<?php
include '../db/db.php';
$term = $conn->real_escape_string($_GET['q'] ?? '');
$sql = "
  SELECT id,
    CONCAT(noDocumento,' - ',nombre,' ',apellido,
      IF(razonSocial<>'' AND razonSocial<>nombre, CONCAT(' (',razonSocial,')'), '')
    ) AS text
  FROM tb_terceros
  WHERE noDocumento LIKE '%{$term}%'
     OR nombre LIKE '%{$term}%'
     OR apellido LIKE '%{$term}%'
     OR razonSocial LIKE '%{$term}%'
  ORDER BY nombre
  LIMIT 20";
$res = $conn->query($sql);
$data = ['results' => []];
while ($r = $res->fetch_assoc()) {
    $data['results'][] = ['id' => $r['id'], 'text' => $r['text']];
}
header('Content-Type: application/json');
echo json_encode($data);