package com.njuzr.eaibackend.service.impl;

import com.baomidou.mybatisplus.core.toolkit.StringUtils;
import com.njuzr.eaibackend.dto.CourseDTO;
import com.njuzr.eaibackend.exception.MyException;
import com.njuzr.eaibackend.mapper.CourseMapper;
import com.njuzr.eaibackend.po.Course;
import com.njuzr.eaibackend.service.CourseService;
import com.njuzr.eaibackend.utils.ConvertUtil;
import com.njuzr.eaibackend.utils.ModelMapperUtil;
import com.njuzr.eaibackend.vo.CourseVO;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Service;

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

/**
 * @author: Leonezhurui
 * @Date: 2024/3/5 - 22:09
 * @Package: EAI-Backend
 */

@Slf4j
@Service
public class CourseServiceImpl implements CourseService {

    private final CourseMapper courseMapper;

    @Autowired
    public CourseServiceImpl(CourseMapper courseMapper) {
        this.courseMapper = courseMapper;
    }


    @Override
    public CourseVO createCourse(CourseDTO courseDTO) {
        log.info("解析CourseDTO："+courseDTO.toString());
        // 类型转换
        Course targetCourse = convertToPO(courseDTO);
        targetCourse.setCreateTime(new Date());

        log.info("类型转换后的targetCourse"+targetCourse);

        // 插入数据库
        int status = courseMapper.insert(targetCourse);
        if (status == 0) {
            log.error("创建课程失败，数据库插入错误！");
            throw new MyException(HttpStatus.INTERNAL_SERVER_ERROR.value(), HttpStatus.INTERNAL_SERVER_ERROR.getReasonPhrase()+"："+"创建课程错误");
        }

        return convertToVO(targetCourse);
    }


    @Override
    public CourseVO findByCourseId(Long courseId) {
        Course res = courseMapper.selectById(courseId);
        return convertToVO(res);
    }

    /**
     * 将DTO转换成PO
     * @param courseDTO
     * @return
     */
    private Course convertToPO(CourseDTO courseDTO) {
        Course course = new Course();
        BeanUtils.copyProperties(courseDTO, course);
        course.setTeacherIds(ConvertUtil.listToString(courseDTO.getTeacherIds()));
        if (courseDTO.getCourseImages() != null)
            course.setCourseImages(ConvertUtil.listToString(courseDTO.getCourseImages()));
        return course;
    }

    /**
     * 将PO转换成VO
     * @param course
     * @return
     */
    private CourseVO convertToVO(Course course) {
        CourseVO res = new CourseVO();
        BeanUtils.copyProperties(course, res);
        res.setTeacherIds(ConvertUtil.stringToList(course.getTeacherIds(), Long::valueOf));
        if (course.getCourseImages() != null)
            res.setCourseImages(ConvertUtil.stringToList(course.getCourseImages(), String::valueOf));

        return res;
    }


}