From 0a745b3a72e172d7e0efe4b2d8ff763b9bccb91e Mon Sep 17 00:00:00 2001
From: Anton Maminov <anton.linux@gmail.com>
Date: Sun, 31 Jul 2022 17:02:12 +0300
Subject: [PATCH] add geohash

---
 shard.yml              | 2 ++
 spec/geo/coord_spec.cr | 9 +++++++++
 src/geo.cr             | 1 +
 src/geo/coord.cr       | 5 +++++
 4 files changed, 17 insertions(+)

diff --git a/shard.yml b/shard.yml
index b89b88b..f586fc0 100644
--- a/shard.yml
+++ b/shard.yml
@@ -8,6 +8,8 @@ dependencies:
     github: geocrystal/haversine
   convex_hull:
     github: geocrystal/convex_hull
+  geohash:
+    github: geocrystal/geohash
 
 development_dependencies:
   ameba:
diff --git a/spec/geo/coord_spec.cr b/spec/geo/coord_spec.cr
index c8a588a..e9bf473 100644
--- a/spec/geo/coord_spec.cr
+++ b/spec/geo/coord_spec.cr
@@ -83,6 +83,15 @@ describe Geo::Coord do
     end
   end
 
+  context "geohash" do
+    context "encode to geohash" do
+      pos = Geo::Coord.new(50.004444, 36.231389)
+
+      it { pos.geohash.should eq("ubcu2rnbuxcx") }
+      it { pos.geohash(5).should eq("ubcu2") }
+    end
+  end
+
   context "to_s" do
     context "is convertible to string" do
       pos = Geo::Coord.new(50.004444, 36.231389)
diff --git a/src/geo.cr b/src/geo.cr
index 433b022..abf09f0 100644
--- a/src/geo.cr
+++ b/src/geo.cr
@@ -1,4 +1,5 @@
 require "convex_hull"
+require "geohash"
 require "./geo/utils"
 require "./geo/coord"
 require "./geo/polygon"
diff --git a/src/geo/coord.cr b/src/geo/coord.cr
index d81d020..094fa4b 100644
--- a/src/geo/coord.cr
+++ b/src/geo/coord.cr
@@ -146,6 +146,11 @@ module Geo
       end
     end
 
+    # Returns a geohash representing coordinates.
+    def geohash(precision = 12)
+      Geohash.encode(lat.to_f, lng.to_f, precision)
+    end
+
     # Returns a string representing coordinates.
     #
     # ```