// Leaderboard, badges and share links. All derived from the payout ledger; nothing new is stored.
//
// A "find" is any non-failed payout (paid, sent, due or queued): the hunter did the work. POL counts
// paid drips only, so the board never shows money that has not left the faucet. Days and weeks are
// Central (ctDay), the same clock as the pool.
//
// settings.leaderboardExclude: member ids kept off the public boards (default: the company account #1).
'use strict';
const store = require('./store');
const { ctDay } = require('./missions');
const rewards = require('./rewards');
const missions = require('./missions');

const BADGES = [
  { id: 'first', name: 'First Find', icon: '\u{1F3AF}', why: 'your first code claimed' },
  { id: 'hunter', name: 'Hunter', icon: '\u{1F9ED}', why: 'five finds' },
  { id: 'tracker', name: 'Tracker', icon: '\u{1F526}', why: 'twenty finds' },
  { id: 'sweep', name: 'Full Sweep', icon: '\u{1F5FA}️', why: 'a find on every site' },
  { id: 'lucky', name: 'Lucky Find', icon: '\u{1F48E}', why: 'one drip of 0.4 POL or more' },
  { id: 'streak', name: 'On a Streak', icon: '\u{1F525}', why: 'finds on three days in a row' },
  { id: 'top', name: 'Top Hunter', icon: '\u{1F3C6}', why: 'won a weekly prize as #1' },
  { id: 'recruiter', name: 'Recruiter', icon: '\u{1F91D}', why: 'brought a hunter who found their first code' },
];
const PRIZE_DEFAULTS = { weeklyPrizes: [3, 2, 1], weeklyMinFinds: 10 };
function prizeRules() { const s = rewards.settings(); return { pol: Array.isArray(s.weeklyPrizes) && s.weeklyPrizes.length ? s.weeklyPrizes.map(Number) : PRIZE_DEFAULTS.weeklyPrizes, minFinds: Number(s.weeklyMinFinds) > 0 ? Number(s.weeklyMinFinds) : PRIZE_DEFAULTS.weeklyMinFinds }; }

function excluded() { const s = rewards.settings(); const list = Array.isArray(s.leaderboardExclude) ? s.leaderboardExclude : [1]; return new Set(list.map(Number)); }
function finds() { return store.read('payouts', []).filter(p => p.status !== 'failed' && !p.prize && !p.ref); } // prize drips are not finds

// Central day arithmetic on 'YYYY-MM-DD' keys
function dayMinus(dayKey, n) { const [y, m, d] = dayKey.split('-').map(Number); const t = Date.UTC(y, m - 1, d) - n * 86400000; return new Date(t).toISOString().slice(0, 10); }
// the Monday that starts a day's week (weeks run Monday to Sunday, Central)
function weekOf(dayKey) { const [y, m, d] = dayKey.split('-').map(Number); const dow = (new Date(Date.UTC(y, m - 1, d)).getUTCDay() + 6) % 7; return dayMinus(dayKey, dow); }
function inPeriod(p, period, today) {
  if (period === 'all') return true;
  if (period === 'month') return p.day.slice(0, 7) === today.slice(0, 7);
  return weekOf(p.day) === weekOf(today); // week: this Monday-to-Sunday week
}

function badgesFor(memberId, list) {
  const mine = (list || finds()).filter(p => p.memberId === Number(memberId));
  if (!mine.length) return [];
  const out = new Set();
  out.add('first');
  if (mine.length >= 5) out.add('hunter');
  if (mine.length >= 20) out.add('tracker');
  const sites = new Set(missions.list().filter(m => m.active !== false).map(m => m.site));
  if (sites.size && [...sites].every(s => mine.some(p => p.site === s))) out.add('sweep');
  if (mine.some(p => p.pol >= 0.4)) out.add('lucky');
  const days = new Set(mine.map(p => p.day));
  for (const d of days) { if (days.has(dayMinus(d, 1)) && days.has(dayMinus(d, 2))) { out.add('streak'); break; } }
  if (store.read('payouts', []).some(p => p.memberId === Number(memberId) && p.prize && p.prize.rank === 1 && p.status !== 'failed')) out.add('top');
  // earned by a bounty, not a match: someone they brought turned up and found their first code
  if (store.read('payouts', []).some(p => p.memberId === Number(memberId) && p.ref && p.ref.kind === 'bounty' && p.status !== 'failed')) out.add('recruiter');
  return BADGES.filter(b => out.has(b.id));
}

function leaderboard(period, limit) {
  const today = ctDay(); const ex = excluded(); const all = finds();
  const by = new Map();
  for (const p of all) {
    if (ex.has(p.memberId) || !inPeriod(p, period, today)) continue;
    const r = by.get(p.memberId) || { memberId: p.memberId, who: p.username ? '@' + p.username : '#' + p.memberId, finds: 0, pol: 0, last: 0 };
    r.finds++; if (p.status === 'paid') r.pol += p.pol; r.last = Math.max(r.last, p.at); by.set(p.memberId, r);
  }
  const rows = [...by.values()].sort((a, b) => b.finds - a.finds || b.pol - a.pol || a.last - b.last);
  return rows.slice(0, limit || 25).map((r, i) => Object.assign(r, { rank: i + 1, pol: Math.round(r.pol * 10000) / 10000, badges: badgesFor(r.memberId, all).map(b => b.icon) }));
}

// standings for one fixed week (Monday key), qualified by the minimum finds
function weekRows(monday) {
  const ex = excluded(); const all = finds(); const end = dayMinus(monday, -6); const by = new Map();
  for (const p of all) {
    if (ex.has(p.memberId) || p.day < monday || p.day > end) continue;
    const r = by.get(p.memberId) || { memberId: p.memberId, who: p.username ? '@' + p.username : '#' + p.memberId, username: p.username || null, email: p.email, wallet: p.wallet, finds: 0, pol: 0, last: 0 };
    r.finds++; if (p.status === 'paid') r.pol += p.pol; r.last = Math.max(r.last, p.at); if (p.wallet) r.wallet = p.wallet; by.set(p.memberId, r);
  }
  return [...by.values()].sort((a, b) => b.finds - a.finds || b.pol - a.pol || a.last - b.last);
}
// award one week, once: prize drips go on the ledger as due, the faucet pays them like any drip
function awardWeek(monday) {
  if (!/^\d{4}-\d{2}-\d{2}$/.test(monday || '') || weekOf(monday) !== monday) return { error: 'not a Monday key' };
  const done = store.read('prizes', []);
  if (done.some(x => x.week === monday)) return { skipped: 'already awarded', week: monday };
  const rules = prizeRules();
  const winners = weekRows(monday).filter(r => r.finds >= rules.minFinds).slice(0, rules.pol.length).map((r, i) => Object.assign({ rank: i + 1, prizePol: rules.pol[i] }, r));
  const day = ctDay(), at = Date.now();
  const recs = winners.map(w => ({ id: 'prize' + monday.replace(/-/g, '') + '-' + w.rank, memberId: w.memberId, email: w.email, wallet: w.wallet, username: w.username, missionId: 'prize:' + monday, site: 'Weekly prize #' + w.rank, pol: w.prizePol, day, at, status: 'due', tx: null, paidAt: null, error: null, prize: { week: monday, rank: w.rank } }));
  if (recs.length) store.update('payouts', [], all => { all.push(...recs); return all; });
  const entry = { week: monday, at, rules, winners: winners.map(w => ({ rank: w.rank, memberId: w.memberId, who: w.who, finds: w.finds, pol: w.pol, prizePol: w.prizePol })) };
  store.update('prizes', [], all => { all.push(entry); return all; });
  return entry;
}
// on every tick: the most recent completed week gets awarded on the first tick after it ends
function awardDue(notify) {
  const last = dayMinus(weekOf(ctDay()), 7);
  if (store.read('prizes', []).some(x => x.week === last)) return null;
  const r = awardWeek(last);
  if (r && r.winners && r.winners.length && notify) notify('prize', r).catch(() => {});
  return r;
}
function prizes() { const all = store.read('prizes', []); return { rules: prizeRules(), week: weekOf(ctDay()), last: all.length ? all[all.length - 1] : null, history: all.slice(-8).reverse() }; }

function rankOf(memberId, period) {
  const rows = leaderboard(period, 100000); const i = rows.findIndex(r => r.memberId === Number(memberId));
  return i < 0 ? null : { rank: i + 1, of: rows.length, finds: rows[i].finds, pol: rows[i].pol };
}

// the member's share link: PolHunter's landing with their IAP referral, which the landing turns into
// their instantadpay.com/join/<ref> link for everyone who signs up from it
// the public name used in share URLs: the IAP username, else m<memberId>; and back again
function nameOf(me) { return me.username ? String(me.username).toLowerCase() : 'm' + me.memberId; }
function memberByName(who) {
  const w = String(who || '').toLowerCase(); if (!w) return null;
  const all = store.read('payouts', []);
  const p = all.find(x => (x.username && String(x.username).toLowerCase() === w) || 'm' + x.memberId === w);
  return p ? { memberId: p.memberId, username: p.username || null, who: p.username ? '@' + p.username : '#' + p.memberId } : null;
}
function shareLink(site, me) { const ref = me.username || me.memberId; return site + '/?r=' + encodeURIComponent(String(ref)); }

module.exports = { BADGES, badgesFor, leaderboard, rankOf, shareLink, weekOf, weekRows, awardWeek, awardDue, prizes, prizeRules, nameOf, memberByName };