#include "ex13_42_TextQuery.h"
#include <sstream>
#include <algorithm>

using std::string;

TextQuery::TextQuery(std::ifstream &ifs) : input(new StrVec)
{
 size_t lineNo = 0;
 for (string line; std::getline(ifs, line); ++lineNo) {
 input->push_back(line);
 std::istringstream line_stream(line);
 for (string text, word; line_stream >> text; word.clear()) {
 // avoid read a word followed by punctuation(such as: word, )
 std::remove_copy_if(text.begin(), text.end(), std::back_inserter(word), ispunct);
 // use reference avoid count of shared_ptr add.
 auto &nos = result[word];
 if (!nos) nos.reset(new std::set<size_t>);
 nos->insert(lineNo);
 }
 }
}

QueryResult TextQuery::query(const string& str) const
{
 // use static just allocate once.
 static std::shared_ptr<std::set<size_t>> nodate(new std::set<size_t>);
 auto found = result.find(str);
 if (found == result.end()) return QueryResult(str, nodate, input);
 else return QueryResult(str, found->second, input);
}

std::ostream& print(std::ostream &out, const QueryResult& qr)
{
 out << qr.word << " occurs " << qr.nos->size() << (qr.nos->size() > 1 ? " times" : " time") << std::endl;
 for (auto i : *qr.nos)
 out << "\t(line " << i+1 << ") " << qr.input->at(i) << std::endl;
 return out;
}