/*!
 * statuses
 * Copyright(c) 2014 Jonathan Ong
 * Copyright(c) 2016 Douglas Christopher Wilson
 * MIT Licensed
 */

'use strict';

/**
 * Module dependencies.
 * @private
 */

var codes = require('./codes.json');

/**
 * Module exports.
 * @public
 */

module.exports = status;

// status code to message map
status.message = codes;

// status message (lower-case) to code map
status.code = createMessageToStatusCodeMap(codes);

// array of status codes
status.codes = createStatusCodeList(codes);

// status codes for redirects
status.redirect = {
  300: true,
  301: true,
  302: true,
  303: true,
  305: true,
  307: true,
  308: true,
};

// status codes for empty bodies
status.empty = {
  204: true,
  205: true,
  304: true,
};

// status codes for when you should retry the request
status.retry = {
  502: true,
  503: true,
  504: true,
};

/**
 * Create a map of message to status code.
 * @private
 */

function createMessageToStatusCodeMap(codes) {
  var map = {};

  Object.keys(codes).forEach(function forEachCode(code) {
    var message = codes[code];
    var status = Number(code);

    // populate map
    map[message.toLowerCase()] = status;
  });

  return map;
}

/**
 * Create a list of all status codes.
 * @private
 */

function createStatusCodeList(codes) {
  return Object.keys(codes).map(function mapCode(code) {
    return Number(code);
  });
}

/**
 * Get the status code for given message.
 * @private
 */

function getStatusCode(message) {
  var msg = message.toLowerCase();

  if (!Object.prototype.hasOwnProperty.call(status.code, msg)) {
    throw new Error('invalid status message: "' + message + '"');
  }

  return status.code[msg];
}

/**
 * Get the status message for given code.
 * @private
 */

function getStatusMessage(code) {
  if (!Object.prototype.hasOwnProperty.call(status.message, code)) {
    throw new Error('invalid status code: ' + code);
  }

  return status.message[code];
}

/**
 * Get the status code.
 *
 * Given a number, this will throw if it is not a known status
 * code, otherwise the code will be returned. Given a string,
 * the string will be parsed for a number and return the code
 * if valid, otherwise will lookup the code assuming this is
 * the status message.
 *
 * @param {string|number} code
 * @returns {number}
 * @public
 */

function status(code) {
  if (typeof code === 'number') {
    return getStatusMessage(code);
  }

  if (typeof code !== 'string') {
    throw new TypeError('code must be a number or string');
  }

  // '403'
  var n = parseInt(code, 10);
  if (!isNaN(n)) {
    return getStatusMessage(n);
  }

  return getStatusCode(code);
}