CREATE TABLE IF NOT EXISTS admin_users (
    id BIGSERIAL PRIMARY KEY,
    username VARCHAR(100) NOT NULL UNIQUE,
    password_hash TEXT NOT NULL,
    is_active BOOLEAN NOT NULL DEFAULT TRUE,
    created_at TIMESTAMP NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS auth_sessions (
    id BIGSERIAL PRIMARY KEY,
    user_id BIGINT NOT NULL REFERENCES admin_users(id) ON DELETE CASCADE,
    session_token TEXT NOT NULL UNIQUE,
    created_at TIMESTAMP NOT NULL DEFAULT NOW(),
    last_activity_at TIMESTAMP NOT NULL DEFAULT NOW(),
    expires_at TIMESTAMP NOT NULL,
    revoked_at TIMESTAMP NULL,
    ip_address VARCHAR(100),
    user_agent TEXT
);

CREATE INDEX IF NOT EXISTS idx_auth_sessions_token ON auth_sessions(session_token);
CREATE INDEX IF NOT EXISTS idx_auth_sessions_user_id ON auth_sessions(user_id);
CREATE INDEX IF NOT EXISTS idx_auth_sessions_last_activity ON auth_sessions(last_activity_at);