Statistics for Form Subscriptions

- added statistics_forms table
- added corresponding model to record stats
- record stats whenever someone subscribes via a form

lib/Models/StatisticsForms.php

@@ -0,0 +1,36 @@
+<?php
+namespace MailPoet\Models;
+
+if(!defined('ABSPATH')) exit;
+
+class StatisticsForms extends Model {
+  public static $_table = MP_STATISTICS_FORMS_TABLE;
+
+  function __construct() {
+    parent::__construct();
+  }
+
+  public static function record($form_id) {
+    if($form_id > 0) {
+      $today = date('Y-m-d');
+
+      // check if we already have a record for today
+      $record = self::where('form_id', $form_id)
+        ->where('date', $today)
+        ->findOne();
+
+      if($record !== false) {
+        $record->setExpr('count', 'count + 1')->save();
+      } else {
+        // create a new entry
+        $record = self::create();
+        $record->hydrate(array(
+          'form_id' => $form_id,
+          'date' => $today,
+          'count' => 1
+        ));
+        $record->save();
+      }
+    }
+  }
+}