refactor

backend/src/utils/mod.rs

@@ -4,7 +4,9 @@ pub mod error;
 pub mod http;
 pub mod json;
 pub mod named_entity;
+pub mod setops;
 pub mod storage_paths;
+pub mod text;
 pub mod time;
 pub mod tracing;
 pub mod validation;

backend/src/utils/setops.rs

@@ -0,0 +1,41 @@
+use std::collections::HashSet;
+use std::hash::Hash;
+
+use uuid::Uuid;
+
+use crate::error::AppResult;
+use crate::state::PgPooledConnection;
+
+/// Intersect an optional base set with a new set, returning the resulting option.
+pub fn intersect_option_sets<T>(base: Option<HashSet<T>>, next: HashSet<T>) -> Option<HashSet<T>>
+where
+    T: Eq + Hash + Copy,
+{
+    Some(match base {
+        Some(existing) => existing.intersection(&next).copied().collect(),
+        None => next,
+    })
+}
+
+/// Iteratively intersect documents linked via a join table loader.
+pub fn load_linked_doc_ids<F>(
+    conn: &mut PgPooledConnection,
+    ids: &[Uuid],
+    mut loader: F,
+) -> AppResult<HashSet<Uuid>>
+where
+    F: FnMut(&mut PgPooledConnection, Uuid) -> AppResult<HashSet<Uuid>>,
+{
+    let mut current: Option<HashSet<Uuid>> = None;
+
+    for id in ids {
+        let docs_set = loader(conn, *id)?;
+        current = intersect_option_sets(current, docs_set);
+
+        if current.as_ref().is_some_and(|set| set.is_empty()) {
+            break;
+        }
+    }
+
+    Ok(current.unwrap_or_default())
+}

backend/src/utils/text.rs

@@ -0,0 +1,31 @@
+use crate::error::{AppError, AppResult};
+
+/// Normalizes an identifier-like user input by trimming, enforcing length, and validating characters.
+pub fn normalize_identifier<F>(
+    value: &str,
+    max_len: usize,
+    empty_message: &str,
+    length_message: &str,
+    invalid_message: Option<&str>,
+    mut validator: F,
+) -> AppResult<String>
+where
+    F: FnMut(char) -> bool,
+{
+    let trimmed = value.trim();
+    if trimmed.is_empty() {
+        return Err(AppError::bad_request(empty_message));
+    }
+
+    if trimmed.len() > max_len {
+        return Err(AppError::bad_request(length_message));
+    }
+
+    if let Some(msg) = invalid_message {
+        if !trimmed.chars().all(|ch| validator(ch)) {
+            return Err(AppError::bad_request(msg));
+        }
+    }
+
+    Ok(trimmed.to_string())
+}