ckeditor/ckeditor5-core

/**
 * @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */

/**
 * @module core/commandcollection
 */

import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror';

/**
 * Collection of commands. Its instance is available in {@link module:core/editor/editor~Editor#commands `editor.commands`}.
 */
export default class CommandCollection {
    /**
     * Creates collection instance.
     */
    constructor() {
        /**
         * Command map.
         *
         * @private
         * @member {Map}
         */
        this._commands = new Map();
    }

    /**
     * Registers a new command.
     *
     * @param {String} commandName The name of the command.
     * @param {module:core/command~Command} command
     */
    add( commandName, command ) {
        this._commands.set( commandName, command );
    }

    /**
     * Retrieves a command from the collection.
     *
     * @param {String} commandName The name of the command.
     * @returns {module:core/command~Command}
     */
    get( commandName ) {
        return this._commands.get( commandName );
    }

    /**
     * Executes a command.
     *
     * @param {String} commandName The name of the command.
     * @param {*} [...commandParams] Command parameters.
     */
    execute( commandName, ...args ) {
        const command = this.get( commandName );

        if ( !command ) {
            /**
             * Command does not exist.
             *
             * @error commandcollection-command-not-found
             * @param {String} commandName Name of the command.
             */
            throw new CKEditorError( 'commandcollection-command-not-found: Command does not exist.', this, { commandName } );
        }

        command.execute( ...args );
    }

    /**
     * Returns iterator of command names.
     *
     * @returns {Iterable.<String>}
     */
    * names() {
        yield* this._commands.keys();
    }

    /**
     * Returns iterator of command instances.
     *
     * @returns {Iterable.<module:core/command~Command>}
     */
    * commands() {
        yield* this._commands.values();
    }

    /**
     * Iterable interface.
     *
     * Returns `[ commandName, commandInstance ]` pairs.
     *
     * @returns {Iterable.<Array>}
     */
    [ Symbol.iterator ]() {
        return this._commands[ Symbol.iterator ]();
    }

    /**
     * Destroys all collection commands.
     */
    destroy() {
        for ( const command of this.commands() ) {
            command.destroy();
        }
    }
}