ahmadnassri/httpsnippet

/**
 * @description
 * HTTP code snippet generator for Swift using NSURLSession.
 *
 * @author
 * @thibaultCha
 *
 * for any questions or issues regarding the generated code snippet, please open an issue mentioning the author.
 */

import { CodeBuilder } from '../../../helpers/code-builder';
import { Client } from '../../targets';
import { literalDeclaration } from '../helpers';

export interface NsurlsessionOptions {
  pretty?: boolean;
  timeout?: number | string;
}

export const nsurlsession: Client<NsurlsessionOptions> = {
  info: {
    key: 'nsurlsession',
    title: 'NSURLSession',
    link: 'https://developer.apple.com/library/mac/documentation/Foundation/Reference/NSURLSession_class/index.html',
    description: "Foundation's NSURLSession request",
  },
  convert: ({ allHeaders, postData, fullUrl, method }, options) => {
    const opts = {
      indent: '  ',
      pretty: true,
      timeout: '10',
      ...options,
    };

    const { push, blank, join } = new CodeBuilder({ indent: opts.indent });

    // Markers for headers to be created as litteral objects and later be set on the NSURLRequest if exist
    const req = {
      hasHeaders: false,
      hasBody: false,
    };

    // We just want to make sure people understand that is the only dependency
    push('import Foundation');

    if (Object.keys(allHeaders).length) {
      req.hasHeaders = true;
      blank();
      push(literalDeclaration('headers', allHeaders, opts));
    }

    if (postData.text || postData.jsonObj || postData.params) {
      req.hasBody = true;

      switch (postData.mimeType) {
        case 'application/x-www-form-urlencoded':
          // By appending parameters one by one in the resulting snippet,
          // we make it easier for the user to edit it according to his or her needs after pasting.
          // The user can just add/remove lines adding/removing body parameters.
          blank();
          if (postData.params?.length) {
            const [head, ...tail] = postData.params;
            push(
              `let postData = NSMutableData(data: "${head.name}=${head.value}".data(using: String.Encoding.utf8)!)`,
            );
            tail.forEach(({ name, value }) => {
              push(`postData.append("&${name}=${value}".data(using: String.Encoding.utf8)!)`);
            });
          } else {
            req.hasBody = false;
          }
          break;

        case 'application/json':
          if (postData.jsonObj) {
            push(`${literalDeclaration('parameters', postData.jsonObj, opts)} as [String : Any]`);
            blank();

            push('let postData = JSONSerialization.data(withJSONObject: parameters, options: [])');
          }
          break;

        case 'multipart/form-data':
          /**
           * By appending multipart parameters one by one in the resulting snippet,
           * we make it easier for the user to edit it according to his or her needs after pasting.
           * The user can just edit the parameters NSDictionary or put this part of a snippet in a multipart builder method.
           */

          push(literalDeclaration('parameters', postData.params, opts));
          blank();
          push(`let boundary = "${postData.boundary}"`);
          blank();
          push('var body = ""');
          push('var error: NSError? = nil');
          push('for param in parameters {');
          push('let paramName = param["name"]!', 1);
          push('body += "--\\(boundary)\\r\\n"', 1);
          push('body += "Content-Disposition:form-data; name=\\"\\(paramName)\\""', 1);
          push('if let filename = param["fileName"] {', 1);
          push('let contentType = param["content-type"]!', 2);
          push(
            'let fileContent = String(contentsOfFile: filename, encoding: String.Encoding.utf8)',
            2,
          );
          push('if (error != nil) {', 2);
          push('print(error as Any)', 3);
          push('}', 2);
          push('body += "; filename=\\"\\(filename)\\"\\r\\n"', 2);
          push('body += "Content-Type: \\(contentType)\\r\\n\\r\\n"', 2);
          push('body += fileContent', 2);
          push('} else if let paramValue = param["value"] {', 1);
          push('body += "\\r\\n\\r\\n\\(paramValue)"', 2);
          push('}', 1);
          push('}');
          break;

        default:
          blank();
          push(
            `let postData = NSData(data: "${postData.text}".data(using: String.Encoding.utf8)!)`,
          );
      }
    }

    blank();

    // NSURLRequestUseProtocolCachePolicy is the default policy, let's just always set it to avoid confusion.
    push(`let request = NSMutableURLRequest(url: NSURL(string: "${fullUrl}")! as URL,`);
    push('                                        cachePolicy: .useProtocolCachePolicy,');
    push(
      // @ts-expect-error needs better types
      `                                    timeoutInterval: ${parseInt(opts.timeout, 10).toFixed(
        1,
      )})`,
    );
    push(`request.httpMethod = "${method}"`);

    if (req.hasHeaders) {
      push('request.allHTTPHeaderFields = headers');
    }

    if (req.hasBody) {
      push('request.httpBody = postData as Data');
    }

    blank();
    // Retrieving the shared session will be less verbose than creating a new one.

    push('let session = URLSession.shared');
    push(
      'let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in',
    );
    push('if (error != nil) {', 1);
    push('print(error as Any)', 2);
    push('} else {', 1); // Casting the NSURLResponse to NSHTTPURLResponse so the user can see the status     .
    push('let httpResponse = response as? HTTPURLResponse', 2);
    push('print(httpResponse)', 2);
    push('}', 1);
    push('})');
    blank();
    push('dataTask.resume()');

    return join();
  },
};