/*!
 * Copyright (c) 2020 Ville de Montreal. All rights reserved.
 * Licensed under the MIT license.
 * See LICENSE file in the project root for full license information.
 */

import { ISerializer } from './ISerializer';

export class FormSerializer implements ISerializer {
  /**
   * returns a serialized object, either as a string or as a Buffer,
   * depending on the kind of data beeing serialized.
   * @param data the Javascript object to serialize
   */
  public serialize(data: unknown): string | Buffer {
    if (data === undefined || data === null) {
      return '';
    }
    if (typeof data === 'string') {
      return data;
    }
    if (data instanceof Buffer) {
      return data;
    }
    let form: URLSearchParams;
    if (data instanceof URLSearchParams) {
      form = data;
    } else {
      form = new URLSearchParams();
      for (const [k, v] of Object.entries(data as any)) {
        let textVal = '';
        if (v) {
          textVal = (v as any).toString();
        }
        form.append(k, textVal);
      }
    }
    return form.toString();
  }

  /**
   * returns the deserialized Javascript object from the received HTTP response's body
   * (either as a text or as a buffer)
   * @param data the HTTP response's body to deserialize
   */
  public deserialize(data: string | Buffer) {
    const result: any = {};
    if (data) {
      const text = data instanceof Buffer ? data.toString() : (data as string);
      for (const [k, v] of new URLSearchParams(text)) {
        result[k] = v;
      }
    }
    return result;
  }
}