1 files changed, 15 insertions, 0 deletions
diff --git a/models/polls/poll.model.ts b/models/polls/poll.model.ts
index 7f6be9a..6749e5c 100644
--- a/models/polls/poll.model.ts
+++ b/models/polls/poll.model.ts
@@ -1,5 +1,20 @@
 import { Model, model } from 'mongoose';
 import { PollSchema, pollSchema } from './poll.schema';
+import { Types } from 'mongoose';
+import { Which } from 'which-types';
+
+pollSchema.methods.vote = function(userId: string, which: Which): PollSchema {
+  const participants: Types.ObjectId[] = ['left', 'right'].reduce((acc, option) => {
+    const { votes } = this.contents[option];
+    return acc.concat(votes);
+  }, []);
+
+  if (!participants.some(user => user.equals(userId))) {
+    this.contents[which].votes.push(userId);
+  }
+
+  return this.save();
+}
 
 export default model<PollSchema, Model<PollSchema>>('Poll', pollSchema);