Repo created

libs/ge0/url_generator.hpp

@@ -0,0 +1,45 @@
+#pragma once
+
+#include <string>
+
+namespace ge0
+{
+// Max number of base64 bytes to encode a geo point.
+inline static int constexpr kMaxPointBytes = 10;
+inline static int constexpr kMaxCoordBits = kMaxPointBytes * 3;
+
+// Generates a short url.
+//
+// URL format:
+//
+//       +------------------  1 byte: zoom level
+//       |+-------+---------  9 bytes: lat,lon
+//       ||       | +--+----  Variable number of bytes: point name
+//       ||       | |  |
+// cm://ZCoordba64/Name
+std::string GenerateShortShowMapUrl(double lat, double lon, double zoomLevel, std::string const & name);
+
+// Generates a geo: uri.
+//
+// - https://datatracker.ietf.org/doc/html/rfc5870
+// - https://developer.android.com/guide/components/intents-common#Maps
+// - https://developers.google.com/maps/documentation/urls/android-intents
+//
+// URL format:
+//
+//     +--------------------------------  lat
+//     |            +-------------------- lon
+//     |            |               +---- zoom
+//     |            |               | +-- url-encoded name
+//     |            |               | |
+//     |            |               | |
+// geo:54.683486138,25.289361259&z=14(Forto%20dvaras)
+std::string GenerateGeoUri(double lat, double lon, double zoom, std::string const & name);
+
+// Exposed for testing.
+char Base64Char(int x);
+int LatToInt(double lat, int maxValue);
+double LonIn180180(double lon);
+int LonToInt(double lon, int maxValue);
+void LatLonToString(double lat, double lon, char * s, size_t nBytes);
+}  // namespace ge0