// SQL for the reserved-name review queue and the §2.9 approval queue.

const { query } = require('../../utils/db')

// ── The hide/display state on `teams` ──────────────────────────────────────

async function setHidden(teamId, { hidden, reason, term }) {
  await query(
    'UPDATE teams SET hidden = ?, hidden_reason = ?, hidden_term = ? WHERE id = ?',
    [hidden ? 1 : 0, hidden ? reason : null, hidden ? term || null : null, teamId],
  )
}

/**
 * Record that a human has decided about this name.
 *
 * What makes a staff decision STICKY (§2.8.3). Re-screening runs on every sync,
 * and without this stamp an operator adding a reserved term — or simply renaming
 * the deployment — would re-hide a Team staff had already allowed, every fifteen
 * minutes, forever.
 */
async function markNameReviewed(teamId) {
  await query('UPDATE teams SET name_reviewed_at = NOW() WHERE id = ?', [teamId])
}

async function setDisplayNameOverride(teamId, displayName) {
  await query('UPDATE teams SET display_name_override = ? WHERE id = ?', [displayName, teamId])
}

/** Active teams whose name has never been screened by a human. */
async function unreviewedActive(moduleId) {
  return query(
    `SELECT id, name, hidden, hidden_reason FROM teams
     WHERE module_id = ? AND status = 'active' AND name_reviewed_at IS NULL`,
    [moduleId],
  )
}

/** The reserved-name review queue (§2.8.3). */
async function reviewQueue() {
  return query(
    `SELECT id, name, slug, hidden_term, display_name_override, member_count, created_at
     FROM teams
     WHERE status = 'active' AND hidden = 1 AND hidden_reason = 'reserved_name' AND name_reviewed_at IS NULL
     ORDER BY created_at DESC`,
  )
}

// ── team_moderation_requests (§2.9) ────────────────────────────────────────

const REQUEST_COLUMNS = `
  id, team_id, action, payload, reason, requested_by, requested_username, requested_at,
  status, decided_by, decided_username, decided_at, decision_note`

async function insertRequest({ teamId, action, payload, reason, requestedBy, requestedUsername }) {
  const res = await query(
    `INSERT INTO team_moderation_requests
       (team_id, action, payload, reason, requested_by, requested_username)
     VALUES (?, ?, ?, ?, ?, ?)`,
    [teamId, action, payload == null ? null : JSON.stringify(payload), reason, requestedBy, requestedUsername],
  )
  return res.insertId
}

async function findRequest(id) {
  const rows = await query(`SELECT ${REQUEST_COLUMNS} FROM team_moderation_requests WHERE id = ?`, [id])
  return rows[0]
}

/** The approval queue. Decided rows are kept — see §2.9 — so `status` is a filter. */
async function listRequests({ status = 'pending', limit = 100 } = {}) {
  const params = []
  let sql = `SELECT r.${REQUEST_COLUMNS.trim().split(/,\s*/).join(', r.')},
                    t.name AS team_name, t.slug AS team_slug
             FROM team_moderation_requests r JOIN teams t ON t.id = r.team_id`
  if (status !== 'all') {
    sql += ' WHERE r.status = ?'
    params.push(status)
  }
  sql += ' ORDER BY r.requested_at DESC, r.id DESC LIMIT ?'
  params.push(limit)
  return query(sql, params)
}

/**
 * Decide a request, but only if it is still pending.
 *
 * The `status = 'pending'` guard is the concurrency control: two admins opening
 * the same queue and both clicking approve would otherwise each apply the action,
 * and the second would overwrite the first's record of who decided it. The caller
 * applies the effect only when this reports a row was actually moved.
 */
async function decideRequest(id, { status, decidedBy, decidedUsername, note }) {
  const res = await query(
    `UPDATE team_moderation_requests
     SET status = ?, decided_by = ?, decided_username = ?, decided_at = NOW(), decision_note = ?
     WHERE id = ? AND status = 'pending'`,
    [status, decidedBy, decidedUsername, note, id],
  )
  return res.affectedRows > 0
}

/** Pending requests for one team — shown on its admin page so a second is not filed. */
async function pendingForTeam(teamId) {
  return query(
    `SELECT ${REQUEST_COLUMNS} FROM team_moderation_requests
     WHERE team_id = ? AND status = 'pending' ORDER BY requested_at`,
    [teamId],
  )
}

module.exports = {
  setHidden,
  markNameReviewed,
  setDisplayNameOverride,
  unreviewedActive,
  reviewQueue,
  insertRequest,
  findRequest,
  listRequests,
  decideRequest,
  pendingForTeam,
}