educoder/app/controllers/poll_votes_controller.rb

class PollVotesController < ApplicationController
  #在开始回答和提交问卷的时候，已经做了判断用户的身份权限
  before_action :require_login
  before_action :get_poll_question
  before_action :check_answer_in_question,only: [:create]
  before_action :check_multi_answers


  def create  #每一次答案的点击，请求一次
    ActiveRecord::Base.transaction do
      begin
        question_votes = @poll_question.poll_votes
        question_type = @poll_question.question_type
        question_answer_id = params[:poll_answer_id] ? params[:poll_answer_id] : nil #该答案的id
        question_answer_text = params[:vote_text].present? ? params[:vote_text] : nil    #其他选项的内容
        user_votes = question_votes.find_current_vote("user_id",current_user.id) #当前用户的答案，可能有多个
        # 当前用户的当前答案，如果已存在，当再次点击的时候，取消答案，即删除该答案
        current_vote_text = nil

        if user_votes.find_vote_text.present?
          current_vote_text = user_votes.find_vote_text.first
        end

          vote_answer_params = {
              :user_id => current_user.id,
              :poll_question_id => @poll_question.id,
              :poll_answer_id => question_answer_id,
              :vote_text => question_answer_text
          }
        #begin
        if question_type == 1
          if user_votes.present?  #用户曾经回答过的，答案选择不一样，否则新建
            current_user_answer = user_votes.first
            if current_user_answer.poll_answer_id != question_answer_id   #如果说更换了答案，则以前的答案删除，并新建记录
              current_user_answer.destroy
              PollVote.create(vote_answer_params)
            else
              if question_answer_text.present?
                current_user_answer.update_attribute("vote_text", question_answer_text)
              end
            end
          else
            PollVote.create(vote_answer_params)
          end
        elsif question_type == 2   #多选题的话，答案应该是1个以上
          question_answer_ids = params[:poll_answer_id] ? params[:poll_answer_id] : [] #该答案的id
          if question_answer_ids.present?
            if question_answer_text.present?   #有文字输入，但是不存在其他选项的
              ques_vote_id = question_answer_ids.map(&:to_i).max
              if current_vote_text.present?   #已有其他输入文字的选项
                current_vote_text.update_attribute("vote_text", question_answer_text)
              else
                answer_option = {
                    :user_id => current_user.id,
                    :poll_question_id => @poll_question.id,
                    :poll_answer_id => ques_vote_id,
                    :vote_text => question_answer_text
                }
                PollVote.create(answer_option)
              end
            end

            ea_ids = user_votes.pluck(:poll_answer_id)
            common_answer_ids = question_answer_ids & ea_ids   #已经存在的试卷选项id
            new_ids = question_answer_ids - common_answer_ids   # 新增的id
            old_ids = ea_ids - common_answer_ids  #没有选择的，则删掉
            if new_ids.size > 0
              new_ids.each do |e|
                answer_option = {
                    :user_id => current_user.id,
                    :poll_question_id => @poll_question.id,
                    :poll_answer_id => e,
                    :vote_text => nil
                }
                ex_a = PollVote.new(answer_option)
                ex_a.save!
              end
            end
            if old_ids.size > 0
              ea_answer = user_votes.find_current_vote("poll_answer_id",old_ids)
              ea_answer.destroy_all
            end
          else
            user_votes.destroy_all
          end
        else   #主观题的输入
          if current_vote_text.present?
            if question_answer_text.present?
              user_votes.first.update_attribute("vote_text", question_answer_text)
            else
              user_votes.destroy_all
            end
          else
            PollVote.create(vote_answer_params)
          end
        end
        @current_question_number = @poll_question.question_number
        @current_question_necessary = @poll_question.is_necessary
        #问答记录存在，且有值，才会有返回值。
        @current_question_status = 0
        if user_votes.present?
          vote_answer_id = user_votes.pluck(:poll_answer_id).reject(&:blank?).size
          vote_text_count = user_votes.pluck(:vote_text).reject(&:blank?).size
          if vote_text_count > 0 || vote_answer_id > 0
            @current_question_status = 1
          end
        end
      rescue Exception => e
        uid_logger_error(e.message)
        tip_exception("页面调用失败！")
        raise ActiveRecord::Rollback
      end
    end
  end


  private

  def get_poll_question
    @poll_question = PollQuestion.find_by_id(params[:poll_question_id])
    if @poll_question.blank?
      normal_status(-1,"问卷试题不存在！")
    else
      @poll = @poll_question.poll
      @course = @poll.course
      if @poll.blank?
        normal_status(-1,"问卷不存在！")
      elsif @course.blank?
        normal_status(-1,"课堂不存在！")
      end
    end

  end

  def check_answer_in_question
    poll_answer_ids = @poll_question.poll_answers.pluck(:id)
    if @poll_question.question_type == 1   #单选题/多选题
      unless (params[:poll_answer_id].present? && poll_answer_ids.include?(params[:poll_answer_id].to_i)) || (params[:poll_answer_id].blank? && params[:vote_text].present?)
        normal_status(-1, "答案ID错误！")
      end
    end
  end

  def check_multi_answers
    if @poll_question.question_type == 2
      user_vote_count = params[:poll_answer_id].size
      if @poll_question.max_choices.present?
        question_max_choices = @poll_question.max_choices
      else
        question_max_choices = 0
      end
      if question_max_choices > 0 && user_vote_count > question_max_choices
        normal_status(-1,"多选题答案超过最大限制！")
      end
    end
  end
end