1 files changed, 59 insertions, 0 deletions
diff --git a/tikzit/src/common/NSString+Tikz.m b/tikzit/src/common/NSString+Tikz.m
new file mode 100644
index 0000000..85a51d3
--- /dev/null
+++ b/tikzit/src/common/NSString+Tikz.m
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2013  Alex Merry <alex.merry@kdemail.net>
+ *
+ * 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 2 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 <http://www.gnu.org/licenses/>.
+ */
+
+#import "NSString+Tikz.h"
+#import "TikzGraphAssembler.h"
+
+@implementation NSString (Tikz)
+
+- (NSString*) tikzEscapedString {
+	static NSCharacterSet *avoid = nil;
+	if (avoid == nil)
+		avoid = [[[NSCharacterSet characterSetWithCharactersInString:@"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ<>-'0123456789. "] invertedSet] retain];
+
+	if ([self rangeOfCharacterFromSet:avoid].length > 0) {
+		return [NSString stringWithFormat:@"{%@}", self];
+	} else {
+		return [[self retain] autorelease];
+	}
+}
+
+- (BOOL) isValidTikz {
+	NSUInteger length = [self length];
+	unsigned int brace_depth = 0;
+	unsigned int escape = 0;
+	for (NSUInteger i = 0; i < length; ++i) {
+		unichar c = [self characterAtIndex:i];
+
+		if (escape) {
+			escape = 0;
+		} else if (c == '\\') {
+			escape = 1;
+		} else if (c == '{') {
+			brace_depth++;
+		} else if (c == '}') {
+			if (brace_depth == 0)
+				return NO;
+			brace_depth--;
+		}
+	}
+	return !escape && brace_depth == 0;
+}
+
+@end
+
+// vi:ft=objc:noet:ts=4:sts=4:sw=4