// 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 <gen_cpp/PlanNodes_types.h>

#include <atomic>

#include <memory>

#include <mutex>

#include <string>

#include <thread>

#include <unordered_map>

#include "common/status.h"

#include "io/fs/hdfs.h"

#include "io/hdfs_util.h"

namespace doris::io {

// A manager class to handle multiple hdfsFS instances

class HdfsMgr {

public:

    HdfsMgr();

    // Get or create a hdfsFS instance based on the given parameters

    Status get_or_create_fs(const THdfsParams& hdfs_params, const std::string& fs_name,

                            std::shared_ptr<HdfsHandler>* fs_handler);

    virtual ~HdfsMgr();

protected:

    // For testing purpose

    friend class HdfsMgrTest;

    size_t get_fs_handlers_size() const { return _fs_handlers.size(); }

    bool has_fs_handler(uint64_t hash_code) const {

        return _fs_handlers.find(hash_code) != _fs_handlers.end();

    }

    void set_instance_timeout_seconds(int64_t timeout_seconds) {

        _instance_timeout_seconds = timeout_seconds;

    }

    void set_cleanup_interval_seconds(int64_t interval_seconds) {

        _cleanup_interval_seconds = interval_seconds;

    }

    uint64_t _hdfs_hash_code(const THdfsParams& hdfs_params, const std::string& fs_name);

    virtual Status _create_hdfs_fs_impl(const THdfsParams& hdfs_params, const std::string& fs_name,

                                        std::shared_ptr<HdfsHandler>* fs_handler);

private:

    HdfsMgr(const HdfsMgr&) = delete;

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

    // Start the cleanup thread

    void _start_cleanup_thread();

    // Stop the cleanup thread

    void _stop_cleanup_thread();

    // Cleanup thread function

    void _cleanup_loop();

    // Remove kerberos ticket cache if instance is using kerberos auth

    void _cleanup_kerberos_ticket(const HdfsHandler& handler);

    Status _create_hdfs_fs(const THdfsParams& hdfs_params, const std::string& fs_name,

                           std::shared_ptr<HdfsHandler>* fs_handler);

private:

    std::mutex _mutex;

    std::unordered_map<uint64_t, std::shared_ptr<HdfsHandler>> _fs_handlers;

    std::atomic<bool> _should_stop_cleanup_thread;

    std::unique_ptr<std::thread> _cleanup_thread;

    int64_t _cleanup_interval_seconds = 3600;  // Run cleanup every hour

    int64_t _instance_timeout_seconds = 86400; // 24 hours timeout

};

} // namespace doris::io