/*
 * Copyright (c) 2010-2013 Remko Tronçon
 * Licensed under the GNU General Public License v3.
 * See Documentation/Licenses/GPLv3.txt for more information.
 */

#include <SwifTools/Linkify.h>

#include <boost/regex.hpp>
#include <sstream>
#include <iostream>

namespace Swift {

static boost::regex linkifyRegexp("^(https?://|xmpp:).*");

std::string Linkify::linkify(const std::string& input) {
	std::ostringstream result;
	std::vector<char> currentURL;
	bool inURL = false;
	for (size_t i = 0; i < input.size(); ++i) {
		char c = input[i];
		if (inURL) {
			if (c != ' ' && c != '\t' && c != '\n' && !(c == '*' && i == input.size() - 1 && input[0] == '*')) {
				currentURL.push_back(c);
			}
			else {
				std::string url(&currentURL[0], currentURL.size());
				result << "<a href=\"" << url << "\">" <<  url << "</a>";
				currentURL.clear();
				inURL = false;
				result << c;
			}
		}
		else {
			if (boost::regex_match(input.substr(i, 8), linkifyRegexp)) {
				currentURL.push_back(c);
				inURL = true;
			}
			else {
				result << c;
			}
		}
	}
	if (!currentURL.empty()) {
		std::string url(&currentURL[0], currentURL.size());
		result << "<a href=\"" << url << "\">" <<  url << "</a>";
	}
	return std::string(result.str());
}

std::pair<std::vector<std::string>, size_t> Linkify::splitLink(const std::string& input) {
	std::vector<std::string> result;
	std::pair<std::vector<std::string>, size_t> pair;
	std::vector<char> currentURL;
	bool inURL = false;
	size_t urlStartsAt = 0;
	for (size_t i = 0; i < input.size(); ++i) {
		char c = input[i];
		if (inURL) {
			if (c != ' ' && c != '\t' && c != '\n' && !(c == '*' && i == input.size() - 1 && input[0] == '*')) {
				// Keep parsing
			}
			else {
				std::string url(input.substr(urlStartsAt, i - urlStartsAt));
				result.push_back(url);
				inURL = false;
				size_t remaining = input.size() - i;
				if (remaining > 0) {
					result.push_back(input.substr(i, remaining));
				}
				pair.first = result;
				pair.second = urlStartsAt == 0 ? 0 : 1;
				return pair;
			}
		}
		else {
			if (boost::regex_match(input.substr(i, 8), linkifyRegexp)) {
				urlStartsAt = i;
				inURL = true;
				if (i > 0) {
					result.push_back(input.substr(0, i));
				}
			}
			else {
				// Just keep swimming
			}
		}
	}
	if (urlStartsAt > 0 || inURL) {
		std::string url(input.substr(urlStartsAt, input.size() - urlStartsAt));
		result.push_back(url);
		pair.first = result;
		pair.second = urlStartsAt == 0 ? 0 : 1;
	}
	else {
		pair.first.push_back(input);
		pair.second = 1;
	}
	return pair;
}

}