back photo + event tags and persons

back/DataModels/RankingModel.cs

@@ -0,0 +1,36 @@
+namespace back.DataModels;
+
+public class RankingModel
+{
+    private int totalVotes;
+    private int upVotes;
+    private int downVotes;
+
+    public RankingModel(int totalVotes, int upVotes = 0, int downVotes = 0)
+    {
+        this.totalVotes = totalVotes;
+        this.upVotes = upVotes;
+        this.downVotes = downVotes;
+    }
+
+    public void DownVote()
+    {
+        downVotes++;
+        totalVotes++;
+    }
+
+    public void UpVote()
+    {
+        upVotes++;
+        totalVotes++;
+    }
+
+    public double Score
+    {
+        get
+        {
+            if (totalVotes == 0) return 0;
+            return (double)(upVotes - downVotes) / totalVotes;
+        }
+    }
+}