Cast Invoice::reminders to json

app/Models/Invoice.php

@@ -35,6 +35,10 @@ class Invoice extends Model implements IDs
 {
 	use PushNew,ScopeActive;
 
+	protected $casts = [
+		'reminders'=>'json',
+	];
+
 	protected $dates = [
 		'due_at',
 	];
@@ -414,16 +418,17 @@ class Invoice extends Model implements IDs
 
 	/**
 	 * @param string $key
-	 * @return string
+	 * @return array
 	 * @todo Ugly hack to update reminders
 	 */
-	public function reminders(string $key) {
-		$r = json_decode($this->reminders);
-
+	public function reminders(string $key): array
+	{
+		$r = $this->reminders;
 		if (! Arr::get($r,$key)) {
 			$r[$key] = time();
-			return json_encode($r);
 		}
+
+		return $r;
 	}
 
 	/**
@@ -432,7 +437,8 @@ class Invoice extends Model implements IDs
 	 * @param array $options
 	 * @return bool
 	 */
-	public function save(array $options = []) {
+	public function save(array $options = [])
+	{
 		// Automatically set the date_due attribute for new records.
 		if (! $this->exists AND ! $this->due_at) {
 			$this->due_at = $this->items->min('start_at');