fix: Issue with processing variables in outgoing email content (#12799)

Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>
Co-authored-by: Vinay Keerthi <11478411+stonecharioteer@users.noreply.github.com>
Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/helpers/email_helper.rb

@@ -4,6 +4,19 @@ module EmailHelper
     domain.split('.').first
   end
 
+  def render_email_html(content)
+    return '' if content.blank?
+
+    ChatwootMarkdownRenderer.new(content).render_message.to_s
+  end
+
+  # Raise a standard error if any email address is invalid
+  def validate_email_addresses(emails_to_test)
+    emails_to_test&.each do |email|
+      raise StandardError, 'Invalid email address' unless email.match?(URI::MailTo::EMAIL_REGEXP)
+    end
+  end
+
   # ref: https://www.rfc-editor.org/rfc/rfc5233.html
   # This is not a  mandatory requirement for email addresses, but it is a common practice.
   # john+test@xyc.com is the same as john@xyc.com
@@ -21,6 +34,10 @@ module EmailHelper
     end
   end
 
+  def normalize_email_body(content)
+    content.to_s.gsub("\r\n", "\n")
+  end
+
   def modified_liquid_content(email)
     # This regex is used to match the code blocks in the content
     # We don't want to process liquid in code blocks
@@ -29,7 +46,10 @@ module EmailHelper
 
   def message_drops(conversation)
     {
-      'contact' => ContactDrop.new(conversation.contact)
+      'contact' => ContactDrop.new(conversation.contact),
+      'conversation' => ConversationDrop.new(conversation),
+      'inbox' => InboxDrop.new(conversation.inbox),
+      'account' => AccountDrop.new(conversation.account)
     }
   end
 end