rhubarb-lip-sync/src/string_tools.cpp

79 lines
2.1 KiB
C++

#include "string_tools.h"
#include <boost/algorithm/string/trim.hpp>
using std::string;
using std::vector;
vector<string> splitIntoLines(const string& s) {
vector<string> lines;
auto it = s.cbegin();
auto lineBegin = it;
auto end = s.cend();
// Iterate over input string
while (it <= end) {
// Add a new result line when we hit a \n character or the end of the string
if (it == end || *it == '\n') {
string line(lineBegin, it);
// Trim \r characters
boost::algorithm::trim_if(line, [](char c) { return c == '\r'; });
lines.push_back(line);
lineBegin = it + 1;
}
++it;
}
return lines;
}
vector<string> wrapSingleLineString(const string& s, int lineLength) {
if (lineLength <= 0) throw std::invalid_argument("lineLength must be > 0.");
if (s.find('\t') != std::string::npos) throw std::invalid_argument("s must not contain tabs.");
if (s.find('\n') != std::string::npos) throw std::invalid_argument("s must not contain line breaks.");
vector<string> lines;
auto it = s.cbegin();
auto lineBegin = it;
auto lineEnd = it;
auto end = s.cend();
// Iterate over input string
while (it <= end) {
// If we're at a word boundary: update safeLineEnd
if (it == end || *it == ' ') {
lineEnd = it;
}
// If we've hit lineLength or the end of the string: add a new result line
if (it == end || it - lineBegin == lineLength) {
if (lineEnd == lineBegin) {
// The line contains a single word, which is too long. Split mid-word.
lineEnd = it;
}
// Add trimmed line to list
string line(lineBegin, lineEnd);
boost::algorithm::trim_right(line);
lines.push_back(line);
// Resume after the last line, skipping spaces
it = lineEnd;
while (it != end && *it == ' ') ++it;
lineBegin = lineEnd = it;
}
++it;
}
return lines;
}
vector<string> wrapString(const string& s, int lineLength) {
vector<string> lines;
for (string paragraph : splitIntoLines(s)) {
auto paragraphLines = wrapSingleLineString(paragraph, lineLength);
copy(paragraphLines.cbegin(), paragraphLines.cend(), back_inserter(lines));
}
return lines;
}