import { useState } from 'react';
import { useLocalStorage } from '@/hooks/useLocalStorage';
import { useCurrentUser } from '@/hooks/useCurrentUser';
import { PLATFORM_OWNER_PUBKEYS, PLATFORM_LIGHTNING_ADDRESS } from '@/hooks/useListingRestrictions';

// ─── Base monthly (30-day) fee per type, in sats ─────────────────────────────
// Actual charge = base × the selected duration tier's multiplier.
export const PLATFORM_FEES = {
  /** Featured event listing */
  featuredEvent: 5000,
  /** Lab Pro profile (coach / filmer / editor / photographer / builder) */
  labProfile: 5000,
  /** Featured shop placement on map */
  featuredShop: 10000,
  /** Featured tour listing */
  featuredTour: 5000,
} as const;

export type FeeType = keyof typeof PLATFORM_FEES;

// ─── Duration tiers ───────────────────────────────────────────────────────────
// Price discrimination: the longer the commitment, the cheaper the effective
// per-day rate. `multiplier` is applied to a type's base monthly price.
//   7d  → 0.4×  (short "try it" window, priced at a premium per-day)
//   30d → 1.0×  (baseline monthly)
//   90d → 2.4×  (season — ~20% per-day discount) ← best value
//   365d→ 8.0×  (year — ~33% per-day discount)
export type DurationTierId = '7d' | '30d' | '90d' | '365d';

export interface DurationTier {
  id: DurationTierId;
  label: string;
  days: number;
  multiplier: number;
  /** Cosmetic "best value" flag for UI. */
  bestValue?: boolean;
}

export const DURATION_TIERS: DurationTier[] = [
  { id: '7d', label: '7 days', days: 7, multiplier: 0.4 },
  { id: '30d', label: '1 month', days: 30, multiplier: 1 },
  { id: '90d', label: '3 months', days: 90, multiplier: 2.4, bestValue: true },
  { id: '365d', label: '12 months', days: 365, multiplier: 8 },
];

export const DEFAULT_TIER_ID: DurationTierId = '30d';

/** Compute the sats price for a fee type at a given duration tier. */
export function tierPriceSats(type: FeeType, tier: DurationTier): number {
  // Round to the nearest 100 sats for tidy amounts.
  return Math.round((PLATFORM_FEES[type] * tier.multiplier) / 100) * 100;
}

/** Effective per-day sats (for "best value" display). */
export function tierPerDaySats(type: FeeType, tier: DurationTier): number {
  return Math.round(tierPriceSats(type, tier) / tier.days);
}

// ─── Display metadata per fee type ───────────────────────────────────────────
export const FEE_META: Record<FeeType, {
  label: string;
  description: string;
  benefit: string;
  emoji: string;
}> = {
  featuredEvent: {
    label: 'Featured Event',
    description: 'Feature your event on SkateSpots',
    benefit: 'Your event appears at the top of the events page',
    emoji: '📅',
  },
  labProfile: {
    label: 'Lab Pro Profile',
    description: 'Feature your services in The Lab',
    benefit: 'Pro badge + featured placement when skaters browse The Lab',
    emoji: '🎓',
  },
  featuredShop: {
    label: 'Featured Shop',
    description: 'Feature your skate shop on the map and directory',
    benefit: 'Verified badge + featured pin on the map',
    emoji: '🏪',
  },
  featuredTour: {
    label: 'Featured Tour',
    description: 'Feature your tour on SkateSpots',
    benefit: 'Pro badge + top placement when skaters browse tours',
    emoji: '🗺️',
  },
};

// ─── localStorage key per fee type + account ─────────────────────────────────
// Scoped by pubkey so one account on a shared device can't inherit another's
// paid status (a device-global key let any later login skip the fee).
function storageKey(type: FeeType, pubkey: string): string {
  return `platform-fee-paid-${type}-${pubkey}`;
}

interface FeeRecord {
  paidAt: number;       // unix ms
  expiresAt: number;    // unix ms
}

// ─── Hook ─────────────────────────────────────────────────────────────────────
export function usePlatformFee(type: FeeType) {
  const { user } = useCurrentUser();
  const [record, setRecord] = useLocalStorage<FeeRecord | null>(storageKey(type, user?.pubkey ?? 'anon'), null);

  // Currently selected duration tier (UI state).
  const [tierId, setTierId] = useState<DurationTierId>(DEFAULT_TIER_ID);
  const tier = DURATION_TIERS.find((t) => t.id === tierId) ?? DURATION_TIERS[1];

  // Platform owners never pay
  const isPlatformOwner = !!user?.pubkey && PLATFORM_OWNER_PUBKEYS.includes(user.pubkey);

  // Is the fee currently active (paid and not expired)?
  const isActive = isPlatformOwner || (
    record !== null &&
    Date.now() < record.expiresAt
  );

  // Days remaining
  const daysRemaining = isActive && record
    ? Math.ceil((record.expiresAt - Date.now()) / (24 * 60 * 60 * 1000))
    : 0;

  // Expiry as unix SECONDS, for writing into a `featured` event tag.
  // Platform owners get a long-lived (1 year) featured window.
  const featuredUntilSeconds = (() => {
    if (isPlatformOwner) {
      return Math.floor((Date.now() + 365 * 24 * 60 * 60 * 1000) / 1000);
    }
    if (record) return Math.floor(record.expiresAt / 1000);
    return undefined;
  })();

  // Price for the currently selected tier.
  const amountSats = tierPriceSats(type, tier);

  // Record a successful payment for the selected tier's duration.
  const recordPayment = () => {
    const now = Date.now();
    setRecord({
      paidAt: now,
      expiresAt: now + tier.days * 24 * 60 * 60 * 1000,
    });
  };

  return {
    /** Amount in sats for the selected tier */
    amountSats,
    /** Lightning address to pay */
    recipient: PLATFORM_LIGHTNING_ADDRESS,
    recipientName: 'SkateSpots',
    /** Display metadata */
    meta: FEE_META[type],
    /** Available duration tiers */
    tiers: DURATION_TIERS,
    /** Currently selected tier */
    tier,
    /** Change the selected tier */
    setTierId,
    /** Is fee currently paid and active? */
    isActive,
    /** Days remaining on active fee */
    daysRemaining,
    /** Expiry in unix seconds — write into a `featured` tag when publishing */
    featuredUntilSeconds,
    /** Platform owners bypass everything */
    isPlatformOwner,
    /** Call this after successful payment */
    recordPayment,
    /** Price/per-day helpers for UI */
    tierPriceSats: (t: DurationTier) => tierPriceSats(type, t),
    tierPerDaySats: (t: DurationTier) => tierPerDaySats(type, t),
  };
}