const test = require('node:test');
const assert = require('node:assert/strict');
const fs = require('node:fs');
const path = require('node:path');
const read = f => fs.readFileSync(path.join(__dirname, '..', f), 'utf8');

// Generated assets are served `private, no-store`, which is correct for a
// clinical app on a shared workstation. The cost was that every gallery render
// re-downloaded every image — 26 images at ~279kB to draw 56px tiles.
test('assets are still never written to disk', () => {
  const route = read('src/routes/generatedImages.js');
  assert.match(route, /Cache-Control', 'private, no-store'/,
    'the no-store posture is unchanged; caching is in memory for the session only');
});

test('the cache is scoped to the account that fetched it', () => {
  const js = read('public/js/generatedImages.js');
  // A cache keyed only by URL would let the next account read the previous
  // one's bytes out of memory.
  assert.match(js, /function cacheKey\(src, ticket\) \{ return String\(ticket && ticket\.ticket\)/,
    'entries are keyed by owner ticket as well as asset');
  assert.match(js, /clearImageCache\(\); \/\/ cached bytes must not outlive the account/,
    'and dropped when the account boundary moves');
  assert.match(js, /assertImageOwner\(ticket\)/, 'ownership is asserted on the way in');
});

test('concurrent tiles share one request instead of racing', () => {
  const js = read('public/js/generatedImages.js');
  assert.match(js, /if \(inflight\.has\(key\)\) return inflight\.get\(key\);/);
  assert.match(js, /\.finally\(\(\) => inflight\.delete\(key\)\)/, 'and the slot is released either way');
});

test('a tile decodes a thumbnail, not a full image', () => {
  const js = read('public/js/generatedImages.js');
  assert.match(js, /const edge = Number\(img\.getAttribute\('data-image-thumb'\)\) \|\| 0;/);
  assert.match(js, /edge \? await cachedThumbnail\(src, edge, ticket\) : await cachedImageBlob\(src, ticket\)/);
  // A browser without OffscreenCanvas still shows the image rather than nothing.
  assert.match(js, /if \(typeof createImageBitmap !== 'function' \|\| typeof OffscreenCanvas !== 'function'\) return blob;/);
  assert.match(js, /catch \(_\) \{\s*\n\s*return blob;/, 'and a decode failure falls back to the original');

  const assistant = read('public/js/clinicalAssistant.js');
  assert.match(assistant, /data-image-thumb="256"/, 'the 56px gallery asks for a small copy');
});