import { mapClass } from './libvbar-m-dxmap.so'
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/**
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* In-memory Key-Value Store Module (dxMap)
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*
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* Features:
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* - Provides a topic-based, in-memory key-value storage.
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* - Thread-safe: Data can be safely accessed and modified from multiple JavaScript threads.
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* - Supports storing various data types (string, number, boolean, object, array) by automatically serializing/deserializing them.
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*
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* Usage:
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* - First, get a map instance for a specific topic using `map.get('myTopic')`.
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* - Then, use the instance's methods (`put`, `get`, `has`, `del`, etc.) to manage data within that topic.
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*
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* @example
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* import map from 'dxMap';
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*
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* // Get an instance for the 'user' topic
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* const userMap = map.get('user');
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*
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* // Put some data
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* userMap.put('name', 'John Doe');
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* userMap.put('age', 30);
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* userMap.put('isActive', true);
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* userMap.put('roles', ['admin', 'editor']);
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*
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* // Get data
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* const name = userMap.get('name'); // "John Doe"
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*
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* // Check if a key exists
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* const hasAge = userMap.has('age'); // true
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*
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* // Delete a key
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* userMap.del('isActive');
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*
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* // Get all keys for the topic
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* const allKeys = userMap.keys(); // ['name', 'age', 'roles']
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*
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* Doc/Demo: https://github.com/DejaOS/DejaOS
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*/
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const mapObj = new mapClass();
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const map = {
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/**
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* Gets a map instance for a given topic name.
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* Each topic is a separate namespace for keys.
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* @param {string} name - The name of the topic. Must not be null or empty.
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* @returns {{keys: (function(): string[]), get: (function(string): *), has: (function(string): boolean), put: (function(string, *): boolean), del: (function(string): boolean), destroy: (function(): boolean)}} An object with methods to interact with the map for the specified topic.
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* @throws {Error} If the name is null or empty.
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*/
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get: function (name) {
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if (!name || name.length == 0) {
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throw new Error("dxMap.get:name should not be null or empty")
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}
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//第一次put会自动创建实例
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return {
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/**
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* Retrieves all keys within the current topic.
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* @returns {string[]} An array of all keys for the topic. Returns an empty array if the topic is empty or does not exist.
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*/
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keys: function () {
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let all = mapObj.keys(name)
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return all == null ? [] : all
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},
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/**
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* Retrieves the value associated with a key within the current topic.
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* The returned value will be deserialized to its original type (number, boolean, object, array, or string).
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* @param {string} key - The key to retrieve. Must not be null or empty.
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* @returns {*} The value associated with the key, or `undefined` if the key does not exist.
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* @throws {Error} If the key is null or empty.
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*/
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get: function (key) {
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if (!key || key.length < 1) {
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throw new Error("The 'key' parameter cannot be null or empty")
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}
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// put空字符串，get会是null
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let value = mapObj.get(name, key)
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// C layer returns null if not found. JS layer should propagate this.
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if (value === null) {
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return undefined; // Return undefined for non-existent keys, a common JS pattern.
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}
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return _parseString(value)
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},
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/**
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* Checks if a key exists within the current topic.
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* @param {string} key - The key to check. Must not be null or empty.
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* @returns {boolean} `true` if the key exists, `false` otherwise.
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* @throws {Error} If the key is null or empty.
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*/
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has: function (key) {
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if (!key || key.length < 1) {
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throw new Error("The 'key' parameter cannot be null or empty")
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}
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return mapObj.has(name, key)
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},
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/**
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* Inserts or updates a key-value pair within the current topic.
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* The value will be automatically serialized.
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* If `value` is `null` or `undefined`, the key will be deleted.
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* @param {string} key - The key to set. Must not be null or empty.
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* @param {*} value - The value to associate with the key. Supported types: string, number, boolean, object, array. Functions are not supported.
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* @returns {boolean} Returns `true` on success.
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* @throws {Error} If the key is null or empty, or if the value is a function.
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*/
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put: function (key, value) {
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if (!key || key.length < 1) {
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throw new Error("The 'key' parameter cannot be null or empty")
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}
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// Implement "set null/undefined to delete" logic.
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if (value === null || value === undefined) {
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return mapObj.delete(name, key);
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}
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return mapObj.insert(name, key, _stringifyValue(value))
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},
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/**
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* Deletes a key-value pair from the current topic.
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* @param {string} key - The key to delete. Must not be null or empty.
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* @returns {boolean} `true` if the key was found and deleted, `false` otherwise.
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* @throws {Error} If the key is null or empty.
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*/
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del: function (key) {
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if (!key || key.length < 1) {
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throw new Error("The 'key' parameter cannot be null or empty")
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}
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return mapObj.delete(name, key)
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},
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/**
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* Destroys the entire topic, deleting all its keys and freeing associated memory.
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* After calling destroy, the instance should not be used anymore.
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* @returns {boolean} Returns `true` on success.
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*/
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destroy: function () {
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return mapObj.destroy(name)
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},
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}
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}
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}
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/**
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* Serializes a value into a string with a type prefix.
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* @private
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* @param {*} value - The value to serialize.
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* @returns {string} The serialized string.
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*/
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function _stringifyValue(value) {
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const type = typeof value
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if (type === 'string') {
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return value
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}
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if (type === 'number') {
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return '#n#' + value
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}
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if (type === 'boolean') {
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return '#b#' + value
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}
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if (type === 'object') {
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// 如果是对象，进一步判断是否为数组
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if (Array.isArray(value)) {
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return '#a#' + JSON.stringify(value);
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}// else if (value === null) { 前面已经规避了null的情况
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return '#o#' + JSON.stringify(value)
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}
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if (type === 'function') {
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throw new Error("The 'value' parameter should not be function")
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}
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}
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/**
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* Deserializes a string with a type prefix back to its original value.
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* @private
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* @param {string} str - The string to deserialize.
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* @returns {*} The deserialized value.
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*/
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function _parseString(str) {
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if (str.startsWith('#n#')) {
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// 解析数字
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const numberStr = str.substring(3);
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return numberStr.includes('.') ? parseFloat(numberStr) : parseInt(numberStr, 10);
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} else if (str.startsWith('#b#')) {
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// 解析布尔值
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return str.substring(3) === 'true';
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} else if (str.startsWith('#a#')) {
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// 解析数组
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return JSON.parse(str.substring(3));
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} else if (str.startsWith('#o#')) {
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// 解析对象
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return JSON.parse(str.substring(3));
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} else {
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// 默认情况下，将字符串返回
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return str;
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}
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}
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export default map;
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