Initial commit

brittle-core/src/bibtex/validation.rs

@@ -0,0 +1,104 @@
+use crate::error::BibtexError;
+use crate::model::{EntryType, Reference};
+
+/// Returns the required fields for a given BibTeX entry type.
+fn required_fields(entry_type: &EntryType) -> &'static [&'static str] {
+    match entry_type {
+        EntryType::Article => &["author", "title", "journal", "year"],
+        EntryType::Book => &["title", "publisher", "year"],
+        EntryType::Booklet => &["title"],
+        EntryType::InBook => &["title", "publisher", "year", "chapter"],
+        EntryType::InCollection => &["author", "title", "booktitle", "publisher", "year"],
+        EntryType::InProceedings => &["author", "title", "booktitle", "year"],
+        EntryType::Manual => &["title"],
+        EntryType::MastersThesis => &["author", "title", "school", "year"],
+        EntryType::Misc => &[],
+        EntryType::PhdThesis => &["author", "title", "school", "year"],
+        EntryType::Proceedings => &["title", "year"],
+        EntryType::TechReport => &["author", "title", "institution", "year"],
+        EntryType::Unpublished => &["author", "title", "note"],
+        EntryType::Online => &["title", "url"],
+    }
+}
+
+/// Validate that a reference has all required fields for BibTeX export.
+/// Returns an error describing the first missing required field found.
+pub fn validate_for_export(reference: &Reference) -> Result<(), BibtexError> {
+    let required = required_fields(&reference.entry_type);
+
+    for &field in required {
+        let present = match field {
+            "author" => !reference.authors.is_empty(),
+            "editor" => !reference.editors.is_empty(),
+            _ => reference.fields.contains_key(field),
+        };
+        if !present {
+            return Err(BibtexError::MissingRequiredField {
+                cite_key: reference.cite_key.clone(),
+                entry_type: reference.entry_type.bibtex_name().to_owned(),
+                field: field.to_owned(),
+            });
+        }
+    }
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::model::{EntryType, Person, Reference};
+
+    fn make_article() -> Reference {
+        let mut r = Reference::new("doe2024", EntryType::Article);
+        r.authors.push(Person::new("Doe"));
+        r.fields.insert("title".into(), "A Paper".into());
+        r.fields.insert("journal".into(), "Nature".into());
+        r.fields.insert("year".into(), "2024".into());
+        r
+    }
+
+    #[test]
+    fn valid_article_passes() {
+        let r = make_article();
+        assert!(validate_for_export(&r).is_ok());
+    }
+
+    #[test]
+    fn article_missing_author_fails() {
+        let mut r = make_article();
+        r.authors.clear();
+        let err = validate_for_export(&r).unwrap_err();
+        assert!(
+            matches!(err, BibtexError::MissingRequiredField { field, .. } if field == "author")
+        );
+    }
+
+    #[test]
+    fn article_missing_journal_fails() {
+        let mut r = make_article();
+        r.fields.remove("journal");
+        let err = validate_for_export(&r).unwrap_err();
+        assert!(
+            matches!(err, BibtexError::MissingRequiredField { field, .. } if field == "journal")
+        );
+    }
+
+    #[test]
+    fn misc_has_no_required_fields() {
+        let r = Reference::new("anon", EntryType::Misc);
+        assert!(validate_for_export(&r).is_ok());
+    }
+
+    #[test]
+    fn phd_thesis_requires_school() {
+        let mut r = Reference::new("smith2020", EntryType::PhdThesis);
+        r.authors.push(Person::new("Smith"));
+        r.fields.insert("title".into(), "A Thesis".into());
+        r.fields.insert("year".into(), "2020".into());
+        let err = validate_for_export(&r).unwrap_err();
+        assert!(
+            matches!(err, BibtexError::MissingRequiredField { field, .. } if field == "school")
+        );
+    }
+}