CREATE TABLE IF NOT EXISTS users (
    id SERIAL PRIMARY KEY,
    username VARCHAR(50) UNIQUE NOT NULL,
    email VARCHAR(255) UNIQUE NOT NULL,
    password_hash VARCHAR(255) NOT NULL,
    registrations_remaining INTEGER DEFAULT 3,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS invite_codes (
    id SERIAL PRIMARY KEY,
    code VARCHAR(32) UNIQUE NOT NULL,
    created_by INTEGER REFERENCES users(id),
    used_by INTEGER REFERENCES users(id),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    used_at TIMESTAMP
);

CREATE TABLE IF NOT EXISTS domains (
    id SERIAL PRIMARY KEY,
    name VARCHAR(100) NOT NULL,
    tld VARCHAR(20) NOT NULL,
    ip VARCHAR(255) NOT NULL,
    user_id INTEGER REFERENCES users(id),
    status VARCHAR(20) DEFAULT 'pending',
    denial_reason TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    UNIQUE(name, tld)
);

CREATE INDEX IF NOT EXISTS idx_domains_name_tld ON domains(name, tld);
CREATE INDEX IF NOT EXISTS idx_domains_user_id ON domains(user_id);
CREATE INDEX IF NOT EXISTS idx_domains_status ON domains(status);
CREATE INDEX IF NOT EXISTS idx_users_username ON users(username);
CREATE INDEX IF NOT EXISTS idx_users_email ON users(email);
CREATE INDEX IF NOT EXISTS idx_invite_codes_code ON invite_codes(code);