CREATE TABLE IF NOT EXISTS stock_categories (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name_en VARCHAR(255) NOT NULL,
    name_ar VARCHAR(255) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS stock_units (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name_en VARCHAR(255) NOT NULL,
    name_ar VARCHAR(255) NOT NULL,
    short_name_en VARCHAR(50) NOT NULL,
    short_name_ar VARCHAR(50) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS stock_items (
    id INT AUTO_INCREMENT PRIMARY KEY,
    category_id INT,
    unit_id INT,
    name_en VARCHAR(255) NOT NULL,
    name_ar VARCHAR(255) NOT NULL,
    sku VARCHAR(100) UNIQUE,
    purchase_price DECIMAL(15, 2) DEFAULT 0.00,
    sale_price DECIMAL(15, 2) DEFAULT 0.00,
    stock_quantity DECIMAL(15, 2) DEFAULT 0.00,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (category_id) REFERENCES stock_categories(id) ON DELETE SET NULL,
    FOREIGN KEY (unit_id) REFERENCES stock_units(id) ON DELETE SET NULL
);