package com.guo.learningprogresstracker.service.impl;

import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.guo.learningprogresstracker.entity.StudyExpectationsEntity;
import com.guo.learningprogresstracker.entity.StudySessionsEntity;
import com.guo.learningprogresstracker.exception.ErrorParameterException;
import com.guo.learningprogresstracker.mapper.StudyExpectationsMapper;
import com.guo.learningprogresstracker.mapper.StudySessionsMapper;
import com.guo.learningprogresstracker.service.StudyExpectationsService;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;

/**
 * 学习预期服务实现
 */
@Service
@RequiredArgsConstructor
public class StudyExpectationsServiceImpl implements StudyExpectationsService {

    private final StudyExpectationsMapper studyExpectationsMapper;
    private final StudySessionsMapper studySessionsMapper;

    @Override
    public StudyExpectationsEntity upsertExpectation(String sessionNum, String description) throws ErrorParameterException {
        boolean sessionExists = studySessionsMapper.exists(
                Wrappers.<StudySessionsEntity>lambdaQuery()
                        .eq(StudySessionsEntity::getSessionNum, sessionNum));
        if (!sessionExists) {
            throw new ErrorParameterException("学习会话[" + sessionNum + "]不存在");
        }

        StudyExpectationsEntity existing = getBySessionNum(sessionNum);
        if (existing == null) {
            StudyExpectationsEntity entity = new StudyExpectationsEntity();
            entity.setSessionNum(sessionNum);
            entity.setDescription(description);
            studyExpectationsMapper.insert(entity);
            return entity;
        }
        existing.setDescription(description);
        studyExpectationsMapper.updateById(existing);
        return existing;
    }

    @Override
    public StudyExpectationsEntity getBySessionNum(String sessionNum) {
        return studyExpectationsMapper.selectOne(
                Wrappers.<StudyExpectationsEntity>lambdaQuery()
                        .eq(StudyExpectationsEntity::getSessionNum, sessionNum)
                        .last("LIMIT 1"));
    }
}