diff --git a/app/controllers/exercise_controller.rb b/app/controllers/exercise_controller.rb
index 444446ef4..a3e4f89c3 100644
--- a/app/controllers/exercise_controller.rb
+++ b/app/controllers/exercise_controller.rb
@@ -1,681 +1,681 @@
-class ExerciseController < ApplicationController
-  layout "base_courses"
-
-  before_filter :find_exercise_and_course, :only => [:create_exercise_question, :edit, :update, :show, :destroy,
-                                                        :commit_exercise, :commit_answer,:publish_exercise,:republish_exercise,
-                                                        :show_student_result,:student_exercise_list]
-  before_filter :find_course, :only => [:index,:new,:create]
-  include ExerciseHelper
-
-  def index
-    publish_exercises = Exercise.where("publish_time is not null and exercise_status = 1 and publish_time <=?",Time.now)
-    publish_exercises.each do |exercise|
-      exercise.update_column('exercise_status', 2)
-      course = exercise.course
-      course.members.each do |m|
-        exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
-      end
-    end
-
-    if @course.is_public == 0 && !(User.current.member_of_course?(@course)||User.current.admin?)
-      render_403
-      return
-    end
-    remove_invalid_exercise(@course)
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
-    if @is_teacher || User.current.admin?
-      exercises = @course.exercises.order("created_at asc")
-    else
-      exercises = @course.exercises.where("exercise_status <> 1").order("created_at asc")
-    end
-    @exercises = paginateHelper exercises,20 #分页
-    respond_to do |format|
-      format.html
-    end
-  end
-
-  def show
-    publish_exercises = Exercise.where("publish_time is not null and exercise_status = 1 and publish_time <=?",Time.now)
-    publish_exercises.each do |exercise|
-      exercise.update_column('exercise_status', 2)
-      course = exercise.course
-      course.members.each do |m|
-        exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
-      end
-    end
-
-    unless User.current.member_of_course?(@course) || User.current.admin?
-      render_403
-      return
-    end
-    @exercise = Exercise.find params[:id]
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
-    exercise_end = @exercise.end_time > Time.now
-    if @exercise.time == -1
-      @can_edit_excercise = exercise_end
-    else
-      @can_edit_excercise = !has_commit_exercise?(@exercise.id,User.current.id)&& exercise_end
-    end
-    unless @is_teacher
-      @exercise_user = ExerciseUser.where("user_id=? and exercise_id=?", User.current.id, @exercise.id).first
-      if @exercise_user.nil?
-        eu = ExerciseUser.create(:user_id => User.current.id, :exercise_id => @exercise.id, :start_at => Time.now, :status => false)
-        @exercise_user = ExerciseUser.where("user_id=? and exercise_id=?", User.current.id, @exercise.id).first
-      end
-      score = calculate_student_score(@exercise, User.current)
-      @exercise_user.update_attributes(:score => score)
-    end
-    # @percent = get_percent(@exercise,User.current)
-    @exercise_questions = @exercise.exercise_questions
-    respond_to do |format|
-      format.html {render :layout => 'base_courses'}
-    end
-    #end
-  end
-
-  def new
-    option = {
-        :exercise_name => "",
-        :course_id => @course.id,
-        :exercise_status => 1,
-        :user_id => User.current.id,
-        :time => "",
-        :end_time => "",
-        :publish_time => "",
-        :exercise_description => "",
-        :show_result => 1
-    }
-    @exercise = Exercise.create option
-    if @exercise
-      redirect_to edit_exercise_url @exercise.id
-    end
-  end
-
-  def create
-    if params[:exercise]
-      exercise = Exercise.find(params[:exercise_id]) if params[:exercise_id]
-      exercise ||= Exercise.new
-      exercise.exercise_name = params[:exercise][:exercise_name]
-      exercise.exercise_description = params[:exercise][:exercise_description]
-      exercise.end_time = Time.at(params[:exercise][:end_time].to_time.to_i + 16*60*60 -1)
-      exercise.publish_time = params[:exercise][:publish_time]
-      exercise.user_id = User.current.id
-      exercise.time = params[:exercise][:time]
-      exercise.course_id = params[:course_id]
-      exercise.exercise_status = 1
-      if exercise.save
-        @exercise = exercise
-        respond_to do |format|
-          format.js
-        end
-      end
-    end
-  end
-
-  def edit
-    respond_to do |format|
-      format.html{render :layout => 'base_courses'}
-  end
-  end
-
-  def update
-    @exercise.exercise_name = params[:exercise][:exercise_name]
-    @exercise.exercise_description = params[:exercise][:exercise_description]
-    @exercise.time =  params[:exercise][:time].blank? ? -1 : params[:exercise][:time]
-    @exercise.end_time = Time.at(params[:exercise][:end_time].to_time.to_i + 16*60*60 -1)
-    @exercise.publish_time = params[:exercise][:publish_time]
-    @exercise.show_result = params[:exercise][:show_result].blank? ? 1 : params[:exercise][:show_result]
-    if @exercise.save
-      respond_to do |format|
-        format.js
-      end
-    else
-      render_404
-      end
-  end
-
-  def destroy
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
-    if @exercise && @exercise.destroy
-      if @is_teacher
-        exercises = Exercise.where("course_id =?", @course.id)
-      else
-        exercises = Exercise.where("course_id =? and exercise_status =?", @course.id, 2)
-      end
-      @exercises = paginateHelper exercises,20 #分页
-      respond_to do |format|
-        format.js
-      end
-    end
-  end
-
-  # 统计结果
-  def statistics_result
-    @exercise = Exercise.find(params[:id])
-    exercise_questions = @exercise.exercise_questions
-    @exercise_questions = paginateHelper exercise_questions, 5
-    respond_to do |format|
-      format.html{render :layout => 'base_courses'}
-    end
-  end
-
-  # 添加题目
-  # question_type 1：单选 2：多选 3：填空题
-  def create_exercise_question
-    question_title = params[:question_title].nil? || params[:question_title].empty? ? l(:label_enter_single_title) : params[:question_title]
-    option = {
-        :question_title => question_title,
-        :question_type => params[:question_type] || 1,
-        :question_number => params[:question_type] == "1"? @exercise.exercise_questions.where("question_type = 1").count + 1 :
-                              (params[:question_type] == "2" ? (@exercise.exercise_questions.where("question_type = 2").count + 1) :
-                              @exercise.exercise_questions.where("question_type = 3").count + 1),
-        :question_score => params[:question_score]
-    }
-    @exercise_questions = @exercise.exercise_questions.new option
-    # params[:question_answer] 题目选项
-    if params[:question_answer]
-      for i in 1..params[:question_answer].count
-        answer = (params[:question_answer].values[i-1].nil? || params[:question_answer].values[i-1].empty?) ? l(:label_new_answer) : params[:question_answer].values[i-1]
-        question_option = {
-            :choice_position => i,
-            :choice_text => answer
-        }
-        @exercise_questions.exercise_choices.new question_option
-      end
-    end
-    # 如果是插入的话，那么从插入的这个id以后的question_num都将要+1
-    if params[:quest_id]
-      @is_insert = true
-      if @exercise_questions.question_type == 1
-        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 1).update_all(" question_number = question_number + 1")
-        #@exercise.exercise_questions.where("question_number > #{params[:quest_num].to_i} and question_type == 1").update_all(" question_number = question_number + 1")
-      elsif @exercise_questions.question_type == 2
-        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 2).update_all(" question_number = question_number + 1")
-      else
-        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 3).update_all(" question_number = question_number + 1")
-      end
-      # @exercise_question_num = params[:quest_num].to_i
-      @exercise_questions.question_number = params[:quest_num].to_i + 1
-    end
-    if @exercise_questions.save
-      # params[:exercise_choice] 标准答案参数
-      # 问答题标准答案有三个，单独处理
-      if @exercise_questions.question_type == 3
-        for i in 1..params[:exercise_choice].count
-          standart_answer = ExerciseStandardAnswer.new
-          standart_answer.exercise_question_id =  @exercise_questions.id
-          standart_answer.answer_text = params[:exercise_choice].values[i-1]
-          standart_answer.save
-        end
-      else
-        standart_answer = ExerciseStandardAnswer.new
-        standart_answer.exercise_question_id =  @exercise_questions.id
-        if  @exercise_questions.question_type == 1
-          standart_answer.exercise_choice_id = sigle_selection_standard_answer(params[:exercise_choice])
-        else
-          standart_answer.exercise_choice_id = multiselect_standard_answer(params[:exercise_choice])
-        end
-        standart_answer.save
-      end
-      respond_to do |format|
-        format.js
-      end
-    end
-
-  end
-
-  # 修改题目
-  # params[:exercise_question]  The id of exercise_question
-  # params[:question_answer]  eg:A、B、C选项
-  def update_exercise_question
-    @exercise_question = ExerciseQuestion.find params[:exercise_question]
-    @exercise_question.question_title = params[:question_title].nil? || params[:question_title].empty? ? l(:label_enter_single_title) : params[:question_title]
-    @exercise_question.question_score = params[:question_score]
-    # 处理选项:如果选了某个选项，那么则要删除之前的选项
-    if params[:question_answer]
-      @exercise_question.exercise_choices.each do |answer|
-        answer.destroy unless params[:question_answer].keys.include? answer.id.to_s
-      end
-      for i in 1..params[:question_answer].count
-        question = @exercise_question.exercise_choices.find_by_id params[:question_answer].keys[i-1]
-        answer = (params[:question_answer].values[i-1].nil? || params[:question_answer].values[i-1].empty?) ? l(:label_new_answer) : params[:question_answer].values[i-1]
-        if question
-          question.choice_position = i
-          question.choice_text = answer
-          question.save
-        else
-          question_option = {
-              :choice_position => i,
-              :choice_text => answer
-          }
-          @exercise_question.exercise_choices.new question_option
-        end
-      end
-    end
-    # 更新标准答案
-    if params[:exercise_choice]
-      if @exercise_question.question_type == 3
-        # 删除不合理的选项
-        @exercise_question.exercise_standard_answers.each do |answer|
-          answer.destroy unless params[:exercise_choice].keys.include? answer.id.to_s
-        end
-        for i in 1..params[:exercise_choice].count
-          # 找到对应的标准答案
-          question_standart = @exercise_question.exercise_standard_answers.find_by_id params[:exercise_choice].keys[i-1]
-          # 标准答案值
-          answer_standart = (params[:exercise_choice].values[i-1].nil? || params[:exercise_choice].values[i-1].empty?) ? l(:label_new_answer) : params[:exercise_choice].values[i-1]
-          if question_standart
-            question_standart.answer_text = answer_standart
-            question_standart.save
-          else
-            standart_answer_option = {
-                :answer_text => answer_standart
-            }
-            @exercise_question.exercise_standard_answers.new standart_answer_option
-          end
-        end
-      else
-        answer_standart = @exercise_question.exercise_standard_answers.first
-        answer_standart.exercise_choice_id = @exercise_question.question_type == 1 ? sigle_selection_standard_answer(params[:exercise_choice]) : multiselect_standard_answer(params[:exercise_choice])
-        answer_standart.save
-      end
-      @exercise_question.save
-      respond_to do |format|
-        format.js
-      end
-    end
-  end
-
-  # 删除题目
-  def delete_exercise_question
-    @exercise_question = ExerciseQuestion.find params[:exercise_question]
-    @exercise = @exercise_question.exercise
-
-    if @exercise_question.question_type == 1
-      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 1).update_all(" question_number = question_number - 1")
-      #@exercise.exercise_questions.where("question_number > #{params[:quest_num].to_i} and question_type == 1").update_all(" question_number = question_number + 1")
-    elsif @exercise_question.question_type == 2
-      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 2).update_all(" question_number = question_number - 1")
-    else
-      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 3).update_all(" question_number = question_number - 1")
-    end
-    # @exercise_question_num = params[:quest_num].to_i
-    # @exercise_questions.question_number = params[:quest_num].to_i - 1
-    #
-    # exercise_questions = @exercise.exercise_questions.where("question_number > #{@exercise_question.question_number}")
-    # exercise_questions.each do |question|
-    #   question.question_number -= 1
-    #   question.save
-    # end
-    if @exercise_question && @exercise_question.destroy
-      respond_to do |format|
-        format.js
-      end
-    end
-  end
-
-  # 发布试卷
-  def publish_exercise
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
-    @index = params[:index]
-    @exercise.exercise_status = 2
-    @exercise.publish_time = Time.now
-    if @exercise.save
-      @exercise.course.members.each do |m|
-         @exercise.course_messages << CourseMessage.create(:user_id =>m.user_id, :course_id => @exercise.course.id, :viewed => false,:status=>2)
-      end
-      #redirect_to exercise_index_url(:course_id=> @course.id)
-      respond_to do |format|
-        format.js
-      end
-    end
-  end
-
-  # 重新发布试卷
-  # 重新发布的时候会删除所有的答题
-  def republish_exercise
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
-    @index = params[:index]
-    @exercise.exercise_questions.each do |exercise_question|
-      exercise_question.exercise_answers.destroy_all
-    end
-    @exercise.course_messages.destroy_all
-    @exercise.exercise_users.destroy_all
-    @exercise.exercise_status = 1
-    @exercise.publish_time = nil
-    @exercise.save
-    respond_to do |format|
-      format.js
-    end
-  end
-
-  def student_exercise_list
-=begin
-    if @exercise.end_time <= Time.now
-      @course.student.each do |student|
-        if ExerciseUser.where("user_id = ? && exercise_id = ?",student.student_id,@exercise.id).empty?
-          ExerciseUser.create(:user_id => student.student_id, :exercise_id => @exercise.id, :start_at => @exercise.end_time, :status => true,:score=>0)
-        end
-
-        s_score = calculate_student_score(@exercise, student.student)
-        exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", student.student_id, @exercise.id).first
-        exercise_user.update_attributes(:score => s_score)
-      end
-    end
-=end
-    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
-    @all_exercises = @course.exercises.where("exercise_status > 1").order("created_at desc")
-    @exercise_count = @exercise.exercise_users.where('score is not NULL').count
-    if @is_teacher || (!@exercise.exercise_users.where(:user_id => User.current.id).empty? && @exercise.end_time <= Time.now)
-      @exercise_users_list = @exercise.exercise_users.where('score is not NULL')
-      @show_all = true;
-    elsif !@exercise.exercise_users.where(:user_id => User.current.id).empty? && @exercise.end_time > Time.now
-      @exercise_users_list = @exercise.exercise_users.where("user_id = ? and score is not NULL",User.current.id)
-    else
-      @exercise_users_list = []
-    end
-    respond_to do |format|
-      format.html
-    end
-  end
-
-  # 学生提交答卷，选中答案的过程中提交
-  def commit_answer
-    eq = ExerciseQuestion.find(params[:exercise_question_id])
-    # 已提交过的且是限时的则不允许答题
-    if (has_commit_exercise?(@exercise.id,User.current.id) && (!User.current.admin?) && @exercise.time != -1) || @exercise.end_time < Time.now
-      render :json => {:text => "failure"}
-      return
-    end
-    if eq.question_type == 1
-      # 单选题
-      ea = ExerciseAnswer.find_by_exercise_question_id_and_user_id(params[:exercise_question_id],User.current.id)
-      if ea.nil?
-        # 尚未答该题，添加答案
-        ea = ExerciseAnswer.new
-        ea.user_id = User.current.id
-        ea.exercise_question_id = params[:exercise_question_id]
-      end
-      #修改该题对应答案
-      ea.exercise_choice_id = params[:exercise_choice_id]
-      if ea.save
-        # 保存成功返回成功信息及当前以答题百分比
-        uncomplete_question = get_uncomplete_question(@exercise, User.current)
-        if uncomplete_question.count < 1
-          complete = 1;
-        else
-          complete = 0;
-        end
-        @percent = get_percent(@exercise,User.current)
-        render :json => {:text => "ok" ,:complete => complete,:percent => format("%.2f" ,@percent)}
-      else
-        #返回失败信息
-        render :json => {:text => "failure"}
-      end
-    elsif eq.question_type == 2
-      #多选题
-      ea = ExerciseAnswer.find_by_exercise_choice_id_and_user_id(params[:exercise_choice_id],User.current.id)
-      if ea.nil?
-        #尚未答该题，添加答案
-        ea = ExerciseAnswer.new
-        ea.user_id = User.current.id
-        ea.exercise_question_id = params[:exercise_question_id]
-        ea.exercise_choice_id = params[:exercise_choice_id]
-        if ea.save
-          uncomplete_question = get_uncomplete_question(@exercise, User.current)
-          if uncomplete_question.count < 1
-            complete = 1;
-          else
-            complete = 0;
-          end
-          @percent = get_percent(@exercise,User.current)
-          render :json => {:text => "ok",:complete => complete,:percent => format("%.2f" ,@percent)}
-        else
-          render :json => {:text => "failure"}
-        end
-      else
-        #pv不为空，则当前选项之前已被选择，再次点击则是不再选择该项，故删除该答案
-        if ea.delete
-          @percent = get_percent(@exercise, User.current)
-          render :json => {:text => "false" ,:percent => format("%.2f" , @percent)}
-        else
-          render :json => {:text => "failure"}
-        end
-      end
-    elsif eq.question_type == 3
-      #单行文本，多行文本题
-      ea = ExerciseAnswer.find_by_exercise_question_id_and_user_id(params[:exercise_question_id], User.current.id)
-      if ea.nil?
-        # ea为空之前尚未答题，添加答案
-        if params[:answer_text].nil? || params[:answer_text].blank?
-          #用户提交空答案，视作不作答
-          @percent = get_percent(@exercise,User.current)
-          render :json => {:text => "",:percent => format("%.2f", @percent)}
-        else
-          #添加答案
-          ea = ExerciseAnswer.new
-          ea.user_id = User.current.id
-          ea.exercise_question_id = params[:exercise_question_id]
-          ea.answer_text = params[:answer_text]
-          if ea.save
-            uncomplete_question = get_uncomplete_question(@exercise, User.current)
-            if uncomplete_question.count < 1
-              complete = 1;
-            else
-              complete = 0;
-            end
-            @percent = get_percent(@exercise,User.current)
-            render :json => {:text => ea.answer_text,:complete => complete,:percent => format("%.2f",@percent)}
-          else
-            render :json => {:text => "failure"}
-          end
-        end
-      else
-        # ea不为空说明用户之前已作答
-        if params[:answer_text].nil? || params[:answer_text].blank?
-          # 用户提交空答案，视为删除答案
-          if ea.delete
-            @percent = get_percent(@exercise,User.current)
-            render :json => {:text => "",:percent => format("%.2f", @percent)}
-          else
-            render :json => {:text => "failure"}
-          end
-        else
-          #用户修改答案
-          ea.answer_text = params[:answer_text]
-          if ea.save
-            @percent = get_percent(@exercise,User.current)
-            render :json => {:text => ea.answer_text,:percent => format("%.2f", @percent)}
-          else
-            render :json => {:text => "failure"}
-          end
-        end
-      end
-
-    else
-      render :json => {:text => "failure"}
-    end
-  end
-
-  # 提交问卷
-  def commit_exercise
-    # 老师不需要提交
-    if User.current.allowed_to?(:as_teacher,@course)
-      if @exercise.publish_time.nil?
-        @exercise.update_attributes(:show_result => params[:show_result])
-        @exercise.update_attributes(:exercise_status => 2)
-        @exercise.update_attributes(:publish_time => Time.now)
-        course = @exercise.course
-        course.members.each do |m|
-          @exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
-        end
-        redirect_to exercise_url(@exercise)
-        return
-      elsif @exercise.publish_time > Time.now
-        @exercise.update_attributes(:show_result => params[:show_result])
-        redirect_to exercise_url(@exercise)
-        return
-      end
-      @exercise.update_attributes(:show_result => params[:show_result])
-      redirect_to exercise_url(@exercise)
-      # REDO: 提示提交成功
-    else
-      # 更新提交状态
-      cur_exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", User.current, @exercise.id).first
-      cur_exercise_user.update_attributes(:status => 1)
-      # 答题过程中需要统计完成量
-      @uncomplete_question = get_uncomplete_question(@exercise, User.current)
-      # 获取改学生的考试得分
-      @score = calculate_student_score(@exercise, User.current)
-      # @score = 100
-      if @uncomplete_question.count < 1
-        # 查看是否有已提交记录
-        cur_exercise_user.score = @score
-        if cur_exercise_user.save
-        #redirect_to poll_index_path(:polls_group_id => @course.id,:polls_type => 'Course')
-          @status = 0 #提交成功
-        else
-          @status = 2 #未知错误
-        end
-      else
-        @status = 1 #有未做得必答题
-      end
-      @save = params[:save].to_i if params[:save]
-      respond_to do |format|
-        format.js
-      end
-    end
-  end
-
-  #查看学生的答卷情况
-  def show_student_result
-    @user = User.find params[:user_id]
-    @can_edit_excercise = false
-    @exercise_questions = @exercise.exercise_questions
-    score = calculate_student_score(@exercise, @user)
-    eu = get_exercise_user(@exercise.id, @user.id)
-    eu.update_attributes(:score => score)
-    @exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", @user.id, @exercise.id).first
-    respond_to do |format|
-      format.html {render :layout => 'base_courses'}
-    end
-  end
-
-  # 计算学生得分
-  def calculate_student_score(exercise, user)
-    score = 0
-    score1 = 0
-    score2 = 0
-    score3 = 0
-    exercise_qustions = exercise.exercise_questions
-    exercise_qustions.each do |question|
-      answer = get_user_answer(question, user)
-      standard_answer = get_user_standard_answer(question, user)
-      unless answer.empty?
-        # 问答题有多个答案
-        if question.question_type == 3 && !standard_answer.empty?
-          if standard_answer.include?(answer.first.answer_text)
-            score1 = score1+ question.question_score unless question.question_score.nil?
-          end
-        elsif question.question_type == 1 && !standard_answer.nil?
-          if answer.first.exercise_choice.choice_position == standard_answer.exercise_choice_id
-            score2 = score2 + question.question_score unless question.question_score.nil?
-          end
-        elsif question.question_type == 2 && !standard_answer.nil?
-          arr = get_mulscore(question, user)
-          if arr.to_i == standard_answer.exercise_choice_id
-            score3 = score3 + question.question_score unless question.question_score.nil?
-          end
-          # ecs = ExerciseAnswer.where("user_id =? and exercise_question_id =?", user.id, question.id)
-          # arr = []
-          # ecs.each do |ec|
-          #   arr << ec.exercise_choice.choice_position
-          # end
-          # arr.sort
-          # arr = arr.join("")
-          # if arr.to_i == standard_answer.exercise_choice_id
-          #   score3 = score + question.question_score unless question.question_score.nil?
-          # end
-        end
-      end
-    end
-    score = score1 + score2 + score3
-  end
-
-  private
-
-  # ExerciseUser记录用户是否已提交问卷有对应的记录则已提交，没有则新建一个
-  def get_exercise_user exercise_id,user_id
-    eu = ExerciseUser.find_by_exercise_id_and_user_id(exercise_id,user_id)
-    if eu.nil?
-      eu = ExerciseUser.new
-    end
-    eu
-  end
-
-  # 获取当前学生回答问题的答案
-  def get_user_answer(question,user)
-    # user_answer = ExerciseAnswer.where("user_id=? and exercise_question_id=?", user.id, question.id).first
-    user_answer = question.exercise_answers.where("#{ExerciseAnswer.table_name}.user_id = #{user.id}")
-    user_answer
-  end
-
-  # 获取问题的标准答案
-  def get_user_standard_answer(question,user)
-    if question.question_type == 3
-      standard_answer =[]
-      question.exercise_standard_answers.each do |answer|
-        standard_answer << answer.answer_text
-      end
-    else
-      standard_answer = question.exercise_standard_answers.first
-    end
-    standard_answer
-  end
-  # 是否完成了答题
-  def get_complete_question(exercise,user)
-    questions = exercise.exercise_questions
-    complete_question = []
-    questions.each do |question|
-      answers = get_user_answer(question,user)
-      if !(answers.nil? || answers.count < 1)
-        complete_question << question
-      end
-    end
-    complete_question
-  end
-
-  # 获取答题百分比
-  def get_percent exercise,user
-    complete_count = get_complete_question(exercise,user).count
-    if exercise.exercise_questions.count == 0
-      return 0
-    else
-      return (complete_count.to_f / exercise.exercise_questions.count.to_f)*100
-    end
-  end
-
-  def remove_invalid_exercise(course)
-    exercises = course.exercises.where("exercise_name=?","")
-    unless exercises.empty?
-      exercises.each do |exercise|
-        if exercise.exercise_questions.empty?
-          exercise.destroy
-        end
-      end
-    end
-  end
-
-  def find_exercise_and_course
-    @exercise = Exercise.find params[:id]
-    @course = Course.find @exercise.course_id
-  rescue Exception => e
-    render_404
-  end
-
-  def find_course
-    @course = Course.find params[:course_id]
-  rescue Exception => e
-    render_404
-  end
+class ExerciseController < ApplicationController
+  layout "base_courses"
+
+  before_filter :find_exercise_and_course, :only => [:create_exercise_question, :edit, :update, :show, :destroy,
+                                                        :commit_exercise, :commit_answer,:publish_exercise,:republish_exercise,
+                                                        :show_student_result,:student_exercise_list]
+  before_filter :find_course, :only => [:index,:new,:create]
+  include ExerciseHelper
+
+  def index
+    publish_exercises = Exercise.where("publish_time is not null and exercise_status = 1 and publish_time <=?",Time.now)
+    publish_exercises.each do |exercise|
+      exercise.update_column('exercise_status', 2)
+      course = exercise.course
+      course.members.each do |m|
+        exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
+      end
+    end
+
+    if @course.is_public == 0 && !(User.current.member_of_course?(@course)||User.current.admin?)
+      render_403
+      return
+    end
+    remove_invalid_exercise(@course)
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
+    if @is_teacher || User.current.admin?
+      exercises = @course.exercises.order("created_at asc")
+    else
+      exercises = @course.exercises.where("exercise_status <> 1").order("created_at asc")
+    end
+    @exercises = paginateHelper exercises,20 #分页
+    respond_to do |format|
+      format.html
+    end
+  end
+
+  def show
+    publish_exercises = Exercise.where("publish_time is not null and exercise_status = 1 and publish_time <=?",Time.now)
+    publish_exercises.each do |exercise|
+      exercise.update_column('exercise_status', 2)
+      course = exercise.course
+      course.members.each do |m|
+        exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
+      end
+    end
+
+    unless User.current.member_of_course?(@course) || User.current.admin?
+      render_403
+      return
+    end
+    @exercise = Exercise.find params[:id]
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
+    exercise_end = @exercise.end_time > Time.now
+    if @exercise.time == -1
+      @can_edit_excercise = exercise_end
+    else
+      @can_edit_excercise = !has_commit_exercise?(@exercise.id,User.current.id)&& exercise_end
+    end
+    unless @is_teacher
+      @exercise_user = ExerciseUser.where("user_id=? and exercise_id=?", User.current.id, @exercise.id).first
+      if @exercise_user.nil?
+        eu = ExerciseUser.create(:user_id => User.current.id, :exercise_id => @exercise.id, :start_at => Time.now, :status => false)
+        @exercise_user = ExerciseUser.where("user_id=? and exercise_id=?", User.current.id, @exercise.id).first
+      end
+      score = calculate_student_score(@exercise, User.current)
+      @exercise_user.update_attributes(:score => score)
+    end
+    # @percent = get_percent(@exercise,User.current)
+    @exercise_questions = @exercise.exercise_questions
+    respond_to do |format|
+      format.html {render :layout => 'base_courses'}
+    end
+    #end
+  end
+
+  def new
+    option = {
+        :exercise_name => "",
+        :course_id => @course.id,
+        :exercise_status => 1,
+        :user_id => User.current.id,
+        :time => "",
+        :end_time => "",
+        :publish_time => "",
+        :exercise_description => "",
+        :show_result => 1
+    }
+    @exercise = Exercise.create option
+    if @exercise
+      redirect_to edit_exercise_url @exercise.id
+    end
+  end
+
+  def create
+    if params[:exercise]
+      exercise = Exercise.find(params[:exercise_id]) if params[:exercise_id]
+      exercise ||= Exercise.new
+      exercise.exercise_name = params[:exercise][:exercise_name]
+      exercise.exercise_description = params[:exercise][:exercise_description]
+      exercise.end_time = Time.at(params[:exercise][:end_time].to_time.to_i + 16*60*60 -1)
+      exercise.publish_time = params[:exercise][:publish_time]
+      exercise.user_id = User.current.id
+      exercise.time = params[:exercise][:time]
+      exercise.course_id = params[:course_id]
+      exercise.exercise_status = 1
+      if exercise.save
+        @exercise = exercise
+        respond_to do |format|
+          format.js
+        end
+      end
+    end
+  end
+
+  def edit
+    respond_to do |format|
+      format.html{render :layout => 'base_courses'}
+  end
+  end
+
+  def update
+    @exercise.exercise_name = params[:exercise][:exercise_name]
+    @exercise.exercise_description = params[:exercise][:exercise_description]
+    @exercise.time =  params[:exercise][:time].blank? ? -1 : params[:exercise][:time]
+    @exercise.end_time = Time.at(params[:exercise][:end_time].to_time.to_i + 16*60*60 -1)
+    @exercise.publish_time = params[:exercise][:publish_time]
+    @exercise.show_result = params[:exercise][:show_result].blank? ? 1 : params[:exercise][:show_result]
+    if @exercise.save
+      respond_to do |format|
+        format.js
+      end
+    else
+      render_404
+      end
+  end
+
+  def destroy
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
+    if @exercise && @exercise.destroy
+      if @is_teacher
+        exercises = Exercise.where("course_id =?", @course.id)
+      else
+        exercises = Exercise.where("course_id =? and exercise_status =?", @course.id, 2)
+      end
+      @exercises = paginateHelper exercises,20 #分页
+      respond_to do |format|
+        format.js
+      end
+    end
+  end
+
+  # 统计结果
+  def statistics_result
+    @exercise = Exercise.find(params[:id])
+    exercise_questions = @exercise.exercise_questions
+    @exercise_questions = paginateHelper exercise_questions, 5
+    respond_to do |format|
+      format.html{render :layout => 'base_courses'}
+    end
+  end
+
+  # 添加题目
+  # question_type 1：单选 2：多选 3：填空题
+  def create_exercise_question
+    question_title = params[:question_title].nil? || params[:question_title].empty? ? l(:label_enter_single_title) : params[:question_title]
+    option = {
+        :question_title => question_title,
+        :question_type => params[:question_type] || 1,
+        :question_number => params[:question_type] == "1"? @exercise.exercise_questions.where("question_type = 1").count + 1 :
+                              (params[:question_type] == "2" ? (@exercise.exercise_questions.where("question_type = 2").count + 1) :
+                              @exercise.exercise_questions.where("question_type = 3").count + 1),
+        :question_score => params[:question_score]
+    }
+    @exercise_questions = @exercise.exercise_questions.new option
+    # params[:question_answer] 题目选项
+    if params[:question_answer]
+      for i in 1..params[:question_answer].count
+        answer = (params[:question_answer].values[i-1].nil? || params[:question_answer].values[i-1].empty?) ? l(:label_new_answer) : params[:question_answer].values[i-1]
+        question_option = {
+            :choice_position => i,
+            :choice_text => answer
+        }
+        @exercise_questions.exercise_choices.new question_option
+      end
+    end
+    # 如果是插入的话，那么从插入的这个id以后的question_num都将要+1
+    if params[:quest_id]
+      @is_insert = true
+      if @exercise_questions.question_type == 1
+        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 1).update_all(" question_number = question_number + 1")
+        #@exercise.exercise_questions.where("question_number > #{params[:quest_num].to_i} and question_type == 1").update_all(" question_number = question_number + 1")
+      elsif @exercise_questions.question_type == 2
+        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 2).update_all(" question_number = question_number + 1")
+      else
+        ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 3).update_all(" question_number = question_number + 1")
+      end
+      # @exercise_question_num = params[:quest_num].to_i
+      @exercise_questions.question_number = params[:quest_num].to_i + 1
+    end
+    if @exercise_questions.save
+      # params[:exercise_choice] 标准答案参数
+      # 问答题标准答案有三个，单独处理
+      if @exercise_questions.question_type == 3
+        for i in 1..params[:exercise_choice].count
+          standart_answer = ExerciseStandardAnswer.new
+          standart_answer.exercise_question_id =  @exercise_questions.id
+          standart_answer.answer_text = params[:exercise_choice].values[i-1]
+          standart_answer.save
+        end
+      else
+        standart_answer = ExerciseStandardAnswer.new
+        standart_answer.exercise_question_id =  @exercise_questions.id
+        if  @exercise_questions.question_type == 1
+          standart_answer.exercise_choice_id = sigle_selection_standard_answer(params[:exercise_choice])
+        else
+          standart_answer.exercise_choice_id = multiselect_standard_answer(params[:exercise_choice])
+        end
+        standart_answer.save
+      end
+      respond_to do |format|
+        format.js
+      end
+    end
+
+  end
+
+  # 修改题目
+  # params[:exercise_question]  The id of exercise_question
+  # params[:question_answer]  eg:A、B、C选项
+  def update_exercise_question
+    @exercise_question = ExerciseQuestion.find params[:exercise_question]
+    @exercise_question.question_title = params[:question_title].nil? || params[:question_title].empty? ? l(:label_enter_single_title) : params[:question_title]
+    @exercise_question.question_score = params[:question_score]
+    # 处理选项:如果选了某个选项，那么则要删除之前的选项
+    if params[:question_answer]
+      @exercise_question.exercise_choices.each do |answer|
+        answer.destroy unless params[:question_answer].keys.include? answer.id.to_s
+      end
+      for i in 1..params[:question_answer].count
+        question = @exercise_question.exercise_choices.find_by_id params[:question_answer].keys[i-1]
+        answer = (params[:question_answer].values[i-1].nil? || params[:question_answer].values[i-1].empty?) ? l(:label_new_answer) : params[:question_answer].values[i-1]
+        if question
+          question.choice_position = i
+          question.choice_text = answer
+          question.save
+        else
+          question_option = {
+              :choice_position => i,
+              :choice_text => answer
+          }
+          @exercise_question.exercise_choices.new question_option
+        end
+      end
+    end
+    # 更新标准答案
+    if params[:exercise_choice]
+      if @exercise_question.question_type == 3
+        # 删除不合理的选项
+        @exercise_question.exercise_standard_answers.each do |answer|
+          answer.destroy unless params[:exercise_choice].keys.include? answer.id.to_s
+        end
+        for i in 1..params[:exercise_choice].count
+          # 找到对应的标准答案
+          question_standart = @exercise_question.exercise_standard_answers.find_by_id params[:exercise_choice].keys[i-1]
+          # 标准答案值
+          answer_standart = (params[:exercise_choice].values[i-1].nil? || params[:exercise_choice].values[i-1].empty?) ? l(:label_new_answer) : params[:exercise_choice].values[i-1]
+          if question_standart
+            question_standart.answer_text = answer_standart
+            question_standart.save
+          else
+            standart_answer_option = {
+                :answer_text => answer_standart
+            }
+            @exercise_question.exercise_standard_answers.new standart_answer_option
+          end
+        end
+      else
+        answer_standart = @exercise_question.exercise_standard_answers.first
+        answer_standart.exercise_choice_id = @exercise_question.question_type == 1 ? sigle_selection_standard_answer(params[:exercise_choice]) : multiselect_standard_answer(params[:exercise_choice])
+        answer_standart.save
+      end
+      @exercise_question.save
+      respond_to do |format|
+        format.js
+      end
+    end
+  end
+
+  # 删除题目
+  def delete_exercise_question
+    @exercise_question = ExerciseQuestion.find params[:exercise_question]
+    @exercise = @exercise_question.exercise
+
+    if @exercise_question.question_type == 1
+      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 1).update_all(" question_number = question_number - 1")
+      #@exercise.exercise_questions.where("question_number > #{params[:quest_num].to_i} and question_type == 1").update_all(" question_number = question_number + 1")
+    elsif @exercise_question.question_type == 2
+      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 2).update_all(" question_number = question_number - 1")
+    else
+      ExerciseQuestion.where("question_number>? and question_type=?",params[:quest_num].to_i, 3).update_all(" question_number = question_number - 1")
+    end
+    # @exercise_question_num = params[:quest_num].to_i
+    # @exercise_questions.question_number = params[:quest_num].to_i - 1
+    #
+    # exercise_questions = @exercise.exercise_questions.where("question_number > #{@exercise_question.question_number}")
+    # exercise_questions.each do |question|
+    #   question.question_number -= 1
+    #   question.save
+    # end
+    if @exercise_question && @exercise_question.destroy
+      respond_to do |format|
+        format.js
+      end
+    end
+  end
+
+  # 发布试卷
+  def publish_exercise
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
+    @index = params[:index]
+    @exercise.exercise_status = 2
+    @exercise.publish_time = Time.now
+    if @exercise.save
+      @exercise.course.members.each do |m|
+         @exercise.course_messages << CourseMessage.create(:user_id =>m.user_id, :course_id => @exercise.course.id, :viewed => false,:status=>2)
+      end
+      #redirect_to exercise_index_url(:course_id=> @course.id)
+      respond_to do |format|
+        format.js
+      end
+    end
+  end
+
+  # 重新发布试卷
+  # 重新发布的时候会删除所有的答题
+  def republish_exercise
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course)
+    @index = params[:index]
+    @exercise.exercise_questions.each do |exercise_question|
+      exercise_question.exercise_answers.destroy_all
+    end
+    @exercise.course_messages.destroy_all
+    @exercise.exercise_users.destroy_all
+    @exercise.exercise_status = 1
+    @exercise.publish_time = nil
+    @exercise.save
+    respond_to do |format|
+      format.js
+    end
+  end
+
+  def student_exercise_list
+=begin
+    if @exercise.end_time <= Time.now
+      @course.student.each do |student|
+        if ExerciseUser.where("user_id = ? && exercise_id = ?",student.student_id,@exercise.id).empty?
+          ExerciseUser.create(:user_id => student.student_id, :exercise_id => @exercise.id, :start_at => @exercise.end_time, :status => true,:score=>0)
+        end
+
+        s_score = calculate_student_score(@exercise, student.student)
+        exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", student.student_id, @exercise.id).first
+        exercise_user.update_attributes(:score => s_score)
+      end
+    end
+=end
+    @is_teacher = User.current.allowed_to?(:as_teacher,@course) || User.current.admin?
+    @all_exercises = @course.exercises.where("exercise_status > 1").order("created_at desc")
+    @exercise_count = @exercise.exercise_users.where('score is not NULL').count
+    if @is_teacher || (!@exercise.exercise_users.where(:user_id => User.current.id).empty? && @exercise.end_time <= Time.now)
+      @exercise_users_list = @exercise.exercise_users.where('score is not NULL')
+      @show_all = true;
+    elsif !@exercise.exercise_users.where(:user_id => User.current.id).empty? && @exercise.end_time > Time.now
+      @exercise_users_list = @exercise.exercise_users.where("user_id = ? and score is not NULL",User.current.id)
+    else
+      @exercise_users_list = []
+    end
+    respond_to do |format|
+      format.html
+    end
+  end
+
+  # 学生提交答卷，选中答案的过程中提交
+  def commit_answer
+    eq = ExerciseQuestion.find(params[:exercise_question_id])
+    # 已提交过的且是限时的则不允许答题
+    if (has_commit_exercise?(@exercise.id,User.current.id) && (!User.current.admin?) && @exercise.time != -1) || @exercise.end_time < Time.now
+      render :json => {:text => "failure"}
+      return
+    end
+    if eq.question_type == 1
+      # 单选题
+      ea = ExerciseAnswer.find_by_exercise_question_id_and_user_id(params[:exercise_question_id],User.current.id)
+      if ea.nil?
+        # 尚未答该题，添加答案
+        ea = ExerciseAnswer.new
+        ea.user_id = User.current.id
+        ea.exercise_question_id = params[:exercise_question_id]
+      end
+      #修改该题对应答案
+      ea.exercise_choice_id = params[:exercise_choice_id]
+      if ea.save
+        # 保存成功返回成功信息及当前以答题百分比
+        uncomplete_question = get_uncomplete_question(@exercise, User.current)
+        if uncomplete_question.count < 1
+          complete = 1;
+        else
+          complete = 0;
+        end
+        @percent = get_percent(@exercise,User.current)
+        render :json => {:text => "ok" ,:complete => complete,:percent => format("%.2f" ,@percent)}
+      else
+        #返回失败信息
+        render :json => {:text => "failure"}
+      end
+    elsif eq.question_type == 2
+      #多选题
+      ea = ExerciseAnswer.find_by_exercise_choice_id_and_user_id(params[:exercise_choice_id],User.current.id)
+      if ea.nil?
+        #尚未答该题，添加答案
+        ea = ExerciseAnswer.new
+        ea.user_id = User.current.id
+        ea.exercise_question_id = params[:exercise_question_id]
+        ea.exercise_choice_id = params[:exercise_choice_id]
+        if ea.save
+          uncomplete_question = get_uncomplete_question(@exercise, User.current)
+          if uncomplete_question.count < 1
+            complete = 1;
+          else
+            complete = 0;
+          end
+          @percent = get_percent(@exercise,User.current)
+          render :json => {:text => "ok",:complete => complete,:percent => format("%.2f" ,@percent)}
+        else
+          render :json => {:text => "failure"}
+        end
+      else
+        #pv不为空，则当前选项之前已被选择，再次点击则是不再选择该项，故删除该答案
+        if ea.delete
+          @percent = get_percent(@exercise, User.current)
+          render :json => {:text => "false" ,:percent => format("%.2f" , @percent)}
+        else
+          render :json => {:text => "failure"}
+        end
+      end
+    elsif eq.question_type == 3
+      #单行文本，多行文本题
+      ea = ExerciseAnswer.find_by_exercise_question_id_and_user_id(params[:exercise_question_id], User.current.id)
+      if ea.nil?
+        # ea为空之前尚未答题，添加答案
+        if params[:answer_text].nil? || params[:answer_text].blank?
+          #用户提交空答案，视作不作答
+          @percent = get_percent(@exercise,User.current)
+          render :json => {:text => "",:percent => format("%.2f", @percent)}
+        else
+          #添加答案
+          ea = ExerciseAnswer.new
+          ea.user_id = User.current.id
+          ea.exercise_question_id = params[:exercise_question_id]
+          ea.answer_text = params[:answer_text]
+          if ea.save
+            uncomplete_question = get_uncomplete_question(@exercise, User.current)
+            if uncomplete_question.count < 1
+              complete = 1;
+            else
+              complete = 0;
+            end
+            @percent = get_percent(@exercise,User.current)
+            render :json => {:text => ea.answer_text,:complete => complete,:percent => format("%.2f",@percent)}
+          else
+            render :json => {:text => "failure"}
+          end
+        end
+      else
+        # ea不为空说明用户之前已作答
+        if params[:answer_text].nil? || params[:answer_text].blank?
+          # 用户提交空答案，视为删除答案
+          if ea.delete
+            @percent = get_percent(@exercise,User.current)
+            render :json => {:text => "",:percent => format("%.2f", @percent)}
+          else
+            render :json => {:text => "failure"}
+          end
+        else
+          #用户修改答案
+          ea.answer_text = params[:answer_text]
+          if ea.save
+            @percent = get_percent(@exercise,User.current)
+            render :json => {:text => ea.answer_text,:percent => format("%.2f", @percent)}
+          else
+            render :json => {:text => "failure"}
+          end
+        end
+      end
+
+    else
+      render :json => {:text => "failure"}
+    end
+  end
+
+  # 提交问卷
+  def commit_exercise
+    # 老师不需要提交
+    if User.current.allowed_to?(:as_teacher,@course)
+      if @exercise.publish_time.nil?
+        @exercise.update_attributes(:show_result => params[:show_result])
+        @exercise.update_attributes(:exercise_status => 2)
+        @exercise.update_attributes(:publish_time => Time.now)
+        course = @exercise.course
+        course.members.each do |m|
+          @exercise.course_messages << CourseMessage.new(:user_id => m.user_id, :course_id => course.id, :viewed => false, :status => 2)
+        end
+        redirect_to exercise_url(@exercise)
+        return
+      elsif @exercise.publish_time > Time.now
+        @exercise.update_attributes(:show_result => params[:show_result])
+        redirect_to exercise_url(@exercise)
+        return
+      end
+      @exercise.update_attributes(:show_result => params[:show_result])
+      redirect_to exercise_url(@exercise)
+      # REDO: 提示提交成功
+    else
+      # 更新提交状态
+      cur_exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", User.current, @exercise.id).first
+      cur_exercise_user.update_attributes(:status => 1)
+      # 答题过程中需要统计完成量
+      @uncomplete_question = get_uncomplete_question(@exercise, User.current)
+      # 获取改学生的考试得分
+      @score = calculate_student_score(@exercise, User.current)
+      # @score = 100
+      if @uncomplete_question.count < 1
+        # 查看是否有已提交记录
+        cur_exercise_user.score = @score
+        if cur_exercise_user.save
+        #redirect_to poll_index_path(:polls_group_id => @course.id,:polls_type => 'Course')
+          @status = 0 #提交成功
+        else
+          @status = 2 #未知错误
+        end
+      else
+        @status = 1 #有未做得必答题
+      end
+      @save = params[:save].to_i if params[:save]
+      respond_to do |format|
+        format.js
+      end
+    end
+  end
+
+  #查看学生的答卷情况
+  def show_student_result
+    @user = User.find params[:user_id]
+    @can_edit_excercise = false
+    @exercise_questions = @exercise.exercise_questions
+    score = calculate_student_score(@exercise, @user)
+    eu = get_exercise_user(@exercise.id, @user.id)
+    eu.update_attributes(:score => score)
+    @exercise_user = ExerciseUser.where("user_id =? and exercise_id=?", @user.id, @exercise.id).first
+    respond_to do |format|
+      format.html {render :layout => 'base_courses'}
+    end
+  end
+
+  # 计算学生得分
+  def calculate_student_score(exercise, user)
+    score = 0
+    score1 = 0
+    score2 = 0
+    score3 = 0
+    exercise_qustions = exercise.exercise_questions
+    exercise_qustions.each do |question|
+      answer = get_user_answer(question, user)
+      standard_answer = get_user_standard_answer(question, user)
+      unless answer.empty?
+        # 问答题有多个答案
+        if question.question_type == 3 && !standard_answer.empty?
+          if standard_answer.include?(answer.first.answer_text)
+            score1 = score1+ question.question_score unless question.question_score.nil?
+          end
+        elsif question.question_type == 1 && !standard_answer.nil?
+          if answer.first.exercise_choice.choice_position == standard_answer.exercise_choice_id
+            score2 = score2 + question.question_score unless question.question_score.nil?
+          end
+        elsif question.question_type == 2 && !standard_answer.nil?
+          arr = get_mulscore(question, user)
+          if arr.to_i == standard_answer.exercise_choice_id
+            score3 = score3 + question.question_score unless question.question_score.nil?
+          end
+          # ecs = ExerciseAnswer.where("user_id =? and exercise_question_id =?", user.id, question.id)
+          # arr = []
+          # ecs.each do |ec|
+          #   arr << ec.exercise_choice.choice_position
+          # end
+          # arr.sort
+          # arr = arr.join("")
+          # if arr.to_i == standard_answer.exercise_choice_id
+          #   score3 = score + question.question_score unless question.question_score.nil?
+          # end
+        end
+      end
+    end
+    score = score1 + score2 + score3
+  end
+
+  private
+
+  # ExerciseUser记录用户是否已提交问卷有对应的记录则已提交，没有则新建一个
+  def get_exercise_user exercise_id,user_id
+    eu = ExerciseUser.find_by_exercise_id_and_user_id(exercise_id,user_id)
+    if eu.nil?
+      eu = ExerciseUser.new
+    end
+    eu
+  end
+
+  # 获取当前学生回答问题的答案
+  def get_user_answer(question,user)
+    # user_answer = ExerciseAnswer.where("user_id=? and exercise_question_id=?", user.id, question.id).first
+    user_answer = question.exercise_answers.where("#{ExerciseAnswer.table_name}.user_id = #{user.id}")
+    user_answer
+  end
+
+  # 获取问题的标准答案
+  def get_user_standard_answer(question,user)
+    if question.question_type == 3
+      standard_answer =[]
+      question.exercise_standard_answers.each do |answer|
+        standard_answer << answer.answer_text
+      end
+    else
+      standard_answer = question.exercise_standard_answers.first
+    end
+    standard_answer
+  end
+  # 是否完成了答题
+  def get_complete_question(exercise,user)
+    questions = exercise.exercise_questions
+    complete_question = []
+    questions.each do |question|
+      answers = get_user_answer(question,user)
+      if !(answers.nil? || answers.count < 1)
+        complete_question << question
+      end
+    end
+    complete_question
+  end
+
+  # 获取答题百分比
+  def get_percent exercise,user
+    complete_count = get_complete_question(exercise,user).count
+    if exercise.exercise_questions.count == 0
+      return 0
+    else
+      return (complete_count.to_f / exercise.exercise_questions.count.to_f)*100
+    end
+  end
+
+  def remove_invalid_exercise(course)
+    exercises = course.exercises.where("exercise_name=?","")
+    unless exercises.empty?
+      exercises.each do |exercise|
+        if exercise.exercise_questions.empty?
+          exercise.destroy
+        end
+      end
+    end
+  end
+
+  def find_exercise_and_course
+    @exercise = Exercise.find params[:id]
+    @course = Course.find @exercise.course_id
+  rescue Exception => e
+    render_404
+  end
+
+  def find_course
+    @course = Course.find params[:course_id]
+  rescue Exception => e
+    render_404
+  end
 end
\ No newline at end of file