// Circle Suite — Traffic Desk. Places member banner ads on the team's own
// NetworkAdSpace network through the signed bridge API (rmc-api on that host).
//
// Two deliberate constraints:
//  1. Creative comes from the TEAM banner kit only. Members never upload art.
//     That removes moderation risk entirely — every ad on the network carries
//     approved branding — and it means a member can launch in two clicks.
//  2. Allowances scale with contract level and are counted per calendar month
//     against a local ledger, so a member cannot spend more than their level.
'use strict';
const fs = require('fs');
const path = require('path');
const crypto = require('crypto');
const suiteGrants = require('./suite-grants');

let DATA_DIR = null;
function init(opts) { DATA_DIR = opts.dataDir; }
function credsFile() { return path.join(DATA_DIR, 'nas-api.json'); }
function creds() { try { return JSON.parse(fs.readFileSync(credsFile(), 'utf8')); } catch (e) { return null; } }
function configured() { const c = creds(); return !!(c && c.url && c.secret); }

// Monthly impressions by contract level (index = level-1). Marty-approved.
const ALLOWANCE = [2500, 5000, 10000, 20000, 50000, 75000, 100000, 150000];
function allowanceFor(level) {
  const n = Math.max(1, Math.min(8, Number(level) || 1));
  return ALLOWANCE[n - 1];
}

// Team banner kit — every ad uses approved creative, so nothing needs review.
const CREATIVES = {
  '468x60':  [ 'rmc-468x60-v1.png', 'rmc-468x60-v2.png', 'rmc-468x60-v3.png', 'rmc-468x60-v4.png',
               'rmc-468x60-v5.png', 'rmc-468x60-v6.png', 'rmc-468x60-v7.png', 'rmc-growing-468x60-bluegreen.png' ],
  '728x90':  [ 'rmc-728x90-v1.png', 'rmc-728x90-v2.png', 'rmc-728x90-v3.png' ],
  '300x250': [ 'rmc-300x250-v1.png', 'rmc-300x250-v3.png', 'rmc-300x250-v4.png' ],
  '160x600': [ 'rmc-160x600-v1.png', 'rmc-160x600-v2.png', 'rmc-160x600-v3.png' ],
  '120x600': [ 'rmc-120x600-v1.png', 'rmc-120x600-v2.png' ],
  '125x125': [ 'rmc-banner-125x125.png' ]
};
function sizes() { return Object.keys(CREATIVES); }

// ── local ledger: what each position has been granted this month ────────────
function ledgerFile() { return path.join(DATA_DIR, 'traffic-grants.json'); }
function readLedger() { try { return JSON.parse(fs.readFileSync(ledgerFile(), 'utf8')); } catch (e) { return {}; } }
function writeLedger(v) { try { fs.writeFileSync(ledgerFile(), JSON.stringify(v)); } catch (e) {} }
function monthKey() { const d = new Date(); return d.getUTCFullYear() + '-' + String(d.getUTCMonth() + 1).padStart(2, '0'); }

function usage(memberId) {
  const all = readLedger();
  const rows = ((all[monthKey()] || {})[String(memberId)]) || [];
  const used = rows.reduce(function (s, r) { return s + (Number(r.impressions) || 0); }, 0);
  return { used: used, campaigns: rows };
}

function status(memberId, level) {
  const base = allowanceFor(level);
  // Impressions an upline granted this month sit on top of the level allowance.
  let granted = 0;
  try { granted = suiteGrants.receivedBy(memberId, 'traffic') || 0; } catch (e) {}
  const limit = base + granted;
  const u = usage(memberId);
  return {
    limit: limit, base: base, granted: granted,
    used: u.used, remaining: Math.max(0, limit - u.used),
    campaigns: u.campaigns, resets: monthKey(), sizes: sizes(), creatives: CREATIVES
  };
}

function record(memberId, entry) {
  const all = readLedger();
  const mk = monthKey();
  if (!all[mk]) all[mk] = {};
  const id = String(memberId);
  if (!all[mk][id]) all[mk][id] = [];
  all[mk][id].push(entry);
  // keep three months of history; the file stays small forever
  const keep = Object.keys(all).sort().slice(-3);
  const trimmed = {};
  keep.forEach(function (k) { trimmed[k] = all[k]; });
  writeLedger(trimmed);
}

// `remaining` counts DOWN for BOTH placement types — measured across 1,604
// network ads, and it is exactly what the bridge's stats action already
// computes (`served = assigned - remaining`, falling back to hits when
// assigned was never set). Trust the bridge's `served` field first.
//
// The earlier "banners count UP" theory (and its ad-2707 evidence) was the
// network's own post-insert counter top-ups being misread; acting on it made
// every fresh banner look fully delivered the moment it launched, so the
// sweeper deactivated brand-new campaigns and stamped them complete (bug
// Marty caught 2026-09-01: a banner "delivered all its impressions"
// instantly). Do not resurrect the count-up branch.
//
// Returns what the member should see: served + left always reconciles to what
// they bought, and neither can exceed it.
function interpret(kind, bought, stat) {
  const b = Math.max(0, Number(bought) || 0);
  let served;
  if (stat && stat.served != null) {
    served = Number(stat.served) || 0;
  } else {
    // count-down: what is gone is what was bought minus what is left
    const rem = Math.max(0, Number(stat && stat.remaining) || 0);
    served = b - Math.min(rem, b);
  }
  served = Math.max(0, Math.min(served, b));
  return { served: served, left: Math.max(0, b - served) };
}

// ── signed call to the NAS bridge ───────────────────────────────────────────
function callNas(payload) {
  return new Promise(function (resolve, reject) {
    const c = creds();
    if (!c) return reject(new Error('The ad network bridge is not configured yet.'));
    const body = JSON.stringify(payload);
    const ts = String(Math.floor(Date.now() / 1000));
    const sig = crypto.createHmac('sha256', c.secret).update(ts + '.' + body).digest('hex');
    const u = new URL(c.url);
    const lib = u.protocol === 'https:' ? require('https') : require('http');
    const req = lib.request({
      hostname: u.hostname, port: u.port || (u.protocol === 'https:' ? 443 : 80),
      path: u.pathname + (u.search || ''), method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Content-Length': Buffer.byteLength(body),
        'X-RMC-Signature': sig,
        'X-RMC-Timestamp': ts,
        'User-Agent': 'RMCircleSuite/1.0'
      }
    }, function (res) {
      let data = '';
      res.on('data', function (d) { data += d; });
      res.on('end', function () {
        let j = null;
        try { j = JSON.parse(data); } catch (e) { return reject(new Error('The ad network returned something unexpected.')); }
        if (!j.ok) return reject(new Error(j.error || 'The ad network rejected that.'));
        resolve(j);
      });
    });
    req.on('error', function (e) { reject(new Error('Could not reach the ad network: ' + e.message)); });
    req.setTimeout(45000, function () { req.destroy(new Error('The ad network took too long.')); });
    req.write(body); req.end();
  });
}

async function launch(opts) {
  const level = Number(opts.level) || 1;
  const isText = opts.kind === 'text';
  let size = '', file = '', subject = '', lines = [];

  if (isText) {
    // Limits measured from live network inventory — see suite-textads.js.
    subject = String(opts.subject || '').trim();
    lines = (Array.isArray(opts.lines) ? opts.lines : []).slice(0, 3)
      .map(function (l) { return String(l || '').replace(/[<>]/g, '').trim(); });
    while (lines.length < 3) lines.push('');
    if (!subject || !lines[0]) throw new Error('That text ad is missing its headline or first line.');
    if (Array.from(subject).length > 20) throw new Error('The headline is longer than the network allows.');
    if (lines.some(function (l) { return Array.from(l).length > 24; })) {
      throw new Error('One of those lines is longer than the network allows.');
    }
  } else {
    size = String(opts.size || '');
    if (!CREATIVES[size]) throw new Error('Pick one of the available banner sizes.');
    file = String(opts.creative || '');
    if (CREATIVES[size].indexOf(file) === -1) throw new Error('Pick one of the team banner designs.');
  }

  const st = status(opts.id, level);
  const impressions = Math.max(100, Math.min(st.limit, Number(opts.impressions) || 0));
  if (impressions > st.remaining) {
    throw new Error('That is more than your remaining ' + st.remaining.toLocaleString() + ' impressions this month.');
  }

  // Server-side guard: only allow the personal page as a destination when one
  // actually exists. /p/<id> also redirects to /join/<id> when empty, so a live
  // banner can never dead-end — but we shouldn't create that situation at all.
  let target = 'https://rmcircle.team/join/' + opts.id + (opts.angle ? '?v=' + opts.angle : '');
  if (opts.target === 'page') {
    if (!opts.hasPage) throw new Error('Build your personal page first, then you can point ads at it.');
    target = 'https://rmcircle.team/p/' + opts.id;
  }
  // Tag the destination so a click can be traced back to this network.
  //
  // Without this the Traffic Desk is unmeasurable: track.js reads ?v= BEFORE
  // it reads the referrer, so every angle-linked ad click was filed under
  // "angle:graveyard" and the referring domain thrown away. Ad clicks, flyer
  // QR scans and massifly angle links all landed in the same four buckets,
  // and networkadspace.com showed a grand total of 1 visit across ~45,000
  // served impressions — not because the ads produced nothing, but because
  // nothing carried a source.
  //
  // `src` wins over `v` in track.js, and the landing page still reads ?v=
  // separately, so the hook keeps working. Split by format because we believe
  // text outperforms banners and have never been able to show it.
  target += (target.indexOf('?') === -1 ? '?' : '&') + 'src=nas-' + (isText ? 'text' : 'banner');

  const idem = 'rmc-' + opts.id + '-' + monthKey() + '-' + crypto.randomBytes(6).toString('hex');
  const payload = {
    action: 'create', member_id: Number(opts.id), idem_key: idem,
    kind: isText ? 'text' : 'banner',
    // 30 days, not 365: the allowance is monthly, so a campaign that outlives the
    // month it was paid from makes the allowance meaningless. Belt and braces
    // with sweepCompleted() — whichever ends it first.
    impressions: impressions, days: 30, target_url: target,
    advertiser_name: (opts.name || 'RM Circle member #' + opts.id).slice(0, 60),
    advertiser_email: '', catid: 5
  };
  if (isText) {
    payload.subject = subject;
    payload.lines = lines;
  } else {
    payload.size = size;
    payload.banner_url = 'https://rmcircle.team/banners/' + file;
  }
  const res = await callNas(payload);

  const entry = {
    adId: res.ad_id, impressions: impressions,
    size: isText ? 'text' : size, creative: isText ? '' : file,
    kind: isText ? 'text' : 'banner',
    subject: isText ? subject : undefined,
    lines: isText ? lines : undefined,
    target: target, at: new Date().toISOString()
  };
  record(opts.id, entry);
  return entry;
}

// Stop a running banner and return the UNSERVED impressions to the member's
// monthly balance. Order matters: read the counters BEFORE deactivating,
// because deactivation zeroes `remaining` and would make it look fully served.
async function stop(memberId, adId) {
  const all = readLedger();
  const mk = monthKey();
  const rows = ((all[mk] || {})[String(memberId)]) || [];
  const pre = rows.find(function (r) { return Number(r.adId) === Number(adId); });
  if (!pre) throw new Error('That banner is not one of yours from this month.');
  if (pre.stopped) throw new Error('That banner is already stopped.');

  let served = 0, unserved = 0;
  const boughtGuess = Number(pre.bought != null ? pre.bought : pre.impressions) || 0;
  try {
    const s = await callNas({ action: 'stats', ad_ids: [Number(adId)] });
    const st = (s.stats || [])[0];
    if (st) {
      // Interpret by placement type — banners count up, text counts down.
      const r = interpret(pre.kind === 'text' ? 'text' : 'banner', boughtGuess, st);
      served = r.served;
      unserved = r.left;
    }
  } catch (e) {
    // Stats unavailable: refund nothing rather than guess. Guessing high would
    // hand back impressions that were actually delivered.
    served = boughtGuess; unserved = 0;
  }

  await callNas({ action: 'deactivate', ad_id: Number(adId) });

  // RE-READ before writing. Everything above this point took two network round
  // trips to the ad network, and the ledger object read at the top of this
  // function is now seconds stale. Writing it back would silently discard any
  // campaign another member launched in the meantime — impressions spent on the
  // network with no record that they were. Node's single thread makes the block
  // below atomic; the danger was only ever the await gap.
  const fresh = readLedger();
  const freshRows = ((fresh[mk] || {})[String(memberId)]) || [];
  const row2 = freshRows.find(function (r) { return Number(r.adId) === Number(adId); });
  if (!row2) throw new Error('That banner is no longer in this month\'s ledger.');
  if (row2.stopped) return { adId: Number(adId), served: row2.served || 0, refunded: row2.refunded || 0 };

  const all2 = fresh;
  const row = row2;

  // Charge only what actually served; the rest returns to the allowance.
  // `bought` preserves the original order size so the member's history still
  // shows what they launched, not just what it ended up costing them.
  if (row.bought == null) row.bought = row.impressions;

  // interpret() already reconciled these against what was bought.
  unserved = Math.min(unserved, row.bought);
  served = row.bought - unserved;
  row.stopped = true;
  row.stoppedAt = new Date().toISOString();
  row.served = served;
  row.refunded = unserved;
  row.impressions = served;   // what this campaign counts against the month
  writeLedger(all2);
  return { adId: Number(adId), served: served, refunded: unserved };
}

async function stats(adIds) {
  if (!adIds || !adIds.length) return [];
  const r = await callNas({ action: 'stats', ad_ids: adIds.slice(0, 200) });
  return r.stats || [];
}

// Deactivate anything that has delivered what was bought.
//
// This exists because banner placements on this network have NO CAP: the
// counter runs past the purchase and the ad keeps rotating until its expiry
// date. Left alone that quietly destroys the whole point of the allowance —
// if 2,500 impressions buys an ad that runs forever, nobody would ever spend
// 50,000, and the level ladder from Scintilla to Corona stops meaning
// anything. The impressions have to be the thing you are actually spending.
//
// Runs on a timer, batches its reads, and is deliberately conservative: it
// only ever touches campaigns that are live, un-stopped, and provably at or
// past their purchased amount. Nothing is refunded — they delivered in full.
async function sweepCompleted() {
  if (!configured()) return { checked: 0, closed: 0 };
  const all = readLedger();
  const mk = monthKey();
  const month = all[mk] || {};
  const live = [];
  Object.keys(month).forEach(function (mid) {
    (month[mid] || []).forEach(function (r) {
      if (!r.stopped && !r.completed && r.adId) live.push({ mid: mid, row: r });
    });
  });
  if (!live.length) return { checked: 0, closed: 0 };

  const byId = {};
  for (let i = 0; i < live.length; i += 150) {
    try {
      const chunk = await stats(live.slice(i, i + 150).map(function (x) { return x.adId || x.row.adId; }));
      chunk.forEach(function (st) { byId[st.ad_id] = st; });
    } catch (e) { return { checked: live.length, closed: 0, error: e.message }; }
  }

  let closed = 0;
  for (const item of live) {
    const r = item.row;
    const st = byId[r.adId];
    if (!st || !st.live) continue;
    const bought = Number(r.bought != null ? r.bought : r.impressions) || 0;
    if (!bought) continue;
    const got = interpret(r.kind === 'text' ? 'text' : 'banner', bought, st);
    if (got.served < bought) continue;
    try { await callNas({ action: 'deactivate', ad_id: Number(r.adId) }); }
    catch (e) { continue; }
    closed++;
  }

  if (closed) {
    // Re-read: the deactivate calls above took real time, and another member
    // may have launched in that window.
    const fresh = readLedger();
    const fm = fresh[mk] || {};
    Object.keys(fm).forEach(function (mid) {
      (fm[mid] || []).forEach(function (r) {
        const hit = live.find(function (x) { return x.row.adId === r.adId; });
        if (!hit) return;
        const st = byId[r.adId];
        if (!st || !st.live) return;
        const bought = Number(r.bought != null ? r.bought : r.impressions) || 0;
        if (!bought) return;
        if (interpret(r.kind === 'text' ? 'text' : 'banner', bought, st).served < bought) return;
        r.completed = true;
        r.completedAt = new Date().toISOString();
        r.served = bought;
      });
    });
    writeLedger(fresh);
  }
  return { checked: live.length, closed: closed };
}

module.exports = { init, configured, status, launch, stop, stats, interpret, sweepCompleted, allowanceFor, sizes, CREATIVES, ALLOWANCE };