import fs, {copyFileSync, mkdirSync, statSync} from 'fs';
import {join, extname} from 'path';
import multer from 'multer';
import sharp from 'sharp';
import {uid} from 'rand-token';

import Pages from './Pages';

import {getBaseUrl} from '../helpers';

import {pagination} from '../config';

const checkAndCreateDirectory = async (directory) => {
  try {
    return statSync(directory);
  } catch (err) {
    if (err.errno === -2) {
      mkdirSync(directory);
    } else {
      throw err;
    }
  }

  return true;
};

const resizeImage = async (sourceImage, destImage, w, h) => {
  return sharp(sourceImage)
      .resize(w, h, {
        fit: 'inside',
      })
      .toFile(destImage);
};

/**
 * Classe permettant la gestion des images
 */
class Uploads extends Pages {
  /**
   * @param {Object} req
   * @param {String} viewname
   */
  constructor(req, viewname) {
    super(req, viewname);

    this.upload = multer({
      storage: multer.diskStorage({}),
      fileFilter(multerReq, file, cb) {
        const filetypes = /jpeg|jpg|png/;
        const mimetype = filetypes.test(file.mimetype);
        const filExtname = filetypes.test(
            extname(file.originalname).toLowerCase(),
        );

        if (mimetype && filExtname) {
          return cb(null, true);
        }

        const error = 'Seuls les fichiers de type jpg et png sont acceptés';
        req.session.messages.push(error);
        return cb(new Error(error));
      },
    }).single('image');

    const baseUrl = getBaseUrl(req);
    this.baseUploadDir = `${__dirname}/../../uploads/`;
    this.userUploadDir = join(this.baseUploadDir, req.user._id);
    this.userUri = `${baseUrl}/uploads/${req.user._id}`;
  }

  /**
   *
   * @param {*} req
   * @param {*} callback
   */
  async postOne(req) {
    await new Promise((resolve, reject) => {
      this.upload(req, req.body, (err, data) => {
        if (err) {
          return reject(err);
        }

        resolve(data);
      });
    });

    checkAndCreateDirectory(this.baseUploadDir);
    checkAndCreateDirectory(this.userUploadDir);

    let ext = req.file.originalname.split('.');
    ext = ext[ext.length - 1];
    // eslint-disable-next-line max-len
    const uploadname = `${uid(4)}_${Buffer.from(req.file.originalname).toString('base64')}.${ext}`;
    const originalFileName = uploadname;
    const mediumFileName = `medium_${uploadname}`;
    const smallFileName = `small_${uploadname}`;

    copyFileSync(req.file.path, join(this.userUploadDir, originalFileName));

    await resizeImage(
        req.file.path,
        path.join(
            this.userUploadDir,
            mediumFileName,
        ),
        800,
        600,
    );
    await resizeImage(
        req.file.path,
        path.join(
            this.userUploadDir,
            smallFileName,
        ),
        300,
        200,
    );

    this.pageContent.page.upload = {
      originalFile: `${this.userUri}/${originalFileName}`,
      mediumFile: `${this.userUri}/${mediumFileName}`,
      smallFile: `${this.userUri}/${smallFileName}`,
    };

    return true;
  }

  /**
   * Méthode permettant d'afficher la liste des images d'un utilisateur
   * @param {Object} req
   */
  async getAll(req) {
    const currentPage = Number(req.query.page || 1);
    const startAt = (currentPage - 1) * pagination;
    const endAt = startAt + pagination;
    const listOfFiles = [];
    let total = 0;

    checkAndCreateDirectory(this.baseUploadDir);
    checkAndCreateDirectory(this.userUploadDir);

    const files = fs.readdirSync(this.userUploadDir)
        .map((v) => {
          // eslint-disable-next-line max-len
          return {name: v, time: statSync(join(this.userUploadDir, v)).mtime.getTime()};
        })
        .sort(function(a, b) {
          return b.time - a.time;
        })
        .map(function(v) {
          return v.name;
        });

    for (let i = 0; i < files.length; i += 1) {
      const file = files[i];
      if (file.indexOf('medium_') === 0) {
        total += 1;
        if (listOfFiles.length < endAt) {
          listOfFiles.push({
            originalFile: `${this.userUri}/${file.replace('medium_', '')}`,
            mediumFile: `${this.userUri}/${file}`,
            smallFile: `${this.userUri}/${file.replace('medium_', 'small_')}`,
          });
        }
      }
    }

    this.pageContent.page.images = listOfFiles.slice(startAt);
    this.pageContent.page.currentPage = currentPage;
    // eslint-disable-next-line max-len
    this.pageContent.page.totalPages = Math.floor(total / pagination) + (total % pagination > 0 ? 1 : 0);
  }
}

module.exports = Uploads;