feat(sql): run the statement at the cursor, splitter with offsets (#1148)

lib/core/database/destructive_sql_detector.dart

@@ -1,3 +1,5 @@
+import 'package:querya_desktop/core/database/sql_statement_splitter.dart';
+
 /// Categorization of destructive SQL / Mongo / Redis operations that can
 /// alter or destroy schema/data.
 enum DestructiveSqlType {
@@ -287,107 +289,9 @@ abstract final class DestructiveSqlDetector {
 
   /// Splits an SQL query into individual statements on `;`, taking into account
   /// comments and string literals.
-  static List<String> splitStatements(String sql) {
-    final statements = <String>[];
-    final current = StringBuffer();
-    final len = sql.length;
-    var i = 0;
-
-    while (i < len) {
-      // Line comment
-      if (i + 1 < len && sql[i] == '-' && sql[i + 1] == '-') {
-        while (i < len && sql[i] != '\n' && sql[i] != '\r') {
-          current.write(sql[i]);
-          i++;
-        }
-        continue;
-      }
-
-      // Block comment
-      if (i + 1 < len && sql[i] == '/' && sql[i + 1] == '*') {
-        current.write('/*');
-        i += 2;
-        while (i + 1 < len && !(sql[i] == '*' && sql[i + 1] == '/')) {
-          current.write(sql[i]);
-          i++;
-        }
-        if (i + 1 < len) {
-          current.write('*/');
-          i += 2;
-        } else {
-          i = len;
-        }
-        continue;
-      }
-
-      // Dollar quotes
-      if (sql[i] == '\$') {
-        final match =
-            RegExp(r'^\$([a-zA-Z0-9_]*)\$').matchAsPrefix(sql.substring(i));
-        if (match != null) {
-          final tag = match.group(0)!;
-          current.write(tag);
-          i += tag.length;
-          final closeIdx = sql.indexOf(tag, i);
-          if (closeIdx != -1) {
-            current.write(sql.substring(i, closeIdx + tag.length));
-            i = closeIdx + tag.length;
-          } else {
-            current.write(sql.substring(i));
-            i = len;
-          }
-          continue;
-        }
-      }
-
-      // String literal
-      if (sql[i] == "'") {
-        current.write("'");
-        i++;
-        while (i < len) {
-          if (sql[i] == "'") {
-            current.write("'");
-            if (i + 1 < len && sql[i + 1] == "'") {
-              current.write("'");
-              i += 2;
-            } else {
-              i++;
-              break;
-            }
-          } else if (sql[i] == '\\' && i + 1 < len) {
-            current.write(sql[i]);
-            current.write(sql[i + 1]);
-            i += 2;
-          } else {
-            current.write(sql[i]);
-            i++;
-          }
-        }
-        continue;
-      }
-
-      // Statement delimiter
-      if (sql[i] == ';') {
-        final stmt = current.toString().trim();
-        if (stmt.isNotEmpty) {
-          statements.add(stmt);
-        }
-        current.clear();
-        i++;
-        continue;
-      }
-
-      current.write(sql[i]);
-      i++;
-    }
-
-    final remaining = current.toString().trim();
-    if (remaining.isNotEmpty) {
-      statements.add(remaining);
-    }
-
-    return statements;
-  }
+  static List<String> splitStatements(String sql) => [
+        for (final span in SqlStatementSplitter.spans(sql)) span.textIn(sql),
+      ];
 
   /// Inspects [sql] and returns any detected destructive operations.
   static DestructiveSqlInspectionResult inspect(String sql) {

lib/core/database/sql_statement_splitter.dart

@@ -0,0 +1,154 @@
+/// One statement of a script, as offsets into the script.
+class SqlStatementSpan {
+  const SqlStatementSpan({
+    required this.start,
+    required this.end,
+    required this.line,
+  });
+
+  /// Offset of the first character of the statement (leading blanks skipped).
+  final int start;
+
+  /// Offset after its last character (trailing blanks and the `;` excluded).
+  final int end;
+
+  /// 1-based line of [start].
+  final int line;
+
+  String textIn(String sql) => sql.substring(start, end);
+}
+
+/// Splits SQL scripts into statement ranges. Semicolons inside string
+/// literals, quoted identifiers, comments and PostgreSQL dollar quotes do not
+/// end a statement.
+abstract final class SqlStatementSplitter {
+  static List<SqlStatementSpan> spans(String sql) {
+    final out = <SqlStatementSpan>[];
+    final len = sql.length;
+    var i = 0;
+    var segmentStart = 0;
+
+    void close(int end) {
+      var s = segmentStart;
+      var e = end;
+      while (s < e && _isBlank(sql.codeUnitAt(s))) {
+        s++;
+      }
+      while (e > s && _isBlank(sql.codeUnitAt(e - 1))) {
+        e--;
+      }
+      if (e > s) {
+        out.add(SqlStatementSpan(start: s, end: e, line: _lineOf(sql, s)));
+      }
+    }
+
+    while (i < len) {
+      final c = sql[i];
+
+      // Line comment: runs to the end of the line.
+      if (c == '-' && i + 1 < len && sql[i + 1] == '-') {
+        while (i < len && sql[i] != '\n' && sql[i] != '\r') {
+          i++;
+        }
+        continue;
+      }
+
+      // Block comment.
+      if (c == '/' && i + 1 < len && sql[i + 1] == '*') {
+        i += 2;
+        while (i + 1 < len && !(sql[i] == '*' && sql[i + 1] == '/')) {
+          i++;
+        }
+        i = i + 1 < len ? i + 2 : len;
+        continue;
+      }
+
+      // Dollar quote: $tag$ ... $tag$.
+      if (c == '\$') {
+        final match =
+            RegExp(r'^\$([a-zA-Z0-9_]*)\$').matchAsPrefix(sql.substring(i));
+        if (match != null) {
+          final tag = match.group(0)!;
+          final close = sql.indexOf(tag, i + tag.length);
+          i = close == -1 ? len : close + tag.length;
+          continue;
+        }
+      }
+
+      // String literal, with doubled quotes and backslash escapes.
+      if (c == "'") {
+        i++;
+        while (i < len) {
+          if (sql[i] == "'") {
+            if (i + 1 < len && sql[i + 1] == "'") {
+              i += 2;
+            } else {
+              i++;
+              break;
+            }
+          } else if (sql[i] == '\\' && i + 1 < len) {
+            i += 2;
+          } else {
+            i++;
+          }
+        }
+        continue;
+      }
+
+      // Quoted identifier: "name" (PostgreSQL) or `name` (MySQL).
+      if (c == '"' || c == '`') {
+        i++;
+        while (i < len) {
+          if (sql[i] == c) {
+            if (i + 1 < len && sql[i + 1] == c) {
+              i += 2;
+            } else {
+              i++;
+              break;
+            }
+          } else {
+            i++;
+          }
+        }
+        continue;
+      }
+
+      if (c == ';') {
+        close(i);
+        i++;
+        segmentStart = i;
+        continue;
+      }
+
+      i++;
+    }
+    close(len);
+    return out;
+  }
+
+  /// The statement the caret at [offset] belongs to. Between statements (a
+  /// blank line, or after the last `;`) it is the statement above; before the
+  /// first statement it is the first one. Null for an empty script.
+  static SqlStatementSpan? at(List<SqlStatementSpan> spans, int offset) {
+    if (spans.isEmpty) return null;
+    for (final s in spans) {
+      if (offset >= s.start && offset <= s.end) return s;
+    }
+    SqlStatementSpan? above;
+    for (final s in spans) {
+      if (s.end <= offset) above = s;
+    }
+    return above ?? spans.first;
+  }
+
+  static bool _isBlank(int c) =>
+      c == 0x20 || c == 0x09 || c == 0x0A || c == 0x0D || c == 0x0B || c == 0x0C;
+
+  static int _lineOf(String sql, int offset) {
+    var line = 1;
+    for (var i = 0; i < offset; i++) {
+      if (sql.codeUnitAt(i) == 0x0A) line++;
+    }
+    return line;
+  }
+}

lib/features/workspace/generic_sql_workspace.dart

@@ -1,3 +1,4 @@
+import 'package:querya_desktop/core/database/sql_statement_splitter.dart';
 import 'dart:async';
 import 'dart:io';
 
@@ -399,16 +400,28 @@ class GenericSqlWorkspaceState extends material.State<GenericSqlWorkspace> {
     }
   }
 
-  Future<void> execute([SqlQueryTabSession? targetSession]) async {
+  /// Runs the selection, else the whole text. With [statementAtCursor] (run
+  /// statement) only the statement under the caret, see [SqlStatementSplitter].
+  Future<void> execute([
+    SqlQueryTabSession? targetSession,
+    bool statementAtCursor = false,
+  ]) async {
     final session = targetSession ?? _activeSession;
     if (session.running) return;
 
     final selection = session.controller.selection;
+    final text = session.controller.text;
     String userSql;
     if (selection.isValid && !selection.isCollapsed) {
-      userSql = selection.textInside(session.controller.text).trim();
+      userSql = selection.textInside(text).trim();
+    } else if (statementAtCursor) {
+      final span = SqlStatementSplitter.at(
+        SqlStatementSplitter.spans(text),
+        selection.isValid ? selection.baseOffset : text.length,
+      );
+      userSql = span == null ? '' : span.textIn(text);
     } else {
-      userSql = session.controller.text.trim();
+      userSql = text.trim();
     }
     if (userSql.isEmpty) return;
 
@@ -861,22 +874,28 @@ class GenericSqlWorkspaceState extends material.State<GenericSqlWorkspace> {
             if (!_activeSession.running) unawaited(execute(_activeSession));
           },
           const material.SingleActivator(LogicalKeyboardKey.enter, control: true): () {
-            if (!_activeSession.running) unawaited(execute(_activeSession));
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
           },
           const material.SingleActivator(LogicalKeyboardKey.enter, meta: true): () {
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
+          },
+          const material.SingleActivator(LogicalKeyboardKey.enter, control: true, shift: true): () {
             if (!_activeSession.running) unawaited(execute(_activeSession));
           },
-          const material.SingleActivator(LogicalKeyboardKey.numpadEnter, control: true): () {
+          const material.SingleActivator(LogicalKeyboardKey.enter, meta: true, shift: true): () {
             if (!_activeSession.running) unawaited(execute(_activeSession));
           },
+          const material.SingleActivator(LogicalKeyboardKey.numpadEnter, control: true): () {
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
+          },
           const material.SingleActivator(LogicalKeyboardKey.numpadEnter, meta: true): () {
-            if (!_activeSession.running) unawaited(execute(_activeSession));
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
           },
           const material.SingleActivator(LogicalKeyboardKey.keyR, control: true): () {
-            if (!_activeSession.running) unawaited(execute(_activeSession));
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
           },
           const material.SingleActivator(LogicalKeyboardKey.keyR, meta: true): () {
-            if (!_activeSession.running) unawaited(execute(_activeSession));
+            if (!_activeSession.running) unawaited(execute(_activeSession, true));
           },
         },
         child: material.Focus(