// 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.

// This file is copied from

// https://github.com/ClickHouse/ClickHouse/blob/master/src/Interpreters/Cache/FileCache_fwd.h

// and modified by Doris

#include "io/cache/file_cache_common.h"

#include "common/config.h"

#include "exec/common/hex.h"

#include "io/cache/block_file_cache.h"

namespace doris::io {

std::string cache_type_to_surfix(FileCacheType type) {

    switch (type) {

    case FileCacheType::INDEX:

        return "_idx";

    case FileCacheType::DISPOSABLE:

        return "_disposable";

    case FileCacheType::NORMAL:

        return "";

    case FileCacheType::TTL:

        return "_ttl";

    }

    return "";

}

FileCacheType surfix_to_cache_type(const std::string& str) {

    if (str == "idx") {

        return FileCacheType::INDEX;

    } else if (str == "disposable") {

        return FileCacheType::DISPOSABLE;

    } else if (str == "ttl") {

        return FileCacheType::TTL;

    }

    DCHECK(false) << "The string is " << str;

    return FileCacheType::DISPOSABLE;

}

FileCacheType string_to_cache_type(const std::string& str) {

    if (str == "normal") {

        return FileCacheType::NORMAL;

    } else if (str == "index") {

        return FileCacheType::INDEX;

    } else if (str == "disposable") {

        return FileCacheType::DISPOSABLE;

    } else if (str == "ttl") {

        return FileCacheType::TTL;

    }

    DCHECK(false) << "The string is " << str;

    return FileCacheType::NORMAL;

}

std::string cache_type_to_string(FileCacheType type) {

    switch (type) {

    case FileCacheType::INDEX:

        return "index";

    case FileCacheType::DISPOSABLE:

        return "disposable";

    case FileCacheType::NORMAL:

        return "normal";

    case FileCacheType::TTL:

        return "ttl";

    }

    DCHECK(false) << "unknown type: " << type;

    return "normal";

}

std::string FileCacheSettings::to_string() const {

    std::stringstream ss;

    ss << "capacity: " << capacity << ", max_file_block_size: " << max_file_block_size

       << ", max_query_cache_size: " << max_query_cache_size

       << ", disposable_queue_size: " << disposable_queue_size

       << ", disposable_queue_elements: " << disposable_queue_elements

       << ", index_queue_size: " << index_queue_size

       << ", index_queue_elements: " << index_queue_elements

       << ", ttl_queue_size: " << ttl_queue_size << ", ttl_queue_elements: " << ttl_queue_elements

       << ", query_queue_size: " << query_queue_size

       << ", query_queue_elements: " << query_queue_elements << ", storage: " << storage;

    return ss.str();

}

FileCacheSettings get_file_cache_settings(size_t capacity, size_t max_query_cache_size,

                                          size_t normal_percent, size_t disposable_percent,

                                          size_t index_percent, size_t ttl_percent,

                                          const std::string& storage) {

    io::FileCacheSettings settings;

    if (capacity == 0) {

        return settings;

    }

    settings.capacity = capacity;

    settings.max_file_block_size = config::file_cache_each_block_size;

    settings.max_query_cache_size = max_query_cache_size;

    size_t per_size = settings.capacity / 100;

    settings.disposable_queue_size = per_size * disposable_percent;

    settings.disposable_queue_elements =

            std::max(settings.disposable_queue_size / settings.max_file_block_size,

                     REMOTE_FS_OBJECTS_CACHE_DEFAULT_ELEMENTS);

    settings.index_queue_size = per_size * index_percent;

    settings.index_queue_elements =

            std::max(settings.index_queue_size / settings.max_file_block_size,

                     REMOTE_FS_OBJECTS_CACHE_DEFAULT_ELEMENTS);

    settings.ttl_queue_size = per_size * ttl_percent;

    settings.ttl_queue_elements = std::max(settings.ttl_queue_size / settings.max_file_block_size,

                                           REMOTE_FS_OBJECTS_CACHE_DEFAULT_ELEMENTS);

    settings.query_queue_size = settings.capacity - settings.disposable_queue_size -

                                settings.index_queue_size - settings.ttl_queue_size;

    settings.query_queue_elements =

            std::max(settings.query_queue_size / settings.max_file_block_size,

                     REMOTE_FS_OBJECTS_CACHE_DEFAULT_ELEMENTS);

    settings.storage = storage;

    return settings;

}

std::string UInt128Wrapper::to_string() const {

    return get_hex_uint_lowercase(value_);

}

FileBlocksHolderPtr FileCacheAllocatorBuilder::allocate_cache_holder(size_t offset, size_t size,

                                                                     int64_t tablet_id) const {

    CacheContext ctx;

    ctx.cache_type = _expiration_time == 0 ? FileCacheType::NORMAL : FileCacheType::TTL;

    ctx.expiration_time = _expiration_time;

    ctx.is_cold_data = _is_cold_data;

    ctx.tablet_id = tablet_id;

    ReadStatistics stats;

    ctx.stats = &stats;

    auto holder = _cache->get_or_set(_cache_hash, offset, size, ctx);

    return std::make_unique<FileBlocksHolder>(std::move(holder));

}

template size_t LRUQueue::get_capacity(std::lock_guard<std::mutex>& cache_lock) const;

template void LRUQueue::remove(Iterator queue_it, std::lock_guard<std::mutex>& cache_lock);

std::string FileCacheInfo::to_string() const {

    std::stringstream ss;

    ss << "Hash: " << hash.to_string() << "\n"

       << "Expiration Time: " << expiration_time << "\n"

       << "Offset: " << offset << "\n"

       << "Cache Type: " << cache_type_to_string(cache_type) << "\n";

    return ss.str();

}

std::string InconsistencyType::to_string() const {

    std::string result = "Inconsistency Reason: ";

    if (type == NONE) {

        result += "NONE";

    } else {

        if (type & NOT_LOADED) {

            result += "NOT_LOADED ";

        }

        if (type & MISSING_IN_STORAGE) {

            result += "MISSING_IN_STORAGE ";

        }

        if (type & SIZE_INCONSISTENT) {

            result += "SIZE_INCONSISTENT ";

        }

        if (type & CACHE_TYPE_INCONSISTENT) {

            result += "CACHE_TYPE_INCONSISTENT ";

        }

        if (type & EXPIRATION_TIME_INCONSISTENT) {

            result += "EXPIRATION_TIME_INCONSISTENT ";

        }

        if (type & TMP_FILE_EXPECT_DOWNLOADING_STATE) {

            result += "TMP_FILE_EXPECT_DOWNLOADING_STATE";

        }

    }

    result += "\n";

    return result;

}

std::optional<int64_t> get_tablet_id(std::string file_path) {

    // Expected path formats:

    // support both .dat and .idx file extensions

    // support formate see ut. storage_resource_test:StorageResourceTest.ParseTabletIdFromPath

    if (file_path.empty()) {

        return std::nullopt;

    }

    // Find the position of "data/" in the path

    std::string_view path_view = file_path;

    std::string_view data_prefix = DATA_PREFIX;

    size_t data_pos = path_view.find(data_prefix);

    if (data_pos == std::string_view::npos) {

        return std::nullopt;

    }

    if (data_prefix.length() + data_pos >= path_view.length()) {

        return std::nullopt;

    }

    // Extract the part after "data/"

    path_view = path_view.substr(data_pos + data_prefix.length() + 1);

    // Check if path ends with .dat or .idx

    if (!path_view.ends_with(".dat") && !path_view.ends_with(".idx")) {

        return std::nullopt;

    }

    // Count slashes in the remaining path

    size_t slash_count = 0;

    for (char c : path_view) {

        if (c == '/') {

            slash_count++;

        }

    }

    // Split path by '/'

    std::vector<std::string_view> parts;

    size_t start = 0;

    size_t pos = 0;

    while ((pos = path_view.find('/', start)) != std::string_view::npos) {

        if (pos > start) {

            parts.push_back(path_view.substr(start, pos - start));

        }

        start = pos + 1;

    }

    if (start < path_view.length()) {

        parts.push_back(path_view.substr(start));

    }

    if (parts.empty()) {

        return std::nullopt;

    }

    // Determine path version based on slash count and extract tablet_id

    // Version 0: {tablet_id}/{rowset_id}_{seg_id}.dat (1 slash)

    // Version 1: {shard}/{tablet_id}/{rowset_id}/{seg_id}.dat (3 slashes)

    if (slash_count == 1) {

        // Version 0 format: parts[0] should be tablet_id

        if (parts.size() >= 1) {

            try {

                int64_t tablet_id = std::stoll(std::string(parts[0]));

                return tablet_id;

            } catch (const std::exception&) {

                // Not a valid number, return nullopt at last

            }

        }

    } else if (slash_count == 3) {

        // Version 1 format: parts[1] should be tablet_id (parts[0] is shard)

        if (parts.size() >= 2) {

            try {

                int64_t tablet_id = std::stoll(std::string(parts[1]));

                return tablet_id;

            } catch (const std::exception&) {

                // Not a valid number, return nullopt at last

            }

        }

    }

    return std::nullopt;

}

} // namespace doris::io