console-app/lib/TypeValidation/TypeValidation.ts

/*
 * Copyright (C) Sapphirecode - All Rights Reserved
 * This file is part of console-app which is released under MIT.
 * See file 'LICENSE' for full license details.
 * Created by Timo Hocker <timo@scode.ovh>, May 2020
 */

import { OptionType } from '../OptionType';

export class TypeValidation {
  private readonly _option_type: string;

  public get option_type (): OptionType {
    return this._option_type as OptionType;
  }

  public get persistent_type (): 'string'|'number'|'boolean'|'array' {
    return this.option_type as 'string'|'number'|'boolean'|'array';
  }

  public get string_type (): 'string'|'number'|'boolean'|'object' {
    const type = this.option_type;
    if (type === 'array')
      return 'object';
    return type as 'string'|'number'|'boolean';
  }

  public constructor (type: string) {
    this._option_type = type;
  }

  public validate_type (value: unknown): boolean {
    const type_match = typeof value === this.string_type;
    const array_match = this.option_type !== 'array' || Array.isArray (value);
    return type_match && array_match;
  }

  public to_type (value: unknown): Promise<unknown> {
    if (this.option_type === 'string')
      return Promise.resolve (String (value));

    if (this.option_type === 'number') {
      const as_num = parseFloat (String (value));
      if (isNaN (as_num))
        throw new Error ('value is not a number');
      return Promise.resolve (as_num);
    }

    if (this.option_type === 'int') {
      const as_num = parseInt (String (value));
      if (isNaN (as_num))
        throw new Error ('value is not a number');
      return Promise.resolve (as_num);
    }

    if (this.option_type === 'boolean') {
      const as_num = parseInt (String (value));
      if (
        as_num !== 1 && as_num !== 0
        && !(/^(?:true|false)$/iu).test (String (value))
      )
        throw new Error ('value is not a boolean');
      return Promise.resolve (
        as_num === 1 || (/true/iu).test (String (value))
      );
    }

    if (this.option_type === 'array') {
      if (typeof value === 'string') {
        return Promise.resolve (value.split (',')
          .map ((v) => v.trim ()));
      }
      if (this.validate_type (value))
        return Promise.resolve (value);
      throw new Error ('value is not an array');
    }
    throw new Error ('unknown type');
  }
}