import { pool } from '../pool.js';
import { recordAudit } from './audit_stub.js';
import { triggerEmbed } from '../../jobs/triggers.js';

async function snapshot(client, page_id, body_md, edited_by) {
  await client.query(
    `INSERT INTO page_revisions(page_id, body_md, edited_by)
     VALUES($1,$2,$3)`,
    [page_id, body_md, edited_by || null]
  );
}

export async function create({ space_id, slug, title, body_md = '', parent_id }, actor) {
  const client = await pool.connect();
  try {
    await client.query('BEGIN');
    const { rows: [r] } = await client.query(
      `INSERT INTO pages(space_id, slug, title, body_md, parent_id)
       VALUES($1,$2,$3,$4,$5) RETURNING *`,
      [space_id, slug, title, body_md, parent_id || null]
    );
    await snapshot(client, r.id, body_md, actor?.kind);
    await client.query('COMMIT');
    await recordAudit(actor, 'create', 'page', r.id, null, r);
    await triggerEmbed('page', r.id);
    return r;
  } catch (e) {
    await client.query('ROLLBACK'); throw e;
  } finally {
    client.release();
  }
}

export async function getById(id) {
  const { rows: [r] } = await pool.query(`SELECT * FROM pages WHERE id=$1`, [id]);
  return r;
}

export async function getBySlug(space_id, slug) {
  const { rows: [r] } = await pool.query(
    `SELECT * FROM pages WHERE space_id=$1 AND slug=$2`, [space_id, slug]
  );
  return r;
}

export async function listBySpace(space_id) {
  const { rows } = await pool.query(
    `SELECT id, space_id, slug, title, parent_id, updated_at
     FROM pages WHERE space_id=$1 ORDER BY title`, [space_id]
  );
  return rows;
}

export async function listRevisions(page_id) {
  const { rows } = await pool.query(
    `SELECT * FROM page_revisions WHERE page_id=$1 ORDER BY created_at DESC`,
    [page_id]
  );
  return rows;
}

export async function update(id, patch, actor) {
  const before = await getById(id);
  const client = await pool.connect();
  try {
    await client.query('BEGIN');
    const fields = ['slug','title','body_md','body_html','parent_id','embedding'];
    const sets = [], vals = [];
    let i = 1;
    for (const f of fields) {
      if (patch[f] !== undefined) { sets.push(`${f}=$${i++}`); vals.push(patch[f]); }
    }
    sets.push(`updated_at=now()`);
    vals.push(id);
    const { rows: [r] } = await client.query(
      `UPDATE pages SET ${sets.join(', ')} WHERE id=$${i} RETURNING *`,
      vals
    );
    if (patch.body_md !== undefined && patch.body_md !== before.body_md) {
      await snapshot(client, id, patch.body_md, actor?.kind);
    }
    await client.query('COMMIT');
    await recordAudit(actor, 'update', 'page', id, before, r);
    if (patch.embedding === undefined) await triggerEmbed('page', id);
    return r;
  } catch (e) {
    await client.query('ROLLBACK'); throw e;
  } finally {
    client.release();
  }
}

export async function del(id, actor) {
  const before = await getById(id);
  await pool.query(`DELETE FROM pages WHERE id=$1`, [id]);
  await recordAudit(actor, 'delete', 'page', id, before, null);
}