educoder/app/controllers/course_videos_controller.rb

class CourseVideosController < ApplicationController
  before_action :require_login
  before_action :validate_params, except: [:watch_histories]
  before_action :find_course, only: [:create]
  before_action :find_video, only: [:update, :watch_histories]
  before_action :teacher_allowed, except: [:watch_histories]

  def create
    title = params[:name].strip
    link = params[:link].strip
    course_second_category_id = params[:category_id] || 0
    @course.course_videos.create!(title: title, link: link, is_link: 1, user_id: current_user.id, course_second_category_id: course_second_category_id)
    render_ok
  end

  def update
    title = params[:name].strip
    link = params[:link].strip
    @video.update!(title: title, link: link)
    render_ok
  end

  def watch_histories
    return normal_status(403, "你没有权限操作") if !current_user.teacher_of_course?(@course)
    course_video = CourseVideo.find(@video.id)

    @watch_course_videos = course_video.watch_course_videos.includes(:user, :watch_video_histories).where("end_at IS NOT NULL")
    @count = @watch_course_videos.count

    if params[:group_id].present?
      @watch_course_videos = @watch_course_videos.joins("
        JOIN course_members ON course_members.user_id = watch_course_videos.user_id AND course_members.course_id = #{@course.id}
      ").where("course_members.course_group_id = ?", params[:group_id])
    end
    @watch_course_videos = paginate @watch_course_videos
  end

  private

  def validate_params
    tip_exception("视频名称不能为空") if params[:name].blank?
    tip_exception("链接地址不能为空") if params[:link].blank?
  end

  def find_video
    @video = CourseVideo.find params[:id]
    @course = @video.course
  end

end