// 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 <rocksdb/iterator.h>

#include <functional>

#include <memory>

#include <string>

#include <vector>

#include "common/status.h"

namespace rocksdb {

class ColumnFamilyHandle;

class DB;

class WriteBatch;

} // namespace rocksdb

namespace doris {

class OlapMeta final {

public:

    struct BatchEntry {

        const std::string& key;

        const std::string& value;

        BatchEntry(const std::string& key_arg, const std::string& value_arg)

                : key(key_arg), value(value_arg) {}

    };

    OlapMeta(const std::string& root_path);

    ~OlapMeta();

    Status init();

    Status get(const int column_family_index, const std::string& key, std::string* value);

    bool key_may_exist(const int column_family_index, const std::string& key, std::string* value);

    Status put(const int column_family_index, const std::string& key, const std::string& value);

    Status put(const int column_family_index, const std::vector<BatchEntry>& entries);

    Status put(rocksdb::WriteBatch* batch);

    Status remove(const int column_family_index, const std::string& key);

    Status remove(const int column_family_index, const std::vector<std::string>& keys);

    Status iterate(const int column_family_index, const std::string& prefix,

                   std::function<bool(const std::string&, const std::string&)> const& func);

    Status iterate(const int column_family_index, const std::string& seek_key,

                   const std::string& prefix,

                   std::function<bool(const std::string&, const std::string&)> const& func);

    [[nodiscard]] std::string get_root_path() const { return _root_path; }

    rocksdb::ColumnFamilyHandle* get_handle(const int column_family_index) {

        return _handles[column_family_index].get();

    }

private:

    Status get_iterator(const int column_family_index, const std::string& seek_key,

                        const std::string& prefix, rocksdb::Iterator*);

    std::string _root_path;

    // keep order of _db && _handles, we need destroy _handles before _db

    std::unique_ptr<rocksdb::DB, std::function<void(rocksdb::DB*)>> _db;

    std::vector<std::unique_ptr<rocksdb::ColumnFamilyHandle>> _handles;

};

} // namespace doris