private static int GetNumberOfFollowingEmptyLines(ref PeekStringReader reader)
{
int numberOfEmptyLines = 0;
string peekedLine = reader.PeekLine();
while (peekedLine != null && peekedLine.Length == 0)
{
// The next line is an empty line
numberOfEmptyLines++;
reader.ReadLine();
peekedLine = reader.PeekLine();
}
return(numberOfEmptyLines);
}
public static IList <LyricsLineViewModel> ParseLyrics(Lyrics lyrics)
{
var linesWithTimestamps = new List <LyricsLineViewModel>();
var linesWithoutTimestamps = new List <LyricsLineViewModel>();
var reader = new PeekStringReader(lyrics.Text);
string line;
while (true)
{
// Process 1 line
line = reader.ReadLine();
if (line == null)
{
// No line found, we reached the end. Exit while loop.
break;
}
// Ignore empty lines
if (line.Length == 0)
{
// Process the next line.
continue;
}
// Ignore lines with tags
MatchCollection tagMatches = Regex.Matches(line, @"\[[a-z]+?:.*?\]");
if (tagMatches.Count > 0)
{
// This is a tag: ignore this line and process the next line.
continue;
}
// Check if the line has characters and is enclosed in brackets (starts with [ and ends with ]).
if (!(line.StartsWith("[") && line.LastIndexOf(']') > 0))
{
// This line is not enclosed in brackets, so it cannot have timestamps.
linesWithoutTimestamps.Add(new LyricsLineViewModel(line));
int numberOfEmptyLines = GetNumberOfFollowingEmptyLines(ref reader);
// Add empty lines
AddEmptyLines(numberOfEmptyLines, linesWithoutTimestamps, TimeSpan.Zero);
// Process the next line
continue;
}
// Get all substrings between square brackets for this line
MatchCollection ms = Regex.Matches(line, @"\[.*?\]");
var spans = new List <TimeSpan>();
bool couldParseAllTimestamps = true;
// Loop through all matches
foreach (Match m in ms)
{
var time = TimeSpan.Zero;
string subString = m.Value.Trim('[', ']');
if (FormatUtils.ParseLyricsTime(subString, out time))
{
spans.Add(time);
}
else
{
couldParseAllTimestamps = false;
}
}
// Check if all timestamps could be parsed
if (couldParseAllTimestamps)
{
int startIndex = line.LastIndexOf(']') + 1;
int numberOfEmptyLines = GetNumberOfFollowingEmptyLines(ref reader);
foreach (TimeSpan span in spans)
{
linesWithTimestamps.Add(new LyricsLineViewModel(span, line.Substring(startIndex)));
// Add empty lines
AddEmptyLines(numberOfEmptyLines, linesWithTimestamps, span);
}
}
else
{
// The line has mistakes. Consider it as a line without timestamps.
linesWithoutTimestamps.Add(new LyricsLineViewModel(line));
int numberOfEmptyLines = GetNumberOfFollowingEmptyLines(ref reader);
// Add empty lines
AddEmptyLines(numberOfEmptyLines, linesWithoutTimestamps, TimeSpan.Zero);
}
}
// Order the time stamped lines
linesWithTimestamps = new List <LyricsLineViewModel>(linesWithTimestamps.OrderBy(p => p.Time).ThenByDescending(p => p.Text));
// Merge both collections, lines with timestamps first.
linesWithTimestamps.AddRange(linesWithoutTimestamps);
return(linesWithTimestamps);
}