Aegisub/core/subtitle_format_srt.cpp

// Copyright (c) 2006, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//   * Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//   * Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//   * Neither the name of the Aegisub Group nor the names of its contributors
//     may be used to endorse or promote products derived from this software
//     without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//


///////////
// Headers
#include "subtitle_format_srt.h"
#include "text_file_reader.h"
#include "text_file_writer.h"
#include "ass_dialogue.h"
#include "ass_file.h"


/////////////
// Can read?
bool SRTSubtitleFormat::CanReadFile(wxString filename) {
	return (filename.Right(4).Lower() == _T(".srt"));
}


/////////////
// Read file
void SRTSubtitleFormat::ReadFile(wxString filename,wxString encoding) {
	using namespace std;

	// Reader
	TextFileReader file(filename,encoding);

	// Default
	LoadDefault();

	// Parse file
	int linen = 1;
	int fileLine = 0;
	int mode = 0;
	long templ;
	AssDialogue *line = NULL;
	while (file.HasMoreLines()) {
		// Reads line
		wxString curLine = file.ReadLineFromFile();
		fileLine++;

		switch (mode) {
			case 0:
				// Checks if there is anything to read
				if (curLine.IsEmpty()) continue;

				// Check if it's a line number
				if (!curLine.IsNumber()) {
					Clear();
					throw wxString::Format(_T("Parse error on entry %i at line %i (expecting line number). Possible malformed file."),linen,fileLine);
				}

				// Read line number
				curLine.ToLong(&templ);
				if (templ != linen) {
					linen = templ;
				}
				line = new AssDialogue();
				mode = 1;
				break;

			case 1:
				// Read timestamps
				if (curLine.substr(13,3) != _T("-->")) {
					Clear();
					throw wxString::Format(_T("Parse error on entry %i at line %i (expecting timestamps). Possible malformed file."),linen,fileLine);
				}
				line->Start.ParseSRT(curLine.substr(0,12));
				line->End.ParseSRT(curLine.substr(17,12));
				mode = 2;
				break;

			case 2:
				// Checks if it's done
				if (curLine.IsEmpty()) {
					mode = 0;
					linen++;
					line->group = _T("[Events]");
					line->Style = _T("Default");
					line->Comment = false;
					line->UpdateData();
					line->ParseSRTTags();
					line->StartMS = line->Start.GetMS();
					Line->push_back(line);
					break;
				}
				// Append text
				if (line->Text != _T("")) line->Text += _T("\\N");
				line->Text += curLine;
				break;
		}
	}
}


//////////////
// Can write?
bool SRTSubtitleFormat::CanWriteFile(wxString filename) {
	return (filename.Right(4).Lower() == _T(".srt"));
}


//////////////
// Write file
void SRTSubtitleFormat::WriteFile(wxString _filename,wxString encoding) {
	// Open file
	TextFileWriter file(_filename,encoding);

	// Convert to SRT
	CreateCopy();
	ConvertToSRT();

	// Write lines
	int i=1;
	using std::list;
	for (list<AssEntry*>::iterator cur=Line->begin();cur!=Line->end();cur++) {
		AssDialogue *current = AssEntry::GetAsDialogue(*cur);
		if (current) {
			// Get line
			if (current->Comment) throw _T("Unexpected line type (comment)");

			// Write line
			file.WriteLineToFile(wxString::Format(_T("%i"),i));
			file.WriteLineToFile(current->Start.GetSRTFormated() + _T(" --> ") + current->End.GetSRTFormated());
			file.WriteLineToFile(current->Text);
			file.WriteLineToFile(_T(""));

			i++;
		}
		else throw _T("Unexpected line type");
	}
	ClearCopy();
}


///////////////////////
// Convert line to SRT
void SRTSubtitleFormat::DialogueToSRT(AssDialogue *current,std::list<AssEntry*>::iterator prev) {
	using std::list;
	AssDialogue *previous;
	if (prev != Line->end()) previous = AssEntry::GetAsDialogue(*prev);
	else previous = NULL;

	// Strip ASS tags
	current->ConvertTagsToSRT();

	// Join equal lines
	if (previous != NULL) {
		if (previous->Text == current->Text) {
			if (abs(current->Start.GetMS() - previous->End.GetMS()) < 20) {
				current->Start = (current->Start < previous->Start ? current->Start : previous->Start);
				current->End = (current->End > previous->End ? current->End : previous->End);
				delete *prev;
				Line->erase(prev);
			}
		}
	}

	// Fix line breaks
	current->Text.Replace(_T("\\n"),_T("\r\n"),true);
	current->Text.Replace(_T("\\N"),_T("\r\n"),true);
	current->Text.Replace(_T("\r\n\r\n"),_T("\r\n"),true);
}


//////////////////////////////
// Converts whole file to SRT
void SRTSubtitleFormat::ConvertToSRT () {
	using std::list;
	list<AssEntry*>::iterator next;
	list<AssEntry*>::iterator prev = Line->end();

	// Sort lines
	Line->sort(LessByPointedToValue<AssEntry>());

	// Process lines
	bool notfirst = false;
	for (list<AssEntry*>::iterator cur=Line->begin();cur!=Line->end();cur=next) {
		next = cur;
		next++;

		// Dialogue line (not comment)
		AssDialogue *current = AssEntry::GetAsDialogue(*cur);
		if (current && !current->Comment) {
			DialogueToSRT(current,prev);
			notfirst = true;
			prev = cur;
		}

		// Other line, delete it
		else {
			delete *cur;
			Line->erase(cur);
		}
	}
}