// Default AI model for all tiers (can override in user settings on PRO)
const DEFAULT_AI_MODEL = 'openai/gpt-4o-mini';

// Subscription tier limits
export const SUBSCRIPTION_LIMITS = {
  FREE: {
    coursesPerMonth: 2,
    defaultAiModel: DEFAULT_AI_MODEL,
  },
  PREMIUM: {
    coursesPerMonth: 5,
    defaultAiModel: DEFAULT_AI_MODEL,
  },
  PRO: {
    coursesPerMonth: 15,
    defaultAiModel: DEFAULT_AI_MODEL,
  },
} as const;

// Prices in RUB for Russian locale (approximate)
const PRICE_RUB = {
  FREE: 0,
  PREMIUM: 999,
  PRO: 2999,
} as const;

// Subscription plans for display
export const SUBSCRIPTION_PLANS = [
  {
    tier: 'FREE' as const,
    name: 'Free',
    nameRu: 'Бесплатный',
    description: 'Perfect for trying out CourseCraft',
    descriptionRu: 'Идеально для знакомства с CourseCraft',
    price: 0,
    priceRu: PRICE_RUB.FREE,
    currency: 'USD',
    features: [
      '2 courses per month',
      'Basic AI model',
      'Standard support',
    ],
    featuresRu: [
      '2 курса в месяц',
      'Базовая нейросеть',
      'Стандартная поддержка',
    ],
    stripePriceId: null,
  },
  {
    tier: 'PREMIUM' as const,
    name: 'Premium',
    nameRu: 'Премиум',
    description: 'For creators who need more',
    descriptionRu: 'Для тех, кому нужно больше',
    price: 9.99,
    priceRu: PRICE_RUB.PREMIUM,
    currency: 'USD',
    features: [
      '5 courses per month',
      'Enhanced AI model',
      'Priority support',
      'Advanced editing tools',
    ],
    featuresRu: [
      '5 курсов в месяц',
      'Улучшенная нейросеть',
      'Приоритетная поддержка',
      'Расширенные инструменты редактирования',
    ],
    stripePriceId: process.env.STRIPE_PRICE_PREMIUM || null,
  },
  {
    tier: 'PRO' as const,
    name: 'Pro',
    nameRu: 'Профессиональный',
    description: 'For power users and teams',
    descriptionRu: 'Для профессионалов и команд',
    price: 29.99,
    priceRu: PRICE_RUB.PRO,
    currency: 'USD',
    features: [
      '15 courses per month',
      'Best AI model available',
      'Priority support 24/7',
      'Advanced editing tools',
      'Custom AI model selection',
      'Export to PDF (coming soon)',
    ],
    featuresRu: [
      '15 курсов в месяц',
      'Лучшая доступная нейросеть',
      'Приоритетная поддержка 24/7',
      'Расширенные инструменты редактирования',
      'Выбор модели нейросети',
      'Экспорт в PDF (скоро)',
    ],
    stripePriceId: process.env.STRIPE_PRICE_PRO || null,
  },
] as const;

export type SubscriptionPlan = (typeof SUBSCRIPTION_PLANS)[number];

/** Format plan price for display. Uses RUB when language is Russian. */
export function formatPlanPrice(
  plan: { price: number; priceRu: number; currency: string },
  language: string
): { amount: number; currency: string; formatted: string } {
  const isRu = language === 'ru' || language.startsWith('ru');
  if (isRu) {
    const amount = plan.priceRu;
    return {
      amount,
      currency: 'RUB',
      formatted: amount === 0 ? 'Бесплатно' : `${amount.toLocaleString('ru-RU')} ₽`,
    };
  }
  return {
    amount: plan.price,
    currency: plan.currency,
    formatted: plan.price === 0 ? 'Free' : `$${plan.price}`,
  };
}

// Generation progress steps
export const GENERATION_STEPS = {
  PENDING: { progress: 0, label: 'Waiting to start', labelRu: 'Ожидание запуска' },
  ANALYZING: { progress: 10, label: 'Analyzing your request', labelRu: 'Анализ запроса' },
  ASKING_QUESTIONS: { progress: 15, label: 'Preparing questions', labelRu: 'Подготовка вопросов' },
  WAITING_FOR_ANSWERS: { progress: 20, label: 'Waiting for your answers', labelRu: 'Ожидание ваших ответов' },
  RESEARCHING: { progress: 30, label: 'Researching the topic', labelRu: 'Исследование темы' },
  GENERATING_OUTLINE: { progress: 50, label: 'Creating course structure', labelRu: 'Создание структуры курса' },
  GENERATING_CONTENT: { progress: 70, label: 'Writing course content', labelRu: 'Написание содержания' },
  COMPLETED: { progress: 100, label: 'Course completed!', labelRu: 'Курс готов!' },
  FAILED: { progress: 0, label: 'Generation failed', labelRu: 'Ошибка генерации' },
  CANCELLED: { progress: 0, label: 'Generation cancelled', labelRu: 'Генерация отменена' },
} as const;

// API Routes
export const API_ROUTES = {
  AUTH: {
    ME: '/auth/me',
    CALLBACK: '/auth/callback',
    LOGOUT: '/auth/logout',
  },
  USERS: {
    PROFILE: '/users/profile',
    SETTINGS: '/users/settings',
  },
  COURSES: {
    LIST: '/courses',
    CREATE: '/courses',
    GET: (id: string) => `/courses/${id}`,
    UPDATE: (id: string) => `/courses/${id}`,
    DELETE: (id: string) => `/courses/${id}`,
  },
  CHAPTERS: {
    LIST: (courseId: string) => `/courses/${courseId}/chapters`,
    CREATE: (courseId: string) => `/courses/${courseId}/chapters`,
    UPDATE: (courseId: string, chapterId: string) => `/courses/${courseId}/chapters/${chapterId}`,
    DELETE: (courseId: string, chapterId: string) => `/courses/${courseId}/chapters/${chapterId}`,
    REORDER: (courseId: string) => `/courses/${courseId}/chapters/reorder`,
  },
  LESSONS: {
    GET: (courseId: string, lessonId: string) => `/courses/${courseId}/lessons/${lessonId}`,
    UPDATE: (courseId: string, lessonId: string) => `/courses/${courseId}/lessons/${lessonId}`,
  },
  GENERATION: {
    START: '/generation/start',
    STATUS: (id: string) => `/generation/${id}/status`,
    ANSWER: (id: string) => `/generation/${id}/answer`,
    CANCEL: (id: string) => `/generation/${id}/cancel`,
  },
  SUBSCRIPTIONS: {
    PLANS: '/subscriptions/plans',
    CURRENT: '/subscriptions/current',
    CHECKOUT: '/subscriptions/checkout',
    PORTAL: '/subscriptions/portal',
  },
  SEARCH: {
    COURSES: '/search/courses',
  },
} as const;

// Validation
export const VALIDATION = {
  COURSE: {
    TITLE_MIN: 3,
    TITLE_MAX: 200,
    DESCRIPTION_MAX: 5000,
  },
  CHAPTER: {
    TITLE_MIN: 2,
    TITLE_MAX: 200,
  },
  LESSON: {
    TITLE_MIN: 2,
    TITLE_MAX: 200,
  },
  PROMPT: {
    MIN: 10,
    MAX: 2000,
  },
} as const;