import { pool } from '../pool.js';

const COLS = 'id, name, category, host, url, icon, check_cfg, source, enabled';

// Map a DB row to the service shape the registry/checker expect (check_cfg -> check).
function toSvc(r) {
  return {
    id: r.id, name: r.name, category: r.category, host: r.host, url: r.url,
    icon: r.icon, check: r.check_cfg || {}, source: r.source, enabled: r.enabled
  };
}

export async function listEnabled() {
  const { rows } = await pool.query(
    `SELECT ${COLS} FROM monitored_services WHERE enabled ORDER BY category, name`);
  return rows.map(toSvc);
}

export async function all() {
  const { rows } = await pool.query(
    `SELECT ${COLS} FROM monitored_services ORDER BY category, name`);
  return rows.map(toSvc);
}

// Discovered, not-yet-promoted candidates awaiting the owner's review.
export async function listDiscovered() {
  const { rows } = await pool.query(
    `SELECT ${COLS} FROM monitored_services WHERE source='discovered' AND NOT enabled ORDER BY name`);
  return rows.map(toSvc);
}

export async function get(id) {
  const { rows: [r] } = await pool.query(
    `SELECT ${COLS} FROM monitored_services WHERE id=$1`, [id]);
  return r ? toSvc(r) : null;
}

export async function count() {
  const { rows: [r] } = await pool.query(`SELECT count(*)::int AS n FROM monitored_services`);
  return r.n;
}

export async function create(svc) {
  const { id, name, category = 'other', host = null, url, icon = null,
          check = {}, source = 'manual', enabled = true } = svc;
  const { rows: [r] } = await pool.query(
    `INSERT INTO monitored_services (id, name, category, host, url, icon, check_cfg, source, enabled)
     VALUES ($1,$2,$3,$4,$5,$6,$7::jsonb,$8,$9) RETURNING ${COLS}`,
    [id, name, category, host, url, icon, JSON.stringify(check), source, enabled]);
  return toSvc(r);
}

const PATCHABLE = ['name', 'category', 'host', 'url', 'icon', 'enabled'];
export async function update(id, patch) {
  const sets = [], vals = [];
  for (const k of PATCHABLE) {
    if (patch[k] !== undefined) { vals.push(patch[k]); sets.push(`${k}=$${vals.length}`); }
  }
  if (patch.check !== undefined) { vals.push(JSON.stringify(patch.check)); sets.push(`check_cfg=$${vals.length}::jsonb`); }
  if (!sets.length) return get(id);
  vals.push(id);
  const { rows: [r] } = await pool.query(
    `UPDATE monitored_services SET ${sets.join(', ')}, updated_at=now() WHERE id=$${vals.length} RETURNING ${COLS}`,
    vals);
  return r ? toSvc(r) : null;
}

export async function remove(id) {
  const { rowCount } = await pool.query(`DELETE FROM monitored_services WHERE id=$1`, [id]);
  return rowCount > 0;
}

// Insert a discovered candidate (disabled, source='discovered') unless a service
// with the same id OR url already exists — never clobbers a curated entry.
export async function upsertDiscovered(svc) {
  const { id, name, category = 'other', host = null, url, icon = null, check = {} } = svc;
  const { rows: [r] } = await pool.query(
    `INSERT INTO monitored_services (id, name, category, host, url, icon, check_cfg, source, enabled)
     SELECT $1,$2,$3,$4,$5,$6,$7::jsonb,'discovered',false
     WHERE NOT EXISTS (SELECT 1 FROM monitored_services WHERE url=$5)
     ON CONFLICT (id) DO NOTHING
     RETURNING ${COLS}`,
    [id, name, category, host, url, icon, JSON.stringify(check)]);
  return r ? toSvc(r) : null;   // null = already existed (skipped)
}