// ── The logic half ────────────────────────────────────────────────────────
//
// Shapes what the database returned into what a client should see. It is a
// separate file from the SQL so that it is testable without a database, and the
// suite next door tests it that way.
//
// The one decision worth pointing at: **a module answers when the game is
// unreachable rather than failing.** The website is the internet-facing process
// and your game is not; the game being down, or the sidecar being mid-restart,
// is an ordinary Tuesday and not an error condition for the site. A page that
// renders "offline, last seen 20 minutes ago" is right; a page that 500s because
// a socket is closed is a module that has made the site's availability depend on
// the game's.

const db = require('./worldStatus.db')

// Past this, the last thing the game said stops being news and starts being
// history. Presentation, so the number lives with the code that shapes the
// response rather than in the client.
const STALE_AFTER_MS = 5 * 60 * 1000

/**
 * The public view of the world's status.
 *
 * Never throws for an absent or stale row: both are answers, not failures.
 */
async function getPublicStatus(now = Date.now()) {
  const row = await db.getStatus()
  if (!row) {
    // No row at all means the schema fragment has not been replayed — a fresh
    // install whose first boot has not finished. Report it as offline rather
    // than as an error; the next boot fixes it.
    return { online: false, players: 0, worldName: null, updatedAt: null, stale: true }
  }

  const updatedAt = row.updatedAt ? new Date(row.updatedAt) : null
  const stale = !updatedAt || now - updatedAt.getTime() > STALE_AFTER_MS

  return {
    // A stale row cannot claim the world is up. The row says what was true when
    // it was written, and nothing has written it since.
    online: Boolean(row.online) && !stale,
    players: stale ? 0 : Number(row.players) || 0,
    worldName: row.worldName || null,
    updatedAt: updatedAt ? updatedAt.toISOString() : null,
    stale,
  }
}

module.exports = { getPublicStatus, STALE_AFTER_MS }