i18n: Spanish translations for error and status-bar messages

apps/vectorcraft-web/src/main.rs

@@ -11,7 +11,8 @@
 //! - Save / Export trigger a browser download;
 //! - dropped files are read asynchronously by `web::WebShell` and delivered through the inbox.
 //!
-//! URL query flag: `?webgl` forces the WebGL2 backend instead of WebGPU.
+//! URL query flags: `?webgl` forces the WebGL2 backend instead of WebGPU; `?lang=es` (any
+//! language code) stands in for the browser's languages when the interface language is Automatic.
 
 #[cfg(target_arch = "wasm32")]
 mod locks;

apps/vectorcraft-web/src/web.rs

@@ -9,6 +9,7 @@ use vectorcraft_engine::Session;
 use vectorcraft_engine::cmd::fileio;
 use vectorcraft_engine::cmd::recovery::{self, Hold, RecoveryStore};
 use vectorcraft_ui_egui::graphics::GraphicsLoss;
+use vectorcraft_ui_egui::i18n;
 use vectorcraft_ui_egui::place::{DropTarget, PlaceArrival, PlaceInbox};
 use vectorcraft_ui_egui::print::{PrintJob, PrintService, Printer};
 use vectorcraft_ui_egui::{Services, VectorcraftApp};
@@ -49,6 +50,7 @@ pub fn start() {
         log::error!("missing <canvas id=\"{CANVAS_ID}\">");
         return;
     };
+    detect_language();
     wasm_bindgen_futures::spawn_local(async move {
         // Before the first frame, which looks for copies a crash left behind.
         let locks = WebLocks::start(RECOVERY_PREFIX).await;
@@ -131,6 +133,27 @@ fn web_options() -> eframe::WebOptions {
     options
 }
 
+/// Tell the UI the browser's languages (`?lang=es` in the address first, as `VECTORCRAFT_LOCALE`
+/// does on the desktop) before the first frame, so the Automatic interface language follows the
+/// browser; and show the loading text in that language.
+fn detect_language() {
+    let mut tags: Vec<String> = query_param("lang").into_iter().collect();
+    if let Some(navigator) = web_sys::window().map(|w| w.navigator()) {
+        tags.extend(navigator.languages().iter().filter_map(|v| v.as_string()));
+        tags.extend(navigator.language());
+    }
+    i18n::set_system_locales(tags.as_slice());
+    if let Some(el) = element(LOADING_ID) {
+        el.set_text_content(Some(i18n::message(i18n::system_lang(), "Loading VectorCraft…").as_str()));
+    }
+}
+
+/// The value of `name=` in the address's query, if given.
+fn query_param(name: &str) -> Option<String> {
+    let query = query();
+    query.trim_start_matches('?').split('&').find_map(|kv| kv.strip_prefix(name)?.strip_prefix('=').map(str::to_string)).filter(|v| !v.is_empty())
+}
+
 fn query() -> String {
     web_sys::window().and_then(|w| w.location().search().ok()).unwrap_or_default()
 }
@@ -215,7 +238,7 @@ fn notice(lines: &[&str]) {
     el.set_text_content(None);
     for line in lines {
         if let Ok(p) = document.create_element("p") {
-            p.set_text_content(Some(line));
+            p.set_text_content(Some(i18n::message(i18n::system_lang(), line).as_str()));
             // Best effort: the log has the message too.
             el.append_child(&p).ok();
         }