# frozen_string_literal: true

#
# Copyright (C) 2013 - present Instructure, Inc.
#
# This file is part of Canvas.
#
# Canvas is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, version 3 of the License.
#
# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.

class OverrideListPresenter
  attr_reader :assignment, :user

  include TextHelper

  def initialize(assignment = nil, user = nil)
    @user = user
    if assignment.present?
      @assignment = AssignmentOverrideApplicator.assignment_overridden_for(assignment, user)
    end
  end

  def lock_at(due_date)
    formatted_date_string(:lock_at, due_date)
  end

  def unlock_at(due_date)
    formatted_date_string(:unlock_at, due_date)
  end

  def due_at(due_date)
    formatted_date_string(:due_at, due_date)
  end

  def due_for(due_date)
    if adhoc_current_override_count_hash.key?(due_date[:id])
      return AssignmentOverride.title_from_student_count(adhoc_current_override_count_hash[due_date[:id]])
    elsif due_date[:title]
      return due_date[:title]
    end

    multiple_due_dates? ? I18n.t("overrides.everyone_else", "Everyone else") : I18n.t("overrides.everyone", "Everyone")
  end

  def formatted_date_string(date_field, date_hash = {})
    date = date_hash[date_field]
    if date.present? && CanvasTime.is_fancy_midnight?(date_hash[date_field]) &&
       date_field == :due_at
      date_string(date, :no_words)
    else
      date.present? ? datetime_string(date) : "-"
    end
  end

  def adhoc_current_override_count_hash
    return @adhoc_current_override_count_hash if defined?(@adhoc_current_override_count_hash)

    @adhoc_current_override_count_hash = if assignment
                                           current_users = assignment.context.enrollments.current_and_invited.select(:user_id).distinct
                                           assignment.assignment_override_students.where(user_id: current_users).group(:assignment_override_id).size
                                         else
                                           {}
                                         end
  end

  # Public: Determine if multiple due dates are visible to user.
  #
  # Returns a boolean
  def multiple_due_dates?
    !!assignment.try(:has_active_overrides?)
  end

  # Public: Return all due dates visible to user, filtering out assignment info
  #   if it isn't needed (e.g. if all sections have overrides).
  #
  # Returns an array of due date hashes.
  def visible_due_dates
    return [] unless assignment

    assignment.dates_hash_visible_to(user).each do |due_date|
      due_date[:raw] = due_date.dup
      due_date[:lock_at] = lock_at due_date
      due_date[:unlock_at] = unlock_at due_date
      due_date[:due_at] = due_at due_date
      due_date[:due_for] = due_for due_date
    end
  end
end