pigallery2/backend/middlewares/thumbnail/ThumbnailGeneratorMWs.ts

///<reference path="../customtypings/jimp.d.ts"/>
import * as path from 'path';
import * as crypto from 'crypto';
import * as fs from 'fs';
import * as os from 'os';
import {NextFunction, Request, Response} from 'express';
import {ErrorCodes, ErrorDTO} from '../../../common/entities/Error';
import {ContentWrapper} from '../../../common/entities/ConentWrapper';
import {DirectoryDTO} from '../../../common/entities/DirectoryDTO';
import {ProjectPath} from '../../ProjectPath';
import {PhotoDTO} from '../../../common/entities/PhotoDTO';
import {Config} from '../../../common/config/private/Config';
import {ThumbnailProcessingLib} from '../../../common/config/private/IPrivateConfig';
import {ThumbnailTH} from '../../model/threading/ThreadPool';
import {RendererInput} from '../../model/threading/ThumbnailWorker';
import {ITaskQue, TaskQue} from '../../model/threading/TaskQue';


export class ThumbnailGeneratorMWs {
  private static initDone = false;
  private static taskQue: ITaskQue = null;

  public static init() {
    if (this.initDone === true) {
      return;
    }


    if (Config.Server.threading.enable === true ||
      Config.Server.thumbnail.processingLibrary !== ThumbnailProcessingLib.Jimp) {
      if (Config.Server.threading.thumbnailThreads > 0) {
        Config.Client.Thumbnail.concurrentThumbnailGenerations = Config.Server.threading.thumbnailThreads;
      } else {
        Config.Client.Thumbnail.concurrentThumbnailGenerations = Math.max(1, os.cpus().length - 1);
      }
    } else {
      Config.Client.Thumbnail.concurrentThumbnailGenerations = 1;
    }

    if (Config.Server.threading.enable === true &&
      Config.Server.thumbnail.processingLibrary === ThumbnailProcessingLib.Jimp) {
      this.taskQue = new ThumbnailTH(Config.Client.Thumbnail.concurrentThumbnailGenerations);
    } else {
      this.taskQue = new TaskQue(Config.Client.Thumbnail.concurrentThumbnailGenerations);
    }

    this.initDone = true;
  }

  public static addThumbnailInformation(req: Request, res: Response, next: NextFunction) {
    if (!req.resultPipe) {
      return next();
    }

    const cw: ContentWrapper = req.resultPipe;
    if (cw.notModified === true) {
      return next();
    }
    if (cw.directory) {
      ThumbnailGeneratorMWs.addThInfoTODir(<DirectoryDTO>cw.directory);
    }
    if (cw.searchResult) {
      ThumbnailGeneratorMWs.addThInfoToPhotos(cw.searchResult.photos);
    }


    return next();

  }

  public static generateThumbnail(req: Request, res: Response, next: NextFunction) {
    if (!req.resultPipe) {
      return next();
    }

    // load parameters
    const imagePath = req.resultPipe;
    let size: number = parseInt(req.params.size, 10) || Config.Client.Thumbnail.thumbnailSizes[0];

    // validate size
    if (Config.Client.Thumbnail.thumbnailSizes.indexOf(size) === -1) {
      size = Config.Client.Thumbnail.thumbnailSizes[0];
    }

    ThumbnailGeneratorMWs.generateImage(imagePath, size, false, req, res, next);


  }

  public static generateIcon(req: Request, res: Response, next: NextFunction) {
    if (!req.resultPipe) {
      return next();
    }

    // load parameters
    const imagePath = req.resultPipe;
    const size: number = Config.Client.Thumbnail.iconSize;
    ThumbnailGeneratorMWs.generateImage(imagePath, size, true, req, res, next);


  }

  private static addThInfoTODir(directory: DirectoryDTO) {
    if (typeof  directory.photos === 'undefined') {
      directory.photos = [];
    }
    if (typeof  directory.directories === 'undefined') {
      directory.directories = [];
    }
    ThumbnailGeneratorMWs.addThInfoToPhotos(directory.photos);

    for (let i = 0; i < directory.directories.length; i++) {
      ThumbnailGeneratorMWs.addThInfoTODir(directory.directories[i]);
    }

  }

  private static addThInfoToPhotos(photos: Array<PhotoDTO>) {
    const thumbnailFolder = ProjectPath.ThumbnailFolder;
    for (let i = 0; i < photos.length; i++) {
      const fullImagePath = path.join(ProjectPath.ImageFolder, photos[i].directory.path, photos[i].directory.name, photos[i].name);
      for (let j = 0; j < Config.Client.Thumbnail.thumbnailSizes.length; j++) {
        const size = Config.Client.Thumbnail.thumbnailSizes[j];
        const thPath = path.join(thumbnailFolder, ThumbnailGeneratorMWs.generateThumbnailName(fullImagePath, size));
        if (fs.existsSync(thPath) === true) {
          if (typeof  photos[i].readyThumbnails === 'undefined') {
            photos[i].readyThumbnails = [];
          }
          photos[i].readyThumbnails.push(size);
        }
      }
      const iconPath = path.join(thumbnailFolder,
        ThumbnailGeneratorMWs.generateThumbnailName(fullImagePath, Config.Client.Thumbnail.iconSize));
      if (fs.existsSync(iconPath) === true) {
        photos[i].readyIcon = true;
      }

    }
  }

  private static async generateImage(imagePath: string,
                                     size: number,
                                     makeSquare: boolean,
                                     req: Request, res: Response, next: NextFunction) {
    // generate thumbnail path
    const thPath = path.join(ProjectPath.ThumbnailFolder, ThumbnailGeneratorMWs.generateThumbnailName(imagePath, size));


    req.resultPipe = thPath;

    // check if thumbnail already exist
    if (fs.existsSync(thPath) === true) {
      return next();
    }

    // create thumbnail folder if not exist
    if (!fs.existsSync(ProjectPath.ThumbnailFolder)) {
      fs.mkdirSync(ProjectPath.ThumbnailFolder);
    }

    // run on other thread
    const input = <RendererInput>{
      imagePath: imagePath,
      size: size,
      thPath: thPath,
      makeSquare: makeSquare,
      qualityPriority: Config.Server.thumbnail.qualityPriority
    };
    try {
      await this.taskQue.execute(input);
      return next();
    } catch (error) {
      return next(new ErrorDTO(ErrorCodes.THUMBNAIL_GENERATION_ERROR, 'Error during generating thumbnail: ' + input.imagePath, error));
    }
  }

  private static generateThumbnailName(imagePath: string, size: number): string {
    return crypto.createHash('md5').update(imagePath).digest('hex') + '_' + size + '.jpg';
  }
}