class User < ApplicationRecord
  COLORS = %w[#e67e22 #2980b9 #27ae60 #8e44ad #c0392b #16a085 #d35400 #2c3e50].freeze

  has_many :sessions, dependent: :destroy
  has_many :owned_documents, class_name: "Document", foreign_key: :owner_id, dependent: :destroy, inverse_of: :owner
  has_many :document_memberships, dependent: :destroy
  has_many :shared_documents, through: :document_memberships, source: :document

  normalizes :email, with: ->(e) { e.strip.downcase }
  validates :email, presence: true, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP }
  validates :display_name, length: { maximum: 80 }

  before_create { self.color ||= COLORS.sample }

  # Name shown to others (share dialog, lock holder, later: cursors).
  def name
    display_name.presence || email.split("@").first
  end

  # Documents this user owns or has been given access to.
  def accessible_documents
    Document.where(owner_id: id).or(Document.where(id: document_memberships.select(:document_id)))
  end

  def as_json(*)
    { id:, email:, name:, display_name:, color: }
  end
end