Fix widget filters, dates, and Colab demo (#64)

Author: nicosuave

examples/widget_demo.ipynb

@@ -99,7 +99,8 @@
     "from sidemantic.widget import MetricsExplorer\n",
     "\n",
     "# Simple mode: just pass data (DuckDB relation)\n",
-    "widget = MetricsExplorer(conn.table(\"auctions\"))\n",
+    "max_cardinality = 50 if \"COLAB_RELEASE_TAG\" in os.environ else None\n",
+    "widget = MetricsExplorer(conn.table(\"auctions\"), max_dimension_cardinality=max_cardinality)\n",
     "widget"
    ]
   },

js/widget.js

@@ -12,11 +12,30 @@ import { tableFromIPC } from "apache-arrow";
 // ============================================================================
 
 function formatNumber(value, format = "number") {
-  if (value == null || !Number.isFinite(value)) return "—";
+  if (value == null) return "—";
+  if (typeof value === "bigint") {
+    return value.toLocaleString("en-US");
+  }
+  if (typeof value === "string") {
+    const trimmed = value.trim();
+    if (/^-?\d+$/.test(trimmed)) {
+      try {
+        return BigInt(trimmed).toLocaleString("en-US");
+      } catch {}
+    }
+    const parsed = Number(trimmed);
+    if (!Number.isFinite(parsed)) return "—";
+    if (format === "currency") {
+      return `$${parsed.toFixed(2)}`;
+    }
+    return parsed.toLocaleString();
+  }
+  const numericValue = Number(value);
+  if (!Number.isFinite(numericValue)) return "—";
   if (format === "currency") {
-    return `$${Number(value).toFixed(2)}`;
+    return `$${numericValue.toFixed(2)}`;
   }
-  return Number(value).toLocaleString();
+  return numericValue.toLocaleString();
 }
 
 function formatDate(date) {

sidemantic/widget/_widget.py

@@ -16,11 +16,34 @@
     from sidemantic.sql.generator import SQLGenerator
 
 
-def _table_to_ipc(table) -> str:
-    """Serialize Arrow table to IPC format (base64 for widget transport)."""
+def _table_to_ipc(table, *, decimal_mode: str = "float") -> str:
+    """Serialize Arrow table to IPC format (base64 for widget transport).
+
+    Args:
+        table: PyArrow table
+        decimal_mode: "float" to cast decimals to float64, "string" to preserve precision as strings
+    """
     import base64
 
     import pyarrow as pa
+    import pyarrow.compute as pc
+
+    if any(pa.types.is_decimal(field.type) for field in table.schema):
+        arrays = []
+        fields = []
+        for field in table.schema:
+            column = table[field.name]
+            if pa.types.is_decimal(field.type):
+                if decimal_mode == "string":
+                    cast_type = pa.string()
+                else:
+                    cast_type = pa.float64()
+                arrays.append(pc.cast(column, cast_type))
+                fields.append(pa.field(field.name, cast_type))
+            else:
+                arrays.append(column)
+                fields.append(field)
+        table = pa.table(arrays, schema=pa.schema(fields))
 
     sink = io.BytesIO()
     with pa.ipc.new_file(sink, table.schema) as writer:
@@ -590,7 +613,7 @@ def _refresh_metrics(self, *, sync_status: bool = True):
                 skip_default_time_dimensions=True,
             )
             result = self._conn.execute(sql).arrow()
-            self.metric_series_data = _table_to_ipc(result)
+            self.metric_series_data = _table_to_ipc(result, decimal_mode="float")
 
             totals_sql = self._generator.generate(
                 metrics=metric_refs,
@@ -603,7 +626,15 @@ def _refresh_metrics(self, *, sync_status: bool = True):
             totals = {}
             if totals_row:
                 for i, metric_ref in enumerate(metric_refs):
-                    totals[metric_ref.split(".")[-1]] = totals_row[i]
+                    value = totals_row[i]
+                    try:
+                        from decimal import Decimal
+
+                        if isinstance(value, Decimal):
+                            value = str(value)
+                    except Exception:
+                        pass
+                    totals[metric_ref.split(".")[-1]] = value
             self.metric_totals = totals
             self._record_query_intent(metric_refs, [time_dim_ref], grain)
         except Exception as e:
@@ -646,7 +677,7 @@ def _refresh_dimensions(self, *, sync_status: bool = True):
                     use_preaggregations=self._use_preaggregations,
                 )
                 result = self._conn.execute(sql).arrow()
-                dimension_data[dim_key] = _table_to_ipc(result)
+                dimension_data[dim_key] = _table_to_ipc(result, decimal_mode="string")
                 self.dimension_data = dict(dimension_data)
                 self._record_query_intent([selected_metric_ref], [dim_ref], self.time_grain or "day")
             except Exception as e:
@@ -680,7 +711,7 @@ def _refresh_dimensions(self, *, sync_status: bool = True):
                     use_preaggregations=self._use_preaggregations,
                 )
                 result = self._conn.execute(sql).arrow()
-                dimension_data[dim_key] = _table_to_ipc(result)
+                dimension_data[dim_key] = _table_to_ipc(result, decimal_mode="string")
                 self.dimension_data = dict(dimension_data)
                 self._record_query_intent([selected_metric_ref], [dim_ref], self.time_grain or "day")
             except Exception as e: