// Postgres-backed progress store — same shape/semantics as the SQLite loadProgress/saveProgress
// it replaces in backend/server.js, now backed by the `progress` table (migrations/004).

async function loadProgress(pool, studentId) {
  const { rows } = await pool.query('SELECT * FROM progress WHERE student_id = $1', [studentId]);
  return Object.fromEntries(rows.map((r) => [r.scenario_id, {
    status: r.status,
    attempts: r.attempts,
    last_validated: r.last_validated,
    completed_at: r.completed_at,
    started_at: r.started_at,
    notes: r.notes,
    time_spent_seconds: r.time_spent_seconds || 0,
  }]));
}

async function saveOneProgress(pool, studentId, scenarioId, p) {
  await pool.query(
    `INSERT INTO progress (student_id, scenario_id, status, attempts, last_validated, completed_at, started_at, notes, time_spent_seconds)
     VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
     ON CONFLICT (student_id, scenario_id) DO UPDATE SET
       status = excluded.status, attempts = excluded.attempts, last_validated = excluded.last_validated,
       completed_at = excluded.completed_at, started_at = excluded.started_at, notes = excluded.notes,
       time_spent_seconds = excluded.time_spent_seconds`,
    [studentId, scenarioId, p.status || null, p.attempts || 0, p.last_validated || null,
      p.completed_at || null, p.started_at || null, p.notes || null, p.time_spent_seconds || 0]
  );
}

async function touchStudent(pool, studentId) {
  await pool.query(`UPDATE students SET last_active_at = now() WHERE student_id = $1`, [studentId]).catch(() => {});
}

module.exports = { loadProgress, saveOneProgress, touchStudent };