mastodon/app/models/account.rb

# frozen_string_literal: true
# == Schema Information
#
# Table name: accounts
#
#  id                      :integer          not null, primary key
#  username                :string           default(""), not null
#  domain                  :string
#  secret                  :string           default(""), not null
#  private_key             :text
#  public_key              :text             default(""), not null
#  remote_url              :string           default(""), not null
#  salmon_url              :string           default(""), not null
#  hub_url                 :string           default(""), not null
#  created_at              :datetime         not null
#  updated_at              :datetime         not null
#  note                    :text             default(""), not null
#  display_name            :string           default(""), not null
#  uri                     :string           default(""), not null
#  url                     :string
#  avatar_file_name        :string
#  avatar_content_type     :string
#  avatar_file_size        :integer
#  avatar_updated_at       :datetime
#  header_file_name        :string
#  header_content_type     :string
#  header_file_size        :integer
#  header_updated_at       :datetime
#  avatar_remote_url       :string
#  subscription_expires_at :datetime
#  silenced                :boolean          default(FALSE), not null
#  suspended               :boolean          default(FALSE), not null
#  locked                  :boolean          default(FALSE), not null
#  header_remote_url       :string           default(""), not null
#  statuses_count          :integer          default(0), not null
#  followers_count         :integer          default(0), not null
#  following_count         :integer          default(0), not null
#  last_webfingered_at     :datetime
#  inbox_url               :string           default(""), not null
#  outbox_url              :string           default(""), not null
#  shared_inbox_url        :string           default(""), not null
#  followers_url           :string           default(""), not null
#  protocol                :integer          default("ostatus"), not null
#  memorial                :boolean          default(FALSE), not null
#  moved_to_account_id     :integer
#  featured_collection_url :string
#

class Account < ApplicationRecord
  USERNAME_RE = /[a-z0-9_]+([a-z0-9_\.]+[a-z0-9_]+)?/i
  MENTION_RE  = /(?<=^|[^\/[:word:]])@((#{USERNAME_RE})(?:@[a-z0-9\.\-]+[a-z0-9]+)?)/i

  include AccountAvatar
  include AccountFinderConcern
  include AccountHeader
  include AccountInteractions
  include Attachmentable
  include Remotable
  include Paginable

  MAX_NOTE_LENGTH = 500

  enum protocol: [:ostatus, :activitypub]

  # Local users
  has_one :user, inverse_of: :account

  validates :username, presence: true

  # Remote user validations
  validates :username, uniqueness: { scope: :domain, case_sensitive: true }, if: -> { !local? && will_save_change_to_username? }

  # Local user validations
  validates :username, format: { with: /\A[a-z0-9_]+\z/i }, length: { maximum: 30 }, if: -> { local? && will_save_change_to_username? }
  validates_with UniqueUsernameValidator, if: -> { local? && will_save_change_to_username? }
  validates_with UnreservedUsernameValidator, if: -> { local? && will_save_change_to_username? }
  validates :display_name, length: { maximum: 30 }, if: -> { local? && will_save_change_to_display_name? }
  validate :note_length_does_not_exceed_length_limit, if: -> { local? && will_save_change_to_note? }

  # Timelines
  has_many :stream_entries, inverse_of: :account, dependent: :destroy
  has_many :statuses, inverse_of: :account, dependent: :destroy
  has_many :favourites, inverse_of: :account, dependent: :destroy
  has_many :mentions, inverse_of: :account, dependent: :destroy
  has_many :notifications, inverse_of: :account, dependent: :destroy

  # Pinned statuses
  has_many :status_pins, inverse_of: :account, dependent: :destroy
  has_many :pinned_statuses, -> { reorder('status_pins.created_at DESC') }, through: :status_pins, class_name: 'Status', source: :status

  # Media
  has_many :media_attachments, dependent: :destroy

  # PuSH subscriptions
  has_many :subscriptions, dependent: :destroy

  # Report relationships
  has_many :reports
  has_many :targeted_reports, class_name: 'Report', foreign_key: :target_account_id

  # Moderation notes
  has_many :account_moderation_notes, dependent: :destroy
  has_many :targeted_moderation_notes, class_name: 'AccountModerationNote', foreign_key: :target_account_id, dependent: :destroy

  # Lists
  has_many :list_accounts, inverse_of: :account, dependent: :destroy
  has_many :lists, through: :list_accounts

  # Account migrations
  belongs_to :moved_to_account, class_name: 'Account', optional: true

  scope :remote, -> { where.not(domain: nil) }
  scope :local, -> { where(domain: nil) }
  scope :without_followers, -> { where(followers_count: 0) }
  scope :with_followers, -> { where('followers_count > 0') }
  scope :expiring, ->(time) { remote.where.not(subscription_expires_at: nil).where('subscription_expires_at < ?', time) }
  scope :partitioned, -> { order('row_number() over (partition by domain)') }
  scope :silenced, -> { where(silenced: true) }
  scope :suspended, -> { where(suspended: true) }
  scope :recent, -> { reorder(id: :desc) }
  scope :alphabetic, -> { order(domain: :asc, username: :asc) }
  scope :by_domain_accounts, -> { group(:domain).select(:domain, 'COUNT(*) AS accounts_count').order('accounts_count desc') }
  scope :matches_username, ->(value) { where(arel_table[:username].matches("#{value}%")) }
  scope :matches_display_name, ->(value) { where(arel_table[:display_name].matches("#{value}%")) }
  scope :matches_domain, ->(value) { where(arel_table[:domain].matches("%#{value}%")) }

  delegate :email,
           :current_sign_in_ip,
           :current_sign_in_at,
           :confirmed?,
           :admin?,
           :moderator?,
           :staff?,
           :locale,
           to: :user,
           prefix: true,
           allow_nil: true

  delegate :filtered_languages, to: :user, prefix: false, allow_nil: true

  def local?
    domain.nil?
  end

  def moved?
    moved_to_account_id.present?
  end

  def acct
    local? ? username : "#{username}@#{domain}"
  end

  def local_username_and_domain
    "#{username}@#{Rails.configuration.x.local_domain}"
  end

  def to_webfinger_s
    "acct:#{local_username_and_domain}"
  end

  def subscribed?
    subscription_expires_at.present?
  end

  def possibly_stale?
    last_webfingered_at.nil? || last_webfingered_at <= 1.day.ago
  end

  def refresh!
    return if local?
    ResolveAccountService.new.call(acct)
  end

  def unsuspend!
    transaction do
      user&.enable! if local?
      update!(suspended: false)
    end
  end

  def memorialize!
    transaction do
      user&.disable! if local?
      update!(memorial: true)
    end
  end

  def keypair
    @keypair ||= OpenSSL::PKey::RSA.new(private_key || public_key)
  end

  def magic_key
    modulus, exponent = [keypair.public_key.n, keypair.public_key.e].map do |component|
      result = []

      until component.zero?
        result << [component % 256].pack('C')
        component >>= 8
      end

      result.reverse.join
    end

    (['RSA'] + [modulus, exponent].map { |n| Base64.urlsafe_encode64(n) }).join('.')
  end

  def subscription(webhook_url)
    @subscription ||= OStatus2::Subscription.new(remote_url, secret: secret, webhook: webhook_url, hub: hub_url)
  end

  def save_with_optional_media!
    save!
  rescue ActiveRecord::RecordInvalid
    self.avatar              = nil
    self.header              = nil
    self[:avatar_remote_url] = ''
    self[:header_remote_url] = ''
    save!
  end

  def object_type
    :person
  end

  def to_param
    username
  end

  def excluded_from_timeline_account_ids
    Rails.cache.fetch("exclude_account_ids_for:#{id}") { blocking.pluck(:target_account_id) + blocked_by.pluck(:account_id) + muting.pluck(:target_account_id) }
  end

  def excluded_from_timeline_domains
    Rails.cache.fetch("exclude_domains_for:#{id}") { domain_blocks.pluck(:domain) }
  end

  def preferred_inbox_url
    shared_inbox_url.presence || inbox_url
  end

  class << self
    def readonly_attributes
      super - %w(statuses_count following_count followers_count)
    end

    def domains
      reorder(nil).pluck('distinct accounts.domain')
    end

    def inboxes
      urls = reorder(nil).where(protocol: :activitypub).pluck("distinct coalesce(nullif(accounts.shared_inbox_url, ''), accounts.inbox_url)")
      DeliveryFailureTracker.filter(urls)
    end

    def triadic_closures(account, limit: 5, offset: 0)
      sql = <<-SQL.squish
        WITH first_degree AS (
          SELECT target_account_id
          FROM follows
          WHERE account_id = :account_id
        )
        SELECT accounts.*
        FROM follows
        INNER JOIN accounts ON follows.target_account_id = accounts.id
        WHERE
          account_id IN (SELECT * FROM first_degree)
          AND target_account_id NOT IN (SELECT * FROM first_degree)
          AND target_account_id NOT IN (:excluded_account_ids)
          AND accounts.suspended = false
        GROUP BY target_account_id, accounts.id
        ORDER BY count(account_id) DESC
        OFFSET :offset
        LIMIT :limit
      SQL

      excluded_account_ids = account.excluded_from_timeline_account_ids + [account.id]

      find_by_sql(
        [sql, { account_id: account.id, excluded_account_ids: excluded_account_ids, limit: limit, offset: offset }]
      )
    end

    def search_for(terms, limit = 10)
      textsearch, query = generate_query_for_search(terms)

      sql = <<-SQL.squish
        SELECT
          accounts.*,
          ts_rank_cd(#{textsearch}, #{query}, 32) AS rank
        FROM accounts
        WHERE #{query} @@ #{textsearch}
          AND accounts.suspended = false
          AND accounts.moved_to_account_id IS NULL
        ORDER BY rank DESC
        LIMIT ?
      SQL

      find_by_sql([sql, limit])
    end

    def advanced_search_for(terms, account, limit = 10, following = false)
      textsearch, query = generate_query_for_search(terms)

      if following
        sql = <<-SQL.squish
          WITH first_degree AS (
            SELECT target_account_id
            FROM follows
            WHERE account_id = ?
          )
          SELECT
            accounts.*,
            (count(f.id) + 1) * ts_rank_cd(#{textsearch}, #{query}, 32) AS rank
          FROM accounts
          LEFT OUTER JOIN follows AS f ON (accounts.id = f.account_id AND f.target_account_id = ?) OR (accounts.id = f.target_account_id AND f.account_id = ?)
          WHERE accounts.id IN (SELECT * FROM first_degree)
            AND #{query} @@ #{textsearch}
            AND accounts.suspended = false
            AND accounts.moved_to_account_id IS NULL
          GROUP BY accounts.id
          ORDER BY rank DESC
          LIMIT ?
        SQL

        find_by_sql([sql, account.id, account.id, account.id, limit])
      else
        sql = <<-SQL.squish
          SELECT
            accounts.*,
            (count(f.id) + 1) * ts_rank_cd(#{textsearch}, #{query}, 32) AS rank
          FROM accounts
          LEFT OUTER JOIN follows AS f ON (accounts.id = f.account_id AND f.target_account_id = ?) OR (accounts.id = f.target_account_id AND f.account_id = ?)
          WHERE #{query} @@ #{textsearch}
            AND accounts.suspended = false
            AND accounts.moved_to_account_id IS NULL
          GROUP BY accounts.id
          ORDER BY rank DESC
          LIMIT ?
        SQL

        find_by_sql([sql, account.id, account.id, limit])
      end
    end

    private

    def generate_query_for_search(terms)
      terms      = Arel.sql(connection.quote(terms.gsub(/['?\\:]/, ' ')))
      textsearch = "(setweight(to_tsvector('simple', accounts.display_name), 'A') || setweight(to_tsvector('simple', accounts.username), 'B') || setweight(to_tsvector('simple', coalesce(accounts.domain, '')), 'C'))"
      query      = "to_tsquery('simple', ''' ' || #{terms} || ' ''' || ':*')"

      [textsearch, query]
    end
  end

  before_create :generate_keys
  before_validation :normalize_domain
  before_validation :prepare_contents, if: :local?

  private

  def prepare_contents
    display_name&.strip!
    note&.strip!
  end

  def generate_keys
    return unless local?

    keypair = OpenSSL::PKey::RSA.new(Rails.env.test? ? 512 : 2048)
    self.private_key = keypair.to_pem
    self.public_key  = keypair.public_key.to_pem
  end

  YAML_START = "---\r\n"
  YAML_END = "\r\n...\r\n"

  def note_length_does_not_exceed_length_limit
    note_without_metadata = note
    if note.start_with? YAML_START
      idx = note.index YAML_END
      unless idx.nil?
        note_without_metadata = note[(idx + YAML_END.length) .. -1]
      end
    end
    if note_without_metadata.mb_chars.grapheme_length > MAX_NOTE_LENGTH
      errors.add(:note, "can't be longer than 500 graphemes")
    end
  end

  def normalize_domain
    return if local?

    self.domain = TagManager.instance.normalize_domain(domain)
  end
end