-- Add paid_amount to invoices
ALTER TABLE invoices ADD COLUMN paid_amount DECIMAL(15,2) DEFAULT 0.00 AFTER total_with_vat;

-- Create payments table
CREATE TABLE IF NOT EXISTS payments (
    id INT AUTO_INCREMENT PRIMARY KEY,
    invoice_id INT NOT NULL,
    payment_date DATE NOT NULL,
    amount DECIMAL(15,2) NOT NULL,
    payment_method VARCHAR(50) DEFAULT 'Cash',
    notes TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (invoice_id) REFERENCES invoices(id) ON DELETE CASCADE
);