scanner.js

"use strict";

const fs = require("fs");
const mm = require("music-metadata");
const sqlite3 = require("sqlite3");
const db = new sqlite3.Database("db/metadata.sqlite");

function getArtistId(artist) {
  if (!artist) {
    return 1;
  }

  artist = artist.trim();
  return new Promise((resolve) => {
    db.get(
      "SELECT id FROM artist WHERE name = ? COLLATE NOCASE",
      [artist],
      (err, row) => {
        if (err) {
          console.error(err);
        } else {
          if (row) {
            resolve(row.id);
          } else {
            db.run("INSERT INTO artist (name) VALUES(?)", [artist], (err) => {
              console.log("Added artist:", artist);
              resolve(getArtistId(artist));
            });
          }
        }
      }
    );
  });
}

function getAlbumId(artist, album, year) {
  if (!album || album === "") {
    return 1;
  }
  album = album.trim();
  const uniqname = `${artist}_${album}_${year}`.toUpperCase();

  return new Promise((resolve) => {
    db.get(
      "SELECT id FROM album WHERE uniqname = ?",
      [uniqname],
      (err, row) => {
        if (err) {
          console.error(err);
        } else {
          if (row) {
            resolve(row.id);
          } else {
            db.run(
              "INSERT INTO album (name, uniqname) VALUES(?, ?)",
              [album, uniqname],
              (err) => {
                console.log("Added album:", uniqname);
                resolve(getAlbumId(artist, album, year));
              }
            );
          }
        }
      }
    );
  });
}

function addFile(file, next) {
  (async () => {
    let metadata;
    try {
      metadata = await mm.parseFile(file);
    } catch (e) {
      console.log("Metadata extract failed, adding anyway..");
    }

    let artistId = 1;
    let year = 0;
    let title = file;
    let track = 0;
    let disk = 0;
    let codec = "-";
    let bitrate = 0;
    let duration = 0;
    let lossless = 0;
    let albumId = 1;
    let genre = 0;

    try {
      const common = metadata.common;
      const format = metadata.format;
      artistId = await getArtistId(common.artist);
      year = common.year;
      title = common.title;
      track = common.track.no;
      disk = common.disk.no;
      codec = format.codec;
      bitrate = format.bitrate;
      duration = format.duration;
      lossless = format.lossless ? 1 : 0;
      albumId = await getAlbumId(artistId, common.album, year);
      genre = common.genre.join(",");
    } catch (e) {}

    db.run(
      "INSERT INTO track (file, artist, album, year, title, track, disk, codec, bitrate, duration, lossless, genre) VALUES(?,?,?,?,?,?,?,?,?,?,?,?)",
      [
        file,
        artistId,
        albumId,
        year,
        title,
        track,
        disk,
        codec,
        bitrate,
        duration,
        lossless,
        genre,
      ],
      (err) => {
        if (err) {
          console.error("Error inserting " + file);
          console.error(err);
        }
        next();
      }
    );
  })();
}

let files = 0,
  dirs = 0;

const filesToAdd = [];

function scan(dir) {
  const ents = fs.readdirSync(dir, { withFileTypes: true });
  ents.forEach((ent) => {
    if (ent.isDirectory()) {
      scan(dir + "/" + ent.name);
      dirs++;
    }
    if (ent.isFile()) {
      const file = ent.name;
      if (file.match(/\.mp3$|\.wav$|\.ogg$|\.flac$|\.mp2$|\.wma$|\.m4a$/i)) {
        files++;
        filesToAdd.push({ fileName: dir + "/" + file, inDb: false });
      }
    }
  });
}

function addFromArr(idx, done) {
  if (idx < filesToAdd.length) {
    const { fileName, inDb } = filesToAdd[idx];
    if (!inDb) {
      newFiles++;
      console.log(
        `Adding file ${idx} of ${filesToAdd.length}: ${fileName} ...`
      );
      addFile(fileName, () => {
        addFromArr(idx + 1, done);
      });
    } else {
      setImmediate(() => addFromArr(idx + 1, done));
    }
  } else {
    done();
  }
}

console.log("Scan music dir...");
const started = new Date().getTime();
scan("music");
const ended = new Date().getTime();
const seconds = ((ended - started) / 1000).toFixed(3);
console.log(`Scanned ${files} files in ${dirs} dirs in ${seconds} seconds.`);

// Mark files in db
let filesInDb = 0;
let newFiles = 0;
let staleFiles = 0;

const filesToRemove = [];
console.log("Check existing...");
const namesOnly = filesToAdd.map((e) => e.fileName);
db.each(
  "SELECT file FROM track",
  [],
  (err, row) => {
    const idx = namesOnly.indexOf(row.file);
    if (idx !== -1) {
      filesToAdd[idx].inDb = true;
      filesInDb++;
    } else {
      staleFiles++;
      console.log(`File ${row.file} no longer exists.`);
      filesToRemove.push(row.file);
    }
  },
  () => {
    console.log("Adding new files...");
    addFromArr(0, () => {
      if (filesToRemove.length) {
        console.log("Removing old files...");
        db.run(
          "DELETE FROM track WHERE file IN (" +
            filesToRemove.map((e) => "?").join(",") +
            ")",
          filesToRemove,
          (err) => {
            if (err) {
              console.log(err);
            }
            allDone();
          }
        );
      } else {
        allDone();
      }
    });
  }
);

function allDone() {
  console.log(
    `New files: ${newFiles} Existing files: ${filesInDb} Delted files: ${staleFiles}`
  );
  db.close();
  console.log("Db closed, done.");
}