-- Inventory table
CREATE TABLE inventory (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    outlet_id UUID NOT NULL REFERENCES outlets(id) ON DELETE CASCADE,
    product_id UUID NOT NULL REFERENCES products(id) ON DELETE CASCADE,
    quantity INTEGER NOT NULL DEFAULT 0 CHECK (quantity >= 0),
    reorder_level INTEGER DEFAULT 0 CHECK (reorder_level >= 0),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    UNIQUE(outlet_id, product_id)
);

-- Indexes
CREATE INDEX idx_inventory_outlet_id ON inventory(outlet_id);
CREATE INDEX idx_inventory_product_id ON inventory(product_id);
CREATE INDEX idx_inventory_quantity ON inventory(quantity);
CREATE INDEX idx_inventory_updated_at ON inventory(updated_at);