// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.

import { describe, expect, it } from 'vitest';

import { DesktopFileNodeParser } from '../src/onenote/onestore/file-node.js';
import { OneNoteParserError } from '../src/onenote/parser/error.js';
import { resolveParserLimits } from '../src/onenote/parser/limits.js';

const MAGIC = 0xa4567ab1f5f7f4c4n;
const FOOTER = 0x8bc215c38233ba4bn;

describe('DesktopFileNodeParser', () => {
  it('rejects a multi-fragment cycle immediately', () => {
    const bytes = new Uint8Array(72);
    writeFragment(bytes, 0, 0x10, 0, 36);
    writeFragment(bytes, 36, 0x10, 1, 0);

    const parser = new DesktopFileNodeParser(bytes, resolveParserLimits());
    const parse = () =>
      parser.parseList({ offset: 0, size: 36, nil: false, zero: false });

    expect(parse).toThrowError(OneNoteParserError);
    expect(parse).toThrow(/cycle/i);
  });

  it('stops decoding at ChunkTerminatorFND and permits an opaque tail', () => {
    const bytes = new Uint8Array(52);
    const view = new DataView(bytes.buffer);
    view.setBigUint64(0, MAGIC, true);
    view.setUint32(8, 0x10, true);
    view.setUint32(12, 0, true);
    view.setUint32(16, 0x10ff, true); // id 0xff, declared size 4
    bytes.fill(0xa5, 20, 32); // deliberately not valid FileNode words
    view.setBigUint64(32, 0xffffffffffffffffn, true);
    view.setUint32(40, 0, true);
    view.setBigUint64(44, FOOTER, true);

    const parser = new DesktopFileNodeParser(bytes, resolveParserLimits());
    const parsed = parser.parseList({
      offset: 0,
      size: bytes.length,
      nil: false,
      zero: false,
    });

    expect(parsed.nodes).toEqual([]);
  });

  it('uses the transaction-log count to delimit nonzero fragment padding', () => {
    const bytes = new Uint8Array(52);
    const view = new DataView(bytes.buffer);
    view.setBigUint64(0, MAGIC, true);
    view.setUint32(8, 0x10, true);
    view.setUint32(12, 0, true);
    view.setUint32(16, 0x1004, true); // id 4, declared size 4
    bytes.fill(0xa5, 20, 32); // opaque tail without a terminator
    view.setBigUint64(32, 0xffffffffffffffffn, true);
    view.setUint32(40, 0, true);
    view.setBigUint64(44, FOOTER, true);

    const parser = new DesktopFileNodeParser(
      bytes,
      resolveParserLimits(),
      new Map([[0x10, 1]])
    );
    const parsed = parser.parseList({
      offset: 0,
      size: bytes.length,
      nil: false,
      zero: false,
    });

    expect(parsed.nodes.map(({ id }) => id)).toEqual([0x004]);
  });
});

function writeFragment(
  bytes: Uint8Array,
  offset: number,
  listId: number,
  sequence: number,
  nextOffset: number
): void {
  const view = new DataView(bytes.buffer, offset, 36);
  view.setBigUint64(0, MAGIC, true);
  view.setUint32(8, listId, true);
  view.setUint32(12, sequence, true);
  view.setBigUint64(16, BigInt(nextOffset), true);
  view.setUint32(24, 36, true);
  view.setBigUint64(28, FOOTER, true);
}