scratch-gui/src/lib/monitor-adapter.js

GraphicaL User Interface for creating and running Scratch 3.0 projects

import OpcodeLabels from './opcode-labels.js';

const isUndefined = a => typeof a === 'undefined';

/**
 * Convert monitors from VM format to what the GUI needs to render.
 * - Convert opcode to a label and a category
 * @param {string} block.id - The id of the monitor block
 * @param {string} block.spriteName - Present only if the monitor applies only to the sprite
 *     with given target ID. The name of the target sprite when the monitor was created
 * @param {string} block.opcode - The opcode of the monitor
 * @param {object} block.params - Extra params to the monitor block
 * @param {string|number|Array} block.value - The monitor value
 * @return {object} The adapted monitor with label and category
 */
export default function ({id, spriteName, opcode, params, value}) {
    let {label, category, labelFn} = OpcodeLabels(opcode);

    // Use labelFn if provided for dynamic labelling (e.g. variables)
    if (!isUndefined(labelFn)) label = labelFn(params);

    // Append sprite name for sprite-specific monitors
    if (spriteName) {
        label = `${spriteName}: ${label}`;
    }

    // If value is a number, round it to six decimal places
    if (typeof value === 'number') {
        value = Number(value.toFixed(6));
    }
    
    return {id, label, category, value};
}