feat(i18n): added automatic default launcher language selection

Improved `i18n` mod to list supported languages and some other stuff

As well was added `get_default_lang` function
which will return language key based on current system language.
This function is called at the first launcher start
to update default `launcher.language` config property, so user will immediately
have proper language in initial setup window

src/background.rs

@@ -8,20 +8,9 @@ pub struct Background {
 }
 
 pub fn get_uri() -> String {
-    let mut lang;
-
-    unsafe {
-        lang = crate::i18n::LANG.language.as_str().to_string();
-
-        if let Some(region) = crate::i18n::LANG.region {
-            lang += "-";
-            lang += &region.as_str().to_ascii_lowercase();
-        }
-    }
-
     let uri = concat!("https://sdk-os-static.", "ho", "yo", "verse", ".com/hk4e_global/mdk/launcher/api/content?filter_adv=true&key=gcStgarh&launcher_id=10&language=");
 
-    uri.to_owned() + &lang
+    uri.to_owned() + crate::i18n::get_lang()
 }
 
 #[cached::proc_macro::cached(result)]

src/i18n.rs

@@ -8,17 +8,88 @@ fluent_templates::static_loader! {
     };
 }
 
-pub static mut LANG: LanguageIdentifier = langid!("en");
+/// Map of supported languages
+pub const SUPPORTED_LANGUAGES: &[(&str, LanguageIdentifier)] = &[
+    ("en-us", langid!("en")),
+    ("ru-ru", langid!("ru"))
+];
 
+static mut LANG: LanguageIdentifier = langid!("en");
+
+/// Set launcher language
+pub fn set_lang<T: AsRef<str>>(lang: T) -> anyhow::Result<()> {
+    for (key, id) in SUPPORTED_LANGUAGES {
+        if key == &lang.as_ref() {
+            unsafe {
+                LANG = id.to_owned()
+            }
+
+            return Ok(());
+        }
+    }
+
+    anyhow::bail!("Language {} is not supported", lang.as_ref())
+}
+
+/// Get launcher language
+pub fn get_lang() -> &'static str {
+    for (key, lang) in SUPPORTED_LANGUAGES {
+        if lang == unsafe { &LANG } {
+            return key;
+        }
+    }
+
+    unreachable!()
+}
+
+/// Get system language or default language if system one is not supported
+/// 
+/// Checks env variables in following order:
+/// - `LC_ALL`
+/// - `LC_MESSAGES`
+/// - `LANG`
+pub fn get_default_lang() -> String {
+    let lang = std::env::var("LC_ALL")
+        .unwrap_or_else(|_| std::env::var("LC_MESSAGES")
+        .unwrap_or_else(|_| std::env::var("LANG")
+        .unwrap_or_else(|_| String::from("en_US.UTF-8"))));
+
+    let lang = lang.split('.')
+        .next()
+        .unwrap_or("en_US")
+        .replace('_', "-")
+        .to_ascii_lowercase();
+
+    for (key, _) in SUPPORTED_LANGUAGES {
+        if key == &lang {
+            return lang;
+        }
+    }
+
+    String::from("en-us")
+}
+
+/// Get translated message by key
+/// 
+/// ```no_run
+/// println!("Translated message: {}", tr("launch"));
+/// ``` 
 #[allow(clippy::expect_fun_call)]
 pub fn tr(id: &str) -> String {
     unsafe {
         LOCALES
             .lookup(&LANG, id)
-            .expect(&format!("Failed to find message with a given id: {id}"))
+            .expect(&format!("Failed to find message with given id: {id}"))
     }
 }
 
+/// Get translated message by key with filled arguments
+/// 
+/// ```no_run
+/// println!("Translated message: {}", tr_args("game-outdated", [
+///     ("latest", "3.3.0".into())
+/// ]));
+/// ``` 
 #[allow(clippy::expect_fun_call)]
 pub fn tr_args<I, T>(id: &str, args: I) -> String
 where
@@ -28,6 +99,6 @@ where
     unsafe {
         LOCALES
             .lookup_with_args(&LANG, id, &std::collections::HashMap::from_iter(args.into_iter()))
-            .expect(&format!("Failed to find message with a given id: {id}"))
+            .expect(&format!("Failed to find message with given id: {id}"))
     }
 }

src/main.rs

@@ -65,6 +65,13 @@ fn main() {
 
         // This one is kinda critical buy well, I can't do something with it
         std::fs::write(FIRST_RUN_FILE.as_path(), "").expect("Failed to create .first-run file");
+
+        // Set initial launcher language based on system language
+        let mut config = config::get().expect("Failed to get config");
+
+        config.launcher.language = i18n::get_default_lang();
+
+        config::update_raw(config).expect("Failed to update config");
     }
 
     // Force debug output
@@ -130,7 +137,12 @@ fn main() {
             background-size: cover;
         }}
     ", BACKGROUND_FILE.to_string_lossy()));
-    
+
+    // Set UI language
+    i18n::set_lang(config::get().unwrap().launcher.language).expect("Failed to set launcher language");
+
+    tracing::info!("Set UI language to {}", i18n::get_lang());
+
     // Run FirstRun window if .first-run file persist
     if FIRST_RUN_FILE.exists() {
         app.run::<ui::first_run::main::FirstRunApp>(());
@@ -138,13 +150,6 @@ fn main() {
 
     // Run the app if everything's ready
     else {
-        // Set UI language
-        unsafe {
-            i18n::LANG = config::get().unwrap().launcher.language.parse().unwrap();
-
-            tracing::info!("Set UI language to {}", i18n::LANG);
-        }
-
         app.run::<ui::main::App>(());
     }
 }