package web

import (
	"encoding/json"
	"net/http"

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

type lyricsLineJSON struct {
	Text    string `json:"text"`
	StartMs *int   `json:"startMs,omitempty"`
}

type lyricsResponseJSON struct {
	Synced bool             `json:"synced"`
	Lines  []lyricsLineJSON `json:"lines"`
}

// handleLyrics serves the web player's lyrics panel: the best available
// stored structuredLyrics entry for a song, as line text plus a start
// time when the source actually has one. Prefers a synced entry over
// an unsynced one so the panel can highlight/click-to-seek whenever
// that data exists, but never fabricates timing for an unsynced entry.
func (h *Web) handleLyrics(w http.ResponseWriter, r *http.Request) {
	songID := r.PathValue("id")
	entries, err := database.GetSongStructuredLyrics(h.DB, songID)
	if err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}

	var best *database.StructuredLyricsRow
	for i := range entries {
		if best == nil || (entries[i].Synced && !best.Synced) {
			best = &entries[i]
		}
	}

	out := lyricsResponseJSON{Lines: []lyricsLineJSON{}}
	if best != nil {
		out.Synced = best.Synced
		for _, l := range best.Lines {
			out.Lines = append(out.Lines, lyricsLineJSON{Text: l.Text, StartMs: l.StartMs})
		}
	}

	w.Header().Set("Content-Type", "application/json")
	_ = json.NewEncoder(w).Encode(out)
}