Replace EmailHelper module with normalizes via model concern (#35702)

app/models/canonical_email_block.rb

@@ -12,24 +12,29 @@
 #
 
 class CanonicalEmailBlock < ApplicationRecord
-  include EmailHelper
+  include CanonicalEmail
   include Paginable
 
   belongs_to :reference_account, class_name: 'Account', optional: true
 
   validates :canonical_email_hash, presence: true, uniqueness: true
 
-  scope :matching_email, ->(email) { where(canonical_email_hash: email_to_canonical_email_hash(email)) }
+  scope :matching_email, ->(email) { where(canonical_email_hash: digest(normalize_value_for(:email, email))) }
+
+  def self.block?(email)
+    matching_email(email).exists?
+  end
+
+  def self.digest(value)
+    Digest::SHA256.hexdigest(value)
+  end
 
   def to_log_human_identifier
     canonical_email_hash
   end
 
   def email=(email)
-    self.canonical_email_hash = email_to_canonical_email_hash(email)
-  end
-
-  def self.block?(email)
-    matching_email(email).exists?
+    super
+    self.canonical_email_hash = self.class.digest(self.email)
   end
 end

app/models/concerns/canonical_email.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module CanonicalEmail
+  extend ActiveSupport::Concern
+
+  included do
+    normalizes :email, with: ->(value) { canonicalize_email(value) }
+  end
+
+  class_methods do
+    def canonicalize_email(email)
+      email
+        .downcase
+        .split('@', 2)
+        .then { |local, domain| [canonical_username(local), domain] }
+        .join('@')
+    end
+
+    def canonical_username(username)
+      username
+        .to_s
+        .delete('.')
+        .split('+', 2)
+        .first
+    end
+  end
+end