요금제 설계 (Free/Basic/Pro)

-- 요금제 테이블
CREATE TABLE plans (
    id              INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    name            VARCHAR(50) NOT NULL,           -- 'free', 'basic', 'pro'
    display_name    VARCHAR(100) NOT NULL,          -- '무료', '베이직', '프로'
    price_monthly   INT UNSIGNED NOT NULL DEFAULT 0,  -- 월 가격 (원)
    price_yearly    INT UNSIGNED NOT NULL DEFAULT 0,  -- 연 가격 (원, 할인 적용)
    api_calls_limit INT UNSIGNED NOT NULL DEFAULT 0,  -- 월 API 호출 한도 (0=무제한)
    storage_mb      INT UNSIGNED NOT NULL DEFAULT 0,  -- 스토리지 한도 (MB)
    max_users       INT UNSIGNED NOT NULL DEFAULT 1,  -- 최대 사용자 수
    features_json   JSON NOT NULL,                     -- 기능 플래그 JSON
    sort_order      TINYINT UNSIGNED DEFAULT 0,
    is_active       TINYINT(1) DEFAULT 1,
    created_at      DATETIME DEFAULT CURRENT_TIMESTAMP
);

-- 기본 요금제 데이터 삽입
INSERT INTO plans (name, display_name, price_monthly, price_yearly, api_calls_limit, storage_mb, max_users, features_json, sort_order) VALUES
('free',  '무료',    0,      0,       100,   100,   1, '{"ai_agent":false,"custom_domain":false,"api_access":false,"support":"community","analytics":"basic"}', 1),
('basic', '베이직',  100000, 960000,  5000,  5000,  5, '{"ai_agent":true,"custom_domain":false,"api_access":true,"support":"email","analytics":"advanced"}',  2),
('pro',   '프로',    250000, 2400000, 0,     50000, 20, '{"ai_agent":true,"custom_domain":true,"api_access":true,"support":"priority","analytics":"full"}',   3);

-- 구독(결제) 테이블
CREATE TABLE subscriptions (
    id              INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    tenant_id       INT UNSIGNED NOT NULL,
    plan_id         INT UNSIGNED NOT NULL,
    billing_cycle   ENUM('monthly','yearly') DEFAULT 'monthly',
    status          ENUM('active','past_due','cancelled','trialing') DEFAULT 'active',
    current_period_start DATETIME NOT NULL,
    current_period_end   DATETIME NOT NULL,
    cancelled_at    DATETIME DEFAULT NULL,
    created_at      DATETIME DEFAULT CURRENT_TIMESTAMP,

    FOREIGN KEY (tenant_id) REFERENCES tenants(id),
    FOREIGN KEY (plan_id) REFERENCES plans(id),
    INDEX idx_tenant_status (tenant_id, status)
);