-- reimbursement_forms: payment voucher fields
ALTER TABLE "reimbursement_forms"
  ADD COLUMN "payment_voucher_no" VARCHAR(50),
  ADD COLUMN "payment_date" DATE,
  ADD COLUMN "payment_channel" VARCHAR(20),
  ADD COLUMN "paid_at" TIMESTAMP(3),
  ADD COLUMN "paid_by" UUID;

ALTER TABLE "reimbursement_forms"
  ADD CONSTRAINT "reimbursement_forms_paid_by_fkey"
  FOREIGN KEY ("paid_by") REFERENCES "employees"("id") ON DELETE SET NULL ON UPDATE CASCADE;

CREATE INDEX "reimbursement_forms_paid_by_idx" ON "reimbursement_forms"("paid_by");

-- invoice_pool: OCR lock fields
ALTER TABLE "invoice_pool"
  ADD COLUMN "ocr_locked_at" TIMESTAMP(3),
  ADD COLUMN "ocr_lock_owner" VARCHAR(128);

CREATE INDEX "idx_invoice_pool_ocr_queue"
ON "invoice_pool"("status", "ocr_locked_at", "created_at");

-- audit_logs: query acceleration
CREATE INDEX "idx_audit_logs_query"
ON "audit_logs"("created_at" DESC, "actor_id", "action");