import { test } from 'node:test';
import assert from 'node:assert/strict';
import { EncryptedAttachmentInfo } from 'browser-encrypt-attachment';
import { buildCompressedUploadItem } from './msgContent';
import { TUploadItem } from '../../state/room/roomInputDrafts';

// buildCompressedUploadItem decides which bytes are uploaded and which encInfo
// (if any) the resulting m.image event carries. Getting this wrong either leaks
// a plaintext image into an E2EE room or produces an undecryptable attachment.

const enc = (tag: string): EncryptedAttachmentInfo =>
  ({
    v: 'v2',
    key: { alg: 'A256CTR', k: tag },
    iv: `iv-${tag}`,
    hashes: { sha256: `sha-${tag}` },
  }) as unknown as EncryptedAttachmentInfo;

const fakeFile = (name: string, size: number): File =>
  new File([new Uint8Array(size)], name, { type: 'image/jpeg' });

const makeItem = (encInfo?: EncryptedAttachmentInfo): TUploadItem =>
  ({
    file: fakeFile('photo.png', 900),
    originalFile: fakeFile('photo.png', 900),
    encInfo,
    metadata: { markedAsSpoiler: false, compressImage: true },
  }) as unknown as TUploadItem;

test('unencrypted room: compressed item uploads the plain file and carries no encInfo', () => {
  const compressed = fakeFile('photo.jpg', 300);
  const item = buildCompressedUploadItem(makeItem(), compressed);

  assert.equal(item.file, compressed);
  assert.equal(item.originalFile, compressed);
  assert.equal(item.encInfo, undefined);
});

test('encrypted room: compressed item carries the NEW encInfo, never the original one', () => {
  const compressed = fakeFile('photo.jpg', 300);
  const encryptedBlob = fakeFile('photo.jpg', 320);
  const item = buildCompressedUploadItem(makeItem(enc('original')), compressed, {
    file: encryptedBlob,
    encInfo: enc('compressed'),
  });

  // The ciphertext is what gets uploaded; the plaintext stays available for
  // dimensions/blurhash only.
  assert.equal(item.file, encryptedBlob);
  assert.equal(item.originalFile, compressed);
  assert.deepEqual(item.encInfo, enc('compressed'));
  assert.notDeepEqual(item.encInfo, enc('original'));
});

test('encrypted room: an encInfo-less compressed item never inherits the original encInfo', () => {
  // Defensive: even if the caller forgets to re-encrypt, we must not emit the
  // stale encInfo (that is the bug this helper exists to prevent).
  const item = buildCompressedUploadItem(makeItem(enc('original')), fakeFile('photo.jpg', 300));
  assert.equal(item.encInfo, undefined);
});

test('metadata (caption, spoiler) is preserved on the compressed item', () => {
  const base = makeItem();
  base.metadata.caption = 'a caption';
  base.metadata.markedAsSpoiler = true;
  const item = buildCompressedUploadItem(base, fakeFile('photo.jpg', 300));
  assert.equal(item.metadata.caption, 'a caption');
  assert.equal(item.metadata.markedAsSpoiler, true);
});

// getImageMsgContent itself is not covered here: it needs a DOM (loadImageElement).
// Its encInfo branch (content.file vs content.url) is exercised by the sibling
// msgContent.test.ts builders, which share the same shape.