-- Add customers table for tracking buyers
CREATE EXTENSION IF NOT EXISTS "pgcrypto";

CREATE TABLE customers (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    name VARCHAR(255) NOT NULL,
    phone VARCHAR(50),
    city VARCHAR(255),
    notes TEXT,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
);

-- Phone is the natural dedup key
CREATE UNIQUE INDEX idx_customers_phone ON customers (phone) WHERE phone IS NOT NULL;
CREATE INDEX idx_customers_name ON customers (name);