# CourseHub

Self-hosted course video player: PHP 8 + MySQL/MariaDB + Bootstrap 5 + [Plyr](https://github.com/sampotts/plyr).

Single-page app: `index.php` is a static shell; all navigation, login, browsing,
playback, and scanning happen over AJAX against the JSON API in `api/`
(`auth.php`, `library.php`, `progress.php`, `scan.php`), with hash-based routes
(`#/`, `#/folder/N`, `#/watch/N`) so views switch without page reloads and
browser back/forward still work. Only `stream.php` (the mp4 bytes) is a plain
HTTP resource.

- Recursively scans a videos directory for `.mp4` files and mirrors the folder
  hierarchy (courses → sections → videos, any nesting depth).
- Per-user **resume**: log in from any device and continue where you left off.
- **Progress tracking at every level** — each folder shows completed/total and a
  percentage bar computed over its whole subtree.
- "Continue watching" strip, auto-play next video, playback speed, keyboard
  shortcuts (Plyr), completed checkmarks, natural sorting (`Video2` before `Video10`).
- Seekable streaming via HTTP Range requests; files are addressed by DB id only
  (no path traversal).

## Layout on disk

```
videos/
├── Course 1/
│   ├── Intro/
│   │   ├── Video1.mp4
│   │   └── Video2.mp4
│   └── Module 2/
│       └── Advanced/
│           └── lesson.mp4
└── Course 2/
    └── ...
```

Top-level folders become courses on the home page.

## Setup

1. **Database** — create the schema and an app user:

   ```bash
   sudo mysql < schema.sql
   sudo mysql -e "CREATE USER IF NOT EXISTS 'coursehub'@'localhost' IDENTIFIED BY 'coursehub';
                  GRANT ALL ON coursehub.* TO 'coursehub'@'localhost';"
   ```

2. **Configure** — edit `config.php`:
   - `VIDEOS_ROOT`: absolute path to your course folders (must be readable by
     the web server / PHP user).
   - DB credentials (change the password in production).
   - `ALLOW_REGISTRATION`: set `false` once your users have accounts.

3. **Run** — with the PHP built-in server for testing:

   ```bash
   php -S 0.0.0.0:8080 -t /path/to/coursehub
   ```

   or point an Apache/Nginx + PHP-FPM vhost at the directory.

4. **Index the library** — click **Rescan library** in the top bar, or:

   ```bash
   php scan.php
   ```

   Rescan whenever you add/remove files. Re-scans are idempotent: existing
   videos keep their IDs (and everyone's progress); files that disappeared are
   hidden, not deleted, so progress survives if they come back.

5. Open the site, create an account, and watch.

## How progress works

- The player POSTs `{video_id, position, duration}` to `api/progress.php`
  every 5 s while playing, plus on pause/seek, via `navigator.sendBeacon`
  when the tab is hidden or closed, and when navigating to another view
  in the SPA.
- A video is marked **completed** at ≥ 95 % watched (`COMPLETE_THRESHOLD`).
  Completion is sticky — rewatching doesn't un-complete it.
- Folder progress is computed over the folder's entire subtree using a path
  prefix match, with partial credit for videos in progress.
- Video duration is captured from the browser on first play (no ffprobe
  dependency) and cached on the `videos` row.

## Production notes

- PHP streams the video in 512 KB chunks with Range support, which is fine for
  a handful of users. For heavier use, serve files with `X-Accel-Redirect`
  (Nginx) or `X-Sendfile` (Apache) instead of streaming through PHP.
- Put the app behind HTTPS and set `session.cookie_secure=1`.
- Deny direct web access to `includes/`, `config.php`, and `schema.sql`
  (or place the videos and includes outside the docroot).