Build bilingual Astro exchange landing page and brand reference

scripts/generate-tokens.mjs

@@ -0,0 +1,14 @@
+import { readFileSync, writeFileSync } from 'node:fs';
+const tokens = JSON.parse(
+  readFileSync(new URL('../design/tokens.json', import.meta.url), 'utf8'),
+);
+const kebab = (name) => name.replace(/[A-Z]/g, (c) => `-${c.toLowerCase()}`);
+const colors = Object.entries(tokens.colors);
+writeFileSync(
+  new URL('../src/styles/tokens.css', import.meta.url),
+  `/* Generated by npm run tokens. Edit design/tokens.json. */\n:root {\n${colors.map(([k, v]) => `  --${kebab(k)}: ${v};`).join('\n')}\n  --radius: ${tokens.website.radius.card}px;\n  --font-family: '${tokens.typography.family}', Arial, sans-serif;\n}\n`,
+);
+writeFileSync(
+  new URL('../flutter/brand_palette.dart', import.meta.url),
+  `// Generated brand palette reference. Optional for the Flutter application.\n// This is not an application theme: choose component styling independently.\nimport 'dart:ui';\n\nabstract final class SxchngeBrand {\n${colors.map(([k, v]) => `  static const ${k} = Color(0xFF${v.slice(1).toUpperCase()});`).join('\n')}\n  static const fontFamily = '${tokens.typography.family}';\n}\n`,
+);

scripts/quote.test.mjs

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+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { calculateQuote, parseAmount } from '../src/lib/quote.ts';
+test('demo calculation deducts the example fee in currency cents', () => {
+  assert.deepEqual(calculateQuote(1, 'BTC', 'EUR'), {
+    rate: 57500,
+    fee: 575,
+    receive: 56925,
+    demo: true,
+  });
+  assert.deepEqual(calculateQuote(2, 'ETH', 'USD'), {
+    rate: 2500,
+    fee: 50,
+    receive: 4950,
+    demo: true,
+  });
+  const q = calculateQuote(123.45, 'USDT', 'EUR');
+  assert.equal(q.fee, 1.14);
+  assert.equal(q.receive, 112.43);
+});
+test('accepts decimal comma and eight crypto decimal places', () => {
+  assert.equal(parseAmount(' 0,25 '), 0.25);
+  assert.equal(parseAmount('0.00000001'), 0.00000001);
+  assert.equal(
+    calculateQuote(parseAmount('0,25'), 'BTC', 'EUR').receive,
+    14231.25,
+  );
+});
+test('rejects ambiguous, malformed, excessive or invalid input', () => {
+  for (const value of [
+    '',
+    '-1',
+    '1e3',
+    '1,2,3',
+    '1.2.3',
+    '<script>',
+    '0.000000001',
+    '1 000',
+  ])
+    assert.ok(Number.isNaN(parseAmount(value)));
+  for (const amount of [0, -1, NaN, Infinity, 1000001])
+    assert.throws(() => calculateQuote(amount, 'BTC', 'EUR'), RangeError);
+  assert.throws(() => calculateQuote(1, 'BOGUS', 'EUR'), RangeError);
+  assert.throws(() => calculateQuote(1, 'BTC', 'BOGUS'), RangeError);
+});