package subsonic

import (
	"git.noroutes.net/NoRoutes/vibetunes/internal/database"
)

func init() {
	registerExtension("songLyrics", 1, 2)
	register("getLyricsBySongId", handleGetLyricsBySongID)
}

// handleGetLyricsBySongID implements the songLyrics extension. It never
// fakes cue-level timing: cueLine data is only emitted for entries that
// were actually parsed from an Enhanced-LRC-style source with word/
// syllable cues, and only when the client asked for enhanced=true.
func handleGetLyricsBySongID(rc *Context) *apiError {
	id, aerr := rc.Params.Required("id")
	if aerr != nil {
		return aerr
	}
	enhanced := rc.Params.Bool("enhanced", false)

	db := rc.Server.DB
	if _, err := database.GetSong(db, id); err != nil {
		return errNotFound("Song")
	}

	rows, err := database.GetSongStructuredLyrics(db, id)
	if err != nil {
		return newError(ErrGeneric, err.Error())
	}

	list := &LyricsList{}
	for _, row := range rows {
		kind := "main" // every entry VibeSonic currently stores/ingests is a primary lyric layer, never a translation or pronunciation.
		if !enhanced && kind != "main" {
			continue
		}

		sl := StructuredLyrics{
			Lang:   row.Language,
			Synced: row.Synced,
			Line:   make([]Line, 0, len(row.Lines)),
		}
		if enhanced {
			sl.Kind = kind
		}

		hasCues := false
		for _, l := range row.Lines {
			line := Line{Value: l.Text}
			if row.Synced && l.StartMs != nil {
				start := *l.StartMs
				line.Start = &start
			}
			sl.Line = append(sl.Line, line)
			if len(l.Words) > 0 {
				hasCues = true
			}
		}

		if enhanced && row.Synced && hasCues {
			sl.CueLine = make([]CueLine, 0, len(row.Lines))
			for i, l := range row.Lines {
				if len(l.Words) == 0 {
					continue
				}
				cl := CueLine{Index: i, Value: l.Text}
				if l.StartMs != nil {
					cl.Start = *l.StartMs
				}
				cl.Cue = make([]Cue, 0, len(l.Words))
				for _, w := range l.Words {
					cue := Cue{Start: w.StartMs, ByteStart: w.ByteStart, ByteEnd: w.ByteEnd, Value: w.Text}
					if w.EndMs != nil {
						end := *w.EndMs
						cue.End = &end
					}
					cl.Cue = append(cl.Cue, cue)
				}
				if last := l.Words[len(l.Words)-1]; last.EndMs != nil {
					cl.End = *last.EndMs
				}
				sl.CueLine = append(sl.CueLine, cl)
			}
		}

		list.StructuredLyrics = append(list.StructuredLyrics, sl)
	}

	rc.Response = newResponse()
	rc.Response.LyricsList = list
	return nil
}