// helpers/normalizeActivity.js

function safeJsonParse(value, fallback) {
  try {
    return value ? JSON.parse(value) : fallback;
  } catch {
    return fallback;
  }
}

function normalizeActivity(a) {
  // ============================
  // GPS compatibile con /photos
  // ============================
  const gps = (a.center_latitude != null && a.center_longitude != null)
    ? {
        lat: a.center_latitude,
        lng: a.center_longitude,
        alt: a.min_elevation_meters ?? null
      }
    : null;

  // ============================
  // JSON fields
  // ============================
  const location = safeJsonParse(a.location, null);
  const tags = safeJsonParse(a.tags, []);
  const diagnostics = safeJsonParse(a.diagnostics, null);

  // Preview percorso per thumbnails attività
  const track_preview = safeJsonParse(a.track_preview, []);

  // ============================
  // Path stile /photos
  // ============================
  const path = `/activities/${a.user}/original/${a.cartella}/${a.file_name}`;

  // ============================
  // MIME type
  // ============================
  const mime_type = a.format || "application/octet-stream";

  // ============================
  // mtimeMs compatibile progressiveSync
  // ============================
  const mtimeMs =
    a.last_modified_millis ??
    a.date_modified_millis ??
    a.date_added_millis ??
    Date.now();

  return {
    // ============================
    // Campi base come /photos
    // ============================
    id: a.id,
    user: a.user,
    cartella: a.cartella,
    name: a.file_name,
    path,
    mime_type,
    size_bytes: a.size_bytes,
    mtimeMs,

    taken_at: a.start_time_millis
      ? new Date(Number(a.start_time_millis)).toISOString()
      : null,

    data: a.start_time_millis
      ? new Date(Number(a.start_time_millis)).toISOString()
      : null,

    location,
    gps,

    // ============================
    // Campi speciali delle activity
    // ============================
    file_name: a.file_name,
    file_extension: a.file_extension,
    format: a.format,
    display_name: a.display_name,
    route_name: a.route_name,
    title: a.title,
    description: a.description,
    notes: a.notes,
    sport: a.sport,
    activity_type: a.activity_type,
    device_manufacturer: a.device_manufacturer,
    device_model: a.device_model,
    source_app: a.source_app,

    start_time_millis: a.start_time_millis,
    end_time_millis: a.end_time_millis,
    duration_millis: a.duration_millis,

    distance_meters: a.distance_meters,
    elevation_gain_meters: a.elevation_gain_meters,
    elevation_loss_meters: a.elevation_loss_meters,

    min_elevation_meters: a.min_elevation_meters,
    max_elevation_meters: a.max_elevation_meters,

    file_distance_meters: a.file_distance_meters,
    file_elevation_gain_meters: a.file_elevation_gain_meters,

    computed_distance_meters: a.computed_distance_meters,
    computed_elevation_gain_meters: a.computed_elevation_gain_meters,

    average_speed_mps: a.average_speed_mps,
    max_speed_mps: a.max_speed_mps,
    average_pace_sec_per_km: a.average_pace_sec_per_km,

    average_heart_rate: a.average_heart_rate,
    max_heart_rate: a.max_heart_rate,
    average_cadence: a.average_cadence,
    max_cadence: a.max_cadence,

    calories: a.calories,
    power_avg: a.power_avg,
    power_max: a.power_max,

    point_count: a.point_count,
    segment_count: a.segment_count,
    lap_count: a.lap_count,

    min_latitude: a.min_latitude,
    max_latitude: a.max_latitude,
    min_longitude: a.min_longitude,
    max_longitude: a.max_longitude,
    center_latitude: a.center_latitude,
    center_longitude: a.center_longitude,

    last_modified_millis: a.last_modified_millis,
    date_added_millis: a.date_added_millis,
    date_modified_millis: a.date_modified_millis,
    last_scan_millis: a.last_scan_millis,

    is_favorite: !!a.is_favorite,
    is_hidden: !!a.is_hidden,
    rating: a.rating,

    tags,

    // Preview percorso per thumbnails FIT/GPX/TCX
    track_preview,

    scan_status: a.scan_status,
    scan_error: a.scan_error,

    // Importante per soft delete in gallery
    deleted_at: a.deleted_at || null,

    diagnostics
  };
}

module.exports = normalizeActivity;