Is this un-readable?

if_statement.js

/**
 * OAuth request message skeleton for every request.
 * before the final url is generated, it must be run through
 * the oauth Timestamp & Signature generators
 *
 * @constructor
 */
sd.OAuth2.AuthMessage = function(code) {
    if (code !== undefined) {
        this.parameters = {};
        if(code == 'refresh_token'){
            this.parameters['refresh_token'] = sd.Prefs.get('refresh_token');
            this.parameters['grant_type'] = 'refresh_token';
        } else{
            this.parameters['code'] = code;
            this.parameters['grant_type'] = 'authorization_code';
        }
        this.parameters['client_id'] = sd.OAuth2.application_key;
        this.parameters['client_secret'] = sd.OAuth2.application_key_secret;
        this.parameters['redirect_uri'] = sd.OAuth2.close_url;
        
        this.action = sd.OAuth2.token_url;
        this.method = 'POST';
    } else {
        this.parameters = {
            response_type: 'code',
            client_id: sd.OAuth2.application_key,
            redirect_uri: sd.OAuth2.close_url};
        this.action = sd.OAuth2.authorize_url;
        this.method = 'GET';
    }
};

nested_ternary.js

/**
 * OAuth request message skeleton for every request.
 * before the final url is generated, it must be run through
 * the oauth Timestamp & Signature generators
 *
 * @constructor
 */
sd.OAuth2.AuthMessage = function(code) {
    var missing_code = (code === undefined);
    
    this.parameters = missing_code
        ? { response_type: 'code', 
            client_id: sd.OAuth2.application_key, 
            redirect_uri: sd.OAuth2.close_url } 
        : (code == 'refresh_token') 
                ? { refresh_token: sd.Prefs.get('refresh_token'),
                    grant_type: 'refresh_token',
                    client_id: sd.OAuth2.application_key,
                    client_secret: sd.OAuth2.application_key_secret,
                    redirect_uri: sd.OAuth2.close_url } 
                : { code: code,
                    grant_type: 'authorization_code',
                    client_id: sd.OAuth2.application_key,
                    client_secret: sd.OAuth2.application_key_secret,
                    redirect_uri: sd.OAuth2.close_url };
    
    this.action = missing_code ? sd.OAuth2.authorize_url : sd.OAuth2.token_url;
    this.method = missing_code ? 'GET' : 'POST'
};

single_line_ternary.js

/**
 * OAuth request message skeleton for every request.
 * before the final url is generated, it must be run through
 * the oauth Timestamp & Signature generators
 *
 * @constructor
 */
sd.OAuth2.AuthMessage = function(code) {
    var missing_code = (code === undefined);
    
    this.parameters = missing_code ? { response_type: 'code', client_id: sd.OAuth2.application_key, redirect_uri: sd.OAuth2.close_url } : (code == 'refresh_token') ? { refresh_token: sd.Prefs.get('refresh_token'), grant_type: 'refresh_token', client_id: sd.OAuth2.application_key, client_secret: sd.OAuth2.application_key_secret, redirect_uri: sd.OAuth2.close_url } : { code: code, grant_type: 'authorization_code', client_id: sd.OAuth2.application_key, client_secret: sd.OAuth2.application_key_secret, redirect_uri: sd.OAuth2.close_url };
    
    this.action = missing_code ? sd.OAuth2.authorize_url : sd.OAuth2.token_url;
    this.method = missing_code ? 'GET' : 'POST'
};

CoffeeScript

sd.OAuth2.AuthMessage = (code) ->
  if code?
    if code is "refresh_token"
      @parameters['refresh_token'] = sd.Prefs.get('refresh_token')
      @paramaters['grant_token'] = 'refresh_token'
      @parameters =
        code: code,
        grant_type: 'authorization_code',
        client_id: sd.OAuth2.application_key,
        client_secret: sd.OAuth2.application_key_secret,
        redirect_uri: sd.OAuth2.close_url
      @action = sd.OAuth2.token_url
      @method = 'POST'
  else
    @parameters =
      response_type: 'code',
      client_id: sd.OAuth2.application_key,
      redirect_uri: sd.OAuth2.close_url
    @action = sd.OAuth2.authorize_url
    @method = 'GET'

I've updated the if statement to be more correct. Want to update your coffeescript?