feat(sql-workspace): caret at the error position, one error panel for SQL and Mongo (#1557)

lib/core/database/query_error_text.dart

@@ -1,3 +1,7 @@
+import 'dart:convert';
+
+import 'package:postgres/postgres.dart' show ServerException;
+
 /// A failed query as the results pane shows it (#1557): one readable line,
 /// and the driver's text without the statement the app wrapped around the
 /// user's SQL.
@@ -69,4 +73,41 @@ class QueryErrorText {
 
   static String _cap(String s) =>
       s.length <= _maxSummary ? s : '${s.substring(0, _maxSummary)}…';
+
+  /// `SELECT * FROM (\n` the wrapper puts before the user's SQL.
+  static const _wrapperPrefix = 'SELECT * FROM (\n';
+
+  // SQLite: `Causing statement (at position 29): ...`, a byte offset into the
+  // statement the driver prepared.
+  static final _sqlitePosition = RegExp(r'\(at position (\d+)\)');
+
+  /// Where in [sql], the text that was sent, the error is: a 0-based offset in
+  /// characters, or null when the driver does not say (MySQL) or the place is
+  /// not in [sql].
+  ///
+  /// PostgreSQL gives a 1-based character position in the statement; SQLite a
+  /// byte offset in the statement it prepared, which is the user's SQL inside
+  /// the app's wrapper when [sql] is a query (#1144), so the wrapper's prefix
+  /// is taken off. The row limit the app appends comes after the text, so it
+  /// does not move anything.
+  static int? offsetIn(Object error, String sql) {
+    if (error is ServerException) return offsetOfPgPosition(error.position, sql);
+    final text = error.toString();
+    final m = _sqlitePosition.firstMatch(text);
+    if (m == null) return null;
+    var bytes = int.parse(m[1]!);
+    if (text.contains(_wrapperPrefix)) bytes -= _wrapperPrefix.length;
+    if (bytes < 0) return null;
+    final encoded = utf8.encode(sql);
+    if (bytes > encoded.length) return null;
+    return utf8.decode(encoded.sublist(0, bytes), allowMalformed: true).length;
+  }
+
+  /// The offset in [sql] of a PostgreSQL `position` (1-based, in characters),
+  /// or null when there is none or it lies outside [sql].
+  static int? offsetOfPgPosition(int? position, String sql) {
+    if (position == null) return null;
+    final offset = position - 1;
+    return offset >= 0 && offset <= sql.length ? offset : null;
+  }
 }

lib/features/mongodb/mongo_query_workspace.dart

@@ -11,6 +11,8 @@ import 'package:querya_desktop/features/mongodb/mongo_documents_json_view.dart';
 import 'package:querya_desktop/features/mongodb/mongo_documents_table_view.dart';
 import 'package:querya_desktop/features/mongodb/mongo_query_executor.dart';
 import 'package:querya_desktop/features/mongodb/mql_parser.dart';
+import 'package:querya_desktop/core/database/query_error_text.dart';
+import 'package:querya_desktop/shared/widgets/query_error_view.dart';
 import 'package:querya_desktop/shared/widgets/widgets.dart';
 import 'package:querya_desktop/core/ui/querya_control_tokens.dart';
 
@@ -499,15 +501,7 @@ class _MongoQueryWorkspaceState extends material.State<MongoQueryWorkspace> {
               ],
             ),
             const Gap(8),
-            material.SelectableText(
-              tab.error!,
-              style: material.TextStyle(
-                color: cs.destructive,
-                fontFamily: QueryaTypography.mono,
-                fontFamilyFallback: QueryaTypography.monoFontFamilyFallback,
-                fontSize: 12.5,
-              ),
-            ),
+            QueryErrorView(error: QueryErrorText.parse(tab.error!), inline: true),
           ],
         ),
       );

lib/features/workspace/generic_sql_workspace.dart

@@ -1,4 +1,5 @@
 import 'package:querya_desktop/core/erd/erd_saved_layout.dart';
+import 'package:querya_desktop/core/database/query_error_text.dart';
 import 'package:querya_desktop/core/database/statement_queue.dart';
 import 'package:querya_desktop/core/database/sql_statement_splitter.dart';
 import 'dart:async';
@@ -810,6 +811,20 @@ class GenericSqlWorkspaceState extends material.State<GenericSqlWorkspace> {
     } catch (e) {
       if (mounted) {
         invalidatePane(session);
+        // One statement: the caret goes where the driver says it failed.
+        if (sent.length == 1) {
+          final offset = QueryErrorText.offsetIn(e, sent.single);
+          if (offset != null) {
+            final runStart = statementAtCursor
+                ? scopeStart + spans.single.start
+                : scopeStart + (scope.length - scope.trimLeft().length);
+            // The text may have been edited while the query ran.
+            final at = (runStart + offset)
+                .clamp(0, session.controller.text.length);
+            session.controller.selection =
+                material.TextSelection.collapsed(offset: at);
+          }
+        }
         setState(() {
           session.error = e.toString();
           session.running = false;

lib/features/workspace/results_tab.dart

@@ -5,7 +5,6 @@ import 'package:flutter/services.dart';
 import 'package:querya_desktop/core/security/pii_masking_controller.dart';
 import 'package:querya_desktop/core/actions/data_grid_command_bridge.dart';
 import 'package:querya_desktop/core/database/query_error_text.dart';
-import 'package:querya_desktop/core/widgets/virtual_selectable_text_view.dart';
 import 'package:querya_desktop/features/results/charts/quick_chart_view.dart';
 import 'package:querya_desktop/features/workspace/data_grid_calc_bar.dart';
 import 'package:querya_desktop/features/workspace/data_grid_filter_bar.dart';
@@ -17,6 +16,7 @@ import 'package:querya_desktop/features/workspace/grid_filter_engine.dart';
 import 'package:querya_desktop/features/workspace/grid_selection_calc_engine.dart';
 import 'package:querya_desktop/features/workspace/result_grid_view.dart';
 import 'package:querya_desktop/shared/services/data_export_service.dart';
+import 'package:querya_desktop/shared/widgets/query_error_view.dart';
 import 'package:querya_desktop/shared/widgets/widgets.dart';
 import 'package:querya_desktop/core/ui/querya_control_tokens.dart';
 
@@ -86,8 +86,6 @@ class ResultsTab extends material.StatefulWidget {
 
 class _ResultsTabState extends material.State<ResultsTab> {
   /// The driver text of a query error is folded away until asked for (#1557).
-  bool _showErrorDetails = false;
-  bool _errorCopied = false;
 
   /// Selection / focus state lives in notifiers so a navigation step rebuilds
   /// only the widgets that show it (toolbar, value panel, calc bar), not the
@@ -254,10 +252,6 @@ class _ResultsTabState extends material.State<ResultsTab> {
 
   @override
   void didUpdateWidget(covariant ResultsTab oldWidget) {
-    if (oldWidget.errorMessage != widget.errorMessage) {
-      _showErrorDetails = false;
-      _errorCopied = false;
-    }
     super.didUpdateWidget(oldWidget);
     _syncGridBridge();
     if (!identical(oldWidget.rows, widget.rows) ||
@@ -388,93 +382,6 @@ class _ResultsTabState extends material.State<ResultsTab> {
     super.dispose();
   }
 
-  /// The driver's message as the headline, the rest (without the app's own
-  /// statement wrapping) behind "Show details", and a Copy button (#1557).
-  material.Widget _buildError(
-    material.BuildContext context,
-    QueryErrorText error,
-  ) {
-    final cs = Theme.of(context).colorScheme;
-    return material.Center(
-      key: const material.ValueKey('results_mode_error'),
-      child: material.Padding(
-        padding: const material.EdgeInsets.all(32),
-        child: material.Column(
-          mainAxisAlignment: material.MainAxisAlignment.center,
-          mainAxisSize: material.MainAxisSize.min,
-          children: [
-            material.Icon(
-              material.Icons.error_outline_rounded,
-              size: 48,
-              color: cs.destructive,
-            ),
-            const Gap(16),
-            const Text('Query Error').large().semiBold(),
-            const Gap(8),
-            material.SelectableText(
-              error.summary,
-              textAlign: material.TextAlign.center,
-              style: material.TextStyle(color: cs.foreground, fontSize: 14),
-            ),
-            if (error.hasDetail) ...[
-              const Gap(12),
-              material.Row(
-                mainAxisSize: material.MainAxisSize.min,
-                children: [
-                  QueryaButton.ghost(
-                    label: _showErrorDetails ? 'Hide details' : 'Show details',
-                    icon: _showErrorDetails
-                        ? material.Icons.expand_less_rounded
-                        : material.Icons.expand_more_rounded,
-                    size: QueryaControlSize.sm,
-                    onPressed: () => setState(
-                      () => _showErrorDetails = !_showErrorDetails,
-                    ),
-                  ),
-                  const Gap(6),
-                  QueryaButton.ghost(
-                    label: _errorCopied ? 'Copied' : 'Copy error',
-                    icon: _errorCopied
-                        ? material.Icons.check_rounded
-                        : material.Icons.copy_rounded,
-                    size: QueryaControlSize.sm,
-                    onPressed: () => unawaited(_copyError(error.detail)),
-                  ),
-                ],
-              ),
-            ],
-            if (error.hasDetail && _showErrorDetails) ...[
-              const Gap(8),
-              // A long driver message scrolls inside the space left, instead
-              // of pushing the column past the pane.
-              material.Flexible(
-                child: VirtualSelectableTextView(
-                  text: error.detail,
-                  style: material.TextStyle(
-                    color: cs.mutedForeground,
-                    fontSize: 13,
-                  ),
-                ),
-              ),
-            ],
-            if (widget.errorAction != null) ...[
-              const Gap(16),
-              widget.errorAction!,
-            ],
-          ],
-        ),
-      ),
-    );
-  }
-
-  Future<void> _copyError(String text) async {
-    await Clipboard.setData(ClipboardData(text: text));
-    if (!mounted) return;
-    setState(() => _errorCopied = true);
-    await Future<void>.delayed(const Duration(seconds: 2));
-    if (mounted) setState(() => _errorCopied = false);
-  }
-
   @override
   material.Widget build(material.BuildContext context) {
     if (widget.isLoading) {
@@ -488,7 +395,16 @@ class _ResultsTabState extends material.State<ResultsTab> {
     }
 
     if (widget.errorMessage != null) {
-      return _buildError(context, QueryErrorText.parse(widget.errorMessage!));
+      return material.Center(
+        key: const material.ValueKey('results_mode_error'),
+        child: material.Padding(
+          padding: const material.EdgeInsets.all(32),
+          child: QueryErrorView(
+            error: QueryErrorText.parse(widget.errorMessage!),
+            action: widget.errorAction,
+          ),
+        ),
+      );
     }
 
     if (widget.columns.isEmpty && widget.rows.isEmpty && widget.stagingBuffer == null) {

lib/shared/widgets/query_error_view.dart

@@ -0,0 +1,130 @@
+import 'dart:async' show unawaited;
+
+import 'package:flutter/material.dart' as material;
+import 'package:flutter/services.dart';
+import 'package:querya_desktop/core/database/query_error_text.dart';
+import 'package:querya_desktop/core/ui/querya_control_tokens.dart';
+import 'package:querya_desktop/core/widgets/virtual_selectable_text_view.dart';
+import 'package:querya_desktop/shared/widgets/widgets.dart';
+
+/// A failed query: the driver's message as the headline, the rest (without the
+/// statement the app wrapped around the user's SQL) behind "Show details", and
+/// a Copy button (#1557). Shared by the SQL results pane and the Mongo query
+/// workspace.
+///
+/// [inline] is for a panel that has its own title row (a box above results):
+/// left aligned and without the large icon and title.
+class QueryErrorView extends material.StatefulWidget {
+  const QueryErrorView({
+    super.key,
+    required this.error,
+    this.action,
+    this.inline = false,
+  });
+
+  final QueryErrorText error;
+
+  /// Shown under the error, e.g. a way to fix the connection.
+  final material.Widget? action;
+  final bool inline;
+
+  @override
+  material.State<QueryErrorView> createState() => _QueryErrorViewState();
+}
+
+class _QueryErrorViewState extends material.State<QueryErrorView> {
+  bool _showDetails = false;
+  bool _copied = false;
+
+  @override
+  void didUpdateWidget(covariant QueryErrorView oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (oldWidget.error.detail != widget.error.detail) {
+      _showDetails = false;
+      _copied = false;
+    }
+  }
+
+  Future<void> _copy() async {
+    await Clipboard.setData(ClipboardData(text: widget.error.detail));
+    if (!mounted) return;
+    setState(() => _copied = true);
+    await Future<void>.delayed(const Duration(seconds: 2));
+    if (mounted) setState(() => _copied = false);
+  }
+
+  @override
+  material.Widget build(material.BuildContext context) {
+    final cs = Theme.of(context).colorScheme;
+    final error = widget.error;
+    final inline = widget.inline;
+    final align = inline
+        ? material.CrossAxisAlignment.start
+        : material.CrossAxisAlignment.center;
+    return material.Column(
+      mainAxisAlignment: material.MainAxisAlignment.center,
+      mainAxisSize: material.MainAxisSize.min,
+      crossAxisAlignment: align,
+      children: [
+        if (!inline) ...[
+          material.Icon(
+            material.Icons.error_outline_rounded,
+            size: 48,
+            color: cs.destructive,
+          ),
+          const Gap(16),
+          const Text('Query Error').large().semiBold(),
+          const Gap(8),
+        ],
+        material.SelectableText(
+          error.summary,
+          textAlign: inline ? material.TextAlign.start : material.TextAlign.center,
+          style: material.TextStyle(color: cs.foreground, fontSize: 14),
+        ),
+        if (error.hasDetail) ...[
+          const Gap(12),
+          material.Row(
+            mainAxisSize: material.MainAxisSize.min,
+            children: [
+              QueryaButton.ghost(
+                label: _showDetails ? 'Hide details' : 'Show details',
+                icon: _showDetails
+                    ? material.Icons.expand_less_rounded
+                    : material.Icons.expand_more_rounded,
+                size: QueryaControlSize.sm,
+                onPressed: () => setState(() => _showDetails = !_showDetails),
+              ),
+              const Gap(6),
+              QueryaButton.ghost(
+                label: _copied ? 'Copied' : 'Copy error',
+                icon: _copied
+                    ? material.Icons.check_rounded
+                    : material.Icons.copy_rounded,
+                size: QueryaControlSize.sm,
+                onPressed: () => unawaited(_copy()),
+              ),
+            ],
+          ),
+        ],
+        if (error.hasDetail && _showDetails) ...[
+          const Gap(8),
+          // A long driver message scrolls inside the space left, instead of
+          // pushing the column past the pane.
+          material.Flexible(
+            child: VirtualSelectableTextView(
+              text: error.detail,
+              style: material.TextStyle(
+                color: cs.mutedForeground,
+                fontSize: 13,
+              ),
+            ),
+          ),
+        ],
+        if (widget.action != null) ...[
+          const Gap(16),
+          widget.action!,
+        ],
+      ],
+    );
+  }
+}