-- Estado: vigente / manual.
-- Objetivo:
--   1. Anadir `issued_invoices.invoice_reference` si no existe.
--   2. Backfill conservador para facturas emitidas existentes.
--   3. Validar que no quedan filas sin snapshot documental.
--   4. Endurecer a NOT NULL cuando la validacion sea correcta.
--
-- No ejecutar automaticamente desde backend.
-- Revisar antes el nombre real de la tabla `document_series` y sus columnas
-- `prefix`, `padding`, `suffix` en el entorno objetivo.

START TRANSACTION;

ALTER TABLE issued_invoices
ADD COLUMN IF NOT EXISTS invoice_reference VARCHAR(64) NULL AFTER invoice_number;

UPDATE issued_invoices ii
JOIN document_series ds
  ON ds.company_id = ii.company_id
 AND ds.code = ii.invoice_series_code
 AND ds.document_type = 'issued_invoice'
SET ii.invoice_reference = CONCAT(
  COALESCE(ds.prefix, ''),
  LPAD(CAST(ii.invoice_number AS CHAR), ds.padding, '0'),
  COALESCE(ds.suffix, '')
)
WHERE ii.invoice_reference IS NULL;

SELECT id, source_proforma_id, invoice_series_code, invoice_number, invoice_reference
FROM issued_invoices
WHERE invoice_reference IS NULL;

SELECT
  ii.id,
  ii.invoice_series_code,
  ii.invoice_number,
  ii.invoice_reference,
  ds.prefix,
  ds.padding,
  ds.suffix
FROM issued_invoices ii
JOIN document_series ds
  ON ds.company_id = ii.company_id
 AND ds.code = ii.invoice_series_code
 AND ds.document_type = 'issued_invoice'
ORDER BY ii.created_at DESC
LIMIT 20;

-- Ejecutar solo cuando la consulta anterior no devuelva filas.
ALTER TABLE issued_invoices
MODIFY COLUMN invoice_reference VARCHAR(64) NOT NULL;

COMMIT;