-- Completa los nombres de los snapshots fiscales de proforma_items.
--
-- Fuente: tax_definitions vigente (misma company_id y code).
-- Seguridad:
--   * Solo completa iva_name, rec_name y retention_name vacíos o NULL.
--   * No modifica códigos, porcentajes, escalas ni importes.
--   * No inventa nombres: los códigos sin TaxDefinition no se actualizan.
--
-- Ejecutar primero los SELECT de diagnóstico. Ejecutar el UPDATE dentro de una
-- transacción únicamente después de revisar los resultados.

-- Diagnóstico: filas que el backfill completará.
SELECT
  pi.item_id,
  pi.proforma_id,
  p.company_id,
  pi.iva_code,
  iva.name AS iva_name_source,
  pi.rec_code,
  rec.name AS rec_name_source,
  pi.retention_code,
  retention.name AS retention_name_source
FROM proforma_items pi
INNER JOIN proformas p ON p.id = pi.proforma_id
LEFT JOIN tax_definitions iva
  ON iva.company_id = p.company_id
  AND iva.code = pi.iva_code
  AND iva.deleted_at IS NULL
LEFT JOIN tax_definitions rec
  ON rec.company_id = p.company_id
  AND rec.code = pi.rec_code
  AND rec.deleted_at IS NULL
LEFT JOIN tax_definitions retention
  ON retention.company_id = p.company_id
  AND retention.code = pi.retention_code
  AND retention.deleted_at IS NULL
WHERE (NULLIF(TRIM(pi.iva_name), '') IS NULL AND NULLIF(TRIM(pi.iva_code), '') IS NOT NULL AND iva.id IS NOT NULL)
   OR (NULLIF(TRIM(pi.rec_name), '') IS NULL AND NULLIF(TRIM(pi.rec_code), '') IS NOT NULL AND rec.id IS NOT NULL)
   OR (
     NULLIF(TRIM(pi.retention_name), '') IS NULL
     AND NULLIF(TRIM(pi.retention_code), '') IS NOT NULL
     AND retention.id IS NOT NULL
   );

-- Diagnóstico: códigos con nombre vacío que no tienen una TaxDefinition disponible.
-- Estas filas se preservan sin cambios y requieren una decisión de recuperación manual.
SELECT
  pi.item_id,
  pi.proforma_id,
  p.company_id,
  CASE
    WHEN NULLIF(TRIM(pi.iva_name), '') IS NULL AND NULLIF(TRIM(pi.iva_code), '') IS NOT NULL AND iva.id IS NULL
      THEN pi.iva_code
  END AS missing_iva_definition_code,
  CASE
    WHEN NULLIF(TRIM(pi.rec_name), '') IS NULL AND NULLIF(TRIM(pi.rec_code), '') IS NOT NULL AND rec.id IS NULL
      THEN pi.rec_code
  END AS missing_rec_definition_code,
  CASE
    WHEN NULLIF(TRIM(pi.retention_name), '') IS NULL AND NULLIF(TRIM(pi.retention_code), '') IS NOT NULL AND retention.id IS NULL
      THEN pi.retention_code
  END AS missing_retention_definition_code
FROM proforma_items pi
INNER JOIN proformas p ON p.id = pi.proforma_id
LEFT JOIN tax_definitions iva
  ON iva.company_id = p.company_id
  AND iva.code = pi.iva_code
  AND iva.deleted_at IS NULL
LEFT JOIN tax_definitions rec
  ON rec.company_id = p.company_id
  AND rec.code = pi.rec_code
  AND rec.deleted_at IS NULL
LEFT JOIN tax_definitions retention
  ON retention.company_id = p.company_id
  AND retention.code = pi.retention_code
  AND retention.deleted_at IS NULL
WHERE (NULLIF(TRIM(pi.iva_name), '') IS NULL AND NULLIF(TRIM(pi.iva_code), '') IS NOT NULL AND iva.id IS NULL)
   OR (NULLIF(TRIM(pi.rec_name), '') IS NULL AND NULLIF(TRIM(pi.rec_code), '') IS NOT NULL AND rec.id IS NULL)
   OR (
     NULLIF(TRIM(pi.retention_name), '') IS NULL
     AND NULLIF(TRIM(pi.retention_code), '') IS NOT NULL
     AND retention.id IS NULL
   );

START TRANSACTION;

UPDATE proforma_items pi
INNER JOIN proformas p ON p.id = pi.proforma_id
LEFT JOIN tax_definitions iva
  ON iva.company_id = p.company_id
  AND iva.code = pi.iva_code
  AND iva.deleted_at IS NULL
LEFT JOIN tax_definitions rec
  ON rec.company_id = p.company_id
  AND rec.code = pi.rec_code
  AND rec.deleted_at IS NULL
LEFT JOIN tax_definitions retention
  ON retention.company_id = p.company_id
  AND retention.code = pi.retention_code
  AND retention.deleted_at IS NULL
SET
  pi.iva_name = CASE
    WHEN NULLIF(TRIM(pi.iva_name), '') IS NULL AND NULLIF(TRIM(pi.iva_code), '') IS NOT NULL AND iva.id IS NOT NULL
      THEN iva.name
    ELSE pi.iva_name
  END,
  pi.rec_name = CASE
    WHEN NULLIF(TRIM(pi.rec_name), '') IS NULL AND NULLIF(TRIM(pi.rec_code), '') IS NOT NULL AND rec.id IS NOT NULL
      THEN rec.name
    ELSE pi.rec_name
  END,
  pi.retention_name = CASE
    WHEN NULLIF(TRIM(pi.retention_name), '') IS NULL AND NULLIF(TRIM(pi.retention_code), '') IS NOT NULL AND retention.id IS NOT NULL
      THEN retention.name
    ELSE pi.retention_name
  END
WHERE (NULLIF(TRIM(pi.iva_name), '') IS NULL AND NULLIF(TRIM(pi.iva_code), '') IS NOT NULL AND iva.id IS NOT NULL)
   OR (NULLIF(TRIM(pi.rec_name), '') IS NULL AND NULLIF(TRIM(pi.rec_code), '') IS NOT NULL AND rec.id IS NOT NULL)
   OR (
     NULLIF(TRIM(pi.retention_name), '') IS NULL
     AND NULLIF(TRIM(pi.retention_code), '') IS NOT NULL
     AND retention.id IS NOT NULL
   );

-- Revisar ROW_COUNT() y los dos diagnósticos anteriores antes de confirmar.
-- COMMIT;
-- ROLLBACK;