educoder/app/services/exercise_user_pdf_service.rb

class ExerciseUserPdfService
  include ExercisesHelper
  include ApplicationHelper
  include StudentWorksHelper

  attr_reader :exercise, :ex_user

  def initialize(exercise, ex_user)
    @exercise = exercise
    @ex_user = ex_user
    @ex_user_user = @ex_user.user
    @course = @exercise.course
  end

  def filename
    user_course = @course.course_members.find_by(user_id:@ex_user_user.id).course_group_name
    exercise_user_name = user_course + "_" + exercise.exercise_name + "_" + @ex_user_user.real_name
    "#{exercise_user_name.strip}.pdf"
  end

  def prepare_binding
    load_data

    binding
  end

  def ex_pdf
    generate_pdf
  end

  private

  def generate_pdf
    file = File.open(Rails.root.join('app/templates/exercise_export/exercise_user.html.erb'))
    html = ERB.new(file.read).result(prepare_binding)

    kit = PDFKit.new(html)
    base_css = %w(app/templates/exercise_export/exercise_export.css)
    base_css.each { |css| kit.stylesheets << Rails.root.join(css) }
    #-----正式需删掉
    # aa = File.open(Rails.root.join("public/123.html"),"w+")
    # aa.syswrite(kit.source)
    #正式需删掉-------
    file = Tempfile.new(filename)
    kit.to_pdf(file.path)
    file
  end

  def load_data
    @exercise_questions = exercise.exercise_questions
    @exercise_ques_count = @exercise_questions.count # 全部的题目数
    @exercise_ques_scores = @exercise_questions.pluck(:question_score).sum

    #单选题的数量及分数
    exercise_single_ques = @exercise_questions.find_by_custom("question_type",0)
    @exercise_single_ques_count = exercise_single_ques.all.count
    @exercise_single_ques_scores = exercise_single_ques.pluck(:question_score).sum

    #多选题的数量及分数
    exercise_double_ques = @exercise_questions.find_by_custom("question_type",1)
    @exercise_double_ques_count = exercise_double_ques.all.count
    @exercise_double_ques_scores = exercise_double_ques.pluck(:question_score).sum

    # 判断题数量及分数
    exercise_ques_judge = @exercise_questions.find_by_custom("question_type",2)
    @exercise_ques_judge_count = exercise_ques_judge.all.count
    @exercise_ques_judge_scores = exercise_ques_judge.pluck(:question_score).sum

    #填空题数量及分数
    exercise_ques_null = @exercise_questions.find_by_custom("question_type",3)
    @exercise_ques_null_count = exercise_ques_null.all.count
    @exercise_ques_null_scores = exercise_ques_null.pluck(:question_score).sum

    #简答题数量及分数
    exercise_ques_main = @exercise_questions.find_by_custom("question_type",4)
    @exercise_ques_main_count = exercise_ques_main.all.count
    @exercise_ques_main_scores = exercise_ques_main.pluck(:question_score).sum

    #实训题数量及分数
    exercise_ques_shixun = @exercise_questions.find_by_custom("question_type",5)
    @exercise_ques_shixun_count = exercise_ques_shixun.all.count
    @exercise_ques_shixun_scores = exercise_ques_shixun.pluck(:question_score).sum

    @exercise_questions = @exercise_questions.includes(:exercise_choices,:exercise_shixun_challenges,:exercise_answers,:exercise_shixun_answers,:exercise_answer_comments,:exercise_standard_answers)
    get_each_student_exercise(exercise.id,@exercise_questions,@ex_user_user.id)

  end
end