1 files changed, 58 insertions, 0 deletions
diff --git a/src/data/delimitedstringvalidator.cpp b/src/data/delimitedstringvalidator.cpp
new file mode 100644
index 0000000..9f1057e
--- /dev/null
+++ b/src/data/delimitedstringvalidator.cpp
@@ -0,0 +1,58 @@
+/*
+    TikZiT - a GUI diagram editor for TikZ
+    Copyright (C) 2018 Aleks Kissinger
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include "delimitedstringvalidator.h"
+
+DelimitedStringValidator::DelimitedStringValidator(QObject *parent) : QValidator(parent)
+{
+}
+
+QValidator::State DelimitedStringValidator::validate(QString &input, int &/*pos*/) const
+{
+    int depth = braceDepth(input);
+    if (depth == 0) return Acceptable;
+    else if (depth > 0) return Intermediate;
+    else return Invalid;
+}
+
+void DelimitedStringValidator::fixup(QString &input) const
+{
+    int depth = braceDepth(input);
+    if (depth > 0) input.append(QString("}").repeated(depth));
+}
+
+int DelimitedStringValidator::braceDepth(QString input) const
+{
+    int depth = 0;
+    bool escape = false;
+    for (int i = 0; i < input.length(); ++i) {
+        QCharRef c = input[i];
+        if (escape) {
+            escape = false;
+        } else if (c == '\\') {
+            escape = true;
+        } else if (c == '{') {
+            depth++;
+        } else if (c == '}') {
+            depth--;
+            if (depth < 0) return -1;
+        }
+    }
+
+    return depth;
+}