Feature: Add web push notification permission in frontend (#766)

Add webpush notification permission in frontend

Co-authored-by: Sojan <sojan@pepalo.com>

app/services/notification/email_notification_service.rb

@@ -2,11 +2,14 @@ class Notification::EmailNotificationService
   pattr_initialize [:notification!]
 
   def perform
+    # don't send emails if user read the push notification already
+    return if notification.read_at.present?
     return unless user_subscribed_to_notification?
 
     # TODO : Clean up whatever happening over here
+    # Segregate the mailers properly
     AgentNotifications::ConversationNotificationsMailer.public_send(notification
-      .notification_type.to_s, notification.primary_actor, notification.user).deliver_later
+      .notification_type.to_s, notification.primary_actor, notification.user).deliver_now
   end
 
   private

app/services/notification/push_notification_service.rb

@@ -1,17 +1,73 @@
 class Notification::PushNotificationService
+  include Rails.application.routes.url_helpers
+
   pattr_initialize [:notification!]
 
   def perform
     return unless user_subscribed_to_notification?
-    # TODO: implement the push delivery logic here
+
+    notification_subscriptions.each do |subscription|
+      send_browser_push(subscription) if subscription.browser_push?
+    end
   end
 
   private
 
+  delegate :user, to: :notification
+  delegate :notification_subscriptions, to: :user
+  delegate :notification_settings, to: :user
+
   def user_subscribed_to_notification?
-    notification_setting = notification.user.notification_settings.find_by(account_id: notification.account.id)
+    notification_setting = notification_settings.find_by(account_id: notification.account.id)
     return true if notification_setting.public_send("push_#{notification.notification_type}?")
 
     false
   end
+
+  def conversation
+    @conversation ||= notification.primary_actor
+  end
+
+  def push_message_title
+    if notification.notification_type == 'conversation_creation'
+      return "A new conversation [ID -#{conversation.display_id}] has been created in #{conversation.inbox.name}"
+    end
+
+    if notification.notification_type == 'conversation_assignment'
+      return "A new conversation [ID -#{conversation.display_id}] has been assigned to you."
+    end
+
+    ''
+  end
+
+  def push_message
+    {
+      title: push_message_title,
+      tag: "#{notification.notification_type}_#{conversation.display_id}",
+      url: push_url
+    }
+  end
+
+  def push_url
+    app_account_conversation_url(account_id: conversation.account_id, id: conversation.display_id)
+  end
+
+  def send_browser_push(subscription)
+    Webpush.payload_send(
+      message: JSON.generate(push_message),
+      endpoint: subscription.subscription_attributes['endpoint'],
+      p256dh: subscription.subscription_attributes['p256dh'],
+      auth: subscription.subscription_attributes['auth'],
+      vapid: {
+        subject: push_url,
+        public_key: ENV['VAPID_PUBLIC_KEY'],
+        private_key: ENV['VAPID_PRIVATE_KEY']
+      },
+      ssl_timeout: 5,
+      open_timeout: 5,
+      read_timeout: 5
+    )
+  rescue Webpush::ExpiredSubscription
+    subscription.destroy!
+  end
 end