export type PlanId = 'free' | 'pro';

export type Plan = {
  id: PlanId;
  name: string;
  price: number;
  /** Monthly included usage per metric. */
  limits: { seats: number; apiCalls: number };
  features: string[];
};

export const PLANS: Record<PlanId, Plan> = {
  free: {
    id: 'free',
    name: 'Free',
    price: 0,
    limits: { seats: 2, apiCalls: 1_000 },
    features: ['Up to 2 members', '1,000 API calls / month', 'Community support'],
  },
  pro: {
    id: 'pro',
    name: 'Pro',
    price: 29,
    limits: { seats: 25, apiCalls: 100_000 },
    features: ['Up to 25 members', '100,000 API calls / month', 'Priority support'],
  },
};

export const PLAN_IDS: PlanId[] = ['free', 'pro'];

export function isPlanId(value: unknown): value is PlanId {
  return value === 'free' || value === 'pro';
}

export function getPlan(value: unknown): Plan {
  return isPlanId(value) ? PLANS[value] : PLANS.free;
}

export function withinLimit(plan: unknown, metric: keyof Plan['limits'], used: number): boolean {
  return used < getPlan(plan).limits[metric];
}

export function formatCurrency(amount: number, currency = 'USD'): string {
  return new Intl.NumberFormat('en-US', { style: 'currency', currency }).format(amount);
}

export function formatDate(value: Date | string): string {
  const d = typeof value === 'string' ? new Date(value) : value;
  return new Intl.DateTimeFormat('en-US', { dateStyle: 'medium' }).format(d);
}

export function slugify(value: string): string {
  return value
    .toLowerCase()
    .trim()
    .replace(/[^a-z0-9]+/g, '-')
    .replace(/^-+|-+$/g, '');
}