From 86e69e3401c77753b19ab7b8a0bd1ce3ff3be44d Mon Sep 17 00:00:00 2001
From: evazion <noizave@gmail.com>
Date: Sun, 2 Oct 2022 23:50:54 -0500
Subject: [PATCH] emails: add fix script to delete duplicate email addresses.

In the past it was possible for users to create multiple accounts with
the same email address. We had about 9000 such accounts. This removes
the email address from these accounts.

When multiple accounts have the same email address, the account that
visited the site last gets to keep the address.
---
 app/models/user.rb                       |  1 +
 script/fixes/118_fix_duplicate_emails.rb | 91 ++++++++++++++++++++++++
 2 files changed, 92 insertions(+)
 create mode 100755 script/fixes/118_fix_duplicate_emails.rb

diff --git a/app/models/user.rb b/app/models/user.rb
index 06b06166c..252208c09 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -149,6 +149,7 @@ class User < ApplicationRecord
   scope :deleted, -> { where("name ~ 'user_[0-9]+~*'") }
   scope :undeleted, -> { where("name !~ 'user_[0-9]+~*'") }
   scope :admins, -> { where(level: Levels::ADMIN) }
+  scope :banned, -> { bit_prefs_match(:is_banned, true) }
 
   scope :has_blacklisted_tag, ->(name) { where_regex(:blacklisted_tags, "(^| )[~-]?#{Regexp.escape(name)}( |$)", flags: "ni") }
   scope :has_private_favorites, -> { bit_prefs_match(:enable_private_favorites, true) }
diff --git a/script/fixes/118_fix_duplicate_emails.rb b/script/fixes/118_fix_duplicate_emails.rb
new file mode 100755
index 000000000..904995990
--- /dev/null
+++ b/script/fixes/118_fix_duplicate_emails.rb
@@ -0,0 +1,91 @@
+#!/usr/bin/env ruby
+
+require_relative "base"
+
+# delete fake emails
+with_confirmation do
+  fake_emails = %w[
+    a@a.com
+    a@b.com
+    a@aa.com
+    a@outlook.com
+    a@yahoo.com
+    a@gmail.com
+    a@naver.com
+    1@1.com
+    1@yahoo.com
+    222@222.com
+    aa@bb.com
+    aa@gmail.com
+    aaa@aa.com
+    aaa@gmail.com
+    aaa@yahoo.com
+    aaa@outlook.com
+    aaaa@outlook.com
+    aaaaa@yahoo.com
+    aaaaa@outlook.com
+    aaaaaa@gmail.com
+    abc@gmail.com
+    abc@outlook.com
+    abc@yahoo.com
+    ass@ass.com
+    asd@yahoo.com
+    asdf@gmail.com
+    asdf@yahoo.com
+    abcd@yahoo.com
+    lol@outlook.com
+    bob@gmail.com
+    dan@gmail.com
+    john@yahoo.com
+    danbooru@outlook.com
+    123456789@qq.com
+    asd@asd.asd
+    asdf@asdf.com
+    no@no.no
+    test@example.com
+  ]
+
+  emails = EmailAddress.where(normalized_address: fake_emails)
+
+  emails.each do |email|
+    puts "DELETE #{email.address} (#{email.user.name}##{email.user.id})"
+    email.destroy if ENV.fetch("DELETE", "false").truthy?
+  end
+end
+
+# delete dupe emails belonging to banned users
+with_confirmation do
+  emails = EmailAddress.where(user: User.banned).where(normalized_address: EmailAddress.group(:normalized_address).having("COUNT(*) > 1").select(:normalized_address))
+
+  emails.each do |email|
+    puts "DELETE #{email.address} (#{email.user.name}##{email.user.id})"
+    email.destroy if ENV.fetch("DELETE", "false").truthy?
+  end
+end
+
+# delete dupe emails, keeping the email belonging to the account that visited the site most recently.
+with_confirmation do
+  emails = EmailAddress.group(:normalized_address).having("COUNT(*) > 1").select(:normalized_address, "array_agg(id) AS ids").order(Arel.sql("COUNT(*) DESC, normalized_address"))
+
+  emails.each do |email|
+    dupe_emails = EmailAddress.where(id: email.ids).joins(:user).to_a
+
+    dupe_emails.sort_by! { |dupe_email| [-dupe_email.user.last_logged_in_at.to_i, -dupe_email.user.id] }
+    dupe_emails => [keep, *dupes]
+
+    puts "#{"#{keep.address} (#{keep.user.name}##{keep.user.id})".ljust(60, " ")} DELETE #{dupes.map { |dupe| "#{dupe.address} (#{dupe.user.name}##{dupe.user.id})" }.join(" ")}"
+    dupes.each(&:destroy) if ENV.fetch("DELETE", "false").truthy?
+  end
+
+  emails = EmailAddress.group(:address).having("COUNT(*) > 1").select(:address, "array_agg(id) AS ids").order(Arel.sql("COUNT(*) DESC, address"))
+
+  emails.each do |email|
+    dupe_emails = EmailAddress.where(id: email.ids).joins(:user).to_a
+
+    dupe_emails.sort_by! { |dupe_email| [-dupe_email.user.last_logged_in_at.to_i, -dupe_email.user.id] }
+    dupe_emails => [keep, *dupes]
+
+    puts "#{"#{keep.address} (#{keep.user.name}##{keep.user.id})".ljust(60, " ")} DELETE #{dupes.map { |dupe| "#{dupe.address} (#{dupe.user.name}##{dupe.user.id})" }.join(" ")}"
+    dupes.each(&:destroy) if ENV.fetch("DELETE", "false").truthy?
+  end
+end