= Development guide
:toc:
:toclevels: 2

== Web app only

[source,shell]
----
bundle install
bundle exec puma -C config/puma.rb
----

Open http://127.0.0.1:4567. For auto-reload during development, run
via the `rerun` gem instead:

[source,shell]
----
bundle exec rerun -- bundle exec puma -C config/puma.rb
----

TIP: Browsers apply heuristic caching to static files even without
explicit cache headers, so an edit to `public/` (or `views/`) can
appear not to have taken effect on the next reload. Force a real
reload (e.g. Ctrl/Cmd+Shift+R) if that happens.

== Offline map data

To enable the offline style, place a PMTiles file at
`data/offline.pmtiles` (see `docs/architecture.adoc` for how it is
served and styled). It is not part of the repository — obtain or
build one locally:

* The simplest source is a pre-built extract from
  https://app.protomaps.com[protomaps.com's extract builder] — pick a
  region and download it as `.pmtiles`. Its schema is what
  `protomaps-themes-base` (the styling library used for the offline
  style) expects.
* To convert some other vector tile source (e.g. an `.mbtiles` file)
  into PMTiles, use the
  https://github.com/protomaps/go-pmtiles[go-pmtiles] CLI:
  `pmtiles convert in.mbtiles data/offline.pmtiles`.

Once the file is in place, `GET /api/offline-tiles` reports
`available: true` and the map defaults to the offline style.

This is picked up automatically for `cargo tauri dev` (it just runs
the Sinatra app from the project root). To ship it inside a *packaged*
build, add it to `bundle.resources` in `src-tauri/tauri.conf.json`:
`"../data/offline.pmtiles": "data/offline.pmtiles"`. Not added by
default, since these files can be large and are picked per
deployment.

== Desktop shell (Tauri)

=== Prerequisites

* Rust (stable) and the Tauri CLI: `cargo install tauri-cli --version "^2"`
* Ruby + Bundler, with gems installed (`bundle install` in the project
  root)
* Platform build tools required by Tauri itself:
** *Linux*: WebKitGTK and GTK development packages, e.g. on
   Debian/Ubuntu:
+
[source,shell]
----
sudo apt install libwebkit2gtk-4.1-dev libjavascriptcoregtk-4.1-dev \
  libgtk-3-dev libsoup-3.0-dev build-essential
----
** *macOS*: Xcode command line tools.
** *Windows*: the WebView2 runtime (preinstalled on current Windows) and
   the MSVC build tools.

See the upstream https://tauri.app/start/prerequisites/[Tauri
prerequisites] page for the current package names on your platform.

=== Running in development

[source,shell]
----
cd src-tauri
cargo tauri dev
----

This runs `beforeDevCommand` (starts Puma on `127.0.0.1:4567`) and
opens a native window pointed at it, per `src-tauri/tauri.conf.json`.

=== Building

[source,shell]
----
cd src-tauri
cargo tauri build
----

Requires `Gemfile.lock` to exist (`bundle install` beforehand), since
the Ruby app files are embedded into the bundle as resources. See
`docs/architecture.adoc` for the current limitation around this build
still depending on a system Ruby installation on the target machine.

=== Regenerating icons

Desktop icons live in `src-tauri/icons/`. To regenerate them from a
new source image (at least 1024x1024 PNG):

[source,shell]
----
cd src-tauri
cargo tauri icon path/to/source.png
----