testing 101

Signed-off-by: Kenneth Obsequio <k80308392@gmail.com>

utils/courses/archive.util.js

@@ -3,8 +3,8 @@
 /**
  * Single archive — soft delete one record
  */
-async function archiveOne(Model, options, deletedBy, transaction) {
-  const record = await Model.findOne(options);
+async function archiveOne(Model, where, deletedBy, transaction) {
+  const record = await Model.findOne({ where, transaction });
   if (!record) return null;
   await record.update({ deletedBy: deletedBy ?? null }, { transaction });
   await record.destroy({ transaction });

utils/currency.util.js

@@ -0,0 +1,171 @@
+/***********************************************************************************************************************************************************************
+ * File Name: currency.util.js
+ * Type of Program: Utility
+ * Description: Currency formatting and resolution helpers for backend use (emails, receipts, notifications).
+ *
+ * All format functions accept an optional options object: { locale }
+ *   locale — BCP 47 tag, defaults to 'en-US'
+ *
+ * USD is the platform's base/canonical currency. Plans may carry localized price
+ * overrides (plan_prices table). resolvePrice() applies the COALESCE logic:
+ *   localized override wins → falls back to plan's base price + currency.
+ ***********************************************************************************************************************************************************************/
+'use strict';
+
+// ─── Supported currencies ─────────────────────────────────────────────────────
+
+const SUPPORTED_CURRENCIES = [
+  { code: 'USD', name: 'US Dollar',           symbol: '$'  },
+  { code: 'EUR', name: 'Euro',                symbol: '€'  },
+  { code: 'GBP', name: 'British Pound',       symbol: '£'  },
+  { code: 'CNY', name: 'Chinese Yuan',        symbol: '¥'  },
+  { code: 'JPY', name: 'Japanese Yen',        symbol: '¥'  },
+  { code: 'PHP', name: 'Philippine Peso',     symbol: '₱'  },
+  { code: 'KRW', name: 'South Korean Won',   symbol: '₩'  },
+  { code: 'AUD', name: 'Australian Dollar',   symbol: 'A$' },
+  { code: 'CAD', name: 'Canadian Dollar',     symbol: 'C$' },
+  { code: 'SGD', name: 'Singapore Dollar',    symbol: 'S$' },
+  { code: 'HKD', name: 'Hong Kong Dollar',    symbol: 'HK$'},
+  { code: 'INR', name: 'Indian Rupee',        symbol: '₹'  },
+  { code: 'MYR', name: 'Malaysian Ringgit',   symbol: 'RM' },
+  { code: 'THB', name: 'Thai Baht',           symbol: '฿'  },
+  { code: 'IDR', name: 'Indonesian Rupiah',   symbol: 'Rp' },
+  { code: 'TWD', name: 'Taiwan Dollar',       symbol: 'NT$'},
+  { code: 'VND', name: 'Vietnamese Dong',     symbol: '₫'  },
+];
+
+const SUPPORTED_CURRENCY_CODES = new Set(SUPPORTED_CURRENCIES.map((c) => c.code));
+
+function isSupported(code) {
+  return SUPPORTED_CURRENCY_CODES.has(code?.toUpperCase());
+}
+
+// ─── Formatting ───────────────────────────────────────────────────────────────
+
+/** "¥1,299.00" / "$9.99" */
+function fmtCurrency(amount, currency = 'USD', { locale = 'en-US' } = {}) {
+  if (amount === null || amount === undefined) return '—';
+  return new Intl.NumberFormat(locale, {
+    style:                 'currency',
+    currency:              currency ?? 'USD',
+    minimumFractionDigits: 2,
+  }).format(Number(amount));
+}
+
+// ─── Price resolution ─────────────────────────────────────────────────────────
+
+/**
+ * Returns the effective { price, currency } for a plan given a user's preferred currency.
+ * plan.prices must be eager-loaded (as: 'prices') for the override to be considered.
+ * Falls back to plan.price + plan.currency when no override exists.
+ */
+function resolvePrice(plan, preferredCurrency) {
+  if (!preferredCurrency || preferredCurrency === plan.currency)
+    return { price: Number(plan.price), currency: plan.currency };
+
+  const override = (plan.prices ?? []).find((p) => p.currency === preferredCurrency);
+  if (override) return { price: Number(override.price), currency: override.currency };
+
+  return { price: Number(plan.price), currency: plan.currency };
+}
+
+// ─── Exchange rate fetching ───────────────────────────────────────────────────
+// Uses frankfurter.app (ECB-backed, no API key, free).
+// In-process cache with 1-hour TTL avoids hammering the API on every save.
+
+const _rateCache = new Map();
+
+async function fetchExchangeRate(from, to) {
+  if (from === to) return 1;
+  const key = `${from}:${to}`;
+  const now = Date.now();
+  const cached = _rateCache.get(key);
+  if (cached && cached.expiresAt > now) return cached.rate;
+
+  try {
+    const res  = await fetch(
+      `https://api.frankfurter.app/latest?from=${from}&to=${to}`,
+      { signal: AbortSignal.timeout(4000) },
+    );
+    if (!res.ok) return null;
+    const json = await res.json();
+    const rate = json?.rates?.[to];
+    if (!rate) return null;
+    _rateCache.set(key, { rate, expiresAt: now + 60 * 60 * 1000 }); // 1 h TTL
+    return rate;
+  } catch {
+    return null;
+  }
+}
+
+// ─── Localized price validation ───────────────────────────────────────────────
+// Three zones relative to the market-rate conversion of the base price:
+//
+//   pass  →  85 % – 150 % of expected  (green, saves normally)
+//   warn  →  70 % – 85 %  or  150 % – 300 %  (saves with caution message)
+//   block →  < 70 %  or  > 300 %  (rejected — too far from market rate)
+//
+// If the exchange-rate API is unavailable the check is skipped (returns 'pass').
+
+const PRICE_ZONES = {
+  LOWER_HARD: 0.70,
+  LOWER_WARN: 0.85,
+  UPPER_WARN: 1.50,
+  UPPER_HARD: 3.00,
+};
+
+async function validateLocalizedPrice(basePrice, baseCurrency, localizedPrice, targetCurrency) {
+  const rate = await fetchExchangeRate(baseCurrency, targetCurrency);
+  if (!rate) return { zone: 'pass', skipped: true };
+
+  const expected = Number(basePrice) * rate;
+  const entered  = Number(localizedPrice);
+  const { LOWER_HARD, LOWER_WARN, UPPER_WARN, UPPER_HARD } = PRICE_ZONES;
+
+  const hardMin = expected * LOWER_HARD;
+  const hardMax = expected * UPPER_HARD;
+  const warnMin = expected * LOWER_WARN;
+  const warnMax = expected * UPPER_WARN;
+
+  const fmt     = (n) => n.toFixed(2);
+  const rateStr = `1 ${baseCurrency} = ${rate} ${targetCurrency}`;
+
+  if (entered < hardMin || entered > hardMax) {
+    return {
+      zone: 'block',
+      expected: fmt(expected),
+      hardMin: fmt(hardMin), hardMax: fmt(hardMax),
+      warnMin: fmt(warnMin), warnMax: fmt(warnMax),
+      message: `${fmt(entered)} ${targetCurrency} is too far from the current market rate (${rateStr}). ` +
+               `Acceptable range: ${fmt(hardMin)} – ${fmt(hardMax)} ${targetCurrency}.`,
+    };
+  }
+
+  if (entered < warnMin || entered > warnMax) {
+    return {
+      zone: 'warn',
+      expected: fmt(expected),
+      hardMin: fmt(hardMin), hardMax: fmt(hardMax),
+      warnMin: fmt(warnMin), warnMax: fmt(warnMax),
+      message: `${fmt(entered)} ${targetCurrency} is outside the suggested range (${rateStr}). ` +
+               `Suggested: ${fmt(warnMin)} – ${fmt(warnMax)} ${targetCurrency}. Saved with caution.`,
+    };
+  }
+
+  return {
+    zone: 'pass',
+    expected: fmt(expected),
+    hardMin: fmt(hardMin), hardMax: fmt(hardMax),
+    warnMin: fmt(warnMin), warnMax: fmt(warnMax),
+  };
+}
+
+module.exports = {
+  SUPPORTED_CURRENCIES,
+  isSupported,
+  fmtCurrency,
+  resolvePrice,
+  fetchExchangeRate,
+  validateLocalizedPrice,
+  PRICE_ZONES,
+};