# Classroom printing

The package installs and enables CUPS, its client/filter stack, and Debian's
compressed Foomatic PPD database. Chrome is configured to open the system
print dialog, which shows the queues configured in CUPS.

The Ricoh Aficio MP C3502 supports PCL 5c and PCL 6 as standard; PostScript 3
is optional. Debian Trixie does not provide a model-specific C3502 PPD in the
installed driver set, so the classroom uses Trixie's recommended generic color
PCL 6/PCL XL driver. This uses the printer's standard language and requires no
vendor binary.

## Automatic church printer

Every provisioning pass runs:

```
classroom-printer-setup
```

It creates or updates this site-wide queue:

| Setting | Value |
| --- | --- |
| Queue and display name | `Elmer` |
| Printer | Ricoh Aficio MP C3502 |
| Address | `10.10.0.155` |
| Hardware address | `00:26:73:4F:E7:C9` |
| URI | `socket://10.10.0.155:9100` |
| Default | `Elmer` |
| Print quality | `PrintoutMode=Normal` |
| Color | `ColorModel=Color` |

Those two print options are set explicitly. The generic driver otherwise chose
`Normal.Gray` on the physical printer, which silently made jobs grayscale.

If an older release created `Classroom_Color`, provisioning removes it before
creating Elmer. A correct subsequent run reports that Elmer is already
configured and does not rewrite the queue.

The helper can still take an explicit address for diagnostics or future site
changes:

```
sudo classroom-printer-setup 10.10.0.155
sudo classroom-printer-setup ipp://10.10.0.155/ipp/print
sudo classroom-printer-setup --no-default socket://10.10.0.155:9100
```

The command does not contact the printer while configuring CUPS. An
unreachable printer only leaves jobs queued; the provisioning call is also
capped at 30 seconds, so it cannot affect boot.

## Network printer discovery

Automatic remote queue browsing is disabled. `cups-browsed` is stopped and
disabled, and both `avahi-daemon.service` and `avahi-daemon.socket` are stopped,
disabled and masked. No other classroom component uses Avahi.

This removes the direct DNS-SD destinations that `lpstat -e` can show even when
cups-browsed is inactive, including the Brother check-in printer and the
duplicate discovered Ricoh. The intended output is only:

```
$ lpstat -e
Elmer
```

## Administration

List the available Debian drivers, including the selected PCL path:

```
lpinfo -m
lpinfo -m | grep -i -E 'Ricoh|PCL|PostScript|IPP Everywhere'
```

Show the queue, URI, system default and print defaults:

```
lpstat -p Elmer -v
lpstat -d
lpoptions -p Elmer -l | grep -E '^(PrintoutMode|ColorModel)/'
```

Set the default manually:

```
sudo lpadmin -d Elmer
```

Print CUPS's test page:

```
lp -d Elmer /usr/share/cups/data/testprint
```

Inspect or cancel queued jobs:

```
lpstat -o Elmer
cancel -a Elmer
```

The printer language choice is based on Ricoh's published
[MP C3002/C3502 specifications](https://assets.ricoh-usa.com/j2jqn9lauv41/1CzJla6qwny2d9oBVHHlID/5bfa366a01cf82162ea24287f99c8af9/aficiompc3002.pdf).


## What the teacher sees

The queue is `Elmer`, its Description is `Elmer`, and its **Location is
deliberately blank**. CUPS prints the Location under the queue name in
every print dialog, so anything there becomes a second line the teacher
has to read past. The printer's teacher-facing identity is one word.

`classroom-printer-setup` enforces this idempotently, and its
already-configured check includes the Location, so a machine set up
before this change is corrected on the next run rather than being left
alone as "close enough".

    lpstat -l -p Elmer      # Description: Elmer, Location: (blank)
    lpstat -p -d            # Elmer, and the system default
    lpstat -e               # Elmer, and nothing else