Factor out IRC formatting parsing

1 files changed, 89 insertions, 0 deletions

diff --git a/format.c b/format.c
new file mode 100644
index 0000000..800388b
--- /dev/null
+++ b/format.c
@@ -0,0 +1,89 @@
+/* Copyright (C) 2018  Curtis McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <wchar.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+#include "chat.h"
+
+void formatReset(struct Format *format) {
+	format->bold = false;
+	format->italic = false;
+	format->underline = false;
+	format->reverse = false;
+	format->fg = -1;
+	format->bg = -1;
+}
+
+static void parseColor(struct Format *format) {
+	size_t len = MIN(wcsspn(format->str, L"0123456789"), 2);
+	if (!len) {
+		format->fg = -1;
+		format->bg = -1;
+		return;
+	}
+	format->fg = 0;
+	for (size_t i = 0; i < len; ++i) {
+		format->fg *= 10;
+		format->fg += format->str[i] - L'0';
+	}
+	if (format->fg > IRCLightGray) format->fg = -1;
+	format->str = &format->str[len];
+
+	len = 0;
+	if (format->str[0] == L',') {
+		len = MIN(wcsspn(&format->str[1], L"0123456789"), 2);
+	}
+	if (!len) return;
+	format->bg = 0;
+	for (size_t i = 0; i < len; ++i) {
+		format->bg *= 10;
+		format->bg += format->str[1 + i] - L'0';
+	}
+	if (format->bg > IRCLightGray) format->bg = -1;
+	format->str = &format->str[1 + len];
+}
+
+static const wchar_t Stops[] = {
+	L' ',
+	IRCBold, IRCColor, IRCReverse, IRCReset, IRCItalic, IRCUnderline,
+	L'\0',
+};
+
+bool formatParse(struct Format *format, const wchar_t *stop) {
+	format->str += format->len;
+	if (!format->str[0]) return false;
+
+	switch (format->str[0]) {
+		break; case IRCBold:      format->str++; format->bold ^= true;
+		break; case IRCItalic:    format->str++; format->italic ^= true;
+		break; case IRCUnderline: format->str++; format->underline ^= true;
+		break; case IRCReverse:   format->str++; format->reverse ^= true;
+		break; case IRCColor:     format->str++; parseColor(format);
+		break; case IRCReset:     format->str++; formatReset(format);
+	}
+
+	if (format->str[0] == L' ') {
+		format->len = 1 + wcscspn(&format->str[1], Stops);
+	} else {
+		format->len = wcscspn(format->str, Stops);
+	}
+	if (stop && stop > format->str && stop < &format->str[format->len]) {
+		format->len = stop - format->str;
+	}
+	return true;
+}