navidrome/model/metadata/map_mediafile.go

package metadata

import (
	"cmp"
	"context"
	"encoding/json"
	"maps"
	"math"
	"slices"
	"strconv"
	"strings"

	"github.com/navidrome/navidrome/log"
	"github.com/navidrome/navidrome/model"
	"github.com/navidrome/navidrome/utils/str"
)

func (md Metadata) ToMediaFile(lib model.Library, folderID string) model.MediaFile {
	mf := model.MediaFile{
		LibraryID: lib.ID,
		FolderID:  folderID,
		Tags:      maps.Clone(md.tags),
	}

	// Title and Album
	mf.Title = md.mapTrackTitle()
	mf.Album = md.mapAlbumName()
	mf.SortTitle = md.String(model.TagTitleSort)
	mf.SortAlbumName = md.String(model.TagAlbumSort)
	mf.OrderTitle = str.SanitizeFieldForSorting(mf.Title)
	mf.OrderAlbumName = str.SanitizeFieldForSortingNoArticle(mf.Album)
	mf.Compilation = md.Bool(model.TagCompilation)

	// Disc and Track info
	mf.TrackNumber, _ = md.NumAndTotal(model.TagTrackNumber)
	mf.DiscNumber, _ = md.NumAndTotal(model.TagDiscNumber)
	mf.DiscSubtitle = md.String(model.TagDiscSubtitle)
	mf.CatalogNum = md.String(model.TagCatalogNumber)
	mf.Comment = md.String(model.TagComment)
	if f := md.NullableFloat(model.TagBPM); f != nil {
		if r := math.Round(*f); r > 0 && r <= math.MaxInt32 {
			mf.BPM = new(int(r))
		}
	}
	mf.Lyrics = md.mapLyrics()
	mf.ExplicitStatus = md.mapExplicitStatusTag()
	md.mapMovementNumbers(mf.Tags)

	// Dates
	date, origDate, relDate := md.mapDates()
	mf.OriginalYear, mf.OriginalDate = origDate.Year(), string(origDate)
	mf.ReleaseYear, mf.ReleaseDate = relDate.Year(), string(relDate)
	mf.Year, mf.Date = date.Year(), string(date)

	// MBIDs
	mf.MbzRecordingID = md.String(model.TagMusicBrainzRecordingID)
	mf.MbzReleaseTrackID = md.String(model.TagMusicBrainzTrackID)
	mf.MbzAlbumID = md.String(model.TagMusicBrainzAlbumID)
	mf.MbzReleaseGroupID = md.String(model.TagMusicBrainzReleaseGroupID)
	mf.MbzAlbumType = md.String(model.TagReleaseType)

	// ReplayGain
	mf.RGAlbumPeak = md.NullableFloat(model.TagReplayGainAlbumPeak)
	mf.RGAlbumGain = md.mapGain(model.TagReplayGainAlbumGain, model.TagR128AlbumGain)
	mf.RGTrackPeak = md.NullableFloat(model.TagReplayGainTrackPeak)
	mf.RGTrackGain = md.mapGain(model.TagReplayGainTrackGain, model.TagR128TrackGain)

	// General properties
	mf.HasCoverArt = md.HasPicture()
	mf.Duration = md.Length()
	mf.BitRate = md.AudioProperties().BitRate
	mf.SampleRate = md.AudioProperties().SampleRate
	if bd := md.AudioProperties().BitDepth; bd > 0 {
		mf.BitDepth = new(bd)
	}
	mf.Channels = md.AudioProperties().Channels
	mf.Codec = md.AudioProperties().Codec
	mf.Path = md.FilePath()
	mf.Suffix = md.Suffix()
	mf.Size = md.Size()
	mf.BirthTime = md.BirthTime()
	mf.UpdatedAt = md.ModTime()

	mf.Participants = md.mapParticipants()
	mf.Artist = md.mapDisplayArtist()
	mf.AlbumArtist = md.mapDisplayAlbumArtist(mf)

	// Persistent IDs
	pid := lib.EffectivePID()
	mf.PID = md.trackPID(mf, pid)
	mf.AlbumID = md.albumID(mf, pid.Album)

	// BFR These IDs will go away once the UI handle multiple participants.
	// BFR For Legacy Subsonic compatibility, we will set them in the API handlers
	mf.ArtistID = mf.Participants.First(model.RoleArtist).ID
	mf.AlbumArtistID = mf.Participants.First(model.RoleAlbumArtist).ID

	// BFR What to do with sort/order artist names?
	mf.OrderArtistName = mf.Participants.First(model.RoleArtist).OrderArtistName
	mf.OrderAlbumArtistName = mf.Participants.First(model.RoleAlbumArtist).OrderArtistName
	mf.SortArtistName = mf.Participants.First(model.RoleArtist).SortArtistName
	mf.SortAlbumArtistName = mf.Participants.First(model.RoleAlbumArtist).SortArtistName

	// Don't store tags that are first-class fields (and are not album-level tags) in the
	// MediaFile struct. This is to avoid redundancy in the DB
	//
	// Remove all tags from the main section that are not flagged as album tags
	for tag, conf := range model.TagMainMappings() {
		if !conf.Album {
			delete(mf.Tags, tag)
		}
	}

	return mf
}

func (md Metadata) AlbumID(mf model.MediaFile, pidConf string) string {
	return md.albumID(mf, pidConf)
}

func (md Metadata) mapGain(rg, r128 model.TagName) *float64 {
	v := md.Gain(rg)
	if v != nil {
		return v
	}
	r128value := md.String(r128)
	if r128value != "" {
		var v, err = strconv.Atoi(r128value)
		if err != nil {
			return nil
		}
		// Convert Q7.8 to float
		value := float64(v) / 256.0
		// Adding 5 dB to normalize with ReplayGain level
		value += 5
		return &value
	}
	return nil
}

// mapMovementNumbers splits ID3 MVIN "n/N" values, like tuple() does for track and disc numbers.
// Totals are only filled when every value has one, so the parallel movement tags stay aligned.
func (md Metadata) mapMovementNumbers(tags model.Tags) {
	values := md.Strings(model.TagMovementNumber)
	if !slices.ContainsFunc(values, func(v string) bool { return strings.Contains(v, "/") }) {
		return
	}
	numbers := make([]string, len(values))
	totals := make([]string, len(values))
	allHaveTotals := true
	for i, v := range values {
		var found bool
		numbers[i], totals[i], found = strings.Cut(v, "/")
		allHaveTotals = allHaveTotals && found
	}
	tags[model.TagMovementNumber] = numbers
	if allHaveTotals && len(md.Strings(model.TagMovementTotal)) == 0 {
		tags[model.TagMovementTotal] = totals
	}
}

func (md Metadata) mapLyrics() string {
	rawLyrics := md.Pairs(model.TagLyrics)

	lyricList := make(model.LyricList, 0, len(rawLyrics))

	ctx := log.NewContext(context.Background(), "file", md.filePath)
	for _, raw := range rawLyrics {
		lang := raw.Key()
		text := raw.Value()

		lyrics, err := model.ParseLyrics(ctx, "", lang, []byte(text))
		if err != nil {
			log.Warn(ctx, "Unexpected failure occurred when parsing lyrics", err)
			continue
		}
		for _, lyric := range lyrics {
			if !lyric.IsEmpty() {
				lyricList = append(lyricList, lyric)
			}
		}
	}

	res, err := json.Marshal(lyricList)
	if err != nil {
		log.Warn("Unexpected error occurred when serializing lyrics", "file", md.filePath, err)
		return ""
	}
	return string(res)
}

func (md Metadata) mapExplicitStatusTag() string {
	switch md.first(model.TagExplicitStatus) {
	case "1", "4":
		return "e"
	case "2":
		return "c"
	default:
		return ""
	}
}

func (md Metadata) mapDates() (date Date, originalDate Date, releaseDate Date) {
	// Start with defaults
	date = md.Date(model.TagRecordingDate)
	originalDate = md.Date(model.TagOriginalDate)
	releaseDate = md.Date(model.TagReleaseDate)

	// For some historic reason, taggers have been writing the Release Date of an album to the Date tag,
	// and leave the Release Date tag empty.
	legacyMappings := (originalDate != "") &&
		(releaseDate == "") &&
		(date >= originalDate)
	if legacyMappings {
		return originalDate, originalDate, date
	}
	// when there's no Date, first fall back to Original Date, then to Release Date.
	date = cmp.Or(date, originalDate, releaseDate)
	return date, originalDate, releaseDate
}