Merge pull request #95 from kiwix/geo_loc

Add small API to do geo query.

include/searcher.h

@@ -67,6 +67,10 @@ class Searcher
               unsigned int resultStart,
               unsigned int resultEnd,
               const bool verbose = false);
+  void geo_search(float latitude, float longitude, float distance,
+                  unsigned int resultStart,
+                  unsigned int resultEnd,
+                  const bool verbose = false);
   void suggestions(std::string& search, const bool verbose = false);
   Result* getNextResult();
   void restart_search();

src/searcher.cpp

@@ -176,6 +176,63 @@ void Searcher::search(std::string& search,
   return;
 }
 
+
+void Searcher::geo_search(float latitude, float longitude, float distance,
+                          unsigned int resultStart,
+                          unsigned int resultEnd,
+                          const bool verbose)
+{
+  this->reset();
+
+  if (verbose == true) {
+    cout << "Performing geo query `" << distance << "&(" << latitude << ";" << longitude << ")'" << endl;
+  }
+
+  /* If resultEnd & resultStart inverted */
+  if (resultStart > resultEnd) {
+    resultEnd += resultStart;
+    resultStart = resultEnd - resultStart;
+    resultEnd -= resultStart;
+  }
+
+  /* Try to find results */
+  if (resultStart == resultEnd) {
+    return;
+  }
+
+  if (internal->_xapianSearcher) {
+    return;
+  }
+
+  /* Avoid big researches */
+  this->resultCountPerPage = resultEnd - resultStart;
+  if (this->resultCountPerPage > MAX_SEARCH_LEN) {
+    resultEnd = resultStart + MAX_SEARCH_LEN;
+    this->resultCountPerPage = MAX_SEARCH_LEN;
+  }
+
+  /* Perform the search */
+  std::ostringstream oss;
+  oss << "Articles located less than " << distance << " meters of " << latitude << ";" << longitude;
+  this->searchPattern = oss.str();
+  this->resultStart = resultStart;
+  this->resultEnd = resultEnd;
+
+  std::vector<const zim::File*> zims;
+  for (auto current = this->readers.begin(); current != this->readers.end();
+       current++) {
+    zims.push_back((*current)->getZimFileHandler());
+  }
+  zim::Search* search = new zim::Search(zims);
+  search->set_query("");
+  search->set_georange(latitude, longitude, distance);
+  search->set_range(resultStart, resultEnd);
+  internal->_search = search;
+  internal->current_iterator = internal->_search->begin();
+  this->estimatedResultCount = internal->_search->get_matches_estimated();
+}
+
+
 void Searcher::restart_search()
 {
   if (internal->_xapianSearcher) {