hongaar/bandersnatch

import { Argv, PositionalOptions } from "yargs";
import { BaseArg, BaseArgOptions } from "./baseArg.js";

// We ignore some not-so-common use cases from the type to make using this
// library easier. They could still be used at runtime but won't be documented
// here.
type IgnoreOptions =
  | "array"
  | "conflicts"
  | "demandOption"
  | "desc"
  | "describe"
  | "implies"
  | "normalize";

export interface ArgumentOptions
  extends Omit<PositionalOptions, IgnoreOptions>,
    BaseArgOptions {
  optional?: true;
  variadic?: true;
}

export function argument(name: string, options?: ArgumentOptions) {
  return new Argument(name, options);
}

export const defaultOptions: ArgumentOptions = { type: "string" };

export class Argument extends BaseArg {
  protected options: ArgumentOptions = {};

  constructor(name: string, options?: ArgumentOptions) {
    super(name);

    this.configure(options || {});
  }

  configure(options: ArgumentOptions) {
    this.options = { type: "string", ...options };

    if (this.isPromptable()) {
      this.options = { optional: true, ...this.options };
    }

    return this;
  }

  isOptional() {
    return this.options.optional;
  }

  isVariadic() {
    return this.options.variadic;
  }

  /**
   * Returns the formatted positional argument to be used in a command. See
   * https://github.com/yargs/yargs/blob/master/docs/advanced.md#positional-arguments
   */
  toCommand() {
    if (this.isVariadic()) {
      return `[${this.name}..]`;
    }
    if (this.isOptional()) {
      return `[${this.name}]`;
    }
    return `<${this.name}>`;
  }

  /**
   * Calls the positional() method on the passed in yargs instance and returns
   * it. See http://yargs.js.org/docs/#api-positionalkey-opt
   */
  toYargs<T>(yargs: Argv<T>) {
    return yargs.positional(this.name, BaseArg.getYargsOptions(this.options));
  }
}