From eb117c62522053c57d094a5aa3bd5383ab5c5fd8 Mon Sep 17 00:00:00 2001
From: vng <viktor.govako@gmail.com>
Date: Fri, 21 Mar 2014 14:01:04 +0300
Subject: [PATCH] Correct parsing of N, S, E, W control symbols in LatLon ->
 DMS.

---
 search/latlon_match.cpp                   | 40 +++++++++++++++++++++--
 search/search_tests/latlon_match_test.cpp | 15 +++++++++
 2 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/search/latlon_match.cpp b/search/latlon_match.cpp
index 876c3d84b0..3c510adec9 100644
--- a/search/latlon_match.cpp
+++ b/search/latlon_match.cpp
@@ -22,8 +22,7 @@ template <typename CharT> void SkipSpaces(CharT * & s)
 template <typename CharT> void Skip(CharT * & s)
 {
   while (*s && (*s == ' ' || *s == '\t' || *s == ',' || *s == ';' ||
-                *s == ':' || *s == '.' || *s == '(' || *s == ')' ||
-                *s == 'N' || *s == 'E' || *s == 'n' || *s == 'e'))
+                *s == ':' || *s == '.' || *s == '(' || *s == ')'))
     ++s;
 }
 
@@ -136,6 +135,25 @@ int GetDMSIndex(char const * & s)
   }
 }
 
+void SkipNSEW(char const * & s, char const * (&arrPos) [4])
+{
+  Skip(s);
+
+  int ind;
+  switch (*s)
+  {
+  case 'N': case 'n': ind = 0; break;
+  case 'S': case 's': ind = 1; break;
+  case 'E': case 'e': ind = 2; break;
+  case 'W': case 'w': ind = 3; break;
+  default: return;
+  }
+
+  arrPos[ind] = s++;
+
+  Skip(s);
+}
+
 }
 
 bool MatchLatLonDegree(string const & query, double & lat, double & lon)
@@ -145,11 +163,14 @@ bool MatchLatLonDegree(string const & query, double & lat, double & lon)
 
   int base = 0;
 
+  // Positions of N, S, E, W symbols
+  char const * arrPos[] = { 0, 0, 0, 0 };
+
   char const * s = query.c_str();
   while (true)
   {
     char const * s1 = s;
-    Skip(s);
+    SkipNSEW(s, arrPos);
     if (!*s)
     {
       // End of the string - check matching.
@@ -210,12 +231,25 @@ bool MatchLatLonDegree(string const & query, double & lat, double & lon)
     return false;
   }
 
+  if ((arrPos[0] && arrPos[1]) || (arrPos[2] && arrPos[3]))
+  {
+    // control symbols should match only once
+    return false;
+  }
+
+  // Calculate Lat, Lon with correct sign.
   lat = fabs(v[0].first) + v[1].first / 60.0 + v[2].first / 3600.0;
   if (v[0].first < 0.0) lat = -lat;
 
   lon = fabs(v[3].first) + v[4].first / 60.0 + v[5].first / 3600.0;
   if (v[3].first < 0.0) lon = -lon;
 
+  if (max(arrPos[0], arrPos[1]) > max(arrPos[2], arrPos[3]))
+    swap(lat, lon);
+
+  if (arrPos[1]) lat = -lat;
+  if (arrPos[3]) lon = -lon;
+
   if (lon > 180.0) lon -= 360.0;
   if (lon < -180.0) lon += 360.0;
 
diff --git a/search/search_tests/latlon_match_test.cpp b/search/search_tests/latlon_match_test.cpp
index ded099e972..9d81387db8 100644
--- a/search/search_tests/latlon_match_test.cpp
+++ b/search/search_tests/latlon_match_test.cpp
@@ -104,4 +104,19 @@ UNIT_TEST(LatLon_Degree_Match)
   TEST(MatchLatLonDegree("55°45’20.9916\"N, 37°37’3.6228\"E hsdfjgkdsjbv", lat, lon), ());
   TEST_ALMOST_EQUAL(lat, 55.755831, ());
   TEST_ALMOST_EQUAL(lon, 37.617673, ());
+
+  TEST(MatchLatLonDegree("55°45′20.9916″S, 37°37′3.6228″W", lat, lon), ());
+  TEST_ALMOST_EQUAL(lat, -55.755831, ());
+  TEST_ALMOST_EQUAL(lon, -37.617673, ());
+
+  TEST(MatchLatLonDegree("W55°45′20.9916″, S37°37′3.6228″", lat, lon), ());
+  TEST_ALMOST_EQUAL(lon, -55.755831, ());
+  TEST_ALMOST_EQUAL(lat, -37.617673, ());
+
+  TEST(MatchLatLonDegree("55°45′20.9916″ W 37°37′3.6228″ N", lat, lon), ());
+  TEST_ALMOST_EQUAL(lon, -55.755831, ());
+  TEST_ALMOST_EQUAL(lat, 37.617673, ());
+
+  TEST(!MatchLatLonDegree("55°45′20.9916″W 37°37′3.6228″E", lat, lon), ());
+  TEST(!MatchLatLonDegree("N55°45′20.9916″ S37°37′3.6228″", lat, lon), ());
 }