pigallery2/backend/model/DiskManger.ts

import * as fs from "fs";
import * as path from "path";
import * as mime from "mime";
import * as  iptc from "node-iptc";
import * as  exif_parser from "exif-parser";
import {Directory} from "../../common/entities/Directory";
import {
    Photo,
    PhotoMetadata,
    ImageSize,
    CameraMetadata,
    PositionMetaData,
    GPSMetadata
} from "../../common/entities/Photo";

export class DiskManager {
    public static scanDirectory(relativeDirectoryName, cb:(error:any, result:Directory) => void) {
        console.log("DiskManager: scanDirectory");
        let directoryName = path.basename(relativeDirectoryName);
        let directoryParent = path.join(path.dirname(relativeDirectoryName), "/");
        let absoluteDirectoryName = path.join(__dirname, "/../../demo/images", relativeDirectoryName);

        let directory = new Directory(1, directoryName, directoryParent, new Date(), [], []);

        let promises:Array< Promise<any> > = [];
        fs.readdir(absoluteDirectoryName, function (err, list) {

            if (err) {
                return cb(err, null);
            }


            for (let i = 0; i < list.length; i++) {
                let file = list[i];
                let fullFilePath = path.resolve(absoluteDirectoryName, file);
                if (fs.statSync(fullFilePath).isDirectory()) {
                    directory.directories.push(new Directory(2, file, relativeDirectoryName, new Date(), [], []));
                }

                if (DiskManager.isImage(fullFilePath)) {


                    let promise = DiskManager.loadPhotoMetadata(fullFilePath).then((photoMetadata)=> {
                        directory.photos.push(new Photo(1, file, directory, photoMetadata));
                    });

                    promises.push(promise);
                }
            }

            Promise.all(promises).then(()=> {
                return cb(err, directory);
            });

        });
    }

    private static isImage(fullPath) {
        let imageMimeTypes = [
            'image/bmp',
            'image/gif',
            'image/jpeg',
            'image/png',
            'image/pjpeg',
            'image/tiff',
            'image/webp',
            'image/x-tiff',
            'image/x-windows-bmp'
        ];

        var extension = mime.lookup(fullPath);

        if (imageMimeTypes.indexOf(extension) !== -1) {
            return true;
        }

        return false;
    }


    private static loadPhotoMetadata(fullPath):Promise<PhotoMetadata> {
        return new Promise<PhotoMetadata>((resolve:(metadata:PhotoMetadata)=>void, reject) => {
            fs.readFile(fullPath, function (err, data) {
                if (err) {
                    reject(err);
                } else {
                    let exif = exif_parser.create(data).parse();
                    let iptcData = iptc(data);

                    let imageSize:ImageSize = {width: exif.imageSize.width, height: exif.imageSize.height};
                    let cameraData:CameraMetadata = {
                        ISO: exif.tags.ISO,
                        model: exif.tags.Modeol,
                        maker: exif.tags.Make,
                        fStop: exif.tags.FNumber,
                        exposure: exif.tags.ExposureTime,
                        focalLength: exif.tags.FocalLength,
                        lens: exif.tags.LensModel,
                    };
                    let GPS:GPSMetadata = {
                        latitude: exif.tags.GPSLatitude,
                        longitude: exif.tags.GPSLongitude,
                        altitude: exif.tags.GPSAltitude

                    };

                    let positionData:PositionMetaData = {
                        GPSData: GPS,
                        country: iptcData.country_or_primary_location_name,
                        state: iptcData.province_or_state,
                        city: iptcData.city
                    };

                    let keywords:[string] = iptcData.keywords;
                    let creationDate:Date = iptcData.date_time;


                    let metadata:PhotoMetadata = new PhotoMetadata(keywords, cameraData, positionData, imageSize, creationDate);
                    resolve(metadata);
                }
            });
        });


    }
}