// 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 <fmt/format.h>

#include <rapidjson/document.h>

#include <simdjson.h> // IWYU pragma: keep

#include <sstream>

#include <string>

#include <utility>

#include <vector>

#include "common/status.h"

namespace simdjson {

namespace fallback {

namespace ondemand {

class object;

class value;

} // namespace ondemand

} // namespace fallback

} // namespace simdjson

namespace doris {

enum JsonFunctionType {

    JSON_FUN_INT = 0,

    JSON_FUN_DOUBLE,

    JSON_FUN_STRING,

    JSON_FUN_UNKNOWN //The last

};

struct JsonPath {

    std::string key;               // key of a json object

    int idx;                       // array index of a json array, -1 means not set, -2 means *

    bool is_valid;                 // true if the path is successfully parsed

    bool is_reverse_index = false; // true if the path is last index, like '$.a[LAST(1)]'

    JsonPath(std::string key_, int idx_, bool is_valid_, bool is_reverse_index_)

            : key(std::move(key_)),

              idx(idx_),

              is_valid(is_valid_),

              is_reverse_index(is_reverse_index_) {}

    JsonPath(std::string key_, int idx_, bool is_valid_)

            : JsonPath(std::move(key_), idx_, is_valid_, false) {}

    std::string to_string() const {

        std::stringstream ss;

        if (!is_valid) {

            return "INVALID";

        }

        if (!key.empty()) {

            ss << key;

        }

        if (idx == -2) {

            ss << "[*]";

        } else if (is_reverse_index) {

            if (idx > 0) {

                ss << "[last-" << idx << "]";

            } else {

                ss << "[last]";

            }

        } else if (idx > -1) {

            ss << "[" << idx << "]";

        }

        return ss.str();

    }

    std::string debug_string() const {

        return fmt::format("key:{}, idx:{}, valid:{}, is_reverse_index:{}", key, idx, is_valid,

                           is_reverse_index);

    }

};

class JsonFunctions {

public:

    /**

     * The `document` parameter must be has parsed.

     * return Value Is Array object

     * wrap_explicitly is set to true when the returned Array is wrapped actively.

     */

    static rapidjson::Value* get_json_array_from_parsed_json(

            const std::vector<JsonPath>& parsed_paths, rapidjson::Value* document,

            rapidjson::Document::AllocatorType& mem_allocator, bool* wrap_explicitly);

    // this is only for test, it will parse the json path inside,

    // so that we can easily pass a json path as string.

    static rapidjson::Value* get_json_array_from_parsed_json(

            const std::string& jsonpath, rapidjson::Value* document,

            rapidjson::Document::AllocatorType& mem_allocator, bool* wrap_explicitly);

    static rapidjson::Value* get_json_object_from_parsed_json(

            const std::vector<JsonPath>& parsed_paths, rapidjson::Value* document,

            rapidjson::Document::AllocatorType& mem_allocator);

    static void parse_json_paths(const std::string& path_strings,

                                 std::vector<JsonPath>* parsed_paths);

    // extract_from_object extracts value from object according to the json path.

    // Now, we do not support complete functions of json path.

    // Eg. city[*].id is not supported in this function

    static Status extract_from_object(simdjson::ondemand::object& obj,

                                      const std::vector<JsonPath>& jsonpath,

                                      simdjson::ondemand::value* value) noexcept;

    // src:    {"a" : "b" {"c" : 1}, "e" : 123}

    // dst:    {"a" : "b" {"d" : 1}}

    // merged: {"a" : "b" : {"c" : 1, "d" : 1}, "e" : 123}

    static void merge_objects(rapidjson::Value& dst_object, rapidjson::Value& src_object,

                              rapidjson::Document::AllocatorType& allocator);

    static std::string print_json_value(const rapidjson::Value& value);

    static bool is_root_path(const std::vector<JsonPath>& json_path);

private:

    static rapidjson::Value* match_value(const std::vector<JsonPath>& parsed_paths,

                                         rapidjson::Value* document,

                                         rapidjson::Document::AllocatorType& mem_allocator,

                                         bool is_insert_null = false);

    static void get_parsed_paths(const std::vector<std::string>& path_exprs,

                                 std::vector<JsonPath>* parsed_paths);

};

} // namespace doris