# Cosmic Weather Applet

A weather applet for the [COSMIC](https://github.com/pop-os/cosmic-epoch) desktop environment that displays current conditions in the panel and a full forecast in a popup. Weather data is provided by [wttr.in](https://wttr.in) using IP-based geolocation.

## Building

Requires a Rust toolchain and the following system dependencies:

```sh
# Debian/Ubuntu
sudo apt-get install pkg-config libxkbcommon-dev libwayland-dev
```

Install Rust via [rustup](https://rustup.rs/) if needed, then:

```sh
cargo build --release
```

## Testing

For development, `cargo run` launches the applet in a standalone window in the center of the display. It behaves the same as when embedded in the panel.

```sh
cargo run
```

## Deploying

To deploy to your local user session, build a release binary, replace the running instance, and restart the panel so it picks up the new binary:

```sh
cargo build --release
cp target/release/cosmic-weather-applet ~/.local/bin/
# Restart the applet and panel
killall cosmic-weather-applet
killall cosmic-panel
```

The panel will relaunch automatically and load the updated applet.

## Configuration

### Temperature and wind units

By default, the applet lets [wttr.in](https://wttr.in) pick units based on
your IP-based location (so users in the US get Fahrenheit, everyone else
gets Celsius).

At startup the applet additionally inspects your measurement locale
(`LC_MEASUREMENT`, then `LC_ALL`, then `LANG`). Locales in the US,
Liberia, the Bahamas, Belize, the Cayman Islands, and Palau are requested
as Fahrenheit / USCS; all other locales fall through to the wttr.in
default.

To override the choice explicitly, set `COSMIC_WEATHER_UNITS`:

| Value  | Meaning                                   |
| ------ | ----------------------------------------- |
| `u`    | Fahrenheit, mph (USCS)                    |
| `m`    | Celsius, km/h (metric)                    |
| `M`    | Celsius, m/s                              |
| `auto` | (or unset) Use locale / geolocation       |

Because the applet is launched by `cosmic-panel`, a persistent override
is easiest to set on that service, e.g.:

```sh
systemctl --user edit cosmic-panel
# In the override file:
# [Service]
# Environment=COSMIC_WEATHER_UNITS=u

systemctl --user restart cosmic-panel
```

Changes take effect after the applet is restarted.

## Localization

[Fluent](https://projectfluent.org/) is used for localization. Translation files are in the [i18n directory](./i18n). To add a new language, copy the [English (en) localization](./i18n/en), rename the directory to the target [ISO 639-1 language code](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes), and translate the message values.