import type { NodeDef } from '../../NodeRegistry';
import { asNumber, asString } from '../../values';
import { int, str } from '../shared';

export const Substring: NodeDef = {
  type: 'Substring',
  label: 'Substring',
  category: 'data',
  description:
    'A part of a text: "count" characters starting at "start" (the first is 0). ' +
    'A negative count reaches to the end.',
  inputs: [str('text'), int('start'), int('count', -1)],
  outputs: [str('text')],
  params: [],
  run: (_ctx, inputs) => {
    const text = asString(inputs.text);
    const start = Math.max(0, Math.floor(asNumber(inputs.start)));
    const count = Math.floor(asNumber(inputs.count));
    return { outputs: { text: count < 0 ? text.slice(start) : text.slice(start, start + count) } };
  },
};