Add options to specify audio & subtitle locales as IETF language tag and add --language_tagging flag for archive and download to modify the output file language tagging (#330)

crunchy-cli-core/src/utils/locale.rs

@@ -1,4 +1,124 @@
 use crunchyroll_rs::Locale;
+use log::warn;
+
+#[derive(Clone, Debug)]
+#[allow(clippy::upper_case_acronyms)]
+pub enum LanguageTagging {
+    Default,
+    IETF,
+}
+
+impl LanguageTagging {
+    pub fn parse(s: &str) -> Result<Self, String> {
+        Ok(match s.to_lowercase().as_str() {
+            "default" => Self::Default,
+            "ietf" => Self::IETF,
+            _ => return Err(format!("'{}' is not a valid language tagging", s)),
+        })
+    }
+
+    pub fn convert_locales(&self, locales: &[Locale]) -> Vec<String> {
+        let ietf_language_codes = ietf_language_codes();
+        let mut converted = vec![];
+
+        match &self {
+            LanguageTagging::Default => {
+                for locale in locales {
+                    let Some((_, available)) =
+                        ietf_language_codes.iter().find(|(_, l)| l.contains(locale))
+                    else {
+                        // if no matching IETF language code was found, just pass it as it is
+                        converted.push(locale.to_string());
+                        continue;
+                    };
+                    converted.push(available.first().unwrap().to_string())
+                }
+            }
+            LanguageTagging::IETF => {
+                for locale in locales {
+                    let Some((tag, _)) =
+                        ietf_language_codes.iter().find(|(_, l)| l.contains(locale))
+                    else {
+                        // if no matching IETF language code was found, just pass it as it is
+                        converted.push(locale.to_string());
+                        continue;
+                    };
+                    converted.push(tag.to_string())
+                }
+            }
+        }
+
+        converted
+    }
+
+    pub fn for_locale(&self, locale: &Locale) -> String {
+        match &self {
+            LanguageTagging::Default => ietf_language_codes()
+                .iter()
+                .find(|(_, l)| l.contains(locale))
+                .map_or(locale.to_string(), |(_, l)| l[0].to_string()),
+            LanguageTagging::IETF => ietf_language_codes()
+                .iter()
+                .find(|(_, l)| l.contains(locale))
+                .map_or(locale.to_string(), |(tag, _)| tag.to_string()),
+        }
+    }
+}
+
+pub fn resolve_locales(locales: &[Locale]) -> Vec<Locale> {
+    let ietf_language_codes = ietf_language_codes();
+    let all_locales = Locale::all();
+
+    let mut resolved = vec![];
+    for locale in locales {
+        if all_locales.contains(locale) {
+            resolved.push(locale.clone())
+        } else if let Some((_, resolved_locales)) = ietf_language_codes
+            .iter()
+            .find(|(tag, _)| tag == &locale.to_string().as_str())
+        {
+            let (first, alternatives) = resolved_locales.split_first().unwrap();
+
+            resolved.push(first.clone());
+            // ignoring `Locale::en_IN` because I think the majority of users which want english
+            // audio / subs want the "actual" english version and not the hindi accent dub
+            if !alternatives.is_empty() && resolved_locales.first().unwrap() != &Locale::en_IN {
+                warn!("Resolving locale '{}' to '{}', but there are some alternatives: {}. If you an alternative instead, please write it completely out instead of '{}'", locale, first, alternatives.iter().map(|l| format!("'{l}'")).collect::<Vec<String>>().join(", "), locale)
+            }
+        } else {
+            resolved.push(locale.clone());
+            warn!("Unknown locale '{}'", locale)
+        }
+    }
+
+    resolved
+}
+
+fn ietf_language_codes<'a>() -> Vec<(&'a str, Vec<Locale>)> {
+    vec![
+        ("ar", vec![Locale::ar_ME, Locale::ar_SA]),
+        ("ca", vec![Locale::ca_ES]),
+        ("de", vec![Locale::de_DE]),
+        ("en", vec![Locale::en_US, Locale::hi_IN]),
+        ("es", vec![Locale::es_ES, Locale::es_419, Locale::es_LA]),
+        ("fr", vec![Locale::fr_FR]),
+        ("hi", vec![Locale::hi_IN]),
+        ("id", vec![Locale::id_ID]),
+        ("it", vec![Locale::it_IT]),
+        ("ja", vec![Locale::ja_JP]),
+        ("ko", vec![Locale::ko_KR]),
+        ("ms", vec![Locale::ms_MY]),
+        ("pl", vec![Locale::pl_PL]),
+        ("pt", vec![Locale::pt_PT, Locale::pt_BR]),
+        ("ru", vec![Locale::ru_RU]),
+        ("ta", vec![Locale::ta_IN]),
+        ("te", vec![Locale::te_IN]),
+        ("th", vec![Locale::th_TH]),
+        ("tr", vec![Locale::tr_TR]),
+        ("vi", vec![Locale::vi_VN]),
+        ("zh", vec![Locale::zh_CN, Locale::zh_HK, Locale::zh_TW]),
+    ]
+}
 
 /// Return the locale of the system.
 pub fn system_locale() -> Locale {