'use strict';

const { BaseClient, common_header_errors, error_factory } = require('./common');
const { ResponseError } = require('./exceptions');
const directory_pb = require('../bosdyn/api/directory_pb');
const directory_service_pb_grpc = require('../bosdyn/api/directory_service_grpc_pb');

class DirectoryResponseError extends ResponseError {
  constructor(msg) {
    super(null, msg);
    this.name = 'DirectoryResponseError';
  }
}

class NonexistentServiceError extends DirectoryResponseError {
  constructor(msg) {
    super(msg);
    this.name = 'NonexistentServiceError';
  }
}

const _STATUS_TO_ERROR = {
  [directory_pb.GetServiceEntryResponse.Status.STATUS_OK]: [null, null],
  [directory_pb.GetServiceEntryResponse.Status.STATUS_NONEXISTENT_SERVICE]: [
    NonexistentServiceError,
    'The requested service name does not exist.',
  ],
};

function _error_from_response(response) {
  return error_factory(
    response,
    response.getStatus(),
    Object.keys(directory_pb.GetServiceEntryResponse.Status),
    _STATUS_TO_ERROR,
  );
}

function _list_value(response) {
  return response.getServiceEntriesList();
}

function _get_entry_value(response) {
  return response.getServiceEntry();
}

/**
 * List robot services and get information on them.
 * @class DirectoryClient
 * @extends BaseClient
 */
class DirectoryClient extends BaseClient {
  static default_service_name = 'directory';
  static service_type = 'bosdyn.api.DirectoryService';

  /**
   * Create an instance of DirectoryClient's class.
   * @param {string} [name=null] Name of the Class.
   */
  constructor(name = null) {
    super(directory_service_pb_grpc.DirectoryServiceClient, name);
  }

  /**
   * List all services present on the robot.
   * @param {Object} args Extra arguments for controlling RPC details.
   * @returns {Promise<Array>} A list of the proto message definitions of all registered services
   * @throws {RpcError} Problem communicating with the robot.
   */
  list(args) {
    const req = new directory_pb.ListServiceEntriesRequest();
    return this.call(this._stub.listServiceEntries, req, _list_value, common_header_errors, args);
  }

  /**
   * Get the service entry for one particular service specified by name.
   * @param {string} service_name The name of the service to retrieve.
   * @param {Object} args Extra arguments for controlling RPC details.
   * @returns {Promise<directory_pb.GetServiceEntryResponse>} The proto message definition of the service entry
   * @throws {RpcError} Problem communicating with the robot.
   * @throws {NonexistentServiceError} The service was not found.
   * @throws {DirectoryResponseError} Something went wrong during the directory access.
   */
  get_entry(service_name, args) {
    const req = new directory_pb.GetServiceEntryRequest().setServiceName(service_name);
    return this.call(this._stub.getServiceEntry, req, _get_entry_value, _error_from_response, args);
  }
}

module.exports = {
  DirectoryResponseError,
  NonexistentServiceError,
  DirectoryClient,
};