package com.nju.edu.eval.service.serviceImpl;

import com.nju.edu.eval.data.dao.CourseDao;
import com.nju.edu.eval.data.dao.UserDao;
import com.nju.edu.eval.data.entity.Course;
import com.nju.edu.eval.data.entity.User;
import com.nju.edu.eval.exception.MyServiceException;
import com.nju.edu.eval.model.vo.course.CourseVO;
import com.nju.edu.eval.service.CourseService;
import com.nju.edu.eval.service.convertor.CourseConvertor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.stream.Collectors;

/**
 * @author weijin
 */
@Service
public class CourseServiceImpl implements CourseService {
    private final CourseDao courseDao;

    private final UserDao userDao;

    @Autowired
    public CourseServiceImpl(CourseDao courseDao, UserDao userDao) {
        this.courseDao = courseDao;
        this.userDao = userDao;
    }

    @Override
    public CourseVO createCourse(CourseVO courseVO, Integer teacherId) {
        Course course = new Course(courseVO.getName(), courseVO.getCode(), teacherId, courseVO.getIsPublic()?1:0);
        courseDao.save(course);
        courseVO.setId(course.getId());
        return courseVO;
    }

    @Override
    public boolean updateCourse(CourseVO courseVO, Integer teacherId) {
        Course course = courseDao.findById(courseVO.getId()).orElse(null);
        if (course == null) {
            throw new MyServiceException("A0201", "无对应的课程");
        }
        else if (!teacherId.equals(course.getTeacherId())) {
            throw new MyServiceException("A0301", "访问未授权");
        } else {
            Course course1 = CourseConvertor.convertToEntity(courseVO);
            course1.setTeacherId(course.getTeacherId());
            courseDao.save(course1);
            return true;
        }
    }

    @Override
    public List<CourseVO> getCourseByTeacher(Integer teacherId) {
        User user = userDao.findById(teacherId).orElse(null);
        if (user == null) {
            throw new MyServiceException("A0201", "用户账号不存在");
        } else {
            return courseDao.findAllByTeacherId(teacherId).stream()
                    .map(CourseConvertor::convertToVO).collect(Collectors.toList());
        }
    }

}