/*
 * 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 m = require('mochainon');
const _ = require('lodash');
const Bluebird = require('bluebird');
const fileExists = require('file-exists');
const fs = Bluebird.promisifyAll(require('fs'));
const tmp = require('tmp');
const imageStream = require('../../lib/image-stream/index');

const doFilesContainTheSameData = (file1, file2) => {
  return Bluebird.props({
    file1: fs.readFileAsync(file1),
    file2: fs.readFileAsync(file2)
  }).then(function(data) {
    return _.isEqual(data.file1, data.file2);
  });
};

const deleteIfExists = (file) => {
  return Bluebird.try(function() {
    if (fileExists(file)) {
      return fs.unlinkAsync(file);
    }

    return Bluebird.resolve();
  });
};

exports.expectError = function(file, errorMessage, errorDetail) {
  it('should be rejected with an error', function() {
    return imageStream.getFromFilePath(file).catch((error) => {
      m.chai.expect(error).to.be.an.instanceof(Error);
      m.chai.expect(error.message).to.equal(errorMessage);
      if (errorDetail) {
        m.chai.expect(error.description).to.contain(errorDetail);
      }
      m.chai.expect(error.description).to.be.a.string;
      m.chai.expect(error.description.length > 0).to.be.true;
    });
  });
};

exports.extractFromFilePath = function(file, image) {
  it('should be able to extract the image', function() {
    const output = tmp.tmpNameSync();

    return imageStream.getFromFilePath(file).then(function(results) {
      m.chai.expect(results.path).to.equal(file);
      m.chai.expect(_.isString(results.extension)).to.be.true;
      m.chai.expect(_.isEmpty(_.trim(results.extension))).to.be.false;

      if (!_.some([
        results.size.original === fs.statSync(file).size,
        results.size.original === fs.statSync(image).size
      ])) {
        throw new Error(`Invalid size: ${results.size.original}`);
      }

      const stream = results.stream
        .pipe(results.transform)
        .pipe(fs.createWriteStream(output));

      return new Bluebird((resolve, reject) => {
        stream.on('error', reject);
        stream.on('close', resolve);
      });
    }).then(function() {
      return doFilesContainTheSameData(image, output);
    }).then(function(areEqual) {
      m.chai.expect(areEqual).to.be.true;
    }).finally(function() {
      return deleteIfExists(output);
    });
  });
};