module NotesHelper
  # Helps to distinguish e.g. commit notes in mr notes list
  def note_for_main_target?(note)
    @noteable.class.name == note.noteable_type && !note.diff_note?
  end

  def note_target_fields(note)
    if note.noteable
      hidden_field_tag(:target_type, note.noteable.class.name.underscore) +
        hidden_field_tag(:target_id, note.noteable.id)
    end
  end

  def note_editable?(note)
    note.editable? && can?(current_user, :admin_note, note)
  end

  def noteable_json(noteable)
    {
      id: noteable.id,
      class: noteable.class.name,
      resources: noteable.class.table_name,
      project_id: noteable.project.id,
    }.to_json
  end

  def diff_view_data
    return {} unless @comments_target

    @comments_target.slice(:noteable_id, :noteable_type, :commit_id)
  end

  def diff_view_line_data(line_code, position, line_type)
    return if @diff_notes_disabled

    use_legacy_diff_note = @use_legacy_diff_notes
    # If the controller doesn't force the use of legacy diff notes, we
    # determine this on a line-by-line basis by seeing if there already exist
    # active legacy diff notes at this line, in which case newly created notes
    # will use the legacy technology as well.
    # We do this because the discussion_id values of legacy and "new" diff
    # notes, which are used to group notes on the merge request discussion tab,
    # are incompatible.
    # If we didn't, diff notes that would show for the same line on the changes
    # tab, would show in different discussions on the discussion tab.
    use_legacy_diff_note ||= begin
      line_diff_notes = @grouped_diff_notes[line_code]
      line_diff_notes && line_diff_notes.any?(&:legacy_diff_note?)
    end

    data = {
      line_code: line_code,
      line_type: line_type,
    }

    if use_legacy_diff_note
      discussion_id = LegacyDiffNote.build_discussion_id(
        @comments_target[:noteable_type],
        @comments_target[:noteable_id] || @comments_target[:commit_id],
        line_code
      )

      data.merge!(
        note_type: LegacyDiffNote.name,
        discussion_id: discussion_id
      )
    else
      discussion_id = DiffNote.build_discussion_id(
        @comments_target[:noteable_type],
        @comments_target[:noteable_id] || @comments_target[:commit_id],
        position
      )

      data.merge!(
        position: position.to_json,
        note_type: DiffNote.name,
        discussion_id: discussion_id
      )
    end

    data
  end

  def link_to_reply_discussion(note, line_type = nil)
    return unless current_user

    data = {
      noteable_type: note.noteable_type,
      noteable_id:   note.noteable_id,
      commit_id:     note.commit_id,
      discussion_id: note.discussion_id,
      line_type:     line_type
    }

    if note.diff_note?
      data[:note_type] = note.type

      data.merge!(note.diff_attributes)
    end

    content_tag(:div, class: "discussion-reply-holder") do
      button_tag 'Reply...', class: 'btn btn-text-field js-discussion-reply-button',
                             data: data, title: 'Add a reply'
    end
  end

  def note_max_access_for_user(note)
    @max_access_by_user_id ||= Hash.new do |hash, key|
      project = key[:project]
      hash[key] = project.team.human_max_access(key[:user_id])
    end

    full_key = { project: note.project, user_id: note.author_id }
    @max_access_by_user_id[full_key]
  end

  def diff_note_path(note)
    return unless note.diff_note?

    if note.for_merge_request? && note.active?
      diffs_namespace_project_merge_request_path(note.project.namespace, note.project, note.noteable, anchor: note.line_code)
    elsif note.for_commit?
      namespace_project_commit_path(note.project.namespace, note.project, note.noteable, anchor: note.line_code)
    end
  end
end