class Step < ApplicationRecord
  include SearchableModel
  include SearchableByNameModel
  include TinyMceImages
  include ViewableModel

  attr_accessor :skip_position_adjust # to be used in bulk deletion

  enum assets_view_mode: { thumbnail: 0, list: 1, inline: 2 }

  auto_strip_attributes :name, :description, nullify: false
  validates :name,
            presence: true,
            length: { maximum: Constants::NAME_MAX_LENGTH }
  validates :description, length: { maximum: Constants::RICH_TEXT_MAX_LENGTH }
  validates :position, presence: true
  validates :completed, inclusion: { in: [true, false] }
  validates :user, :protocol, presence: true
  validates :completed_on, presence: true, if: proc { |s| s.completed? }
  validates :position, uniqueness: { scope: :protocol }, if: :position_changed?

  before_validation :set_completed_on, if: :completed_changed?
  before_save :set_last_modified_by
  before_destroy :cascade_before_destroy
  after_destroy :adjust_positions_after_destroy, unless: -> { skip_position_adjust }

  # conditional touch excluding step completion updates
  after_destroy :touch_protocol
  after_save :touch_protocol
  after_touch :touch_protocol

  belongs_to :user, inverse_of: :steps
  belongs_to :last_modified_by, foreign_key: 'last_modified_by_id', class_name: 'User', optional: true
  belongs_to :protocol, inverse_of: :steps
  delegate :team, to: :protocol
  has_many :step_orderable_elements, inverse_of: :step, dependent: :destroy
  has_many :checklists, inverse_of: :step, dependent: :destroy
  has_many :step_comments, foreign_key: :associated_id, dependent: :destroy
  has_many :step_texts, inverse_of: :step, dependent: :destroy
  has_many :step_assets, inverse_of: :step, dependent: :destroy
  has_many :assets, through: :step_assets
  has_many :step_tables, inverse_of: :step, dependent: :destroy
  has_many :tables, through: :step_tables
  has_many :report_elements, inverse_of: :step, dependent: :destroy

  accepts_nested_attributes_for :checklists,
                                reject_if: :all_blank,
                                allow_destroy: true
  accepts_nested_attributes_for :assets,
                                reject_if: :all_blank,
                                allow_destroy: true
  accepts_nested_attributes_for :tables,
                                reject_if: proc { |attributes|
                                  attributes['contents'].blank?
                                },
                                allow_destroy: true

  scope :in_order, -> { order(position: :asc) }
  scope :desc_order, -> { order(position: :desc) }

  def self.search(user,
                  include_archived,
                  query = nil,
                  page = 1,
                  _current_team = nil,
                  options = {})
    protocol_ids = Protocol.search(user, include_archived, nil, Constants::SEARCH_NO_LIMIT)
                           .pluck(:id)

    new_query = Step.distinct
                    .left_outer_joins(:step_texts)
                    .where(steps: { protocol_id: protocol_ids })
                    .where_attributes_like(['steps.name', 'step_texts.text'], query, options)

    # Show all results if needed
    if page == Constants::SEARCH_NO_LIMIT
      new_query
    else
      new_query.limit(Constants::SEARCH_LIMIT).offset((page - 1) * Constants::SEARCH_LIMIT)
    end
  end

  def self.filter_by_teams(teams = [])
    return self if teams.blank?

    joins(protocol: { my_module: { experiment: :project } })
      .where(protocol: { my_modules: { experiments: { projects: { team: teams } } } })
  end

  def default_view_state
    { 'assets' => { 'sort' => 'new' } }
  end

  def validate_view_state(view_state)
    unless %w(new old atoz ztoa).include?(view_state.state.dig('assets', 'sort'))
      view_state.errors.add(:state, :wrong_state)
    end
  end

  def self.viewable_by_user(user, teams)
    joins(:protocol).where(protocol: { my_module: MyModule.viewable_by_user(user, teams) })
  end

  def can_destroy?
    !assets.map(&:locked?).any?
  end

  def my_module
    protocol.present? ? protocol.my_module : nil
  end

  def position_plus_one
    position + 1
  end

  def last_comments(last_id = 1, per_page = Constants::COMMENTS_SEARCH_LIMIT)
    last_id = Constants::INFINITY if last_id <= 1
    comments = StepComment.joins(:step)
                          .where(steps: { id: id })
                          .where('comments.id <  ?', last_id)
                          .order(created_at: :desc)
                          .limit(per_page)
    StepComment.from(comments, :comments).order(created_at: :asc)
  end

  def space_taken
    st = 0
    assets.each do |asset|
      st += asset.estimated_size
    end
    st
  end

  def comments
    step_comments
  end

  def description_step_text
    step_texts.order(created_at: :asc).first
  end

  def duplicate(protocol, user, step_position: nil, step_name: nil)
    ActiveRecord::Base.transaction do
      assets_to_clone = []

      new_step = protocol.steps.new(
        name: step_name || name,
        position: step_position || protocol.steps.length,
        completed: false,
        user: user
      )
      new_step.save!

      # Copy texts
      step_texts.each do |step_text|
        step_text.duplicate(new_step, step_text.step_orderable_element.position)
      end

      # Copy checklists
      checklists.asc.each do |checklist|
        checklist.duplicate(new_step, user, checklist.step_orderable_element.position)
      end

      # "Shallow" Copy assets
      assets.each do |asset|
        new_asset = asset.dup
        new_asset.save!
        new_step.assets << new_asset
        assets_to_clone << [asset.id, new_asset.id]
      end

      # Copy tables
      tables.each do |table|
        table.duplicate(new_step, user, table.step_table.step_orderable_element.position)
      end

      # Call clone helper
      Protocol.delay(queue: :assets).deep_clone_assets(assets_to_clone)

      new_step
    end
  end

  def normalize_elements_position
    step_orderable_elements.order(:position).each_with_index do |element, index|
      element.update!(position: index) unless element.position == index
    end
  end

  private

  def touch_protocol
    # if only step completion attributes were changed, do not touch protocol
    return if saved_changes.keys.sort == %w(completed completed_on updated_at)

    # rubocop:disable Rails/SkipsModelValidations
    protocol.update(last_modified_by: last_modified_by) if last_modified_by
    protocol.touch
    # rubocop:enable Rails/SkipsModelValidations
  end

  def adjust_positions_after_destroy
    re_index_following_steps
    protocol.steps.where('position > ?', position).order(:position).each do |step|
      step.update!(position: step.position - 1)
    end
  end

  def re_index_following_steps
    steps = protocol.steps.where(position: position..).order(:position).where.not(id: id)
    i = position
    steps.each do |step|
      i += 1
      step.position = i
    end

    steps.reverse_each do |step|
      step.save! if step.position_changed?
    end
  end

  def cascade_before_destroy
    assets.each(&:destroy)
    tables.each(&:destroy)
  end

  def set_completed_on
    return if completed? && completed_on.present?

    self.completed_on = completed? ? DateTime.now : nil
  end

  def set_last_modified_by
    self.last_modified_by_id ||= user_id
  end
end