Basic and scruffy Subrip read support.

5 files changed, 267 insertions, 17 deletions

diff --git a/src/exceptions.h b/src/exceptions.h
index f2f1246..cb49d86 100644
--- a/src/exceptions.h
+++ b/src/exceptions.h
@@ -22,14 +22,12 @@
 
 namespace sub {
 
-/** @class XMLError
- *  @brief An error raised when reading an XML file.
- */
-class XMLError : public std::exception
+class MessageError : public std::exception
 {
 public:
-	XMLError (std::string const & message) : _message (message) {}
-	~XMLError () throw () {}
+	MessageError (std::string const & message)
+		: _message (message) {}
+	~MessageError () throw () {}
 
 	/** @return error message */
 	char const * what () const throw () {
@@ -41,23 +39,37 @@ private:
 	std::string _message;
 };
 
+/** @class XMLError
+ *  @brief An error raised when reading an XML file.
+ */
+class XMLError : public MessageError
+{
+public:
+	XMLError (std::string const & message)
+		: MessageError (message)
+	{}
+};
+
 /** @class STLError
  *  @brief An error raised when reading a binary STL file.
  */
-class STLError : public std::exception
+class STLError : public MessageError
 {
 public:
-	STLError (std::string const & message) : _message (message) {}
-	~STLError () throw () {}
-
-	/** @return error message */
-	char const * what () const throw () {
-		return _message.c_str ();
-	}
+	STLError (std::string const & message)
+		: MessageError (message)
+	{}
+};
 
-private:
-	/** error message */
-	std::string _message;
+/** @class SubripError
+ *  @brief An error raised when reading a Subrip file.
+ */
+class SubripError : public MessageError
+{
+public:
+	SubripError (std::string saw, std::string expecting)
+		: MessageError ("Error in SubRip file: saw " + saw + " while expecting " + expecting)
+	{}
 };
 
 }
diff --git a/src/subrip_reader.cc b/src/subrip_reader.cc
new file mode 100644
index 0000000..873a6f1
--- /dev/null
+++ b/src/subrip_reader.cc
@@ -0,0 +1,191 @@
+/*
+    Copyright (C) 2014 Carl Hetherington <cth@carlh.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, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "subrip_reader.h"
+#include "exceptions.h"
+#include <boost/algorithm/string.hpp>
+#include <boost/lexical_cast.hpp>
+#include <cstdio>
+#include <vector>
+
+using std::string;
+using std::vector;
+using boost::lexical_cast;
+using namespace sub;
+
+SubripReader::SubripReader (FILE* f)
+{
+	enum {
+		COUNTER,
+		METADATA,
+		CONTENT
+	} state = COUNTER;
+
+	char buffer[256];
+
+	TimePair from;
+	TimePair to;
+
+	string line;
+	int line_number = 0;
+
+	while (!feof (f)) {
+		fgets (buffer, sizeof (buffer), f);
+		if (feof (f)) {
+			break;
+		}
+
+		line = string (buffer);
+		trim_right_if (line, boost::is_any_of ("\n\r"));
+
+		switch (state) {
+		case COUNTER:
+		{
+			if (line.empty ()) {
+				/* a blank line at the start is ok */
+				break;
+			}
+
+			state = METADATA;
+		}
+		break;
+		case METADATA:
+		{
+			vector<string> p;
+			boost::algorithm::split (p, line, boost::algorithm::is_any_of (" "));
+			if (p.size() != 3 && p.size() != 7) {
+				throw SubripError (line, "a time/position line");
+			}
+
+			from = convert_time (p[0]);
+			to = convert_time (p[2]);
+
+			/* XXX: should not ignore coordinate specifications */
+			
+			state = CONTENT;
+			break;
+		}
+		case CONTENT:
+			if (line.empty ()) {
+				state = COUNTER;
+				line_number = 0;
+			} else {
+				convert_line (line, line_number, from, to);
+				line_number++;
+			}
+			break;
+		}
+	}
+}
+
+TimePair
+SubripReader::convert_time (string t)
+{
+	vector<string> a;
+	boost::algorithm::split (a, t, boost::is_any_of (":"));
+	if (a.size() != 3) {
+		throw SubripError (t, "time in the format h:m:s,ms");
+	}
+
+	vector<string> b;
+	boost::algorithm::split (b, a[2], boost::is_any_of (","));
+
+	return TimePair (
+		MetricTime (
+			lexical_cast<int> (a[0]),
+			lexical_cast<int> (a[1]),
+			lexical_cast<int> (b[0]),
+			lexical_cast<int> (b[1])
+			)
+		);
+}
+
+void
+SubripReader::convert_line (string t, int line_number, TimePair from, TimePair to)
+{
+	enum {
+		TEXT,
+		TAG
+	} state = TEXT;
+	
+	string tag;
+
+	RawSubtitle p;
+	p.font = "Arial";
+	p.font_size.set_points (48);
+	p.from = from;
+	p.to = to;
+	p.vertical_position.proportional = 0.7 + line_number * 0.1;
+	p.vertical_position.reference = TOP;
+	
+	/* XXX: missing <font> support */
+	/* XXX: nesting of tags e.g. <b>foo<i>bar<b>baz</b>fred</i>jim</b> might
+	   not work, I think.
+	*/
+
+	for (size_t i = 0; i < t.size(); ++i) {
+		switch (state) {
+		case TEXT:
+			if (t[i] == '<' || t[i] == '{') {
+				state = TAG;
+			} else {
+				p.text += t[i];
+			}
+			break;
+		case TAG:
+			if (t[i] == '>' || t[i] == '}') {
+				if (tag == "b") {
+					maybe_content (p);
+					p.bold = true;
+				} else if (tag == "/b") {
+					maybe_content (p);
+					p.bold = false;
+				} else if (tag == "i") {
+					maybe_content (p);
+					p.italic = true;
+				} else if (tag == "/i") {
+					maybe_content (p);
+					p.italic = false;
+				} else if (tag == "u") {
+					maybe_content (p);
+					p.underline = true;
+				} else if (tag == "/u") {
+					maybe_content (p);
+					p.underline = false;
+				}
+				tag.clear ();
+				state = TEXT;
+			} else {
+				tag += t[i];
+			}
+			break;
+		}
+	}
+
+	maybe_content (p);
+}
+
+void
+SubripReader::maybe_content (RawSubtitle& p)
+{
+	if (!p.text.empty ()) {
+		_subs.push_back (p);
+		p.text.clear ();
+	}
+}
diff --git a/src/subrip_reader.h b/src/subrip_reader.h
new file mode 100644
index 0000000..2c69971
--- /dev/null
+++ b/src/subrip_reader.h
@@ -0,0 +1,36 @@
+/*
+    Copyright (C) 2014 Carl Hetherington <cth@carlh.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, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "reader.h"
+#include "time_pair.h"
+
+namespace sub {
+
+class SubripReader : public Reader
+{
+public:
+	SubripReader (FILE* f);
+
+private:
+	TimePair convert_time (std::string t);
+	void convert_line (std::string t, int line_number, TimePair from, TimePair to);
+	void maybe_content (RawSubtitle& p);
+};
+
+}
diff --git a/src/time_pair.h b/src/time_pair.h
index a9c1a09..d4b2c09 100644
--- a/src/time_pair.h
+++ b/src/time_pair.h
@@ -32,6 +32,16 @@ namespace sub {
 class TimePair
 {
 public:
+	TimePair () {}
+	
+	TimePair (FrameTime t)
+		: _frame (t)
+	{}
+	
+	TimePair (MetricTime t)
+		: _metric (t)
+	{}
+	
 	void set_frame (FrameTime t) {
 		_frame = t;
 		_metric = boost::optional<MetricTime> ();
diff --git a/src/wscript b/src/wscript
index ef5c787..160277f 100644
--- a/src/wscript
+++ b/src/wscript
@@ -28,6 +28,7 @@ def build(bld):
                  stl_text_reader.cc
                  stl_util.cc
                  time_pair.cc
+                 subrip_reader.cc
                  subtitle.cc
                  vertical_reference.cc
                  vertical_position.cc