// 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 <glog/logging.h>

#include <stddef.h>

#include <boost/uuid/random_generator.hpp>

#include <boost/uuid/uuid_io.hpp>

#include <memory>

#include <string>

#include <utility>

#include "common/status.h"

#include "vec/aggregate_functions/aggregate_function.h"

#include "vec/columns/column_string.h"

#include "vec/common/string_utils/string_utils.h"

#include "vec/core/block.h"

#include "vec/core/column_numbers.h"

#include "vec/core/types.h"

#include "vec/data_types/data_type_string.h"

#include "vec/functions/function.h"

#include "vec/functions/function_totype.h"

#include "vec/functions/simple_function_factory.h"

namespace doris {

class FunctionContext;

} // namespace doris

namespace doris::vectorized {

class Uuid : public IFunction {

public:

    static constexpr auto name = "uuid";

    static constexpr size_t uuid_length = 36; //uuid fixed length

    static FunctionPtr create() { return std::make_shared<Uuid>(); }

    String get_name() const override { return name; }

    bool use_default_implementation_for_constants() const override { return false; }

    size_t get_number_of_arguments() const override { return 0; }

    bool is_variadic() const override { return false; }

    DataTypePtr get_return_type_impl(const DataTypes& arguments) const override {

        return std::make_shared<DataTypeString>();

    }

    Status execute_impl(FunctionContext* context, Block& block, const ColumnNumbers& arguments,

                        uint32_t result, size_t input_rows_count) const override {

        auto col_res = ColumnString::create();

        col_res->get_offsets().reserve(input_rows_count);

        col_res->get_chars().reserve(input_rows_count * uuid_length);

        boost::uuids::random_generator generator;

        for (int i = 0; i < input_rows_count; i++) {

            std::string uuid = boost::uuids::to_string(generator());

            DCHECK(uuid.length() == uuid_length);

            col_res->insert_data_without_reserve(uuid.c_str(), uuid.length());

        }

        block.replace_by_position(result, std::move(col_res));

        return Status::OK();

    }

};

struct NameIsUuid {

    static constexpr auto name = "is_uuid";

};

struct IsUuidImpl {

    using ReturnType = DataTypeBool;

    using ReturnColumnType = ColumnUInt8;

    static constexpr auto PrimitiveTypeImpl = PrimitiveType::TYPE_STRING;

    static constexpr size_t uuid_without_dash_length = 32;

    static constexpr size_t uuid_with_dash_length = 36;

    static constexpr size_t uuid_with_braces_and_dash_length = 38;

    static constexpr size_t dash_positions[4] = {8, 13, 18, 23};

    static bool is_uuid_with_dash(const char* src, const char* end) {

        size_t str_size = end - src;

        for (int i = 0; i < str_size; ++i) {

            if (!is_hex_ascii(src[i])) {

                if (i == dash_positions[0] || i == dash_positions[1] || i == dash_positions[2] ||

                    i == dash_positions[3]) {

                    if (src[i] != '-') {

                        return false;

                    }

                } else {

                    return false;

                }

            }

        }

        return true;

    }

    static Status vector(const ColumnString::Chars& data, const ColumnString::Offsets& offsets,

                         PaddedPODArray<UInt8>& res) {

        size_t rows_count = offsets.size();

        res.resize(rows_count);

        for (size_t i = 0; i < rows_count; ++i) {

            const char* source = reinterpret_cast<const char*>(&data[offsets[i - 1]]);

            int str_size = offsets[i] - offsets[i - 1];

            if (str_size == uuid_without_dash_length) {

                bool is_valid = true;

                for (int j = 0; j < str_size; ++j) {

                    if (!is_hex_ascii(source[j])) {

                        is_valid = false;

                        break;

                    }

                }

                res[i] = is_valid;

            } else if (str_size == uuid_with_dash_length) {

                res[i] = is_uuid_with_dash(source, source + str_size);

            } else if (str_size == uuid_with_braces_and_dash_length) {

                if (source[0] != '{' || source[str_size - 1] != '}') {

                    res[i] = 0;

                    continue;

                }

                res[i] = is_uuid_with_dash(source + 1, source + str_size - 1);

            } else {

                res[i] = 0;

            }

        }

        return Status::OK();

    }

};

using FunctionIsUuid = FunctionUnaryToType<IsUuidImpl, NameIsUuid>;

void register_function_uuid(SimpleFunctionFactory& factory) {

    factory.register_function<Uuid>();

    factory.register_function<FunctionIsUuid>();

}

} // namespace doris::vectorized