CONTRIBUTING.md

Contributing to Simple Video Download Helper

First off, thank you for taking the time to contribute! 🎉 Contributions of all kinds are welcome — bug reports, feature requests, documentation, new site parsers, translations and code.

This document explains how to get set up and the conventions we follow.

Table of Contents

• Code of Conduct
• Ways to Contribute
• Project Layout
• Development Setup
• Available Scripts
• Coding Standards
• Adding a New Site Parser
• Adding or Updating a Translation
• Commit Messages
• Pull Request Process

Code of Conduct

By participating in this project you agree to uphold a respectful, harassment- free environment for everyone. Please be kind and constructive.

Ways to Contribute

• Report bugs using the bug report template.
• Request features using the feature request template.
• Improve documentation — even fixing a typo helps.
• Add support for a new site — see below.
• Translate the UI — see below.

Project Layout

The extension and all of its tooling live in the video-url-parser/ directory. The repository root exposes the same npm scripts and delegates into that directory, so you can work from either location.

.
├── package.json               # Root scripts that delegate into video-url-parser/
└── video-url-parser/          # The extension itself
    ├── manifest.json          # Manifest V3 definition
    ├── js/
    │   ├── functions.js       # Core helper utilities (unit-tested)
    │   ├── constants.js       # Shared constants (unit-tested)
    │   └── parsevideo.js      # The ParseVideo engine and site parsers (unit-tested)
    ├── lang/                  # Popup UI translations (one file per language)
    ├── _locales/              # Chrome i18n messages (one folder per locale)
    └── test/                  # Mocha + Chai unit tests

Development Setup

Requirements: Node.js >= 18.

# Clone your fork
git clone https://github.com/<your-username>/VideoDownloadHelper.git
cd VideoDownloadHelper

# Install dependencies (root delegates into video-url-parser/)
npm install

To load the extension in your browser:

cd video-url-parser
npm run build              # produces dist/dist.min.js (not committed)

Then open chrome://extensions, enable Developer mode, click Load unpacked and select the video-url-parser/ folder.

To create the Chrome Web Store zip package instead, run:

npm run package            # writes simple-video-download-helper-<version>.zip at the repo root

Available Scripts

Run these from the repository root or from video-url-parser/:

Script	Description
npm test	Run the Mocha unit-test suite.
npm run coverage	Run the tests and enforce coverage thresholds.
npm run lint	Lint the source and tests with ESLint.
npm run lint:fix	Auto-fix lint problems where possible.
npm run format	Format the codebase with Prettier.
npm run format:check	Verify formatting without writing changes.
npm run build	Produce the production bundle.
npm run package	Build and create the extension zip at the repo root.
npm run check	Run lint, format check, coverage and build.

Before opening a pull request, please make sure npm run check passes.

Coding Standards

• Code style is enforced by ESLint (flat config) and Prettier: 4-space indentation, double quotes, semicolons, 120-character print width.
• The linters and formatter are intentionally scoped to the core library (js/functions.js, js/constants.js, js/parsevideo.js), the test suite and the config files. Vendored libraries and legacy UI scripts are excluded — see eslint.config.js and .prettierignore. Please keep those ignore lists in sync when you add files.
• New behaviour in the core library should be covered by unit tests.
• The parser must remain dependency-free at runtime.

Adding a New Site Parser

1. Add a parse_<site>_com(...) function in video-url-parser/js/parsevideo.js and register it in the Parse() chain.
2. Add a spec file under video-url-parser/test/ (e.g. test_parsevideo_<site>.js) with representative HTML fixtures in test/data/.
3. Add the verified page to tested-urls.txt.
4. Run npm run check and update the "Supported sites" table in the README.

Adding or Updating a Translation

The popup UI is translated via two mechanisms:

• video-url-parser/lang/<code>.js — the popup UI strings. Copy lang/en-us.js, translate each value, and keep the same set of keys.
• video-url-parser/_locales/<locale>/messages.json — the Chrome extension name/description shown in the browser.

When you add a new language to lang/, also:

1. Add a <script src="lang/<code>.js"></script> include in main.html.
2. Add a case "<code>": return (translation_<name>); in js/translate.js (get_lang()).
3. Add an <option value="<code>">Native name</option> to the language <select id="lang"> in main.html.

Commit Messages

• Use clear, imperative subject lines (e.g. "Add Vietnamese translation").
• Reference related issues where relevant (e.g. "Fixes #123").
• Keep unrelated changes in separate commits/PRs.

Pull Request Process

1. Fork the repository and create a topic branch from master.
2. Make your change, adding tests and documentation as appropriate.
3. Ensure npm run check passes locally.
4. Open a pull request using the template and describe what and why.
5. Be responsive to review feedback — we're glad to help get your change merged.

Thank you for contributing! ❤️