/* * Copyright (C) 2019-2021 Yomichan Authors * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <https://www.gnu.org/licenses/>. */ /** * Converts an `Error` object to a serializable JSON object. * @param error An error object to convert. * @returns A simple object which can be serialized by `JSON.stringify()`. */ function serializeError(error) { try { if (typeof error === 'object' && error !== null) { const result = { name: error.name, message: error.message, stack: error.stack }; if (Object.prototype.hasOwnProperty.call(error, 'data')) { result.data = error.data; } return result; } } catch (e) { // NOP } return { value: error, hasValue: true }; } /** * Converts a serialized erorr into a standard `Error` object. * @param serializedError A simple object which was initially generated by serializeError. * @returns A new `Error` instance. */ function deserializeError(serializedError) { if (serializedError.hasValue) { return serializedError.value; } const error = new Error(serializedError.message); error.name = serializedError.name; error.stack = serializedError.stack; if (Object.prototype.hasOwnProperty.call(serializedError, 'data')) { error.data = serializedError.data; } return error; } /** * Checks whether a given value is a non-array object. * @param value The value to check. * @returns `true` if the value is an object and not an array, `false` otherwise. */ function isObject(value) { return typeof value === 'object' && value !== null && !Array.isArray(value); } /** * Converts any string into a form that can be passed into the RegExp constructor. * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions * @param string The string to convert to a valid regular expression. * @returns The escaped string. */ function escapeRegExp(string) { return string.replace(/[.*+\-?^${}()|[\]\\]/g, '\\$&'); } /** * Reverses a string. * @param string The string to reverse. * @returns The returned string, which retains proper UTF-16 surrogate pair order. */ function stringReverse(string) { return [...string].reverse().join(''); } /** * Creates a deep clone of an object or value. This is similar to `JSON.parse(JSON.stringify(value))`. * @param value The value to clone. * @returns A new clone of the value. * @throws An error if the value is circular and cannot be cloned. */ const clone = (() => { // eslint-disable-next-line no-shadow function clone(value) { if (value === null) { return null; } switch (typeof value) { case 'boolean': case 'number': case 'string': case 'bigint': case 'symbol': case 'undefined': return value; default: return cloneInternal(value, new Set()); } } function cloneInternal(value, visited) { if (value === null) { return null; } switch (typeof value) { case 'boolean': case 'number': case 'string': case 'bigint': case 'symbol': case 'undefined': return value; case 'function': return cloneObject(value, visited); case 'object': return Array.isArray(value) ? cloneArray(value, visited) : cloneObject(value, visited); } } function cloneArray(value, visited) { if (visited.has(value)) { throw new Error('Circular'); } try { visited.add(value); const result = []; for (const item of value) { result.push(cloneInternal(item, visited)); } return result; } finally { visited.delete(value); } } function cloneObject(value, visited) { if (visited.has(value)) { throw new Error('Circular'); } try { visited.add(value); const result = {}; for (const key in value) { if (Object.prototype.hasOwnProperty.call(value, key)) { result[key] = cloneInternal(value[key], visited); } } return result; } finally { visited.delete(value); } } return clone; })(); /** * Checks if an object or value is deeply equal to another object or value. * @param value1 The first value to check. * @param value2 The second value to check. * @returns `true` if the values are the same object, or deeply equal without cycles. `false` otherwise. */ const deepEqual = (() => { // eslint-disable-next-line no-shadow function deepEqual(value1, value2) { if (value1 === value2) { return true; } const type = typeof value1; if (typeof value2 !== type) { return false; } switch (type) { case 'object': case 'function': return deepEqualInternal(value1, value2, new Set()); default: return false; } } function deepEqualInternal(value1, value2, visited1) { if (value1 === value2) { return true; } const type = typeof value1; if (typeof value2 !== type) { return false; } switch (type) { case 'object': case 'function': { if (value1 === null || value2 === null) { return false; } const array = Array.isArray(value1); if (array !== Array.isArray(value2)) { return false; } if (visited1.has(value1)) { return false; } visited1.add(value1); return array ? areArraysEqual(value1, value2, visited1) : areObjectsEqual(value1, value2, visited1); } default: return false; } } function areObjectsEqual(value1, value2, visited1) { const keys1 = Object.keys(value1); const keys2 = Object.keys(value2); if (keys1.length !== keys2.length) { return false; } const keys1Set = new Set(keys1); for (const key of keys2) { if (!keys1Set.has(key) || !deepEqualInternal(value1[key], value2[key], visited1)) { return false; } } return true; } function areArraysEqual(value1, value2, visited1) { const length = value1.length; if (length !== value2.length) { return false; } for (let i = 0; i < length; ++i) { if (!deepEqualInternal(value1[i], value2[i], visited1)) { return false; } } return true; } return deepEqual; })(); /** * Creates a new base-16 (lower case) string of a sequence of random bytes of the given length. * @param length The number of bytes the string represents. The returned string's length will be twice as long. * @returns A string of random characters. */ function generateId(length) { const array = new Uint8Array(length); crypto.getRandomValues(array); let id = ''; for (const value of array) { id += value.toString(16).padStart(2, '0'); } return id; } /** * Creates an unresolved promise that can be resolved later, outside the promise's executor function. * @returns An object `{promise, resolve, reject}`, containing the promise and the resolve/reject functions. */ function deferPromise() { let resolve; let reject; const promise = new Promise((resolve2, reject2) => { resolve = resolve2; reject = reject2; }); return {promise, resolve, reject}; } /** * Creates a promise that is resolved after a set delay. * @param delay How many milliseconds until the promise should be resolved. If 0, the promise is immediately resolved. * @param resolveValue Optional; the value returned when the promise is resolved. * @returns A promise with two additional properties: `resolve` and `reject`, which can be used to complete the promise early. */ function promiseTimeout(delay, resolveValue) { if (delay <= 0) { const promise = Promise.resolve(resolveValue); promise.resolve = () => {}; // NOP promise.reject = () => {}; // NOP return promise; } let timer = null; let {promise, resolve, reject} = deferPromise(); const complete = (callback, value) => { if (callback === null) { return; } if (timer !== null) { clearTimeout(timer); timer = null; } resolve = null; reject = null; callback(value); }; const resolveWrapper = (value) => complete(resolve, value); const rejectWrapper = (value) => complete(reject, value); timer = setTimeout(() => { timer = null; resolveWrapper(resolveValue); }, delay); promise.resolve = resolveWrapper; promise.reject = rejectWrapper; return promise; } /** * Creates a promise that will resolve after the next animation frame, using `requestAnimationFrame`. * @param timeout Optional; a maximum duration (in milliseconds) to wait until the promise resolves. If null or omitted, no timeout is used. * @returns A promise that is resolved with `{time, timeout}`, where `time` is the timestamp from `requestAnimationFrame`, * and `timeout` is a boolean indicating whether the cause was a timeout or not. * @throws The promise throws an error if animation is not supported in this context, such as in a service worker. */ function promiseAnimationFrame(timeout=null) { return new Promise((resolve, reject) => { if (typeof cancelAnimationFrame !== 'function' || typeof requestAnimationFrame !== 'function') { reject(new Error('Animation not supported in this context')); return; } let timer = null; let frameRequest = null; const onFrame = (time) => { frameRequest = null; if (timer !== null) { clearTimeout(timer); timer = null; } resolve({time, timeout: false}); }; const onTimeout = () => { timer = null; if (frameRequest !== null) { // eslint-disable-next-line no-undef cancelAnimationFrame(frameRequest); frameRequest = null; } resolve({time: performance.now(), timeout: true}); }; // eslint-disable-next-line no-undef frameRequest = requestAnimationFrame(onFrame); if (typeof timeout === 'number') { timer = setTimeout(onTimeout, timeout); } }); } /** * Invokes a standard message handler. This function is used to react and respond * to communication messages within the extension. * @param handler A handler function which is passed `params` and `...extraArgs` as arguments. * @param async Whether or not the handler is async or not. Values include `false`, `true`, or `'dynamic'`. * When the value is `'dynamic'`, the handler should return an object of the format `{async: boolean, result: any}`. * @param params Information which was passed with the original message. * @param callback A callback function which is invoked after the handler has completed. The value passed * to the function is in the format: * * `{result: any}` if the handler invoked successfully. * * `{error: object}` if the handler thew an error. The error is serialized. * @param extraArgs Additional arguments which are passed to the `handler` function. * @returns `true` if the function is invoked asynchronously, `false` otherwise. */ function invokeMessageHandler({handler, async}, params, callback, ...extraArgs) { try { let promiseOrResult = handler(params, ...extraArgs); if (async === 'dynamic') { ({async, result: promiseOrResult} = promiseOrResult); } if (async) { promiseOrResult.then( (result) => { callback({result}); }, (error) => { callback({error: serializeError(error)}); } ); return true; } else { callback({result: promiseOrResult}); return false; } } catch (error) { callback({error: serializeError(error)}); return false; } } /** * Base class controls basic event dispatching. */ class EventDispatcher { /** * Creates a new instance. */ constructor() { this._eventMap = new Map(); } /** * Triggers an event with the given name and specified argument. * @param eventName The string representing the event's name. * @param details Optional; the argument passed to the callback functions. * @returns `true` if any callbacks were registered, `false` otherwise. */ trigger(eventName, details) { const callbacks = this._eventMap.get(eventName); if (typeof callbacks === 'undefined') { return false; } for (const callback of callbacks) { callback(details); } return true; } /** * Adds a single event listener to a specific event. * @param eventName The string representing the event's name. * @param callback The event listener callback to add. */ on(eventName, callback) { let callbacks = this._eventMap.get(eventName); if (typeof callbacks === 'undefined') { callbacks = []; this._eventMap.set(eventName, callbacks); } callbacks.push(callback); } /** * Removes a single event listener from a specific event. * @param eventName The string representing the event's name. * @param callback The event listener callback to add. * @returns `true` if the callback was removed, `false` otherwise. */ off(eventName, callback) { const callbacks = this._eventMap.get(eventName); if (typeof callbacks === 'undefined') { return false; } const ii = callbacks.length; for (let i = 0; i < ii; ++i) { if (callbacks[i] === callback) { callbacks.splice(i, 1); if (callbacks.length === 0) { this._eventMap.delete(eventName); } return true; } } return false; } /** * Checks if an event has any listeners. * @param eventName The string representing the event's name. * @returns `true` if the event has listeners, `false` otherwise. */ hasListeners(eventName) { const callbacks = this._eventMap.get(eventName); return (typeof callbacks !== 'undefined' && callbacks.length > 0); } } /** * Class which stores event listeners added to various objects, making it easy to remove them in bulk. */ class EventListenerCollection { /** * Creates a new instance. */ constructor() { this._eventListeners = []; } /** * Returns the number of event listeners that are currently in the object. * @returns The number of event listeners that are currently in the object. */ get size() { return this._eventListeners.length; } /** * Adds an event listener of a generic type. * @param type The type of event listener, which can be 'addEventListener', 'addListener', or 'on'. * @param object The object to add the event listener to. * @param args The argument array passed to the object's event listener adding function. * @throws An error if type is not an expected value. */ addGeneric(type, object, ...args) { switch (type) { case 'addEventListener': return this.addEventListener(object, ...args); case 'addListener': return this.addListener(object, ...args); case 'on': return this.on(object, ...args); default: throw new Error(`Invalid type: ${type}`); } } /** * Adds an event listener using `object.addEventListener`. The listener will later be removed using `object.removeEventListener`. * @param object The object to add the event listener to. * @param args The argument array passed to the `addEventListener`/`removeEventListener` functions. */ addEventListener(object, ...args) { object.addEventListener(...args); this._eventListeners.push(['removeEventListener', object, ...args]); } /** * Adds an event listener using `object.addListener`. The listener will later be removed using `object.removeListener`. * @param object The object to add the event listener to. * @param args The argument array passed to the `addListener`/`removeListener` function. */ addListener(object, ...args) { object.addListener(...args); this._eventListeners.push(['removeListener', object, ...args]); } /** * Adds an event listener using `object.on`. The listener will later be removed using `object.off`. * @param object The object to add the event listener to. * @param args The argument array passed to the `on`/`off` function. */ on(object, ...args) { object.on(...args); this._eventListeners.push(['off', object, ...args]); } /** * Removes all event listeners added to objects for this instance and clears the internal list of event listeners. */ removeAllEventListeners() { if (this._eventListeners.length === 0) { return; } for (const [removeFunctionName, object, ...args] of this._eventListeners) { switch (removeFunctionName) { case 'removeEventListener': object.removeEventListener(...args); break; case 'removeListener': object.removeListener(...args); break; case 'off': object.off(...args); break; default: throw new Error(`Unknown remove function: ${removeFunctionName}`); } } this._eventListeners = []; } } /** * Class representing a generic value with an override stack. * Changes can be observed by listening to the 'change' event. */ class DynamicProperty extends EventDispatcher { /** * Creates a new instance with the specified value. * @param value The value to assign. */ constructor(value) { super(); this._value = value; this._defaultValue = value; this._overrides = []; } /** * Gets the default value for the property, which is assigned to the * public value property when no overrides are present. */ get defaultValue() { return this._defaultValue; } /** * Assigns the default value for the property. If no overrides are present * and if the value is different than the current default value, * the 'change' event will be triggered. * @param value The value to assign. */ set defaultValue(value) { this._defaultValue = value; if (this._overrides.length === 0) { this._updateValue(); } } /** * Gets the current value for the property, taking any overrides into account. */ get value() { return this._value; } /** * Gets the number of overrides added to the property. */ get overrideCount() { return this._overrides.length; } /** * Adds an override value with the specified priority to the override stack. * Values with higher priority will take precedence over those with lower. * For tie breaks, the override value added first will take precedence. * If the newly added override has the highest priority of all overrides * and if the override value is different from the current value, * the 'change' event will be fired. * @param value The override value to assign. * @param priority The priority value to use, as a number. * @returns A string token which can be passed to the clearOverride function * to remove the override. */ setOverride(value, priority=0) { const overridesCount = this._overrides.length; let i = 0; for (; i < overridesCount; ++i) { if (priority > this._overrides[i].priority) { break; } } const token = generateId(16); this._overrides.splice(i, 0, {value, priority, token}); if (i === 0) { this._updateValue(); } return token; } /** * Removes a specific override value. If the removed override * had the highest priority, and the new value is different from * the previous value, the 'change' event will be fired. * @param token The token for the corresponding override which is to be removed. * @returns true if an override was returned, false otherwise. */ clearOverride(token) { for (let i = 0, ii = this._overrides.length; i < ii; ++i) { if (this._overrides[i].token === token) { this._overrides.splice(i, 1); if (i === 0) { this._updateValue(); } return true; } } return false; } /** * Updates the current value using the current overrides and default value. * If the new value differs from the previous value, the 'change' event will be fired. */ _updateValue() { const value = this._overrides.length > 0 ? this._overrides[0].value : this._defaultValue; if (this._value === value) { return; } this._value = value; this.trigger('change', {value}); } } /** * This class handles logging of messages to the console and triggering * an event for log calls. */ class Logger extends EventDispatcher { /** * Creates a new instance. */ constructor() { super(); this._extensionName = 'Yomichan'; try { const {name, version} = chrome.runtime.getManifest(); this._extensionName = `${name} ${version}`; } catch (e) { // NOP } } /** * Logs a generic error. This will trigger the 'log' event with the same arguments as the function invocation. * @param error The error to log. This is typically an `Error` or `Error`-like object. * @param level The level to log at. Values include `'info'`, `'debug'`, `'warn'`, and `'error'`. * Other values will be logged at a non-error level. * @param context An optional context object for the error which should typically include a `url` field. */ log(error, level, context=null) { if (!isObject(context)) { context = {url: location.href}; } let errorString; try { if (typeof error === 'string') { errorString = error; } else { errorString = error.toString(); if (/^\[object \w+\]$/.test(errorString)) { errorString = JSON.stringify(error); } } } catch (e) { errorString = `${error}`; } let errorStack; try { errorStack = (typeof error.stack === 'string' ? error.stack.trimRight() : ''); } catch (e) { errorStack = ''; } let errorData; try { errorData = error.data; } catch (e) { // NOP } if (errorStack.startsWith(errorString)) { errorString = errorStack; } else if (errorStack.length > 0) { errorString += `\n${errorStack}`; } let message = `${this._extensionName} has encountered a problem.`; message += `\nOriginating URL: ${context.url}\n`; message += errorString; if (typeof errorData !== 'undefined') { message += `\nData: ${JSON.stringify(errorData, null, 4)}`; } message += '\n\nIssues can be reported at https://github.com/FooSoft/yomichan/issues'; switch (level) { case 'info': console.info(message); break; case 'debug': console.debug(message); break; case 'warn': console.warn(message); break; case 'error': console.error(message); break; default: console.log(message); break; } this.trigger('log', {error, level, context}); } /** * Logs a warning. This function invokes `log` internally. * @param error The error to log. This is typically an `Error` or `Error`-like object. * @param context An optional context object for the error which should typically include a `url` field. */ warn(error, context=null) { this.log(error, 'warn', context); } /** * Logs an error. This function invokes `log` internally. * @param error The error to log. This is typically an `Error` or `Error`-like object. * @param context An optional context object for the error which should typically include a `url` field. */ error(error, context=null) { this.log(error, 'error', context); } } /** * This object is the default logger used by the runtime. */ const log = new Logger();