libdeng2: Added EscapeParser

Utility for parsing a text string with ASCII Esc (0x1b) escape
sequences, used for rich text formatting in libdeng2.

doomsday/libdeng2/data.pri

@@ -16,6 +16,7 @@ HEADERS += \
     include/de/Date \
     include/de/DictionaryValue \
     include/de/DotPath \
+    include/de/EscapeParser \
     include/de/FIFO \
     include/de/FixedByteArray \
     include/de/IBlock \
@@ -64,6 +65,7 @@ HEADERS += \
     include/de/data/counted.h \
     include/de/data/date.h \
     include/de/data/dictionaryvalue.h \
+    include/de/data/escapeparser.h \
     include/de/data/fifo.h \
     include/de/data/fixedbytearray.h \
     include/de/data/huffman.h \
@@ -114,6 +116,7 @@ SOURCES += \
     src/data/counted.cpp \
     src/data/date.cpp \
     src/data/dictionaryvalue.cpp \
+    src/data/escapeparser.cpp \
     src/data/fixedbytearray.cpp \
     src/data/huffman.cpp \
     src/data/info.cpp \

doomsday/libdeng2/include/de/EscapeParser

@@ -0,0 +1 @@
+#include "data/escapeparser.h"

doomsday/libdeng2/include/de/data/escapeparser.h

@@ -0,0 +1,72 @@
+/** @file escapeparser.h  Text escape sequence parser.
+ *
+ * @authors Copyright (c) 2013 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * GPL: http://www.gnu.org/licenses/gpl.html
+ *
+ * <small>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</small> 
+ */
+
+#ifndef LIBDENG2_ESCAPEPARSER_H
+#define LIBDENG2_ESCAPEPARSER_H
+
+#include <de/libdeng2.h>
+#include <de/String>
+#include <de/Observers>
+
+namespace de {
+
+/**
+ * Escape sequence parser for text strings.
+ *
+ * @see DENG2_ESC() macro
+ */
+class DENG2_PUBLIC EscapeParser
+{
+public:
+    /**
+     * Called during parsing when a plain text range has been parsed.
+     *
+     * @param range  Range in the original text.
+     */
+    DENG2_DEFINE_AUDIENCE(PlainText, void handlePlainText(Rangei const &range))
+
+    /**
+     * Called during parsing when an escape sequence has been parsed.
+     * Does not include the Esc (0x1b) in the beginning.
+     *
+     * @param range  Range in the original text.
+     */
+    DENG2_DEFINE_AUDIENCE(EscapeSequence, void handleEscapeSequence(Rangei const &range))
+
+public:
+    EscapeParser();
+
+    void parse(String const &textWithEscapes);
+
+    /**
+     * Returns the original string that was parsed.
+     */
+    String originalText() const;
+
+    /**
+     * Returns the plain text string. Available after parsing.
+     */
+    String plainText() const;
+
+private:
+    DENG2_PRIVATE(d)
+};
+
+} // namespace de
+
+#endif // LIBDENG2_ESCAPEPARSER_H

doomsday/libdeng2/src/data/escapeparser.cpp

@@ -0,0 +1,115 @@
+/** @file escapeparser.cpp
+ *
+ * @authors Copyright (c) 2013 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * GPL: http://www.gnu.org/licenses/gpl.html
+ *
+ * <small>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</small> 
+ */
+
+#include "de/EscapeParser"
+
+namespace de {
+
+DENG2_PIMPL_NOREF(EscapeParser)
+{
+    String original;
+    String plain;
+};
+
+EscapeParser::EscapeParser() : d(new Instance)
+{}
+
+void EscapeParser::parse(String const &textWithEscapes)
+{
+    d->original = textWithEscapes;
+    d->plain.clear();
+
+    Rangei range;
+
+    forever
+    {
+        range.end = d->original.indexOf(QChar('\x1b'), range.start);
+        if(range.end >= 0)
+        {
+            // Empty ranges are ignored.
+            if(range.size() > 0)
+            {
+                DENG2_FOR_AUDIENCE(PlainText, i)
+                {
+                    i->handlePlainText(range);
+                }
+
+                // Update the plain text.
+                d->plain += d->original.substr(range);
+            }
+
+            // Check the escape sequences.
+            int escLen = 2;
+            char ch = d->original[range.end + 1].toLatin1();
+            switch(ch)
+            {
+            case '(':
+            case '[':
+            case '{':
+            case '<': {
+                // Find the matching end.
+                int end = d->original.indexOf(ch == '('? ')' : ch == '['? ']' :
+                                              ch == '{'? '}' : '>', range.end + 1);
+                if(end < 0) end = d->original.size() - 1;
+                escLen = end - range.end + 1;
+                break; }
+
+            case 'T':
+                escLen = 3;
+                break;
+
+            default:
+                break;
+            }
+
+            DENG2_FOR_AUDIENCE(EscapeSequence, i)
+            {
+                i->handleEscapeSequence(Rangei(range.end + 1, range.end + escLen));
+            }
+
+            // Advance the scanner.
+            range.start = range.end + escLen;
+        }
+        else
+        {
+            // Final plain text range.
+            range.end = d->original.size();
+            if(range.size() > 0)
+            {
+                DENG2_FOR_AUDIENCE(PlainText, i)
+                {
+                    i->handlePlainText(range);
+                }
+                d->plain += d->original.substr(range);
+            }
+            break;
+        }
+    }
+}
+
+String EscapeParser::originalText() const
+{
+    return d->original;
+}
+
+String EscapeParser::plainText() const
+{
+    return d->plain;
+}
+
+} // namespace de