refactor: move query parameter extraction function out of flask app

server/utils.py

@@ -0,0 +1,50 @@
+import datetime
+from flask import request
+
+def parse_datetime_filter(value):
+    if not value:
+        return None
+
+    try:
+        return datetime.datetime.fromisoformat(value)
+    except ValueError:
+        try:
+            return datetime.datetime.fromtimestamp(float(value))
+        except ValueError as err:
+            raise ValueError(
+                "Date filters must be ISO-8601 strings or Unix timestamps"
+            ) from err
+
+
+def get_request_filters() -> dict:
+    filters = {}
+
+    search_query = request.args.get("search_query") or request.args.get("query")
+    if search_query:
+        filters["search_query"] = search_query
+
+    start_date = parse_datetime_filter(
+        request.args.get("start_date") or request.args.get("start")
+    )
+    if start_date:
+        filters["start_date"] = start_date
+
+    end_date = parse_datetime_filter(
+        request.args.get("end_date") or request.args.get("end")
+    )
+    if end_date:
+        filters["end_date"] = end_date
+
+    data_sources = request.args.getlist("data_sources")
+    if not data_sources:
+        data_sources = request.args.getlist("sources")
+
+    if len(data_sources) == 1 and "," in data_sources[0]:
+        data_sources = [
+            source.strip() for source in data_sources[0].split(",") if source.strip()
+        ]
+
+    if data_sources:
+        filters["data_sources"] = data_sources
+
+    return filters