module Api
  # The edit lock of a server document: one browser tab edits at a time,
  # everyone else sees the document read-only until the lock is released or
  # expires (Document::LOCK_TTL without a heartbeat).
  class DocumentLocksController < BaseController
    before_action :load_document

    # POST /api/documents/:id/lock -- take or refresh (heartbeat)
    def create
      return render(json: { lock: { mine: false, holder_name: nil } }) unless Document.role_at_least?(@role, :editor)
      mine = @doc.acquire_lock!(lock_holder, holder_name)
      render json: { lock: { mine:, holder_name: (@doc.lock_holder_name unless mine) } }
    end

    # DELETE /api/documents/:id/lock
    def destroy
      @doc.release_lock!(lock_holder)
      head :no_content
    end

    private

    def load_document
      @doc = Document.find(params[:document_id])
      @role = @doc.role_for(user: Current.user, token: share_token)
      raise ActiveRecord::RecordNotFound unless @role
    end
  end
end