-- v4.1 — Global Invoice (Factura Global Mensual)
-- Supports grouping cash sales (<= $2,000) into a single monthly CFDI.

-- Link global invoices to their constituent sales
CREATE TABLE IF NOT EXISTS global_invoice_sales (
    global_invoice_id INTEGER NOT NULL REFERENCES cfdi_queue(id) ON DELETE CASCADE,
    sale_id           INTEGER NOT NULL REFERENCES sales(id) ON DELETE CASCADE,
    PRIMARY KEY (global_invoice_id, sale_id)
);

CREATE INDEX IF NOT EXISTS idx_gis_global ON global_invoice_sales(global_invoice_id);
CREATE INDEX IF NOT EXISTS idx_gis_sale   ON global_invoice_sales(sale_id);

-- Track which sales have been included in any global invoice
-- (quick lookup without joining global_invoice_sales)
ALTER TABLE sales ADD COLUMN IF NOT EXISTS global_invoiced_at TIMESTAMPTZ;
CREATE INDEX IF NOT EXISTS idx_sales_global_invoiced_at ON sales(global_invoiced_at) WHERE global_invoiced_at IS NULL;