/*
 * Copyright 2016 Resin.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

'use strict';

const imageWrite = require('etcher-image-write');
const imageStream = require('etcher-image-stream');
const Bluebird = require('bluebird');
const umount = Bluebird.promisifyAll(require('umount'));
const os = require('os');
const isWindows = os.platform() === 'win32';

if (isWindows) {

  // The `can-ignore` annotation is EncloseJS (http://enclosejs.com) specific.
  var removedrive = Bluebird.promisifyAll(require('removedrive', 'can-ignore'));

}

/**
 * @summary Write an image to a disk drive
 * @function
 * @public
 *
 * @description
 * See https://github.com/resin-io-modules/etcher-image-write for information
 * about the `state` object passed to `onProgress` callback.
 *
 * @param {String} imagePath - path to image
 * @param {Object} drive - drive
 * @param {Object} options - options
 * @param {Boolean} [options.unmountOnSuccess=false] - unmount on success
 * @param {Boolean} [options.validateWriteOnSuccess=false] - validate write on success
 * @param {Function} onProgress - on progress callback (state)
 *
 * @fulfil {Boolean} - whether the operation was successful
 * @returns {Promise}
 *
 * @example
 * writer.writeImage('path/to/image.img', {
 *   device: '/dev/disk2'
 * }, {
 *   unmountOnSuccess: true,
 *   validateWriteOnSuccess: true
 * }, function(state) {
 *   console.log(state.percentage);
 * }).then(function() {
 *   console.log('Done!');
 * });
 */
exports.writeImage = function(imagePath, drive, options, onProgress) {
  return umount.umountAsync(drive.device).then(function() {
    return imageStream.getFromFilePath(imagePath);
  }).then(function(image) {
    return imageWrite.write(drive.device, image.stream, {
      check: options.validateWriteOnSuccess,
      size: image.size,
      transform: image.transform
    });
  }).then(function(writer) {
    return new Bluebird(function(resolve, reject) {
      writer.on('progress', onProgress);
      writer.on('error', reject);
      writer.on('done', resolve);
    });
  }).tap(function() {
    if (!options.unmountOnSuccess) {
      return;
    }

    if (isWindows && drive.mountpoint) {
      return removedrive.ejectAsync(drive.mountpoint);
    }

    return umount.umountAsync(drive.device);
  });
};