feat: the admin Overview shows who is listening, downloads, the library and its disk, and the server's version, uptime and recent errors; a download waiting on you, a client not answering or a full disk count in its verdict (M504 #5627 #5628 #5629 #5630)

The version moves to internal/buildinfo, so /rest/ping reports the build
instead of "dev".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/db/dbq/admin_status.sql.go

@@ -0,0 +1,168 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.31.1
+// source: admin_status.sql
+
+package dbq
+
+import (
+	"context"
+
+	"github.com/jackc/pgx/v5/pgtype"
+)
+
+const downloadsStatus = `-- name: DownloadsStatus :one
+SELECT COUNT(*) FILTER (WHERE ended_at IS NULL AND import_state IN ('', 'downloading', 'waiting', 'importing'))::bigint AS running,
+       COUNT(*) FILTER (WHERE ended_at IS NULL AND import_state IN ('review', 'failed'))::bigint AS needs_you,
+       MIN(COALESCE(import_updated_at, grabbed_at)) FILTER (WHERE ended_at IS NULL AND import_state IN ('review', 'failed'))::timestamptz AS needs_you_since,
+       COUNT(*) FILTER (WHERE imported_at > now() - INTERVAL '24 hours')::bigint AS imported_day,
+       COUNT(*) FILTER (WHERE ended_at > now() - INTERVAL '24 hours'
+                          AND end_reason IN ('stalled', 'failed', 'gone', 'abandoned'))::bigint AS given_up_day
+  FROM grabs
+ WHERE ended_at IS NULL
+    OR ended_at > now() - INTERVAL '24 hours'
+    OR imported_at > now() - INTERVAL '24 hours'
+`
+
+type DownloadsStatusRow struct {
+	Running       int64
+	NeedsYou      int64
+	NeedsYouSince pgtype.Timestamptz
+	ImportedDay   int64
+	GivenUpDay    int64
+}
+
+// Downloads at a glance: running, waiting on a person (and since when), and
+// the last day's imports and give-ups.
+func (q *Queries) DownloadsStatus(ctx context.Context) (DownloadsStatusRow, error) {
+	row := q.db.QueryRow(ctx, downloadsStatus)
+	var i DownloadsStatusRow
+	err := row.Scan(
+		&i.Running,
+		&i.NeedsYou,
+		&i.NeedsYouSince,
+		&i.ImportedDay,
+		&i.GivenUpDay,
+	)
+	return i, err
+}
+
+const libraryStatus = `-- name: LibraryStatus :one
+SELECT COUNT(*)::bigint                   AS tracks,
+       COUNT(DISTINCT album_id)::bigint   AS albums,
+       COUNT(DISTINCT artist_id)::bigint  AS artists,
+       COALESCE(SUM(file_size), 0)::bigint AS bytes
+  FROM tracks
+ WHERE missing_since IS NULL
+`
+
+type LibraryStatusRow struct {
+	Tracks  int64
+	Albums  int64
+	Artists int64
+	Bytes   int64
+}
+
+// What the library holds on disk: tracks whose files are present, the
+// albums and artists they make, and their size.
+func (q *Queries) LibraryStatus(ctx context.Context) (LibraryStatusRow, error) {
+	row := q.db.QueryRow(ctx, libraryStatus)
+	var i LibraryStatusRow
+	err := row.Scan(
+		&i.Tracks,
+		&i.Albums,
+		&i.Artists,
+		&i.Bytes,
+	)
+	return i, err
+}
+
+const listListeningNow = `-- name: ListListeningNow :many
+
+SELECT pe.started_at, pe.client_id, pe.device_class,
+       u.username,
+       t.id AS track_id, t.title AS track_title, t.duration_ms,
+       ar.name AS artist_name,
+       al.id AS album_id, al.title AS album_title
+  FROM play_events pe
+  JOIN users u    ON u.id = pe.user_id
+  JOIN tracks t   ON t.id = pe.track_id
+  JOIN albums al  ON al.id = t.album_id
+  JOIN artists ar ON ar.id = t.artist_id
+ WHERE pe.ended_at IS NULL
+   AND pe.started_at > now() - INTERVAL '24 hours'
+   AND pe.started_at + make_interval(secs => t.duration_ms / 1000.0) + INTERVAL '5 minutes' > now()
+ ORDER BY pe.started_at DESC
+ LIMIT 20
+`
+
+type ListListeningNowRow struct {
+	StartedAt   pgtype.Timestamptz
+	ClientID    *string
+	DeviceClass *string
+	Username    string
+	TrackID     pgtype.UUID
+	TrackTitle  string
+	DurationMs  int32
+	ArtistName  string
+	AlbumID     pgtype.UUID
+	AlbumTitle  string
+}
+
+// The admin Overview's status sections (M504): who is listening, what is
+// downloading, what the library holds. Each is one cheap read.
+// Plays in progress: open play events still inside their track's length,
+// with a few minutes' grace for a pause. A client that never says a play
+// ended would otherwise read as listening until the 24-hour sweep closes it.
+func (q *Queries) ListListeningNow(ctx context.Context) ([]ListListeningNowRow, error) {
+	rows, err := q.db.Query(ctx, listListeningNow)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var items []ListListeningNowRow
+	for rows.Next() {
+		var i ListListeningNowRow
+		if err := rows.Scan(
+			&i.StartedAt,
+			&i.ClientID,
+			&i.DeviceClass,
+			&i.Username,
+			&i.TrackID,
+			&i.TrackTitle,
+			&i.DurationMs,
+			&i.ArtistName,
+			&i.AlbumID,
+			&i.AlbumTitle,
+		); err != nil {
+			return nil, err
+		}
+		items = append(items, i)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return items, nil
+}
+
+const playsLastDay = `-- name: PlaysLastDay :one
+SELECT COUNT(*)::bigint                AS plays,
+       COUNT(DISTINCT user_id)::bigint AS listeners,
+       MAX(started_at)::timestamptz    AS last_at
+  FROM play_events
+ WHERE started_at > now() - INTERVAL '24 hours'
+`
+
+type PlaysLastDayRow struct {
+	Plays     int64
+	Listeners int64
+	LastAt    pgtype.Timestamptz
+}
+
+// The last day's listening, for the line under Listening now.
+func (q *Queries) PlaysLastDay(ctx context.Context) (PlaysLastDayRow, error) {
+	row := q.db.QueryRow(ctx, playsLastDay)
+	var i PlaysLastDayRow
+	err := row.Scan(&i.Plays, &i.Listeners, &i.LastAt)
+	return i, err
+}