vibes

server-rs/src/data/poi.rs

@@ -18,7 +18,12 @@ pub struct POICategoryGroup {
 }
 
 pub struct POIData {
-    pub id: Vec<String>,
+    /// Contiguous buffer holding all POI ID strings end-to-end.
+    id_buffer: String,
+    /// Byte offset into `id_buffer` where each row's ID starts.
+    id_offsets: Vec<u32>,
+    /// Length in bytes of each row's ID.
+    id_lengths: Vec<u8>,
     pub group: InternedColumn,
     pub category: InternedColumn,
     pub name: Vec<String>,
@@ -31,6 +36,15 @@ pub struct POIData {
     pub priority: Vec<u32>,
 }
 
+impl POIData {
+    /// Get the ID string for a given row.
+    pub fn id(&self, row: usize) -> &str {
+        let offset = self.id_offsets[row] as usize;
+        let length = self.id_lengths[row] as usize;
+        &self.id_buffer[offset..offset + length]
+    }
+}
+
 fn extract_str_col(df: &DataFrame, name: &str) -> anyhow::Result<Vec<String>> {
     let column = df
         .column(name)
@@ -72,7 +86,7 @@ impl POIData {
         let row_count = df.height();
         info!("Loaded {} POIs", row_count);
 
-        let id: Vec<String> = extract_str_col(&df, "id")?;
+        let id_raw: Vec<String> = extract_str_col(&df, "id")?;
         let name = extract_str_col(&df, "name")?;
         let category_raw = extract_str_col(&df, "category")?;
         let group_raw = extract_str_col(&df, "group")?;
@@ -80,6 +94,19 @@ impl POIData {
         let lng = extract_f32_col(&df, "lng", 0.0)?;
         let emoji_raw = extract_str_col(&df, "emoji")?;
 
+        // Pack POI IDs into a contiguous buffer
+        let total_id_bytes: usize = id_raw.iter().map(|s| s.len()).sum();
+        let mut id_buffer = String::with_capacity(total_id_bytes);
+        let mut id_offsets = Vec::with_capacity(row_count);
+        let mut id_lengths = Vec::with_capacity(row_count);
+        for s in &id_raw {
+            let offset = id_buffer.len() as u32;
+            let length = s.len().min(u8::MAX as usize) as u8;
+            id_offsets.push(offset);
+            id_lengths.push(length);
+            id_buffer.push_str(&s[..length as usize]);
+        }
+
         let category = InternedColumn::build(&category_raw);
         let group = InternedColumn::build(&group_raw);
         let emoji = InternedColumn::build(&emoji_raw);
@@ -99,7 +126,9 @@ impl POIData {
         info!("POI data loading complete.");
 
         Ok(POIData {
-            id,
+            id_buffer,
+            id_offsets,
+            id_lengths,
             name,
             category,
             group,