fix: improve language docs + string parsing

codegen/src/gen_locales.rs

@@ -1,5 +1,7 @@
 use std::collections::BTreeMap;
 use std::fmt::Write;
+use std::fs::File;
+use std::io::BufReader;
 
 use path_macro::path;
 use reqwest::header;
@@ -9,6 +11,7 @@ use serde_with::serde_as;
 use serde_with::VecSkipError;
 
 use crate::model::Text;
+use crate::util::DICT_DIR;
 use crate::util::SRC_DIR;
 
 #[serde_as]
@@ -141,16 +144,41 @@ struct LanguageCountryCommand {
 pub async fn generate_locales() {
     let (languages, countries) = get_locales().await;
 
+    let json_path = path!(*DICT_DIR / "lang_names.json");
+    let json_file = File::open(json_path).unwrap();
+    let lang_names: BTreeMap<String, String> =
+        serde_json::from_reader(BufReader::new(json_file)).unwrap();
+
     let code_head = r#"// This file is automatically generated. DO NOT EDIT.
 
 //! Languages and countries
 
+use std::str::FromStr;
+
 use serde::{Deserialize, Serialize};
 
 use crate::error::Error;
 "#;
 
-    let code_foot = r#"serde_plain::derive_fromstr_from_deserialize!(Language, Error);
+    let code_foot = r#"impl FromStr for Language {
+    type Err = Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut sub = s;
+        loop {
+            if let Ok(v) = serde_plain::from_str(sub) {
+                return Ok(v);
+            }
+            match sub.rfind('-') {
+                Some(pos) => {
+                    sub = &sub[..pos];
+                }
+                None => return Err(Error::Other("could not parse language `{s}`".into())),
+            }
+        }
+    }
+}
+
 serde_plain::derive_display_from_serialize!(Language);
 
 serde_plain::derive_fromstr_from_deserialize!(Country, Error);
@@ -199,8 +227,8 @@ pub enum Country {
 "#
     .to_owned();
 
-    languages.iter().for_each(|(c, n)| {
-        let enum_name = c
+    languages.iter().for_each(|(code, native_name)| {
+        let enum_name = code
             .split('-')
             .map(|c| {
                 format!(
@@ -211,10 +239,16 @@ pub enum Country {
             })
             .collect::<String>();
 
+        let en_name = lang_names.get(code).expect(code);
+
         // Language enum
-        write!(code_langs, "    /// {n}\n    ").unwrap();
-        if c.contains('-') {
-            write!(code_langs, "#[serde(rename = \"{c}\")]\n    ").unwrap();
+        if en_name == native_name || code.starts_with("en") {
+            write!(code_langs, "    /// {native_name}\n    ").unwrap();
+        } else {
+            write!(code_langs, "    /// {en_name} / {native_name}\n    ").unwrap();
+        }
+        if code.contains('-') {
+            write!(code_langs, "#[serde(rename = \"{code}\")]\n    ").unwrap();
         }
         code_langs += &enum_name;
         code_langs += ",\n";
@@ -225,7 +259,7 @@ pub enum Country {
         // Language names
         writeln!(
             code_lang_names,
-            "            Language::{enum_name} => \"{n}\","
+            "            Language::{enum_name} => \"{native_name}\","
         )
         .unwrap();
     });