fixed nested filtering syntax

src/queryer/mod.rs

@@ -54,6 +54,45 @@ impl Queryer {
     self.execute_sql(schema_id, &sql, &args)
   }
 
+  fn extract_filters(
+    prefix: String,
+    val: &serde_json::Value,
+    entries: &mut Vec<(String, serde_json::Value)>,
+  ) -> Result<(), String> {
+    if let Some(obj) = val.as_object() {
+      let mut is_op_obj = false;
+      if let Some(first_key) = obj.keys().next() {
+        if first_key.starts_with('$') {
+          is_op_obj = true;
+        }
+      }
+
+      if is_op_obj {
+        for (op, op_val) in obj {
+          if !op.starts_with('$') {
+            return Err(format!("Filter operator must start with '$', got: {}", op));
+          }
+          entries.push((format!("{}:{}", prefix, op), op_val.clone()));
+        }
+      } else {
+        for (k, v) in obj {
+          let next_prefix = if prefix.is_empty() {
+            k.clone()
+          } else {
+            format!("{}/{}", prefix, k)
+          };
+          Self::extract_filters(next_prefix, v, entries)?;
+        }
+      }
+    } else {
+      return Err(format!(
+        "Filter for path '{}' must be an operator object like {{$eq: ...}} or a nested map.",
+        prefix
+      ));
+    }
+    Ok(())
+  }
+
   fn parse_filter_entries(
     &self,
     filters_map: Option<&serde_json::Map<String, serde_json::Value>>,
@@ -61,19 +100,7 @@ impl Queryer {
     let mut filter_entries: Vec<(String, serde_json::Value)> = Vec::new();
     if let Some(fm) = filters_map {
       for (key, val) in fm {
-        if let Some(obj) = val.as_object() {
-          for (op, op_val) in obj {
-            if !op.starts_with('$') {
-              return Err(format!("Filter operator must start with '$', got: {}", op));
-            }
-            filter_entries.push((format!("{}:{}", key, op), op_val.clone()));
-          }
-        } else {
-          return Err(format!(
-            "Filter for field '{}' must be an object with operators like $eq, $in, etc.",
-            key
-          ));
-        }
+        Self::extract_filters(key.clone(), val, &mut filter_entries)?;
       }
     }
     filter_entries.sort_by(|a, b| a.0.cmp(&b.0));