1 files changed, 56 insertions, 0 deletions
diff --git a/src/Enmarcha.Backend/Services/Processors/AbstractProcessor.cs b/src/Enmarcha.Backend/Services/Processors/AbstractProcessor.cs
new file mode 100644
index 0000000..d6b420f
--- /dev/null
+++ b/src/Enmarcha.Backend/Services/Processors/AbstractProcessor.cs
@@ -0,0 +1,56 @@
+using Enmarcha.Backend.Services;
+
+public abstract class AbstractRealTimeProcessor : IArrivalsProcessor
+{
+    public abstract Task ProcessAsync(ArrivalsContext context);
+
+    protected static List<(double Lat, double Lon)> Decode(string encodedPoints)
+    {
+        if (string.IsNullOrEmpty(encodedPoints))
+            return new List<(double, double)>();
+
+        var poly = new List<(double, double)>();
+        char[] polylineChars = encodedPoints.ToCharArray();
+        int index = 0;
+
+        int currentLat = 0;
+        int currentLng = 0;
+        int next5bits;
+        int sum;
+        int shifter;
+
+        while (index < polylineChars.Length)
+        {
+            // calculate next latitude
+            sum = 0;
+            shifter = 0;
+            do
+            {
+                next5bits = (int)polylineChars[index++] - 63;
+                sum |= (next5bits & 31) << shifter;
+                shifter += 5;
+            } while (next5bits >= 32 && index < polylineChars.Length);
+
+            if (index >= polylineChars.Length)
+                break;
+
+            currentLat += (sum & 1) == 1 ? ~(sum >> 1) : (sum >> 1);
+
+            // calculate next longitude
+            sum = 0;
+            shifter = 0;
+            do
+            {
+                next5bits = (int)polylineChars[index++] - 63;
+                sum |= (next5bits & 31) << shifter;
+                shifter += 5;
+            } while (next5bits >= 32 && index < polylineChars.Length);
+
+            currentLng += (sum & 1) == 1 ? ~(sum >> 1) : (sum >> 1);
+
+            poly.Add((Convert.ToDouble(currentLat) / 100000.0, Convert.ToDouble(currentLng) / 100000.0));
+        }
+
+        return poly;
+    }
+}