moved to spill_gc dir during this function call, so need to catch expection

    } catch (const std::filesystem::filesystem_error&) {

        return true;

    }

}

Status SpillDataDir::init() {

    bool exists = false;

    RETURN_IF_ERROR(io::global_local_filesystem()->exists(_path, &exists));

    if (!exists) {

        RETURN_NOT_OK_STATUS_WITH_WARN(Status::IOError("opendir failed, path={}", _path),

                                       "check file exist failed");

    }

    RETURN_IF_ERROR(update_capacity());

    LOG(INFO) << fmt::format(

            "spill storage path: {}, capacity: {}, limit: {}, available: "

            "{}",

            _path, PrettyPrinter::print_bytes(_disk_capacity_bytes),

            PrettyPrinter::print_bytes(_spill_data_limit_bytes),

            PrettyPrinter::print_bytes(_available_bytes));

    return Status::OK();

}

std::string SpillDataDir::get_spill_data_path(const std::string& query_id) const {

    auto dir = fmt::format("{}/{}", _path, SPILL_DIR_PREFIX);

    if (!query_id.empty()) {

        dir = fmt::format("{}/{}", dir, query_id);

    }

    return dir;

}

std::string SpillDataDir::get_spill_data_gc_path(const std::string& sub_dir_name) const {

    auto dir = fmt::format("{}/{}", _path, SPILL_GC_DIR_PREFIX);

    if (!sub_dir_name.empty()) {

        dir = fmt::format("{}/{}", dir, sub_dir_name);

    }

    return dir;

}

Status SpillDataDir::update_capacity() {

    std::lock_guard<std::mutex> l(_mutex);

    RETURN_IF_ERROR(io::global_local_filesystem()->get_space_info(_path, &_disk_capacity_bytes,

                                                                  &_available_bytes));

    spill_disk_capacity->set_value(_disk_capacity_bytes);

    spill_disk_avail_capacity->set_value(_available_bytes);

    auto disk_use_max_bytes =

            (int64_t)(_disk_capacity_bytes * config::storage_flood_stage_usage_percent / 100);

    bool is_percent = true;

    _spill_data_limit_bytes = ParseUtil::parse_mem_spec(config::spill_storage_limit, -1,

                                                        _disk_capacity_bytes, &is_percent);

    if (_spill_data_limit_bytes <= 0) {

        spill_disk_limit->set_value(_spill_data_limit_bytes);

        auto err_msg = fmt::format("Failed to parse spill storage limit from '{}'",

                                   config::spill_storage_limit);

        LOG(WARNING) << err_msg;

        return Status::InvalidArgument(err_msg);

    }

    if (is_percent) {

        _spill_data_limit_bytes = (int64_t)(_spill_data_limit_bytes *

                                            config::storage_flood_stage_usage_percent / 100);

    }

    _spill_data_limit_bytes = std::min(_spill_data_limit_bytes, disk_use_max_bytes);

    spill_disk_limit->set_value(_spill_data_limit_bytes);

    std::string spill_root_dir = get_spill_data_path();

    std::string spill_gc_root_dir = get_spill_data_gc_path();

    spill_disk_has_spill_data->set_value(is_directory_empty(spill_root_dir) ? 0 : 1);

    spill_disk_has_spill_gc_data->set_value(is_directory_empty(spill_gc_root_dir) ? 0 : 1);

    return Status::OK();

}

bool SpillDataDir::_reach_disk_capacity_limit(int64_t incoming_data_size) {

    double used_pct = _get_disk_usage(incoming_data_size);

    int64_t left_bytes = _available_bytes - incoming_data_size;

    if (used_pct >= config::storage_flood_stage_usage_percent / 100.0 &&

        left_bytes <= config::storage_flood_stage_left_capacity_bytes) {

        LOG(WARNING) << "reach capacity limit. used pct: " << used_pct

                     << ", left bytes: " << left_bytes << ", path: " << _path;

        return true;

    }

    return false;

}

bool SpillDataDir::reach_capacity_limit(int64_t incoming_data_size) {

    std::lock_guard<std::mutex> l(_mutex);

    if (_reach_disk_capacity_limit(incoming_data_size)) {

        return true;

    }

    if (_spill_data_bytes + incoming_data_size > _spill_data_limit_bytes) {

        LOG_EVERY_T(WARNING, 1) << fmt::format(

                "spill data reach limit, path: {}, capacity: {}, limit: {}, used: {}, "

                "available: "

                "{}, "

                "incoming "

                "bytes: {}",

                _path, PrettyPrinter::print_bytes(_disk_capacity_bytes),

                PrettyPrinter::print_bytes(_spill_data_limit_bytes),

                PrettyPrinter::print_bytes(_spill_data_bytes),

                PrettyPrinter::print_bytes(_available_bytes),

                PrettyPrinter::print_bytes(incoming_data_size));

        return true;

    }

    return false;

}

std::string SpillDataDir::debug_string() {

    return fmt::format(

            "path: {}, capacity: {}, limit: {}, used: {}, available: "

            "{}",

            _path, PrettyPrinter::print_bytes(_disk_capacity_bytes),

            PrettyPrinter::print_bytes(_spill_data_limit_bytes),

            PrettyPrinter::print_bytes(_spill_data_bytes),

            PrettyPrinter::print_bytes(_available_bytes));

}

} // namespace doris